Import of a BSD-licensed version of `patch', which will eventually

replace the version we currently have in src/gnu/usr.bin/patch/.
Among other things, this version includes a --posix option for strict
POSIX conformance.

This version is the current source from OpenBSD as of today.  It is
their 3.5-release, plus a few updates to patch.c and pch.c that they
made about three weeks ago.

14 files changed, 4176 insertions, 2807 deletions

diff --git a/usr.bin/patch/Makefile b/usr.bin/patch/Makefile
index d6db9f7..9c54a92 100644
--- a/usr.bin/patch/Makefile
+++ b/usr.bin/patch/Makefile
@@ -1,6 +1,6 @@
-#	@(#)Makefile	8.1 (Berkeley) 6/6/93
+#	$OpenBSD: Makefile,v 1.3 2003/07/18 02:00:09 deraadt Exp $
 
 PROG=	patch
-SRCS=	patch.c pch.c inp.c version.c util.c
+SRCS=	patch.c pch.c inp.c util.c backupfile.c
 
 .include <bsd.prog.mk>
diff --git a/usr.bin/patch/README b/usr.bin/patch/README
index 017b1a0..72c1064 100644
--- a/usr.bin/patch/README
+++ b/usr.bin/patch/README
@@ -1,16 +1,72 @@
-
-The Makefile and config.h files in this directory work with the current
-BSD release.  Don't run the Configure script, you'll get wrong results.
-
-Keith Bostic 1/10/88
------------------------------------------------------------------------------
+this version modified to fit in with the 386bsd release.
+this isn't gnu software, so we're not obligated to give
+you the original sources -- if you want them, get them
+from prep.ai.mit.edu:pub/gnu/patch-2.0.12u8.tar.z
+
+					-- cgd
+
+#######################################################################
+
+
+This version of patch contains modifications made by the Free Software
+Foundation, summarized in the file ChangeLog.  Primarily they are to
+support the unified context diff format that GNU diff can produce, and
+to support making GNU Emacs-style backup files.  They also include
+fixes for some bugs.
+
+There are two GNU variants of patch: this one, which retains Larry
+Wall's interactive Configure script and has patchlevels starting with
+`12u'; and another one that has a GNU-style non-interactive configure
+script and accepts long-named options, and has patchlevels starting
+with `12g'.  Unlike the 12g variant, the 12u variant contains no
+copylefted code, for the paranoid.  The two variants are otherwise the
+same.  They should be available from the same places.
+
+The FSF is distributing this version of patch independently because as
+of this writing, Larry Wall has not released a new version of patch
+since mid-1988.  I have heard that he has been too busy working on
+other things, like Perl.
+
+Here is a wish list of some projects to improve patch:
+
+1.  Correctly handle files and patchfiles that contain NUL characters.
+This is hard to do straightforwardly; it would be less work to
+adopt a kind of escape encoding internally.
+Let ESC be a "control prefix".  ESC @ stands for NUL.  ESC [ stands for ESC.
+You need to crunch this when reading input (replace fgets),
+and when writing the output file (replace fputs),
+but otherwise everything can go along as it does now.
+Be careful to handle reject files correctly;
+I think they are currently created using `write', not `fputs'.
+
+2.  Correctly handle patches produced by GNU diff for files that do
+not end with a newline.
+
+Please send bug reports for this version of patch to
+bug-gnu-utils@prep.ai.mit.edu as well as to Larry Wall (lwall@netlabs.com).
+ --djm@gnu.ai.mit.edu (David MacKenzie)
 
 			Patch Kit, Version 2.0
 
-		    Copyright (c) 1986, Larry Wall
-
-You may copy the patch kit in whole or in part as long as you don't try to
-make money off it, or pretend that you wrote it.
+		    Copyright (c) 1988, Larry Wall
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following condition
+is met:
+ 1. Redistributions of source code must retain the above copyright
+    notice, this condition and the following disclaimer.
+
+THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGE.
 --------------------------------------------------------------------------
 
 Please read all the directions below before you proceed any further, and
@@ -34,7 +90,8 @@ Installation
     of Configure and generate the defines by hand.
 
 2)  Glance through config.h to make sure system dependencies are correct.
-    Most of them should have been taken care of by running the Configure script.
+    Most of them should have been taken care of by running the
+    Configure script. 
 
     If you have any additional changes to make to the C definitions, they
     can be done in the Makefile, or in config.h.  Bear in mind that they may
@@ -53,27 +110,14 @@ Installation
 5)  Read the manual entry before running patch.
 
 6)  IMPORTANT!  Help save the world!  Communicate any problems and
-    suggested patches to me, lwall@sdcrdcf.UUCP (Larry Wall), so we can
-    keep the world in sync.  If you have a problem, there's someone else
-    out there who either has had or will have the same problem.
+    suggested patches to me, lwall@netlabs.com (Larry Wall),
+    so we can keep the world in sync.  If you have a problem, there's
+    someone else out there who either has had or will have the same problem.
 
     If possible, send in patches such that the patch program will apply them.
     Context diffs are the best, then normal diffs.  Don't send ed scripts--
     I've probably changed my copy since the version you have.
 
-    Watch for patch patches in net.sources.bugs.  Patches will generally be
-    in a form usable by the patch program.  If you are just now bringing up
-    patch and aren't sure how many patches there are, write to me and I'll
-    send any you don't have.  Your current patch level is shown in patchlevel.h.
-
-
-NEW FEATURES IN THIS RELEASE
-
-(Correct) support for 4.3bsd-style context diffs.
-Files can be created from scratch.
-You can specify a fuzz-factor for context matching.
-You can force patch to ask no questions.
-You can specify how much of the leading pathname to strip off filenames.
-Uses a Configure script for greater portability.
-You are now asked if you want to apply a reversed patch.
-No limit (apart from memory) on the size of hunks.
+    Watch for patch patches in comp.sources.bugs.  Patches will generally be
+    in a form usable by the patch program.  Your current patch level
+    is shown in patchlevel.h.
diff --git a/usr.bin/patch/backupfile.c b/usr.bin/patch/backupfile.c
new file mode 100644
index 0000000..5863e9b
--- /dev/null
+++ b/usr.bin/patch/backupfile.c
@@ -0,0 +1,238 @@
+/*	$OpenBSD: backupfile.c,v 1.17 2003/08/01 20:30:48 otto Exp $	*/
+
+/*
+ * backupfile.c -- make Emacs style backup file names Copyright (C) 1990 Free
+ * Software Foundation, Inc.
+ * 
+ * This program is free software; you can redistribute it and/or modify it
+ * without restriction.
+ * 
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.
+ */
+
+/*
+ * David MacKenzie <djm@ai.mit.edu>. Some algorithms adapted from GNU Emacs.
+ */
+
+#ifndef lint
+static const char rcsid[] = "$OpenBSD: backupfile.c,v 1.17 2003/08/01 20:30:48 otto Exp $";
+#endif /* not lint */
+
+#include <ctype.h>
+#include <dirent.h>
+#include <libgen.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "backupfile.h"
+
+
+#define ISDIGIT(c) (isascii (c) && isdigit (c))
+
+/* Which type of backup file names are generated. */
+enum backup_type backup_type = none;
+
+/*
+ * The extension added to file names to produce a simple (as opposed to
+ * numbered) backup file name.
+ */
+char           *simple_backup_suffix = "~";
+
+static char    *concat(const char *, const char *);
+static char    *make_version_name(const char *, int);
+static int      max_backup_version(const char *, const char *);
+static int      version_number(const char *, const char *, int);
+static int      argmatch(const char *, const char **);
+static void     invalid_arg(const char *, const char *, int);
+
+/*
+ * Return the name of the new backup file for file FILE, allocated with
+ * malloc.  Return 0 if out of memory. FILE must not end with a '/' unless it
+ * is the root directory. Do not call this function if backup_type == none.
+ */
+char *
+find_backup_file_name(const char *file)
+{
+	char	*dir, *base_versions;
+	int	highest_backup;
+
+	if (backup_type == simple)
+		return concat(file, simple_backup_suffix);
+	base_versions = concat(basename(file), ".~");
+	if (base_versions == NULL)
+		return NULL;
+	dir = dirname(file);
+	if (dir == NULL) {
+		free(base_versions);
+		return NULL;
+	}
+	highest_backup = max_backup_version(base_versions, dir);
+	free(base_versions);
+	if (backup_type == numbered_existing && highest_backup == 0)
+		return concat(file, simple_backup_suffix);
+	return make_version_name(file, highest_backup + 1);
+}
+
+/*
+ * Return the number of the highest-numbered backup file for file FILE in
+ * directory DIR.  If there are no numbered backups of FILE in DIR, or an
+ * error occurs reading DIR, return 0. FILE should already have ".~" appended
+ * to it.
+ */
+static int
+max_backup_version(const char *file, const char *dir)
+{
+	DIR	*dirp;
+	struct dirent	*dp;
+	int	highest_version, this_version, file_name_length;
+
+	dirp = opendir(dir);
+	if (dirp == NULL)
+		return 0;
+
+	highest_version = 0;
+	file_name_length = strlen(file);
+
+	while ((dp = readdir(dirp)) != NULL) {
+		if (dp->d_namlen <= file_name_length)
+			continue;
+
+		this_version = version_number(file, dp->d_name, file_name_length);
+		if (this_version > highest_version)
+			highest_version = this_version;
+	}
+	closedir(dirp);
+	return highest_version;
+}
+
+/*
+ * Return a string, allocated with malloc, containing "FILE.~VERSION~".
+ * Return 0 if out of memory.
+ */
+static char *
+make_version_name(const char *file, int version)
+{
+	char	*backup_name;
+
+	if (asprintf(&backup_name, "%s.~%d~", file, version) == -1)
+		return NULL;
+	return backup_name;
+}
+
+/*
+ * If BACKUP is a numbered backup of BASE, return its version number;
+ * otherwise return 0.  BASE_LENGTH is the length of BASE. BASE should
+ * already have ".~" appended to it.
+ */
+static int
+version_number(const char *base, const char *backup, int base_length)
+{
+	int		version;
+	const char	*p;
+
+	version = 0;
+	if (!strncmp(base, backup, base_length) && ISDIGIT(backup[base_length])) {
+		for (p = &backup[base_length]; ISDIGIT(*p); ++p)
+			version = version * 10 + *p - '0';
+		if (p[0] != '~' || p[1])
+			version = 0;
+	}
+	return version;
+}
+
+/*
+ * Return the newly-allocated concatenation of STR1 and STR2. If out of
+ * memory, return 0.
+ */
+static char  *
+concat(const char *str1, const char *str2)
+{
+	char	*newstr;
+
+	if (asprintf(&newstr, "%s%s", str1, str2) == -1)
+		return NULL;
+	return newstr;
+}
+
+/*
+ * If ARG is an unambiguous match for an element of the null-terminated array
+ * OPTLIST, return the index in OPTLIST of the matched element, else -1 if it
+ * does not match any element or -2 if it is ambiguous (is a prefix of more
+ * than one element).
+ */
+static int
+argmatch(const char *arg, const char **optlist)
+{
+	int	i;	/* Temporary index in OPTLIST. */
+	size_t	arglen;	/* Length of ARG. */
+	int	matchind = -1;	/* Index of first nonexact match. */
+	int	ambiguous = 0;	/* If nonzero, multiple nonexact match(es). */
+
+	arglen = strlen(arg);
+
+	/* Test all elements for either exact match or abbreviated matches.  */
+	for (i = 0; optlist[i]; i++) {
+		if (!strncmp(optlist[i], arg, arglen)) {
+			if (strlen(optlist[i]) == arglen)
+				/* Exact match found.  */
+				return i;
+			else if (matchind == -1)
+				/* First nonexact match found.  */
+				matchind = i;
+			else
+				/* Second nonexact match found.  */
+				ambiguous = 1;
+		}
+	}
+	if (ambiguous)
+		return -2;
+	else
+		return matchind;
+}
+
+/*
+ * Error reporting for argmatch. KIND is a description of the type of entity
+ * that was being matched. VALUE is the invalid value that was given. PROBLEM
+ * is the return value from argmatch.
+ */
+static void
+invalid_arg(const char *kind, const char *value, int problem)
+{
+	fprintf(stderr, "patch: ");
+	if (problem == -1)
+		fprintf(stderr, "invalid");
+	else			/* Assume -2. */
+		fprintf(stderr, "ambiguous");
+	fprintf(stderr, " %s `%s'\n", kind, value);
+}
+
+static const char *backup_args[] = {
+	"never", "simple", "nil", "existing", "t", "numbered", 0
+};
+
+static enum backup_type backup_types[] = {
+	simple, simple, numbered_existing,
+	numbered_existing, numbered, numbered
+};
+
+/*
+ * Return the type of backup indicated by VERSION. Unique abbreviations are
+ * accepted.
+ */
+enum backup_type
+get_version(const char *version)
+{
+	int	i;
+
+	if (version == NULL || *version == '\0')
+		return numbered_existing;
+	i = argmatch(version, backup_args);
+	if (i >= 0)
+		return backup_types[i];
+	invalid_arg("version control type", version, i);
+	exit(2);
+}
diff --git a/usr.bin/patch/backupfile.h b/usr.bin/patch/backupfile.h
new file mode 100644
index 0000000..7c20ddb
--- /dev/null
+++ b/usr.bin/patch/backupfile.h
@@ -0,0 +1,38 @@
+/*	$OpenBSD: backupfile.h,v 1.6 2003/07/28 18:35:36 otto Exp $	*/
+
+/*
+ * backupfile.h -- declarations for making Emacs style backup file names
+ * Copyright (C) 1990 Free Software Foundation, Inc.
+ * 
+ * This program is free software; you can redistribute it and/or modify it
+ * without restriction.
+ * 
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.
+ * 
+ */
+
+/* When to make backup files. */
+enum backup_type {
+	/* Never make backups. */
+	none,
+
+	/* Make simple backups of every file. */
+	simple,
+
+	/*
+	 * Make numbered backups of files that already have numbered backups,
+	 * and simple backups of the others.
+	 */
+	numbered_existing,
+
+	/* Make numbered backups of every file. */
+	numbered
+};
+
+extern enum backup_type backup_type;
+extern char	*simple_backup_suffix;
+
+char		*find_backup_file_name(const char *file);
+enum backup_type get_version(const char *version);
diff --git a/usr.bin/patch/common.h b/usr.bin/patch/common.h
index 42d6883..4101a57 100644
--- a/usr.bin/patch/common.h
+++ b/usr.bin/patch/common.h
@@ -1,61 +1,54 @@
-/* $Header: common.h,v 2.0 86/09/17 15:36:39 lwall Exp $
- *
- * $Log:	common.h,v $
- * Revision 2.0  86/09/17  15:36:39  lwall
- * Baseline for netwide release.
+/*	$OpenBSD: common.h,v 1.25 2003/10/31 20:20:45 millert Exp $	*/
+
+/*
+ * patch - a program to apply diffs to original files
+ * 
+ * Copyright 1986, Larry Wall
+ * 
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following condition is met:
+ * 1. Redistributions of source code must retain the above copyright notice,
+ * this condition and the following disclaimer.
  * 
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * 
+ * -C option added in 1998, original code by Marc Espie, based on FreeBSD
+ * behaviour
  */
 
-#define DEBUGGING
+#include <stdbool.h>
 
-#include "config.h"
-
-/* shut lint up about the following when return value ignored */
-
-#define Signal (void)signal
-#define Unlink (void)unlink
-#define Lseek (void)lseek
-#define Fseek (void)fseek
-#define Fstat (void)fstat
-#define Pclose (void)pclose
-#define Close (void)close
-#define Fclose (void)fclose
-#define Fflush (void)fflush
-#define Sprintf (void)sprintf
-#define Mktemp (void)mktemp
-#define Strcpy (void)strcpy
-#define Strcat (void)strcat
-
-#include <stdio.h>
-#include <assert.h>
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <ctype.h>
-#include <signal.h>
+#define DEBUGGING
 
 /* constants */
 
-#define TRUE (1)
-#define FALSE (0)
-
-#define MAXHUNKSIZE 100000		/* is this enough lines? */
-#define INITHUNKMAX 125			/* initial dynamic allocation size */
-#define MAXLINELEN 1024
+#define MAXHUNKSIZE 100000	/* is this enough lines? */
+#define INITHUNKMAX 125		/* initial dynamic allocation size */
+#define MAXLINELEN 8192
 #define BUFFERSIZE 1024
-#define ORIGEXT ".orig"
+
 #define SCCSPREFIX "s."
 #define GET "get -e %s"
+#define SCCSDIFF "get -p %s | diff - %s >/dev/null"
+
 #define RCSSUFFIX ",v"
 #define CHECKOUT "co -l %s"
+#define RCSDIFF "rcsdiff %s > /dev/null"
 
-/* handy definitions */
-
-#define Null(t) ((t)0)
-#define Nullch Null(char *)
-#define Nullfp Null(FILE *)
-#define Nulline Null(LINENUM)
+#define ORIGEXT ".orig"
+#define REJEXT ".rej"
 
-#define Ctl(ch) ((ch) & 037)
+/* handy definitions */
 
 #define strNE(s1,s2) (strcmp(s1, s2))
 #define strEQ(s1,s2) (!strcmp(s1, s2))
@@ -64,75 +57,58 @@
 
 /* typedefs */
 
-typedef char bool;
-typedef long LINENUM;			/* must be signed */
-typedef unsigned MEM;			/* what to feed malloc */
+typedef long    LINENUM;	/* must be signed */
 
 /* globals */
 
-EXT int Argc;				/* guess */
-EXT char **Argv;
-EXT int Argc_last;			/* for restarting plan_b */
-EXT char **Argv_last;
+extern int	filemode;
 
-EXT struct stat filestat;		/* file statistics area */
-EXT int filemode INIT(0644);
+extern char	buf[MAXLINELEN];/* general purpose buffer */
 
-EXT char buf[MAXLINELEN];		/* general purpose buffer */
-EXT FILE *ofp INIT(Nullfp);		/* output file pointer */
-EXT FILE *rejfp INIT(Nullfp);		/* reject file pointer */
-
-EXT bool using_plan_a INIT(TRUE);	/* try to keep everything in memory */
-EXT bool out_of_mem INIT(FALSE);	/* ran out of memory in plan a */
+extern bool	using_plan_a;	/* try to keep everything in memory */
+extern bool	out_of_mem;	/* ran out of memory in plan a */
 
 #define MAXFILEC 2
-EXT int filec INIT(0);			/* how many file arguments? */
-EXT char *filearg[MAXFILEC];
-EXT bool ok_to_create_file INIT(FALSE);
-EXT char *bestguess INIT(Nullch);	/* guess at correct filename */
-
-EXT char *outname INIT(Nullch);
-EXT char rejname[128];
 
-EXT char *origext INIT(Nullch);
+extern char	*filearg[MAXFILEC];
+extern bool	ok_to_create_file;
+extern char	*outname;
+extern char	*origprae;
 
-EXT char TMPOUTNAME[] INIT("/tmp/patchoXXXXXX");
-EXT char TMPINNAME[] INIT("/tmp/patchiXXXXXX");	/* might want /usr/tmp here */
-EXT char TMPREJNAME[] INIT("/tmp/patchrXXXXXX");
-EXT char TMPPATNAME[] INIT("/tmp/patchpXXXXXX");
-EXT bool toutkeep INIT(FALSE);
-EXT bool trejkeep INIT(FALSE);
+extern char	*TMPOUTNAME;
+extern char	*TMPINNAME;
+extern char	*TMPREJNAME;
+extern char	*TMPPATNAME;
+extern bool	toutkeep;
+extern bool	trejkeep;
 
-EXT LINENUM last_offset INIT(0);
 #ifdef DEBUGGING
-EXT int debug INIT(0);
+extern int	debug;
 #endif
-EXT LINENUM maxfuzz INIT(2);
-EXT bool force INIT(FALSE);
-EXT bool verbose INIT(TRUE);
-EXT bool reverse INIT(FALSE);
-EXT bool noreverse INIT(FALSE);
-EXT bool skip_rest_of_patch INIT(FALSE);
-EXT int strippath INIT(957);
-EXT bool canonicalize INIT(FALSE);
+
+extern bool	force;
+extern bool	batch;
+extern bool	verbose;
+extern bool	reverse;
+extern bool	noreverse;
+extern bool	skip_rest_of_patch;
+extern int	strippath;
+extern bool	canonicalize;
+/* TRUE if -C was specified on command line.  */
+extern bool	check_only;
+extern bool	warn_on_invalid_line;
+extern bool	last_line_missing_eol;
+
 
 #define CONTEXT_DIFF 1
 #define NORMAL_DIFF 2
 #define ED_DIFF 3
 #define NEW_CONTEXT_DIFF 4
-EXT int diff_type INIT(0);
-
-EXT bool do_defines INIT(FALSE);	/* patch using ifdef, ifndef, etc. */
-EXT char if_defined[128];		/* #ifdef xyzzy */
-EXT char not_defined[128];		/* #ifndef xyzzy */
-EXT char else_defined[] INIT("#else\n");/* #else */
-EXT char end_defined[128];		/* #endif xyzzy */
-
-EXT char *revision INIT(Nullch);	/* prerequisite revision, if any */
-
-char *malloc();
-char *realloc();
-char *strcpy();
-char *strcat();
-long atol();
-char *mktemp();
+#define UNI_DIFF 5
+
+extern int	diff_type;
+extern char	*revision;	/* prerequisite revision, if any */
+extern LINENUM	input_lines;	/* how long is input file in lines */
+
+extern int	posix;
+
diff --git a/usr.bin/patch/inp.c b/usr.bin/patch/inp.c
index a3eeb90..3326843 100644
--- a/usr.bin/patch/inp.c
+++ b/usr.bin/patch/inp.c
@@ -1,313 +1,473 @@
-/* $Header: inp.c,v 2.0 86/09/17 15:37:02 lwall Exp $
- *
- * $Log:	inp.c,v $
- * Revision 2.0  86/09/17  15:37:02  lwall
- * Baseline for netwide release.
+/*	$OpenBSD: inp.c,v 1.31 2003/12/08 22:44:18 mickey Exp $	*/
+
+/*
+ * patch - a program to apply diffs to original files
+ * 
+ * Copyright 1986, Larry Wall
+ * 
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following condition is met:
+ * 1. Redistributions of source code must retain the above copyright notice,
+ * this condition and the following disclaimer.
  * 
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * 
+ * -C option added in 1998, original code by Marc Espie, based on FreeBSD
+ * behaviour
  */
 
-#include "EXTERN.h"
+#ifndef lint
+static const char     rcsid[] = "$OpenBSD: inp.c,v 1.31 2003/12/08 22:44:18 mickey Exp $";
+#endif /* not lint */
+
+#include <sys/types.h>
+#include <sys/file.h>
+#include <sys/stat.h>
+#include <sys/mman.h>
+
+#include <ctype.h>
+#include <libgen.h>
+#include <limits.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
 #include "common.h"
 #include "util.h"
 #include "pch.h"
-#include "INTERN.h"
 #include "inp.h"
 
+
 /* Input-file-with-indexable-lines abstract type */
 
-static long i_size;			/* size of the input file */
-static char *i_womp;			/* plan a buffer for entire file */
-static char **i_ptr;			/* pointers to lines in i_womp */
+static off_t	i_size;		/* size of the input file */
+static char	*i_womp;	/* plan a buffer for entire file */
+static char	**i_ptr;	/* pointers to lines in i_womp */
 
-static int tifd = -1;			/* plan b virtual string array */
-static char *tibuf[2];			/* plan b buffers */
-static LINENUM tiline[2] = {-1, -1};	/* 1st line in each buffer */
-static LINENUM lines_per_buf;		/* how many lines per buffer */
-static int tireclen;			/* length of records in tmp file */
+static int	tifd = -1;	/* plan b virtual string array */
+static char	*tibuf[2];	/* plan b buffers */
+static LINENUM	tiline[2] = {-1, -1};	/* 1st line in each buffer */
+static LINENUM	lines_per_buf;	/* how many lines per buffer */
+static int	tireclen;	/* length of records in tmp file */
+
+static bool	rev_in_string(const char *);
+static bool	reallocate_lines(size_t *);
+
+/* returns false if insufficient memory */
+static bool	plan_a(const char *);
+
+static void	plan_b(const char *);
 
 /* New patch--prepare to edit another file. */
 
 void
-re_input()
+re_input(void)
 {
-    if (using_plan_a) {
-	i_size = 0;
-#ifndef lint
-	if (i_ptr != Null(char**))
-	    free((char *)i_ptr);
-#endif
-	if (i_womp != Nullch)
-	    free(i_womp);
-	i_womp = Nullch;
-	i_ptr = Null(char **);
-    }
-    else {
-	using_plan_a = TRUE;		/* maybe the next one is smaller */
-	Close(tifd);
-	tifd = -1;
-	free(tibuf[0]);
-	free(tibuf[1]);
-	tibuf[0] = tibuf[1] = Nullch;
-	tiline[0] = tiline[1] = -1;
-	tireclen = 0;
-    }
+	if (using_plan_a) {
+		i_size = 0;
+		free(i_ptr);
+		i_ptr = NULL;
+		if (i_womp != NULL) {
+			munmap(i_womp, i_size);
+			i_womp = NULL;
+		}
+	} else {
+		using_plan_a = true;	/* maybe the next one is smaller */
+		close(tifd);
+		tifd = -1;
+		free(tibuf[0]);
+		free(tibuf[1]);
+		tibuf[0] = tibuf[1] = NULL;
+		tiline[0] = tiline[1] = -1;
+		tireclen = 0;
+	}
 }
 
 /* Constuct the line index, somehow or other. */
 
 void
-scan_input(filename)
-char *filename;
+scan_input(const char *filename)
 {
-    if (!plan_a(filename))
-	plan_b(filename);
-    if (verbose) {
-	say3("Patching file %s using Plan %s...\n", filename,
-	  (using_plan_a ? "A" : "B") );
-    }
+	if (!plan_a(filename))
+		plan_b(filename);
+	if (verbose) {
+		say("Patching file %s using Plan %s...\n", filename,
+		    (using_plan_a ? "A" : "B"));
+	}
+}
+
+static bool
+reallocate_lines(size_t *lines_allocated)
+{
+	char	**p;
+	size_t	new_size;
+
+	new_size = *lines_allocated * 3 / 2;
+	p = realloc(i_ptr, (new_size + 2) * sizeof(char *));
+	if (p == NULL) {	/* shucks, it was a near thing */
+		munmap(i_womp, i_size);
+		i_womp = NULL;
+		free(i_ptr);
+		i_ptr = NULL;
+		*lines_allocated = 0;
+		return false;
+	}
+	*lines_allocated = new_size;
+	i_ptr = p;
+	return true;
 }
 
 /* Try keeping everything in memory. */
 
-bool
-plan_a(filename)
-char *filename;
+static bool
+plan_a(const char *filename)
 {
-    int ifd;
-    Reg1 char *s;
-    Reg2 LINENUM iline;
-
-    if (ok_to_create_file && stat(filename, &filestat) < 0) {
-	if (verbose)
-	    say2("(Creating file %s...)\n",filename);
-	makedirs(filename, TRUE);
-	close(creat(filename, 0666));
-    }
-    if (stat(filename, &filestat) < 0) {
-	Sprintf(buf, "RCS/%s%s", filename, RCSSUFFIX);
-	if (stat(buf, &filestat) >= 0 || stat(buf+4, &filestat) >= 0) {
-	    Sprintf(buf, CHECKOUT, filename);
-	    if (verbose)
-		say2("Can't find %s--attempting to check it out from RCS.\n",
-		    filename);
-	    if (system(buf) || stat(filename, &filestat))
-		fatal2("Can't check out %s.\n", filename);
-	}
-	else {
-	    Sprintf(buf, "SCCS/%s%s", SCCSPREFIX, filename);
-	    if (stat(buf, &filestat) >= 0 || stat(buf+5, &filestat) >= 0) {
-		Sprintf(buf, GET, filename);
-		if (verbose)
-		    say2("Can't find %s--attempting to get it from SCCS.\n",
-			filename);
-		if (system(buf) || stat(filename, &filestat))
-		    fatal2("Can't get %s.\n", filename);
-	    }
-	    else
-		fatal2("Can't find %s.\n", filename);
-	}
-    }
-    filemode = filestat.st_mode;
-    if ((filemode & S_IFMT) & ~S_IFREG)
-	fatal2("%s is not a normal file--can't patch.\n", filename);
-    i_size = filestat.st_size;
-    if (out_of_mem) {
-	set_hunkmax();		/* make sure dynamic arrays are allocated */
-	out_of_mem = FALSE;
-	return FALSE;			/* force plan b because plan a bombed */
-    }
-#ifdef lint
-    i_womp = Nullch;
-#else
-    i_womp = malloc((MEM)(i_size+2));	/* lint says this may alloc less than */
-					/* i_size, but that's okay, I think. */
-#endif
-    if (i_womp == Nullch)
-	return FALSE;
-    if ((ifd = open(filename, 0)) < 0)
-	fatal2("Can't open file %s\n", filename);
-#ifndef lint
-    if (read(ifd, i_womp, (int)i_size) != i_size) {
-	Close(ifd);	/* probably means i_size > 15 or 16 bits worth */
-	free(i_womp);	/* at this point it doesn't matter if i_womp was */
-	return FALSE;	/*   undersized. */
-    }
-#endif
-    Close(ifd);
-    if (i_size && i_womp[i_size-1] != '\n')
-	i_womp[i_size++] = '\n';
-    i_womp[i_size] = '\0';
-
-    /* count the lines in the buffer so we know how many pointers we need */
-
-    iline = 0;
-    for (s=i_womp; *s; s++) {
-	if (*s == '\n')
-	    iline++;
-    }
-#ifdef lint
-    i_ptr = Null(char**);
-#else
-    i_ptr = (char **)malloc((MEM)((iline + 2) * sizeof(char *)));
+	int		ifd, statfailed;
+	char		*p, *s, lbuf[MAXLINELEN];
+	LINENUM		iline;
+	struct stat	filestat;
+	off_t		i;
+	ptrdiff_t	sz;
+	size_t		lines_allocated;
+
+#ifdef DEBUGGING
+	if (debug & 8)
+		return false;
 #endif
-    if (i_ptr == Null(char **)) {	/* shucks, it was a near thing */
-	free((char *)i_womp);
-	return FALSE;
-    }
-    
-    /* now scan the buffer and build pointer array */
-
-    iline = 1;
-    i_ptr[iline] = i_womp;
-    for (s=i_womp; *s; s++) {
-	if (*s == '\n')
-	    i_ptr[++iline] = s+1;	/* these are NOT null terminated */
-    }
-    input_lines = iline - 1;
-
-    /* now check for revision, if any */
-
-    if (revision != Nullch) { 
-	if (!rev_in_string(i_womp)) {
-	    if (force) {
+
+	if (filename == NULL || *filename == '\0')
+		return false;
+
+	statfailed = stat(filename, &filestat);
+	if (statfailed && ok_to_create_file) {
 		if (verbose)
-		    say2("\
-Warning: this file doesn't appear to be the %s version--patching anyway.\n",
-			revision);
-	    }
-	    else {
-		ask2("\
-This file doesn't appear to be the %s version--patch anyway? [n] ",
-		    revision);
-	    if (*buf != 'y')
-		fatal1("Aborted.\n");
-	    }
+			say("(Creating file %s...)\n", filename);
+
+		/*
+		 * in check_patch case, we still display `Creating file' even
+		 * though we're not. The rule is that -C should be as similar
+		 * to normal patch behavior as possible
+		 */
+		if (check_only)
+			return true;
+		makedirs(filename, true);
+		close(creat(filename, 0666));
+		statfailed = stat(filename, &filestat);
+	}
+	if (statfailed && check_only)
+		fatal("%s not found, -C mode, can't probe further\n", filename);
+	/* For nonexistent or read-only files, look for RCS or SCCS versions.  */
+	if (statfailed ||
+	    /* No one can write to it.  */
+	    (filestat.st_mode & 0222) == 0 ||
+	    /* I can't write to it.  */
+	    ((filestat.st_mode & 0022) == 0 && filestat.st_uid != getuid())) {
+		char	*cs = NULL, *filebase, *filedir;
+		struct stat	cstat;
+
+		filebase = basename(filename);
+		filedir = dirname(filename);
+
+		/* Leave room in lbuf for the diff command.  */
+		s = lbuf + 20;
+
+#define try(f, a1, a2, a3) \
+	(snprintf(s, sizeof lbuf - 20, f, a1, a2, a3), stat(s, &cstat) == 0)
+
+		if (try("%s/RCS/%s%s", filedir, filebase, RCSSUFFIX) ||
+		    try("%s/RCS/%s%s", filedir, filebase, "") ||
+		    try("%s/%s%s", filedir, filebase, RCSSUFFIX)) {
+			snprintf(buf, sizeof buf, CHECKOUT, filename);
+			snprintf(lbuf, sizeof lbuf, RCSDIFF, filename);
+			cs = "RCS";
+		} else if (try("%s/SCCS/%s%s", filedir, SCCSPREFIX, filebase) ||
+		    try("%s/%s%s", filedir, SCCSPREFIX, filebase)) {
+			snprintf(buf, sizeof buf, GET, s);
+			snprintf(lbuf, sizeof lbuf, SCCSDIFF, s, filename);
+			cs = "SCCS";
+		} else if (statfailed)
+			fatal("can't find %s\n", filename);
+		/*
+		 * else we can't write to it but it's not under a version
+		 * control system, so just proceed.
+		 */
+		if (cs) {
+			if (!statfailed) {
+				if ((filestat.st_mode & 0222) != 0)
+					/* The owner can write to it.  */
+					fatal("file %s seems to be locked "
+					    "by somebody else under %s\n",
+					    filename, cs);
+				/*
+				 * It might be checked out unlocked.  See if
+				 * it's safe to check out the default version
+				 * locked.
+				 */
+				if (verbose)
+					say("Comparing file %s to default "
+					    "%s version...\n",
+					    filename, cs);
+				if (system(lbuf))
+					fatal("can't check out file %s: "
+					    "differs from default %s version\n",
+					    filename, cs);
+			}
+			if (verbose)
+				say("Checking out file %s from %s...\n",
+				    filename, cs);
+			if (system(buf) || stat(filename, &filestat))
+				fatal("can't check out file %s from %s\n",
+				    filename, cs);
+		}
+	}
+	filemode = filestat.st_mode;
+	if (!S_ISREG(filemode))
+		fatal("%s is not a normal file--can't patch\n", filename);
+	i_size = filestat.st_size;
+	if (out_of_mem) {
+		set_hunkmax();	/* make sure dynamic arrays are allocated */
+		out_of_mem = false;
+		return false;	/* force plan b because plan a bombed */
 	}
-	else if (verbose)
-	    say2("Good.  This file appears to be the %s version.\n",
-		revision);
-    }
-    return TRUE;			/* plan a will work */
+	if (i_size > SIZE_MAX) {
+		say("block too large to mmap\n");
+		return false;
+	}
+	if ((ifd = open(filename, O_RDONLY)) < 0)
+		pfatal("can't open file %s", filename);
+
+	i_womp = mmap(NULL, i_size, PROT_READ, MAP_PRIVATE, ifd, 0);
+	if (i_womp == MAP_FAILED) {
+		perror("mmap failed");
+		i_womp = NULL;
+		close(ifd);
+		return false;
+	}
+
+	close(ifd);
+	if (i_size)
+		madvise(i_womp, i_size, MADV_SEQUENTIAL);
+
+	/* estimate the number of lines */
+	lines_allocated = i_size / 25;
+	if (lines_allocated < 100)
+		lines_allocated = 100;
+
+	if (!reallocate_lines(&lines_allocated)) 
+		return false;
+
+	/* now scan the buffer and build pointer array */
+	iline = 1;
+	i_ptr[iline] = i_womp;
+	/* test for NUL too, to maintain the behavior of the original code */
+	for (s = i_womp, i = 0; i < i_size && *s != '\0'; s++, i++) {
+		if (*s == '\n') {
+			if (iline == lines_allocated) {
+				if (!reallocate_lines(&lines_allocated))
+					return false;
+			}
+			/* these are NOT NUL terminated */
+			i_ptr[++iline] = s + 1;
+		}
+	}
+	/* if the last line contains no EOL, append one */
+	if (i_size > 0 && i_womp[i_size - 1] != '\n') {
+		last_line_missing_eol = true;
+		/* fix last line */
+		sz = s - i_ptr[iline];
+		p = malloc(sz + 1);
+		if (p == NULL) {
+			free(i_ptr);
+			i_ptr = NULL;
+			munmap(i_womp, i_size);
+			i_womp = NULL;
+			return false;
+		}
+
+		memcpy(p, i_ptr[iline], sz);
+		p[sz] = '\n';
+		i_ptr[iline] = p;
+		/* count the extra line and make it point to some valid mem */
+		i_ptr[++iline] = "";
+	} else
+		last_line_missing_eol = false;
+
+	input_lines = iline - 1;
+
+	/* now check for revision, if any */
+
+	if (revision != NULL) {
+		if (!rev_in_string(i_womp)) {
+			if (force) {
+				if (verbose)
+					say("Warning: this file doesn't appear "
+					    "to be the %s version--patching anyway.\n",
+					    revision);
+			} else if (batch) {
+				fatal("this file doesn't appear to be the "
+				    "%s version--aborting.\n",
+				    revision);
+			} else {
+				ask("This file doesn't appear to be the "
+				    "%s version--patch anyway? [n] ",
+				    revision);
+				if (*buf != 'y')
+					fatal("aborted\n");
+			}
+		} else if (verbose)
+			say("Good.  This file appears to be the %s version.\n",
+			    revision);
+	}
+	return true;		/* plan a will work */
 }
 
 /* Keep (virtually) nothing in memory. */
 
-void
-plan_b(filename)
-char *filename;
+static void
+plan_b(const char *filename)
 {
-    Reg3 FILE *ifp;
-    Reg1 int i = 0;
-    Reg2 int maxlen = 1;
-    Reg4 bool found_revision = (revision == Nullch);
-
-    using_plan_a = FALSE;
-    if ((ifp = fopen(filename, "r")) == Nullfp)
-	fatal2("Can't open file %s\n", filename);
-    if ((tifd = creat(TMPINNAME, 0666)) < 0)
-	fatal2("Can't open file %s\n", TMPINNAME);
-    while (fgets(buf, sizeof buf, ifp) != Nullch) {
-	if (revision != Nullch && !found_revision && rev_in_string(buf))
-	    found_revision = TRUE;
-	if ((i = strlen(buf)) > maxlen)
-	    maxlen = i;			/* find longest line */
-    }
-    if (revision != Nullch) {
-	if (!found_revision) {
-	    if (force) {
-		if (verbose)
-		    say2("\
-Warning: this file doesn't appear to be the %s version--patching anyway.\n",
-			revision);
-	    }
-	    else {
-		ask2("\
-This file doesn't appear to be the %s version--patch anyway? [n] ",
-		    revision);
-		if (*buf != 'y')
-		    fatal1("Aborted.\n");
-	    }
+	FILE	*ifp;
+	int	i = 0, j, maxlen = 1;
+	char	*p;
+	bool	found_revision = (revision == NULL);
+
+	using_plan_a = false;
+	if ((ifp = fopen(filename, "r")) == NULL)
+		pfatal("can't open file %s", filename);
+	(void) unlink(TMPINNAME);
+	if ((tifd = open(TMPINNAME, O_EXCL | O_CREAT | O_WRONLY, 0666)) < 0)
+		pfatal("can't open file %s", TMPINNAME);
+	while (fgets(buf, sizeof buf, ifp) != NULL) {
+		if (revision != NULL && !found_revision && rev_in_string(buf))
+			found_revision = true;
+		if ((i = strlen(buf)) > maxlen)
+			maxlen = i;	/* find longest line */
 	}
-	else if (verbose)
-	    say2("Good.  This file appears to be the %s version.\n",
-		revision);
-    }
-    Fseek(ifp, 0L, 0);		/* rewind file */
-    lines_per_buf = BUFFERSIZE / maxlen;
-    tireclen = maxlen;
-    tibuf[0] = malloc((MEM)(BUFFERSIZE + 1));
-    tibuf[1] = malloc((MEM)(BUFFERSIZE + 1));
-    if (tibuf[1] == Nullch)
-	fatal1("Can't seem to get enough memory.\n");
-    for (i=1; ; i++) {
-	if (! (i % lines_per_buf))	/* new block */
-	    if (write(tifd, tibuf[0], BUFFERSIZE) < BUFFERSIZE)
-		fatal1("patch: can't write temp file.\n");
-	if (fgets(tibuf[0] + maxlen * (i%lines_per_buf), maxlen + 1, ifp)
-	  == Nullch) {
-	    input_lines = i - 1;
-	    if (i % lines_per_buf)
-		if (write(tifd, tibuf[0], BUFFERSIZE) < BUFFERSIZE)
-		    fatal1("patch: can't write temp file.\n");
-	    break;
+	last_line_missing_eol = i > 0 && buf[i - 1] != '\n';
+	if (last_line_missing_eol && maxlen == i)
+		maxlen++;
+		
+	if (revision != NULL) {
+		if (!found_revision) {
+			if (force) {
+				if (verbose)
+					say("Warning: this file doesn't appear "
+					    "to be the %s version--patching anyway.\n",
+					    revision);
+			} else if (batch) {
+				fatal("this file doesn't appear to be the "
+				    "%s version--aborting.\n",
+				    revision);
+			} else {
+				ask("This file doesn't appear to be the %s "
+				    "version--patch anyway? [n] ",
+				    revision);
+				if (*buf != 'y')
+					fatal("aborted\n");
+			}
+		} else if (verbose)
+			say("Good.  This file appears to be the %s version.\n",
+			    revision);
 	}
-    }
-    Fclose(ifp);
-    Close(tifd);
-    if ((tifd = open(TMPINNAME, 0)) < 0) {
-	fatal2("Can't reopen file %s\n", TMPINNAME);
-    }
+	fseek(ifp, 0L, SEEK_SET);	/* rewind file */
+	lines_per_buf = BUFFERSIZE / maxlen;
+	tireclen = maxlen;
+	tibuf[0] = malloc(BUFFERSIZE + 1);
+	if (tibuf[0] == NULL)
+		fatal("out of memory\n");
+	tibuf[1] = malloc(BUFFERSIZE + 1);
+	if (tibuf[1] == NULL)
+		fatal("out of memory\n");
+	for (i = 1;; i++) {
+		p = tibuf[0] + maxlen * (i % lines_per_buf);
+		if (i % lines_per_buf == 0)	/* new block */
+			if (write(tifd, tibuf[0], BUFFERSIZE) < BUFFERSIZE)
+				pfatal("can't write temp file");
+		if (fgets(p, maxlen + 1, ifp) == NULL) {
+			input_lines = i - 1;
+			if (i % lines_per_buf != 0)
+				if (write(tifd, tibuf[0], BUFFERSIZE) < BUFFERSIZE)
+					pfatal("can't write temp file");
+			break;
+		}
+		j = strlen(p);
+		/* These are '\n' terminated strings, so no need to add a NUL */
+		if (j == 0 || p[j - 1] != '\n')
+			p[j] = '\n';
+	}
+	fclose(ifp);
+	close(tifd);
+	if ((tifd = open(TMPINNAME, O_RDONLY)) < 0)
+		pfatal("can't reopen file %s", TMPINNAME);
 }
 
-/* Fetch a line from the input file, \n terminated, not necessarily \0. */
-
+/*
+ * Fetch a line from the input file, \n terminated, not necessarily \0.
+ */
 char *
-ifetch(line,whichbuf)
-Reg1 LINENUM line;
-int whichbuf;				/* ignored when file in memory */
+ifetch(LINENUM line, int whichbuf)
 {
-    if (line < 1 || line > input_lines)
-	return "";
-    if (using_plan_a)
-	return i_ptr[line];
-    else {
-	LINENUM offline = line % lines_per_buf;
-	LINENUM baseline = line - offline;
-
-	if (tiline[0] == baseline)
-	    whichbuf = 0;
-	else if (tiline[1] == baseline)
-	    whichbuf = 1;
+	if (line < 1 || line > input_lines) {
+		if (warn_on_invalid_line) {
+			say("No such line %ld in input file, ignoring\n", line);
+			warn_on_invalid_line = false;
+		}
+		return NULL;
+	}
+	if (using_plan_a)
+		return i_ptr[line];
 	else {
-	    tiline[whichbuf] = baseline;
-#ifndef lint		/* complains of long accuracy */
-	    Lseek(tifd, (off_t)baseline / lines_per_buf * BUFFERSIZE, 0);
-#endif
-	    if (read(tifd, tibuf[whichbuf], BUFFERSIZE) < 0)
-		fatal2("Error reading tmp file %s.\n", TMPINNAME);
+		LINENUM	offline = line % lines_per_buf;
+		LINENUM	baseline = line - offline;
+
+		if (tiline[0] == baseline)
+			whichbuf = 0;
+		else if (tiline[1] == baseline)
+			whichbuf = 1;
+		else {
+			tiline[whichbuf] = baseline;
+
+			lseek(tifd, (off_t) (baseline / lines_per_buf *
+			    BUFFERSIZE), SEEK_SET);
+
+			if (read(tifd, tibuf[whichbuf], BUFFERSIZE) < 0)
+				pfatal("error reading tmp file %s", TMPINNAME);
+		}
+		return tibuf[whichbuf] + (tireclen * offline);
 	}
-	return tibuf[whichbuf] + (tireclen*offline);
-    }
 }
 
-/* True if the string argument contains the revision number we want. */
-
-bool
-rev_in_string(string)
-char *string;
+/*
+ * True if the string argument contains the revision number we want.
+ */
+static bool
+rev_in_string(const char *string)
 {
-    Reg1 char *s;
-    Reg2 int patlen;
-
-    if (revision == Nullch)
-	return TRUE;
-    patlen = strlen(revision);
-    for (s = string; *s; s++) {
-	if (isspace(*s) && strnEQ(s+1, revision, patlen) && 
-		isspace(s[patlen+1] )) {
-	    return TRUE;
+	const char	*s;
+	int		patlen;
+
+	if (revision == NULL)
+		return true;
+	patlen = strlen(revision);
+	if (strnEQ(string, revision, patlen) && isspace(string[patlen]))
+		return true;
+	for (s = string; *s; s++) {
+		if (isspace(*s) && strnEQ(s + 1, revision, patlen) &&
+		    isspace(s[patlen + 1])) {
+			return true;
+		}
 	}
-    }
-    return FALSE;
+	return false;
 }
-
diff --git a/usr.bin/patch/inp.h b/usr.bin/patch/inp.h
index c6d2a91..aa66208 100644
--- a/usr.bin/patch/inp.h
+++ b/usr.bin/patch/inp.h
@@ -1,18 +1,31 @@
-/* $Header: inp.h,v 2.0 86/09/17 15:37:25 lwall Exp $
- *
- * $Log:	inp.h,v $
- * Revision 2.0  86/09/17  15:37:25  lwall
- * Baseline for netwide release.
+/*	$OpenBSD: inp.h,v 1.8 2003/08/15 08:00:51 otto Exp $	*/
+
+/*
+ * patch - a program to apply diffs to original files
+ * 
+ * Copyright 1986, Larry Wall
+ * 
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following condition is met:
+ * 1. Redistributions of source code must retain the above copyright notice,
+ * this condition and the following disclaimer.
  * 
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * 
+ * -C option added in 1998, original code by Marc Espie, based on FreeBSD
+ * behaviour
  */
 
-EXT LINENUM input_lines INIT(0);	/* how long is input file in lines */
-EXT LINENUM last_frozen_line INIT(0);	/* how many input lines have been */
-					/* irretractibly output */
-
-bool rev_in_string();
-void scan_input();
-bool plan_a();			/* returns false if insufficient memory */
-void plan_b();
-char *ifetch();
-
+void		re_input(void);
+void		scan_input(const char *);
+char		*ifetch(LINENUM, int);
diff --git a/usr.bin/patch/patch.1 b/usr.bin/patch/patch.1
index 3e4a12e..9d12b8b 100644
--- a/usr.bin/patch/patch.1
+++ b/usr.bin/patch/patch.1
@@ -1,130 +1,348 @@
-''' $Header: patch.man,v 2.0 86/09/17 15:39:09 lwall Exp $
-''' 
-''' $Log:	patch.man,v $
-''' Revision 2.0  86/09/17  15:39:09  lwall
-''' Baseline for netwide release.
-''' 
-''' Revision 1.4  86/08/01  19:23:22  lwall
-''' Documented -v, -p, -F.
-''' Added notes to patch senders.
-''' 
-''' Revision 1.3  85/03/26  15:11:06  lwall
-''' Frozen.
-''' 
-''' Revision 1.2.1.4  85/03/12  16:14:27  lwall
-''' Documented -p.
-''' 
-''' Revision 1.2.1.3  85/03/12  16:09:41  lwall
-''' Documented -D.
-''' 
-''' Revision 1.2.1.2  84/12/05  11:06:55  lwall
-''' Added -l switch, and noted bistability bug.
-''' 
-''' Revision 1.2.1.1  84/12/04  17:23:39  lwall
-''' Branch for sdcrdcf changes.
-''' 
-''' Revision 1.2  84/12/04  17:22:02  lwall
-''' Baseline version.
-''' 
-.de Sh
-.br
-.ne 5
-.PP
-\fB\\$1\fR
-.PP
-..
-.de Sp
-.if t .sp .5v
-.if n .sp
-..
-'''
-'''     Set up \*(-- to give an unbreakable dash;
-'''     string Tr holds user defined translation string.
-'''     Bell System Logo is used as a dummy character.
-'''
-.ie n \{\
-.tr \(bs-\*(Tr
-.ds -- \(bs-
-.if (\n(.H=4u)&(1m=24u) .ds -- \(bs\h'-12u'\(bs\h'-12u'-\" diablo 10 pitch
-.if (\n(.H=4u)&(1m=20u) .ds -- \(bs\h'-12u'\(bs\h'-8u'-\" diablo 12 pitch
-.ds L" ""
-.ds R" ""
-.ds L' '
-.ds R' '
-'br\}
-.el\{\
-.ds -- \(em\|
-.tr \*(Tr
-.ds L" ``
-.ds R" ''
-.ds L' `
-.ds R' '
-'br\}
-.TH PATCH 1 "June 30, 1993"
-.SH NAME
-patch \- a program for applying a diff file to an original
-.SH SYNOPSIS
-.B patch
-[options] orig patchfile [+ [options] orig]
-.sp
-but usually just
-.sp
-.B patch
-<patchfile
-.SH DESCRIPTION
-.I Patch
-will take a patch file containing any of the three forms of difference
+.\"	$OpenBSD: patch.1,v 1.17 2003/10/31 20:20:45 millert Exp $
+.\" Copyright 1986, Larry Wall
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following condition
+.\" is met:
+.\"  1. Redistributions of source code must retain the above copyright
+.\"     notice, this condition and the following disclaimer.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.
+.\"
+.Dd July 23, 2003
+.Dt PATCH 1
+.Os
+.Sh NAME
+.Nm patch
+.Nd apply a diff file to an original
+.Sh SYNOPSIS
+.Nm patch
+.Op Cm options
+.Op Ar origfile Op Ar patchfile
+.Nm patch
+.Pf \*(Lt Ar patchfile
+.Sh DESCRIPTION
+.Nm
+will take a patch file containing any of the four forms of difference
 listing produced by the
-.I diff
-program and apply those differences to an original file, producing a patched
-version.
-By default, the patched version is put in place of the original, with
-the original file backed up to the same name with the
-extension \*(L".orig\*(R", or as specified by the
-.B -b
-switch.
-You may also specify where you want the output to go with a
-.B -o
-switch.
+.Xr diff 1
+program and apply those differences to an original file,
+producing a patched version.
 If
-.I patchfile
-is omitted, or is a hyphen, the patch will be read from standard input.
-.PP
-Upon startup, patch will attempt to determine the type of the diff listing,
-unless over-ruled by a
-.BR -c ,
-.BR -e ,
+.Ar patchfile
+is omitted, or is a hyphen, the patch will be read from the standard input.
+.Pp
+.Nm
+will attempt to determine the type of the diff listing, unless over-ruled by a
+.Fl c ,
+.Fl e ,
+.Fl n ,
 or
-.B -n
-switch.
-Context diffs and normal diffs are applied by the
-.I patch
-program itself, while ed diffs are simply fed to the
-.I ed
+.Fl u
+option.
+Context diffs (old-style, new-style, and unified) and
+normal diffs are applied directly by the
+.Nm
+program itself, whereas ed diffs are simply fed to the
+.Xr ed 1
 editor via a pipe.
-.PP
-.I Patch
+.Pp
+If the
+.Ar patchfile
+contains more than one patch,
+.Nm
+will try to apply each of them as if they came from separate patch files.
+This means, among other things, that it is assumed that the name of the file
+to patch must be determined for each diff listing, and that the garbage before
+each diff listing will be examined for interesting things such as file names
+and revision level (see the section on
+.Sx Filename Determination
+below).
+.Pp
+The options are as follows:
+.Bl -tag -width Ds
+.It Fl b , Fl Fl backup
+Save a backup copy of the file before it is modified.
+By default the original file is saved with a backup extension of
+.Qq .orig
+unless the file already has a numbered backup, in which case a numbered
+backup is made.
+This is equivalent to specifying
+.Qo Fl V Ar existing Qc .
+This option is currently the default but that will change in a future release.
+.It Fl B , Fl Fl prefix
+Causes the next argument to be interpreted as a prefix to the backup file
+name.
+If this argument is specified, any argument to
+.Fl z
+will be ignored.
+.It Fl c , Fl Fl context
+Forces
+.Nm
+to interpret the patch file as a context diff.
+.It Fl C , Fl Fl check
+Checks that the patch would apply cleanly, but does not modify anything.
+.It Fl d , Fl Fl directory
+Causes
+.Nm
+to interpret the next argument as a directory, and
+.Xr cd 1
+to it before doing anything else.
+.It Fl D , Fl Fl ifdef
+Causes
+.Nm
+to use the
+.Qq #ifdef...#endif
+construct to mark changes.
+The argument following will be used as the differentiating symbol.
+Note that, unlike the C compiler, there must be a space between the
+.Fl D
+and the argument.
+.It Fl e , Fl Fl ed
+Forces
+.Nm
+to interpret the patch file as an
+.Xr ed 1
+script.
+.It Fl E , Fl Fl remove-empty-files
+Causes
+.Nm
+to remove output files that are empty after the patches have been applied.
+This option is useful when applying patches that create or remove files.
+.It Fl f , Fl Fl force
+Forces
+.Nm
+to assume that the user knows exactly what he or she is doing, and to not
+ask any questions.
+It assumes the following:
+skip patches for which a file to patch can't be found;
+patch files even though they have the wrong version for the
+.Qq Prereq:
+line in the patch;
+and assume that patches are not reversed even if they look like they are.
+This option does not suppress commentary; use
+.Fl s
+for that.
+.It Xo
+.Fl F Ns Aq Ar number ,
+.Fl Fl fuzz Aq Ar number
+.Xc
+Sets the maximum fuzz factor.
+This option only applies to context diffs, and causes
+.Nm
+to ignore up to that many lines in looking for places to install a hunk.
+Note that a larger fuzz factor increases the odds of a faulty patch.
+The default fuzz factor is 2, and it may not be set to more than
+the number of lines of context in the context diff, ordinarily 3.
+.It Fl i , Fl Fl input
+Causes the next argument to be interpreted as the input file name
+(i.e. a patchfile).
+This option may be specified multiple times.
+.It Fl l , Fl Fl ignore-whitespace
+Causes the pattern matching to be done loosely, in case the tabs and
+spaces have been munged in your input file.
+Any sequence of whitespace in the pattern line will match any sequence
+in the input file.
+Normal characters must still match exactly.
+Each line of the context must still match a line in the input file.
+.It Fl n , Fl Fl normal
+Forces
+.Nm
+to interpret the patch file as a normal diff.
+.It Fl N , Fl Fl forward
+Causes
+.Nm
+to ignore patches that it thinks are reversed or already applied.
+See also
+.Fl R .
+.It Fl o , Fl Fl output
+Causes the next argument to be interpreted as the output file name.
+.It Xo
+.Fl p Ns Aq Ar number ,
+.Fl Fl strip Aq Ar number
+.Xc
+Sets the pathname strip count,
+which controls how pathnames found in the patch file are treated,
+in case you keep your files in a different directory than the person who sent
+out the patch.
+The strip count specifies how many slashes are to be stripped from
+the front of the pathname.
+(Any intervening directory names also go away.)
+For example, supposing the file name in the patch file was
+.Pa /u/howard/src/blurfl/blurfl.c :
+.Pp
+Setting
+.Fl p Ns Ar 0
+gives the entire pathname unmodified.
+.Pp
+.Fl p Ns Ar 1
+gives
+.Pp
+.D1 Pa u/howard/src/blurfl/blurfl.c
+.Pp
+without the leading slash.
+.Pp
+.Fl p Ns Ar 4
+gives
+.Pp
+.D1 Pa blurfl/blurfl.c
+.Pp
+Not specifying
+.Fl p
+at all just gives you
+.Pa blurfl.c ,
+unless all of the directories in the leading path
+.Pq Pa u/howard/src/blurfl
+exist and that path is relative,
+in which case you get the entire pathname unmodified.
+Whatever you end up with is looked for either in the current directory,
+or the directory specified by the
+.Fl d
+option.
+.It Fl r , Fl Fl reject-file
+Causes the next argument to be interpreted as the reject file name.
+.It Fl R , Fl Fl reverse
+Tells
+.Nm
+that this patch was created with the old and new files swapped.
+(Yes, I'm afraid that does happen occasionally, human nature being what it
+is.)
+.Nm
+will attempt to swap each hunk around before applying it.
+Rejects will come out in the swapped format.
+The
+.Fl R
+option will not work with ed diff scripts because there is too little
+information to reconstruct the reverse operation.
+.Pp
+If the first hunk of a patch fails,
+.Nm
+will reverse the hunk to see if it can be applied that way.
+If it can, you will be asked if you want to have the
+.Fl R
+option set.
+If it can't, the patch will continue to be applied normally.
+(Note: this method cannot detect a reversed patch if it is a normal diff
+and if the first command is an append (i.e. it should have been a delete)
+since appends always succeed, due to the fact that a null context will match
+anywhere.
+Luckily, most patches add or change lines rather than delete them, so most
+reversed normal diffs will begin with a delete, which will fail, triggering
+the heuristic.)
+.It Xo
+.Fl s , Fl Fl quiet ,
+.Fl Fl silent
+.Xc
+Makes
+.Nm
+do its work silently, unless an error occurs.
+.It Fl t , Fl Fl batch
+Similar to
+.Fl f ,
+in that it suppresses questions, but makes some different assumptions:
+skip patches for which a file to patch can't be found (the same as
+.Fl f ) ;
+skip patches for which the file has the wrong version for the
+.Qq Prereq:
+line in the patch;
+and assume that patches are reversed if they look like they are.
+.It Fl u , Fl Fl unified
+Forces
+.Nm
+to interpret the patch file as a unified context diff (a unidiff).
+.It Fl v , Fl Fl version
+Causes
+.Nm
+to print out its revision header and patch level.
+.It Fl V , Fl Fl version-control
+Causes the next argument to be interpreted as a method for creating
+backup file names.
+The type of backups made can also be given in the
+.Ev PATCH_VERSION_CONTROL
+or
+.Ev VERSION_CONTROL
+environment variables, which are overridden by this option.
+The
+.Fl B
+option overrides this option, causing the prefix to always be used for
+making backup file names.
+The values of the
+.Ev PATCH_VERSION_CONTROL
+and
+.Ev VERSION_CONTROL
+environment variables and the argument to the
+.Fl V
+option are like the GNU Emacs
+.Dq version-control
+variable; they also recognize synonyms that are more descriptive.
+The valid values are (unique abbreviations are accepted):
+.Bl -tag -width Ds -offset indent
+.It t , numbered
+Always make numbered backups.
+.It nil , existing
+Make numbered backups of files that already have them,
+simple backups of the others.
+.It never , simple
+Always make simple backups.
+.El
+.It Xo
+.Fl x Ns Aq Ar number ,
+.Fl Fl debug Aq Ar number
+.Xc
+Sets internal debugging flags, and is of interest only to
+.Nm
+patchers.
+.It Fl z , Fl Fl suffix
+Causes the next argument to be interpreted as the backup extension, to be
+used in place of
+.Qq .orig .
+.It Fl Fl posix
+Enables strict
+.St -p1003.2
+conformance, specifically:
+.Bl -enum
+.It
+Backup files are not created unless the
+.Fl b
+option is specified.
+.It
+If unspecified, the file name used is the first of the old, new and
+index files that exists.
+.El
+.El
+.Ss Patch Application
+.Nm
 will try to skip any leading garbage, apply the diff,
 and then skip any trailing garbage.
 Thus you could feed an article or message containing a
 diff listing to
-.IR patch ,
+.Nm patch ,
 and it should work.
 If the entire diff is indented by a consistent amount,
 this will be taken into account.
-.PP
+.Pp
 With context diffs, and to a lesser extent with normal diffs,
-.I patch
+.Nm
 can detect when the line numbers mentioned in the patch are incorrect,
 and will attempt to find the correct place to apply each hunk of the patch.
 As a first guess, it takes the line number mentioned for the hunk, plus or
 minus any offset used in applying the previous hunk.
 If that is not the correct place,
-.I patch
+.Nm
 will scan both forwards and backwards for a set of lines matching the context
 given in the hunk.
 First
-.I patch
+.Nm
 looks for a place where all lines of the context match.
 If no such place is found, and it's a context diff, and the maximum fuzz factor
 is set to 1 or more, then another scan takes place ignoring the first and last
@@ -132,315 +350,292 @@ line of context.
 If that fails, and the maximum fuzz factor is set to 2 or more,
 the first two and last two lines of context are ignored,
 and another scan is made.
-(The default maximum fuzz factor is 2.)
+.Pq The default maximum fuzz factor is 2.
+.Pp
 If
-.I patch
-cannot find a place to install that hunk of the patch, it will put the
-hunk out to a reject file, which normally is the name of the output file
-plus \*(L".rej\*(R".
+.Nm
+cannot find a place to install that hunk of the patch, it will put the hunk
+out to a reject file, which normally is the name of the output file plus
+.Qq .rej .
 (Note that the rejected hunk will come out in context diff form whether the
 input patch was a context diff or a normal diff.
 If the input was a normal diff, many of the contexts will simply be null.)
 The line numbers on the hunks in the reject file may be different than
 in the patch file: they reflect the approximate location patch thinks the
 failed hunks belong in the new file rather than the old one.
-.PP
+.Pp
 As each hunk is completed, you will be told whether the hunk succeeded or
 failed, and which line (in the new file)
-.I patch
+.Nm
 thought the hunk should go on.
-If this is different from the line number specified in the diff you will
-be told the offset.
+If this is different from the line number specified in the diff,
+you will be told the offset.
 A single large offset MAY be an indication that a hunk was installed in the
 wrong place.
 You will also be told if a fuzz factor was used to make the match, in which
 case you should also be slightly suspicious.
-.PP
+.Ss Filename Determination
 If no original file is specified on the command line,
-.I patch
+.Nm
 will try to figure out from the leading garbage what the name of the file
 to edit is.
-In the header of a context diff, the filename is found from lines beginning
-with \*(L"***\*(R" or \*(L"---\*(R", with the shortest name of an existing
-file winning.
-Only context diffs have lines like that, but if there is an \*(L"Index:\*(R"
-line in the leading garbage,
-.I patch
-will try to use the filename from that line.
-The context diff header takes precedence over an Index line.
-If no filename can be intuited from the leading garbage, you will be asked
-for the name of the file to patch.
-.PP
-(If the original file cannot be found, but a suitable SCCS or RCS file is
-handy,
-.I patch
-will attempt to get or check out the file.)
-.PP
-Additionally, if the leading garbage contains a \*(L"Prereq: \*(R" line,
-.I patch
+When checking a prospective file name, pathname components are stripped
+as specified by the
+.Fl p
+option and the file's existence and writability are checked relative
+to the current working directory (or the directory specified by the
+.Fl d
+option).
+.Pp
+If the diff is a context or unified diff,
+.Nm
+is able to determine the old and new file names from the diff header.
+For context diffs, the
+.Dq old
+file is specified in the line beginning with
+.Qq ***
+and the
+.Dq new
+file is specified in the line beginning with
+.Qq --- .
+For a unified diff, the
+.Dq old
+file is specified in the line beginning with
+.Qq ---
+and the
+.Dq new
+file is specified in the line beginning with
+.Qq +++ .
+If there is an
+.Qq Index:
+line in the leading garbage (regardless of the diff type),
+.Nm
+will use the file name from that line as the
+.Dq index
+file.
+.Pp
+.Nm
+will choose the file name by performing the following steps, with the first
+match used:
+.Bl -enum
+.It
+If
+.Nm
+is operating in strict
+.St -p1003.2
+mode, the first of the
+.Dq old ,
+.Dq new
+and
+.Dq index
+file names that exist is used.
+Otherwise,
+.Nm
+will examine either the
+.Dq old
+and
+.Dq new
+file names or, for a non-context diff, the
+.Dq index
+file name, and choose the file name with the fewest path components,
+the shortest basename, and the shortest total file name length (in that order).
+.It
+If no file exists,
+.Nm
+checks for the existence of the files in an SCCS or RCS directory
+(using the appropriate prefix or suffix) using the criteria specified
+above.
+If found,
+.Nm
+will attempt to get or check out the file.
+.It
+If no suitable file was found to patch, the patch file is a context or
+unified diff, and the old file was zero length, the new file name is
+created and used.
+.It
+If the file name still cannot be determined,
+.Nm
+will prompt the user for the file name to use.
+.El
+.Pp
+Additionally, if the leading garbage contains a
+.Qq Prereq:\ \&
+line,
+.Nm
 will take the first word from the prerequisites line (normally a version
 number) and check the input file to see if that word can be found.
 If not,
-.I patch
+.Nm
 will ask for confirmation before proceeding.
-.PP
+.Pp
 The upshot of all this is that you should be able to say, while in a news
 interface, the following:
-.Sp
-	| patch -d /usr/src/local/blurfl
-.Sp
+.Pp
+.Dl | patch -d /usr/src/local/blurfl
+.Pp
 and patch a file in the blurfl directory directly from the article containing
 the patch.
-.PP
-If the patch file contains more than one patch,
-.I patch
-will try to apply each of them as if they came from separate patch files.
-This means, among other things, that it is assumed that the name of the file
-to patch must be determined for each diff listing,
-and that the garbage before each diff listing will
-be examined for interesting things such as filenames and revision level, as
-mentioned previously.
-You can give switches (and another original file name) for the second and
-subsequent patches by separating the corresponding argument lists
-by a \*(L'+\*(R'.
-(The argument list for a second or subsequent patch may not specify a new
-patch file, however.)
-.PP
-.I Patch
-recognizes the following switches:
-.TP 5
-.B \-b
-causes the next argument to be interpreted as the backup extension, to be
-used in place of \*(L".orig\*(R".
-.TP 5
-.B \-c
-forces
-.I patch
-to interpret the patch file as a context diff.
-.TP 5
-.B \-d
-causes
-.I patch
-to interpret the next argument as a directory, and cd to it before doing
-anything else.
-.TP 5
-.B \-D
-causes
-.I patch
-to use the "#ifdef...#endif" construct to mark changes.
-The argument following will be used as the differentiating symbol.
-Note that, unlike the C compiler, there must be a space between the
-.B \-D
-and the argument.
-.TP 5
-.B \-e
-forces
-.I patch
-to interpret the patch file as an ed script.
-.TP 5
-.B \-f
-forces
-.I patch
-to assume that the user knows exactly what he or she is doing, and to not
-ask any questions.
-It does not suppress commentary, however.
-Use
-.B \-s
-for that.
-.TP 5
-.B \-F<number>
-sets the maximum fuzz factor.
-This switch only applied to context diffs, and causes
-.I patch
-to ignore up to that many lines in looking for places to install a hunk.
-Note that a larger fuzz factor increases the odds of a faulty patch.
-The default fuzz factor is 2, and it may not be set to more than
-the number of lines of context in the context diff, ordinarily 3.
-.TP 5
-.B \-l
-causes the pattern matching to be done loosely, in case the tabs and
-spaces have been munged in your input file.
-Any sequence of whitespace in the pattern line will match any sequence
-in the input file.
-Normal characters must still match exactly.
-Each line of the context must still match a line in the input file.
-.TP 5
-.B \-n
-forces
-.I patch
-to interpret the patch file as a normal diff.
-.TP 5
-.B \-N
-causes
-.I patch
-to ignore patches that it thinks are reversed or already applied.
-See also
-.B \-R .
-.TP 5
-.B \-o
-causes the next argument to be interpreted as the output file name.
-.TP 5
-.B \-p<number>
-sets the pathname strip count,
-which controls how pathnames found in the patch file are treated, in case
-the you keep your files in a different directory than the person who sent
-out the patch.
-The strip count specifies how many backslashes are to be stripped from
-the front of the pathname.
-(Any intervening directory names also go away.)
-For example, supposing the filename in the patch file was
-.sp
-	/u/howard/src/blurfl/blurfl.c
-.sp
-setting
-.B \-p
+.Ss Backup Files
+By default, the patched version is put in place of the original, with
+the original file backed up to the same name with the extension
+.Qq .orig ,
+or as specified by the
+.Fl B ,
+.Fl V ,
 or
-.B \-p0
-gives the entire pathname unmodified,
-.B \-p1
-gives
-.sp
-	u/howard/src/blurfl/blurfl.c
-.sp
-without the leading slash,
-.B \-p4
-gives
-.sp
-	blurfl/blurfl.c
-.sp
-and not specifying
-.B \-p
-at all just gives you "blurfl.c".
-Whatever you end up with is looked for either in the current directory,
-or the directory specified by the
-.B \-d
-switch.
-.TP 5
-.B \-r
-causes the next argument to be interpreted as the reject file name.
-.TP 5
-.B \-R
-tells
-.I patch
-that this patch was created with the old and new files swapped.
-(Yes, I'm afraid that does happen occasionally, human nature being what it
-is.)
-.I Patch
-will attempt to swap each hunk around before applying it.
-Rejects will come out in the swapped format.
-The
-.B \-R
-switch will not work with ed diff scripts because there is too little
-information to reconstruct the reverse operation.
-.Sp
-If the first hunk of a patch fails,
-.I patch
-will reverse the hunk to see if it can be applied that way.
-If it can, you will be asked if you want to have the
-.B \-R
-switch set.
-If it can't, the patch will continue to be applied normally.
-(Note: this method cannot detect a reversed patch if it is a normal diff
-and if the first command is an append (i.e. it should have been a delete)
-since appends always succeed, due to the fact that a null context will match
-anywhere.
-Luckily, most patches add or change lines rather than delete them, so most
-reversed normal diffs will begin with a delete, which will fail, triggering
-the heuristic.)
-.TP 5
-.B \-s
-makes
-.I patch
-do its work silently, unless an error occurs.
-.TP 5
-.B \-S
-causes
-.I patch
-to ignore this patch from the patch file, but continue on looking
-for the next patch in the file.
-Thus
-.sp
-	patch -S + -S + <patchfile
-.sp
-will ignore the first and second of three patches.
-.TP 5
-.B \-v
-causes
-.I patch
-to print out it's revision header and patch level.
-.TP 5
-.B \-x<number>
-sets internal debugging flags, and is of interest only to
-.I patch
-patchers.
-.SH ENVIRONMENT
-No environment variables are used by
-.IR patch .
-.SH FILES
-/tmp/patch*
-.SH SEE ALSO
-diff(1)
-.SH NOTES FOR PATCH SENDERS
+.Fl z
+options.
+The extension used for making backup files may also be specified in the
+.Ev SIMPLE_BACKUP_SUFFIX
+environment variable, which is overridden by the options above.
+.Pp
+If the backup file is a symbolic or hard link to the original file,
+.Nm
+creates a new backup file name by changing the first lowercase letter
+in the last component of the file's name into uppercase.
+If there are no more lowercase letters in the name,
+it removes the first character from the name.
+It repeats this process until it comes up with a
+backup file that does not already exist or is not linked to the original file.
+.Pp
+You may also specify where you want the output to go with the
+.Fl o
+option; if that file already exists, it is backed up first.
+.Ss Notes For Patch Senders
 There are several things you should bear in mind if you are going to
-be sending out patches.
-First, you can save people a lot of grief by keeping a patchlevel.h file
-which is patched to increment the patch level as the first diff in the
+be sending out patches:
+.Pp
+First, you can save people a lot of grief by keeping a
+.Pa patchlevel.h
+file which is patched to increment the patch level as the first diff in the
 patch file you send out.
-If you put a Prereq: line in with the patch, it won't let them apply
+If you put a
+.Qq Prereq:
+line in with the patch, it won't let them apply
 patches out of order without some warning.
-Second, make sure you've specified the filenames right, either in a
-context diff header, or with an Index: line.
+.Pp
+Second, make sure you've specified the file names right, either in a
+context diff header, or with an
+.Qq Index:
+line.
 If you are patching something in a subdirectory, be sure to tell the patch
-user to specify a 
-.B \-p
-switch as needed.
+user to specify a
+.Fl p
+option as needed.
+.Pp
 Third, you can create a file by sending out a diff that compares a
 null file to the file you want to create.
 This will only work if the file you want to create doesn't exist already in
 the target directory.
+.Pp
 Fourth, take care not to send out reversed patches, since it makes people wonder
 whether they already applied the patch.
+.Pp
 Fifth, while you may be able to get away with putting 582 diff listings into
 one file, it is probably wiser to group related patches into separate files in
 case something goes haywire.
-.SH DIAGNOSTICS
+.Sh ENVIRONMENT
+.Bl -tag -width "PATCH_VERSION_CONTROL" -compact
+.It Ev POSIXLY_CORRECT
+When set,
+.Nm
+behaves as if the
+.Fl Fl posix
+option has been specified.
+.It Ev SIMPLE_BACKUP_SUFFIX
+Extension to use for backup file names instead of
+.Qq .orig .
+.It Ev TMPDIR
+Directory to put temporary files in; default is
+.Pa /tmp .
+.It Ev PATCH_VERSION_CONTROL
+Selects when numbered backup files are made.
+.It Ev VERSION_CONTROL
+Same as
+.Ev PATCH_VERSION_CONTROL .
+.El
+.Sh FILES
+.Bl -tag -width "$TMPDIR/patch*" -compact
+.It Pa $TMPDIR/patch*
+.Nm
+temporary files
+.It Pa /dev/tty
+used to read input when
+.Nm
+prompts the user
+.El
+.Sh DIAGNOSTICS
 Too many to list here, but generally indicative that
-.I patch
+.Nm
 couldn't parse your patch file.
-.PP
-The message \*(L"Hmm...\*(R" indicates that there is unprocessed text in
-the patch file and that
-.I patch
+.Pp
+The message
+.Qq Hmm...
+indicates that there is unprocessed text in the patch file and that
+.Nm
 is attempting to intuit whether there is a patch in that text and, if so,
 what kind of patch it is.
-.SH CAVEATS
-.I Patch
+.Pp
+The
+.Nm
+utility exits with one of the following values:
+.Pp
+.Bl -tag -width Ds -compact -offset indent
+.It \&0
+Successful completion.
+.It \&1
+One or more lines were written to a reject file.
+.It \*[Gt]\&1
+An error occurred.
+.El
+.Pp
+When applying a set of patches in a loop it behooves you to check this
+exit status so you don't apply a later patch to a partially patched file.
+.Sh SEE ALSO
+.Xr diff 1
+.Sh AUTHORS
+.An Larry Wall
+with many other contributors.
+.Sh CAVEATS
+.Nm
 cannot tell if the line numbers are off in an ed script, and can only detect
-bad line numbers in a normal diff when it finds a \*(L"change\*(R" or
-a \*(L"delete\*(R" command.
+bad line numbers in a normal diff when it finds a
+.Qq change
+or a
+.Qq delete
+command.
 A context diff using fuzz factor 3 may have the same problem.
 Until a suitable interactive interface is added, you should probably do
 a context diff in these cases to see if the changes made sense.
 Of course, compiling without errors is a pretty good indication that the patch
 worked, but not always.
-.PP
-.I Patch
+.Pp
+.Nm
 usually produces the correct results, even when it has to do a lot of
 guessing.
 However, the results are guaranteed to be correct only when the patch is
 applied to exactly the same version of the file that the patch was
 generated from.
-.SH BUGS
-Could be smarter about partial matches, excessively \&deviant offsets and
+.Sh BUGS
+Could be smarter about partial matches, excessively deviant offsets and
 swapped code, but that would take an extra pass.
-.PP
+.Pp
+Check patch mode
+.Pq Fl C
+will fail if you try to check several patches in succession that build on
+each other.
+The entire
+.Nm
+code would have to be restructured to keep temporary files around so that it
+can handle this situation.
+.Pp
 If code has been duplicated (for instance with #ifdef OLDCODE ... #else ...
 #endif),
-.I patch
+.Nm
 is incapable of patching both versions, and, if it works at all, will likely
 patch the wrong one, and tell you that it succeeded to boot.
-.PP
+.Pp
 If you apply a patch you've already applied,
-.I patch
+.Nm
 will think it is a reversed patch, and offer to un-apply the patch.
 This could be construed as a feature.
diff --git a/usr.bin/patch/patch.c b/usr.bin/patch/patch.c
index 0f91c5c..7b75487 100644
--- a/usr.bin/patch/patch.c
+++ b/usr.bin/patch/patch.c
@@ -1,800 +1,974 @@
-#ifndef lint
-static char sccsid[] = "@(#)patch.c	8.1 (Berkeley) 6/6/93";
-#endif not lint
-
-char rcsid[] =
-	"$Header: patch.c,v 2.0.1.4 87/02/16 14:00:04 lwall Exp $";
+/*	$OpenBSD: patch.c,v 1.41 2004/07/09 19:13:46 otto Exp $	*/
 
-/* patch - a program to apply diffs to original files
- *
- * Copyright 1986, Larry Wall
- *
- * This program may be copied as long as you don't try to make any
- * money off of it, or pretend that you wrote it.
- *
- * $Log:	patch.c,v $
- * Revision 2.0.1.4  87/02/16  14:00:04  lwall
- * Short replacement caused spurious "Out of sync" message.
- * 
- * Revision 2.0.1.3  87/01/30  22:45:50  lwall
- * Improved diagnostic on sync error.
- * Moved do_ed_script() to pch.c.
- * 
- * Revision 2.0.1.2  86/11/21  09:39:15  lwall
- * Fuzz factor caused offset of installed lines.
- * 
- * Revision 2.0.1.1  86/10/29  13:10:22  lwall
- * Backwards search could terminate prematurely.
- * 
- * Revision 2.0  86/09/17  15:37:32  lwall
- * Baseline for netwide release.
- * 
- * Revision 1.5  86/08/01  20:53:24  lwall
- * Changed some %d's to %ld's.
- * Linted.
- * 
- * Revision 1.4  86/08/01  19:17:29  lwall
- * Fixes for machines that can't vararg.
- * Added fuzz factor.
- * Generalized -p.
- * General cleanup.
- * 
- * 85/08/15 van%ucbmonet@berkeley
- * Changes for 4.3bsd diff -c.
- *
- * Revision 1.3  85/03/26  15:07:43  lwall
- * Frozen.
- * 
- * Revision 1.2.1.9  85/03/12  17:03:35  lwall
- * Changed pfp->_file to fileno(pfp).
- * 
- * Revision 1.2.1.8  85/03/12  16:30:43  lwall
- * Check i_ptr and i_womp to make sure they aren't null before freeing.
- * Also allow ed output to be suppressed.
- * 
- * Revision 1.2.1.7  85/03/12  15:56:13  lwall
- * Added -p option from jromine@uci-750a.
- * 
- * Revision 1.2.1.6  85/03/12  12:12:51  lwall
- * Now checks for normalness of file to patch.
- * 
- * Revision 1.2.1.5  85/03/12  11:52:12  lwall
- * Added -D (#ifdef) option from joe@fluke.
+/*
+ * patch - a program to apply diffs to original files
  * 
- * Revision 1.2.1.4  84/12/06  11:14:15  lwall
- * Made smarter about SCCS subdirectories.
- * 
- * Revision 1.2.1.3  84/12/05  11:18:43  lwall
- * Added -l switch to do loose string comparison.
- * 
- * Revision 1.2.1.2  84/12/04  09:47:13  lwall
- * Failed hunk count not reset on multiple patch file.
- * 
- * Revision 1.2.1.1  84/12/04  09:42:37  lwall
- * Branch for sdcrdcf changes.
+ * Copyright 1986, Larry Wall
  * 
- * Revision 1.2  84/11/29  13:29:51  lwall
- * Linted.  Identifiers uniqified.  Fixed i_ptr malloc() bug.  Fixed
- * multiple calls to mktemp().  Will now work on machines that can only
- * read 32767 chars.  Added -R option for diffs with new and old swapped.
- * Various cosmetic changes.
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following condition is met:
+ * 1. Redistributions of source code must retain the above copyright notice,
+ * this condition and the following disclaimer.
  * 
- * Revision 1.1  84/11/09  17:03:58  lwall
- * Initial revision
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
  * 
+ * -C option added in 1998, original code by Marc Espie, based on FreeBSD
+ * behaviour
  */
 
-#include "INTERN.h"
+#ifndef lint
+static const char rcsid[] = "$OpenBSD: patch.c,v 1.41 2004/07/09 19:13:46 otto Exp $";
+#endif /* not lint */
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+
+#include <ctype.h>
+#include <getopt.h>
+#include <limits.h>
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+
 #include "common.h"
-#include "EXTERN.h"
-#include "version.h"
 #include "util.h"
 #include "pch.h"
 #include "inp.h"
+#include "backupfile.h"
+#include "pathnames.h"
+
+int		filemode = 0644;
+
+char		buf[MAXLINELEN];	/* general purpose buffer */
+
+bool		using_plan_a = true;	/* try to keep everything in memory */
+bool		out_of_mem = false;	/* ran out of memory in plan a */
+
+#define MAXFILEC 2
+
+char		*filearg[MAXFILEC];
+bool		ok_to_create_file = false;
+char		*outname = NULL;
+char		*origprae = NULL;
+char		*TMPOUTNAME;
+char		*TMPINNAME;
+char		*TMPREJNAME;
+char		*TMPPATNAME;
+bool		toutkeep = false;
+bool		trejkeep = false;
+bool		warn_on_invalid_line;
+bool		last_line_missing_eol;
+
+#ifdef DEBUGGING
+int		debug = 0;
+#endif
+
+bool		force = false;
+bool		batch = false;
+bool		verbose = true;
+bool		reverse = false;
+bool		noreverse = false;
+bool		skip_rest_of_patch = false;
+int		strippath = 957;
+bool		canonicalize = false;
+bool		check_only = false;
+int		diff_type = 0;
+char		*revision = NULL;	/* prerequisite revision, if any */
+LINENUM		input_lines = 0;	/* how long is input file in lines */
+int		posix = 0;		/* strict POSIX mode? */
+
+static void	reinitialize_almost_everything(void);
+static void	get_some_switches(void);
+static LINENUM	locate_hunk(LINENUM);
+static void	abort_hunk(void);
+static void	apply_hunk(LINENUM);
+static void	init_output(const char *);
+static void	init_reject(const char *);
+static void	copy_till(LINENUM, bool);
+static void	spew_output(void);
+static void	dump_line(LINENUM, bool);
+static bool	patch_match(LINENUM, LINENUM, LINENUM);
+static bool	similar(const char *, const char *, int);
+static __dead void usage(void);
+
+/* true if -E was specified on command line.  */
+static bool	remove_empty_files = false;
+
+/* true if -R was specified on command line.  */
+static bool	reverse_flag_specified = false;
+
+/* buffer holding the name of the rejected patch file. */
+static char	rejname[NAME_MAX + 1];
+
+/* buffer for stderr */
+static char	serrbuf[BUFSIZ];
+
+/* how many input lines have been irretractibly output */
+static LINENUM	last_frozen_line = 0;
+
+static int	Argc;		/* guess */
+static char	**Argv;
+static int	Argc_last;	/* for restarting plan_b */
+static char	**Argv_last;
+
+static FILE	*ofp = NULL;	/* output file pointer */
+static FILE	*rejfp = NULL;	/* reject file pointer */
+
+static int	filec = 0;	/* how many file arguments? */
+static LINENUM	last_offset = 0;
+static LINENUM	maxfuzz = 2;
+
+/* patch using ifdef, ifndef, etc. */
+static bool		do_defines = false;
+/* #ifdef xyzzy */
+static char		if_defined[128];
+/* #ifndef xyzzy */
+static char		not_defined[128];
+/* #else */
+static const char	else_defined[] = "#else\n";
+/* #endif xyzzy */
+static char		end_defined[128];
 
-/* procedures */
-
-void reinitialize_almost_everything();
-void get_some_switches();
-LINENUM locate_hunk();
-void abort_hunk();
-void apply_hunk();
-void init_output();
-void init_reject();
-void copy_till();
-void spew_output();
-void dump_line();
-bool patch_match();
-bool similar();
-void re_input();
-void my_exit();
 
 /* Apply a set of diffs as appropriate. */
 
-main(argc,argv)
-int argc;
-char **argv;
+int
+main(int argc, char *argv[])
 {
-    LINENUM where;
-    LINENUM newwhere;
-    LINENUM fuzz;
-    LINENUM mymaxfuzz;
-    int hunk = 0;
-    int failed = 0;
-    int i;
-
-    setbuf(stderr, serrbuf);
-    for (i = 0; i<MAXFILEC; i++)
-	filearg[i] = Nullch;
-    Mktemp(TMPOUTNAME);
-    Mktemp(TMPINNAME);
-    Mktemp(TMPREJNAME);
-    Mktemp(TMPPATNAME);
-
-    /* parse switches */
-    Argc = argc;
-    Argv = argv;
-    get_some_switches();
-    
-    /* make sure we clean up /tmp in case of disaster */
-    set_signals();
-
-    for (
-	open_patch_file(filearg[1]);
-	there_is_another_patch();
-	reinitialize_almost_everything()
-    ) {					/* for each patch in patch file */
-
-	if (outname == Nullch)
-	    outname = savestr(filearg[0]);
-    
-	/* initialize the patched file */
-	if (!skip_rest_of_patch)
-	    init_output(TMPOUTNAME);
-    
-	/* for ed script just up and do it and exit */
-	if (diff_type == ED_DIFF) {
-	    do_ed_script();
-	    continue;
+	int	error = 0, hunk, failed, patch_seen = 0, i, fd;
+	LINENUM	where = 0, newwhere, fuzz, mymaxfuzz;
+	const	char *tmpdir;
+	char	*v;
+
+	setbuf(stderr, serrbuf);
+	for (i = 0; i < MAXFILEC; i++)
+		filearg[i] = NULL;
+
+	/* Cons up the names of the temporary files.  */
+	if ((tmpdir = getenv("TMPDIR")) == NULL || *tmpdir == '\0')
+		tmpdir = _PATH_TMP;
+	for (i = strlen(tmpdir) - 1; i > 0 && tmpdir[i] == '/'; i--)
+		;
+	i++;
+	if (asprintf(&TMPOUTNAME, "%.*s/patchoXXXXXXXXXX", i, tmpdir) == -1)
+		fatal("cannot allocate memory");
+	if ((fd = mkstemp(TMPOUTNAME)) < 0)
+		pfatal("can't create %s", TMPOUTNAME);
+	close(fd);
+
+	if (asprintf(&TMPINNAME, "%.*s/patchiXXXXXXXXXX", i, tmpdir) == -1)
+		fatal("cannot allocate memory");
+	if ((fd = mkstemp(TMPINNAME)) < 0)
+		pfatal("can't create %s", TMPINNAME);
+	close(fd);
+
+	if (asprintf(&TMPREJNAME, "%.*s/patchrXXXXXXXXXX", i, tmpdir) == -1)
+		fatal("cannot allocate memory");
+	if ((fd = mkstemp(TMPREJNAME)) < 0)
+		pfatal("can't create %s", TMPREJNAME);
+	close(fd);
+
+	if (asprintf(&TMPPATNAME, "%.*s/patchpXXXXXXXXXX", i, tmpdir) == -1)
+		fatal("cannot allocate memory");
+	if ((fd = mkstemp(TMPPATNAME)) < 0)
+		pfatal("can't create %s", TMPPATNAME);
+	close(fd);
+
+	v = getenv("SIMPLE_BACKUP_SUFFIX");
+	if (v)
+		simple_backup_suffix = v;
+	else
+		simple_backup_suffix = ORIGEXT;
+
+	/* parse switches */
+	Argc = argc;
+	Argv = argv;
+	get_some_switches();
+
+	if (backup_type == none) {
+		if ((v = getenv("PATCH_VERSION_CONTROL")) == NULL)
+			v = getenv("VERSION_CONTROL");
+		if (v != NULL || !posix)
+			backup_type = get_version(v);	/* OK to pass NULL. */
 	}
-    
-	/* initialize reject file */
-	init_reject(TMPREJNAME);
-    
-	/* find out where all the lines are */
-	if (!skip_rest_of_patch)
-	    scan_input(filearg[0]);
-    
-	/* from here on, open no standard i/o files, because malloc */
-	/* might misfire and we can't catch it easily */
-    
-	/* apply each hunk of patch */
-	hunk = 0;
-	failed = 0;
-	out_of_mem = FALSE;
-	while (another_hunk()) {
-	    hunk++;
-	    fuzz = Nulline;
-	    mymaxfuzz = pch_context();
-	    if (maxfuzz < mymaxfuzz)
-		mymaxfuzz = maxfuzz;
-	    if (!skip_rest_of_patch) {
-		do {
-		    where = locate_hunk(fuzz);
-		    if (hunk == 1 && where == Nulline && !force) {
+
+	/* make sure we clean up /tmp in case of disaster */
+	set_signals(0);
+
+	for (open_patch_file(filearg[1]); there_is_another_patch();
+	    reinitialize_almost_everything()) {
+		/* for each patch in patch file */
+
+		patch_seen = true;
+		warn_on_invalid_line = true;
+
+		if (outname == NULL)
+			outname = savestr(filearg[0]);
+
+		/* for ed script just up and do it and exit */
+		if (diff_type == ED_DIFF) {
+			do_ed_script();
+			continue;
+		}
+		/* initialize the patched file */
+		if (!skip_rest_of_patch)
+			init_output(TMPOUTNAME);
+
+		/* initialize reject file */
+		init_reject(TMPREJNAME);
+
+		/* find out where all the lines are */
+		if (!skip_rest_of_patch)
+			scan_input(filearg[0]);
+
+		/* from here on, open no standard i/o files, because malloc */
+		/* might misfire and we can't catch it easily */
+
+		/* apply each hunk of patch */
+		hunk = 0;
+		failed = 0;
+		out_of_mem = false;
+		while (another_hunk()) {
+			hunk++;
+			fuzz = 0;
+			mymaxfuzz = pch_context();
+			if (maxfuzz < mymaxfuzz)
+				mymaxfuzz = maxfuzz;
+			if (!skip_rest_of_patch) {
+				do {
+					where = locate_hunk(fuzz);
+					if (hunk == 1 && where == 0 && !force) {
 						/* dwim for reversed patch? */
-			if (!pch_swap()) {
-			    if (fuzz == Nulline)
-				say1("\
-Not enough memory to try swapped hunk!  Assuming unswapped.\n");
-			    continue;
-			}
-			reverse = !reverse;
-			where = locate_hunk(fuzz);  /* try again */
-			if (where == Nulline) {	    /* didn't find it swapped */
-			    if (!pch_swap())         /* put it back to normal */
-				fatal1("Lost hunk on alloc error!\n");
-			    reverse = !reverse;
+						if (!pch_swap()) {
+							if (fuzz == 0)
+								say("Not enough memory to try swapped hunk!  Assuming unswapped.\n");
+							continue;
+						}
+						reverse = !reverse;
+						/* try again */
+						where = locate_hunk(fuzz);
+						if (where == 0) {
+							/* didn't find it swapped */
+							if (!pch_swap())
+								/* put it back to normal */
+								fatal("lost hunk on alloc error!\n");
+							reverse = !reverse;
+						} else if (noreverse) {
+							if (!pch_swap())
+								/* put it back to normal */
+								fatal("lost hunk on alloc error!\n");
+							reverse = !reverse;
+							say("Ignoring previously applied (or reversed) patch.\n");
+							skip_rest_of_patch = true;
+						} else if (batch) {
+							if (verbose)
+								say("%seversed (or previously applied) patch detected!  %s -R.",
+								    reverse ? "R" : "Unr",
+								    reverse ? "Assuming" : "Ignoring");
+						} else {
+							ask("%seversed (or previously applied) patch detected!  %s -R? [y] ",
+							    reverse ? "R" : "Unr",
+							    reverse ? "Assume" : "Ignore");
+							if (*buf == 'n') {
+								ask("Apply anyway? [n] ");
+								if (*buf != 'y')
+									skip_rest_of_patch = true;
+								where = 0;
+								reverse = !reverse;
+								if (!pch_swap())
+									/* put it back to normal */
+									fatal("lost hunk on alloc error!\n");
+							}
+						}
+					}
+				} while (!skip_rest_of_patch && where == 0 &&
+				    ++fuzz <= mymaxfuzz);
+
+				if (skip_rest_of_patch) {	/* just got decided */
+					fclose(ofp);
+					ofp = NULL;
+				}
 			}
-			else if (noreverse) {
-			    if (!pch_swap())         /* put it back to normal */
-				fatal1("Lost hunk on alloc error!\n");
-			    reverse = !reverse;
-			    say1("\
-Ignoring previously applied (or reversed) patch.\n");
-			    skip_rest_of_patch = TRUE;
+			newwhere = pch_newfirst() + last_offset;
+			if (skip_rest_of_patch) {
+				abort_hunk();
+				failed++;
+				if (verbose)
+					say("Hunk #%d ignored at %ld.\n",
+					    hunk, newwhere);
+			} else if (where == 0) {
+				abort_hunk();
+				failed++;
+				if (verbose)
+					say("Hunk #%d failed at %ld.\n",
+					    hunk, newwhere);
+			} else {
+				apply_hunk(where);
+				if (verbose) {
+					say("Hunk #%d succeeded at %ld",
+					    hunk, newwhere);
+					if (fuzz != 0)
+						say(" with fuzz %ld", fuzz);
+					if (last_offset)
+						say(" (offset %ld line%s)",
+						    last_offset,
+						    last_offset == 1L ? "" : "s");
+					say(".\n");
+				}
 			}
-			else {
-			    ask3("\
-%seversed (or previously applied) patch detected!  %s -R? [y] ",
-				reverse ? "R" : "Unr",
-				reverse ? "Assume" : "Ignore");
-			    if (*buf == 'n') {
-				ask1("Apply anyway? [n] ");
-				if (*buf != 'y')
-				    skip_rest_of_patch = TRUE;
-				where = Nulline;
-				reverse = !reverse;
-				if (!pch_swap())  /* put it back to normal */
-				    fatal1("Lost hunk on alloc error!\n");
-			    }
-			}
-		    }
-		} while (!skip_rest_of_patch && where == Nulline &&
-		    ++fuzz <= mymaxfuzz);
+		}
 
-		if (skip_rest_of_patch) {		/* just got decided */
-		    Fclose(ofp);
-		    ofp = Nullfp;
+		if (out_of_mem && using_plan_a) {
+			Argc = Argc_last;
+			Argv = Argv_last;
+			say("\n\nRan out of memory using Plan A--trying again...\n\n");
+			if (ofp)
+				fclose(ofp);
+			ofp = NULL;
+			if (rejfp)
+				fclose(rejfp);
+			rejfp = NULL;
+			continue;
+		}
+		if (hunk == 0)
+			fatal("Internal error: hunk should not be 0\n");
+
+		/* finish spewing out the new file */
+		if (!skip_rest_of_patch)
+			spew_output();
+
+		/* and put the output where desired */
+		ignore_signals();
+		if (!skip_rest_of_patch) {
+			struct stat	statbuf;
+			char	*realout = outname;
+
+			if (!check_only) {
+				if (move_file(TMPOUTNAME, outname) < 0) {
+					toutkeep = true;
+					realout = TMPOUTNAME;
+					chmod(TMPOUTNAME, filemode);
+				} else
+					chmod(outname, filemode);
+
+				if (remove_empty_files &&
+				    stat(realout, &statbuf) == 0 &&
+				    statbuf.st_size == 0) {
+					if (verbose)
+						say("Removing %s (empty after patching).\n",
+						    realout);
+					unlink(realout);
+				}
+			}
 		}
-	    }
-
-	    newwhere = pch_newfirst() + last_offset;
-	    if (skip_rest_of_patch) {
-		abort_hunk();
-		failed++;
-		if (verbose)
-		    say3("Hunk #%d ignored at %ld.\n", hunk, newwhere);
-	    }
-	    else if (where == Nulline) {
-		abort_hunk();
-		failed++;
-		if (verbose)
-		    say3("Hunk #%d failed at %ld.\n", hunk, newwhere);
-	    }
-	    else {
-		apply_hunk(where);
-		if (verbose) {
-		    say3("Hunk #%d succeeded at %ld", hunk, newwhere);
-		    if (fuzz)
-			say2(" with fuzz %ld", fuzz);
-		    if (last_offset)
-			say3(" (offset %ld line%s)",
-			    last_offset, last_offset==1L?"":"s");
-		    say1(".\n");
+		fclose(rejfp);
+		rejfp = NULL;
+		if (failed) {
+			error = 1;
+			if (*rejname == '\0') {
+				if (strlcpy(rejname, outname,
+				    sizeof(rejname)) >= sizeof(rejname))
+					fatal("filename %s is too long\n", outname);
+				if (strlcat(rejname, REJEXT,
+				    sizeof(rejname)) >= sizeof(rejname))
+					fatal("filename %s is too long\n", outname);
+			}
+			if (skip_rest_of_patch) {
+				say("%d out of %d hunks ignored--saving rejects to %s\n",
+				    failed, hunk, rejname);
+			} else {
+				say("%d out of %d hunks failed--saving rejects to %s\n",
+				    failed, hunk, rejname);
+			}
+			if (!check_only && move_file(TMPREJNAME, rejname) < 0)
+				trejkeep = true;
 		}
-	    }
-	}
-
-	if (out_of_mem && using_plan_a) {
-	    Argc = Argc_last;
-	    Argv = Argv_last;
-	    say1("\n\nRan out of memory using Plan A--trying again...\n\n");
-	    continue;
-	}
-    
-	assert(hunk);
-    
-	/* finish spewing out the new file */
-	if (!skip_rest_of_patch)
-	    spew_output();
-	
-	/* and put the output where desired */
-	ignore_signals();
-	if (!skip_rest_of_patch) {
-	    if (move_file(TMPOUTNAME, outname) < 0) {
-		toutkeep = TRUE;
-		chmod(TMPOUTNAME, filemode);
-	    }
-	    else
-		chmod(outname, filemode);
-	}
-	Fclose(rejfp);
-	rejfp = Nullfp;
-	if (failed) {
-	    if (!*rejname) {
-		Strcpy(rejname, outname);
-		Strcat(rejname, ".rej");
-	    }
-	    if (skip_rest_of_patch) {
-		say4("%d out of %d hunks ignored--saving rejects to %s\n",
-		    failed, hunk, rejname);
-	    }
-	    else {
-		say4("%d out of %d hunks failed--saving rejects to %s\n",
-		    failed, hunk, rejname);
-	    }
-	    if (move_file(TMPREJNAME, rejname) < 0)
-		trejkeep = TRUE;
+		set_signals(1);
 	}
-	set_signals();
-    }
-    my_exit(0);
+	my_exit(error);
+	/* NOTREACHED */
 }
 
 /* Prepare to find the next patch to do in the patch file. */
 
-void
-reinitialize_almost_everything()
+static void
+reinitialize_almost_everything(void)
 {
-    re_patch();
-    re_input();
+	re_patch();
+	re_input();
 
-    input_lines = 0;
-    last_frozen_line = 0;
+	input_lines = 0;
+	last_frozen_line = 0;
 
-    filec = 0;
-    if (filearg[0] != Nullch && !out_of_mem) {
-	free(filearg[0]);
-	filearg[0] = Nullch;
-    }
+	filec = 0;
+	if (!out_of_mem) {
+		free(filearg[0]);
+		filearg[0] = NULL;
+	}
 
-    if (outname != Nullch) {
 	free(outname);
-	outname = Nullch;
-    }
-
-    last_offset = 0;
+	outname = NULL;
 
-    diff_type = 0;
+	last_offset = 0;
+	diff_type = 0;
 
-    if (revision != Nullch) {
 	free(revision);
-	revision = Nullch;
-    }
+	revision = NULL;
 
-    reverse = FALSE;
-    skip_rest_of_patch = FALSE;
+	reverse = reverse_flag_specified;
+	skip_rest_of_patch = false;
 
-    get_some_switches();
-
-    if (filec >= 2)
-	fatal1("You may not change to a different patch file.\n");
+	get_some_switches();
 }
 
-/* Process switches and filenames up to next '+' or end of list. */
+/* Process switches and filenames. */
 
-void
-get_some_switches()
+static void
+get_some_switches(void)
 {
-    Reg1 char *s;
-
-    rejname[0] = '\0';
-    Argc_last = Argc;
-    Argv_last = Argv;
-    if (!Argc)
-	return;
-    for (Argc--,Argv++; Argc; Argc--,Argv++) {
-	s = Argv[0];
-	if (strEQ(s, "+")) {
-	    return;			/* + will be skipped by for loop */
-	}
-	if (*s != '-' || !s[1]) {
-	    if (filec == MAXFILEC)
-		fatal1("Too many file arguments.\n");
-	    filearg[filec++] = savestr(s);
-	}
-	else {
-	    switch (*++s) {
-	    case 'b':
-		origext = savestr(Argv[1]);
-		Argc--,Argv++;
-		break;
-	    case 'c':
-		diff_type = CONTEXT_DIFF;
-		break;
-	    case 'd':
-		if (!*++s) {
-		    Argc--,Argv++;
-		    s = Argv[0];
-		}
-		if (chdir(s) < 0)
-		    fatal2("Can't cd to %s.\n", s);
-		break;
-	    case 'D':
-	    	do_defines = TRUE;
-		if (!*++s) {
-		    Argc--,Argv++;
-		    s = Argv[0];
-		}
-		Sprintf(if_defined, "#ifdef %s\n", s);
-		Sprintf(not_defined, "#ifndef %s\n", s);
-		Sprintf(end_defined, "#endif /* %s */\n", s);
-		break;
-	    case 'e':
-		diff_type = ED_DIFF;
-		break;
-	    case 'f':
-		force = TRUE;
-		break;
-	    case 'F':
-		if (*++s == '=')
-		    s++;
-		maxfuzz = atoi(s);
-		break;
-	    case 'l':
-		canonicalize = TRUE;
-		break;
-	    case 'n':
-		diff_type = NORMAL_DIFF;
-		break;
-	    case 'N':
-		noreverse = TRUE;
-		break;
-	    case 'o':
-		outname = savestr(Argv[1]);
-		Argc--,Argv++;
-		break;
-	    case 'p':
-		if (*++s == '=')
-		    s++;
-		strippath = atoi(s);
-		break;
-	    case 'r':
-		Strcpy(rejname, Argv[1]);
-		Argc--,Argv++;
-		break;
-	    case 'R':
-		reverse = TRUE;
-		break;
-	    case 's':
-		verbose = FALSE;
-		break;
-	    case 'S':
-		skip_rest_of_patch = TRUE;
-		break;
-	    case 'v':
-		version();
-		break;
+	const char *options = "b::B:cCd:D:eEfF:i:lnNo:p:r:RstuvV:x:z:";
+	static struct option longopts[] = {
+		{"backup",		no_argument,		0,	'b'},
+		{"batch",		no_argument,		0,	't'},
+		{"check",		no_argument,		0,	'C'},
+		{"context",		no_argument,		0,	'c'},
+		{"debug",		required_argument,	0,	'x'},
+		{"directory",		required_argument,	0,	'd'},
+		{"ed",			no_argument,		0,	'e'},
+		{"force",		no_argument,		0,	'f'},
+		{"forward",		no_argument,		0,	'N'},
+		{"fuzz",		required_argument,	0,	'F'},
+		{"ifdef",		required_argument,	0,	'D'},
+		{"input",		required_argument,	0,	'i'},
+		{"ignore-whitespace",	no_argument,		0,	'l'},
+		{"normal",		no_argument,		0,	'n'},
+		{"output",		required_argument,	0,	'o'},
+		{"prefix",		required_argument,	0,	'B'},
+		{"quiet",		no_argument,		0,	's'},
+		{"reject-file",		required_argument,	0,	'r'},
+		{"remove-empty-files",	no_argument,		0,	'E'},
+		{"reverse",		no_argument,		0,	'R'},
+		{"silent",		no_argument,		0,	's'},
+		{"strip",		required_argument,	0,	'p'},
+		{"suffix",		required_argument,	0,	'z'},
+		{"unified",		no_argument,		0,	'u'},
+		{"version",		no_argument,		0,	'v'},
+		{"version-control",	required_argument,	0,	'V'},
+		{"posix",		no_argument,		&posix,	1},
+		{NULL,			0,			0,	0}
+	};
+	int ch;
+
+	rejname[0] = '\0';
+	Argc_last = Argc;
+	Argv_last = Argv;
+	if (!Argc)
+		return;
+	optreset = optind = 1;
+	while ((ch = getopt_long(Argc, Argv, options, longopts, NULL)) != -1) {
+		switch (ch) {
+		case 'b':
+			if (backup_type == none)
+				backup_type = numbered_existing;
+			if (optarg == NULL)
+				break;
+			if (verbose)
+				say("Warning, the ``-b suffix'' option has been"
+				    " obsoleted by the -z option.\n");
+			/* FALLTHROUGH */
+		case 'z':
+			/* must directly follow 'b' case for backwards compat */
+			simple_backup_suffix = savestr(optarg);
+			break;
+		case 'B':
+			origprae = savestr(optarg);
+			break;
+		case 'c':
+			diff_type = CONTEXT_DIFF;
+			break;
+		case 'C':
+			check_only = true;
+			break;
+		case 'd':
+			if (chdir(optarg) < 0)
+				pfatal("can't cd to %s", optarg);
+			break;
+		case 'D':
+			do_defines = true;
+			if (!isalpha(*optarg) && *optarg != '_')
+				fatal("argument to -D is not an identifier\n");
+			snprintf(if_defined, sizeof if_defined,
+			    "#ifdef %s\n", optarg);
+			snprintf(not_defined, sizeof not_defined,
+			    "#ifndef %s\n", optarg);
+			snprintf(end_defined, sizeof end_defined,
+			    "#endif /* %s */\n", optarg);
+			break;
+		case 'e':
+			diff_type = ED_DIFF;
+			break;
+		case 'E':
+			remove_empty_files = true;
+			break;
+		case 'f':
+			force = true;
+			break;
+		case 'F':
+			maxfuzz = atoi(optarg);
+			break;
+		case 'i':
+			if (++filec == MAXFILEC)
+				fatal("too many file arguments\n");
+			filearg[filec] = savestr(optarg);
+			break;
+		case 'l':
+			canonicalize = true;
+			break;
+		case 'n':
+			diff_type = NORMAL_DIFF;
+			break;
+		case 'N':
+			noreverse = true;
+			break;
+		case 'o':
+			outname = savestr(optarg);
+			break;
+		case 'p':
+			strippath = atoi(optarg);
+			break;
+		case 'r':
+			if (strlcpy(rejname, optarg,
+			    sizeof(rejname)) >= sizeof(rejname))
+				fatal("argument for -r is too long\n");
+			break;
+		case 'R':
+			reverse = true;
+			reverse_flag_specified = true;
+			break;
+		case 's':
+			verbose = false;
+			break;
+		case 't':
+			batch = true;
+			break;
+		case 'u':
+			diff_type = UNI_DIFF;
+			break;
+		case 'v':
+			version();
+			break;
+		case 'V':
+			backup_type = get_version(optarg);
+			break;
 #ifdef DEBUGGING
-	    case 'x':
-		debug = atoi(s+1);
-		break;
+		case 'x':
+			debug = atoi(optarg);
+			break;
 #endif
-	    default:
-		fatal2("Unrecognized switch: %s\n", Argv[0]);
-	    }
+		default:
+			if (ch != '\0')
+				usage();
+			break;
+		}
+	}
+	Argc -= optind;
+	Argv += optind;
+
+	if (Argc > 0) {
+		filearg[0] = savestr(*Argv++);
+		Argc--;
+		while (Argc > 0) {
+			if (++filec == MAXFILEC)
+				fatal("too many file arguments\n");
+			filearg[filec] = savestr(*Argv++);
+			Argc--;
+		}
 	}
-    }
+
+	if (getenv("POSIXLY_CORRECT") != NULL)
+		posix = 1;
 }
 
-/* Attempt to find the right place to apply this hunk of patch. */
+static __dead void
+usage(void)
+{
+	fprintf(stderr,
+"usage: patch [-bcCeEflnNRstuv] [-B backup-prefix] [-d directory] [-D symbol]\n"
+"             [-F max-fuzz] [-i patchfile] [-o out-file] [-p strip-count]\n"
+"             [-r rej-name] [-V {numbered,existing,simple}] [-z backup-ext]\n"
+"             [origfile [patchfile]]\n");
+	my_exit(EXIT_SUCCESS);
+}
 
-LINENUM
-locate_hunk(fuzz)
-LINENUM fuzz;
+/*
+ * Attempt to find the right place to apply this hunk of patch.
+ */
+static LINENUM
+locate_hunk(LINENUM fuzz)
 {
-    Reg1 LINENUM first_guess = pch_first() + last_offset;
-    Reg2 LINENUM offset;
-    LINENUM pat_lines = pch_ptrn_lines();
-    Reg3 LINENUM max_pos_offset = input_lines - first_guess
-				- pat_lines + 1; 
-    Reg4 LINENUM max_neg_offset = first_guess - last_frozen_line - 1
-				+ pch_context();
-
-    if (!pat_lines)			/* null range matches always */
-	return first_guess;
-    if (max_neg_offset >= first_guess)	/* do not try lines < 0 */
-	max_neg_offset = first_guess - 1;
-    if (first_guess <= input_lines && patch_match(first_guess, Nulline, fuzz))
-	return first_guess;
-    for (offset = 1; ; offset++) {
-	Reg5 bool check_after = (offset <= max_pos_offset);
-	Reg6 bool check_before = (offset <= max_neg_offset);
-
-	if (check_after && patch_match(first_guess, offset, fuzz)) {
+	LINENUM	first_guess = pch_first() + last_offset;
+	LINENUM	offset;
+	LINENUM	pat_lines = pch_ptrn_lines();
+	LINENUM	max_pos_offset = input_lines - first_guess - pat_lines + 1;
+	LINENUM	max_neg_offset = first_guess - last_frozen_line - 1 + pch_context();
+
+	if (pat_lines == 0) {		/* null range matches always */
+		if (verbose && fuzz == 0 && (diff_type == CONTEXT_DIFF
+		    || diff_type == NEW_CONTEXT_DIFF
+		    || diff_type == UNI_DIFF)) {
+			say("Empty context always matches.\n");
+		}
+		if (diff_type == CONTEXT_DIFF
+		    || diff_type == NEW_CONTEXT_DIFF
+		    || diff_type == UNI_DIFF) {
+			if (fuzz == 0)
+				return (input_lines == 0 ? first_guess : 0);
+		} else
+			return (first_guess);
+	}
+	if (max_neg_offset >= first_guess)	/* do not try lines < 0 */
+		max_neg_offset = first_guess - 1;
+	if (first_guess <= input_lines && patch_match(first_guess, 0, fuzz))
+		return first_guess;
+	for (offset = 1; ; offset++) {
+		bool	check_after = (offset <= max_pos_offset);
+		bool	check_before = (offset <= max_neg_offset);
+
+		if (check_after && patch_match(first_guess, offset, fuzz)) {
 #ifdef DEBUGGING
-	    if (debug & 1)
-		say3("Offset changing from %ld to %ld\n", last_offset, offset);
+			if (debug & 1)
+				say("Offset changing from %ld to %ld\n",
+				    last_offset, offset);
 #endif
-	    last_offset = offset;
-	    return first_guess+offset;
-	}
-	else if (check_before && patch_match(first_guess, -offset, fuzz)) {
+			last_offset = offset;
+			return first_guess + offset;
+		} else if (check_before && patch_match(first_guess, -offset, fuzz)) {
 #ifdef DEBUGGING
-	    if (debug & 1)
-		say3("Offset changing from %ld to %ld\n", last_offset, -offset);
+			if (debug & 1)
+				say("Offset changing from %ld to %ld\n",
+				    last_offset, -offset);
 #endif
-	    last_offset = -offset;
-	    return first_guess-offset;
+			last_offset = -offset;
+			return first_guess - offset;
+		} else if (!check_before && !check_after)
+			return 0;
 	}
-	else if (!check_before && !check_after)
-	    return Nulline;
-    }
 }
 
 /* We did not find the pattern, dump out the hunk so they can handle it. */
 
-void
-abort_hunk()
+static void
+abort_hunk(void)
 {
-    Reg1 LINENUM i;
-    Reg2 LINENUM pat_end = pch_end();
-    /* add in last_offset to guess the same as the previous successful hunk */
-    LINENUM oldfirst = pch_first() + last_offset;
-    LINENUM newfirst = pch_newfirst() + last_offset;
-    LINENUM oldlast = oldfirst + pch_ptrn_lines() - 1;
-    LINENUM newlast = newfirst + pch_repl_lines() - 1;
-    char *stars = (diff_type == NEW_CONTEXT_DIFF ? " ****" : "");
-    char *minuses = (diff_type == NEW_CONTEXT_DIFF ? " ----" : " -----");
-
-    fprintf(rejfp, "***************\n");
-    for (i=0; i<=pat_end; i++) {
-	switch (pch_char(i)) {
-	case '*':
-	    if (oldlast < oldfirst)
-		fprintf(rejfp, "*** 0%s\n", stars);
-	    else if (oldlast == oldfirst)
-		fprintf(rejfp, "*** %ld%s\n", oldfirst, stars);
-	    else
-		fprintf(rejfp, "*** %ld,%ld%s\n", oldfirst, oldlast, stars);
-	    break;
-	case '=':
-	    if (newlast < newfirst)
-		fprintf(rejfp, "--- 0%s\n", minuses);
-	    else if (newlast == newfirst)
-		fprintf(rejfp, "--- %ld%s\n", newfirst, minuses);
-	    else
-		fprintf(rejfp, "--- %ld,%ld%s\n", newfirst, newlast, minuses);
-	    break;
-	case '\n':
-	    fprintf(rejfp, "%s", pfetch(i));
-	    break;
-	case ' ': case '-': case '+': case '!':
-	    fprintf(rejfp, "%c %s", pch_char(i), pfetch(i));
-	    break;
-	default:
-	    say1("Fatal internal error in abort_hunk().\n"); 
-	    abort();
+	LINENUM	i;
+	const LINENUM	pat_end = pch_end();
+	/*
+	 * add in last_offset to guess the same as the previous successful
+	 * hunk
+	 */
+	const LINENUM	oldfirst = pch_first() + last_offset;
+	const LINENUM	newfirst = pch_newfirst() + last_offset;
+	const LINENUM	oldlast = oldfirst + pch_ptrn_lines() - 1;
+	const LINENUM	newlast = newfirst + pch_repl_lines() - 1;
+	const char	*stars = (diff_type >= NEW_CONTEXT_DIFF ? " ****" : "");
+	const char	*minuses = (diff_type >= NEW_CONTEXT_DIFF ? " ----" : " -----");
+
+	fprintf(rejfp, "***************\n");
+	for (i = 0; i <= pat_end; i++) {
+		switch (pch_char(i)) {
+		case '*':
+			if (oldlast < oldfirst)
+				fprintf(rejfp, "*** 0%s\n", stars);
+			else if (oldlast == oldfirst)
+				fprintf(rejfp, "*** %ld%s\n", oldfirst, stars);
+			else
+				fprintf(rejfp, "*** %ld,%ld%s\n", oldfirst,
+				    oldlast, stars);
+			break;
+		case '=':
+			if (newlast < newfirst)
+				fprintf(rejfp, "--- 0%s\n", minuses);
+			else if (newlast == newfirst)
+				fprintf(rejfp, "--- %ld%s\n", newfirst, minuses);
+			else
+				fprintf(rejfp, "--- %ld,%ld%s\n", newfirst,
+				    newlast, minuses);
+			break;
+		case '\n':
+			fprintf(rejfp, "%s", pfetch(i));
+			break;
+		case ' ':
+		case '-':
+		case '+':
+		case '!':
+			fprintf(rejfp, "%c %s", pch_char(i), pfetch(i));
+			break;
+		default:
+			fatal("fatal internal error in abort_hunk\n");
+		}
 	}
-    }
 }
 
 /* We found where to apply it (we hope), so do it. */
 
-void
-apply_hunk(where)
-LINENUM where;
+static void
+apply_hunk(LINENUM where)
 {
-    Reg1 LINENUM old = 1;
-    Reg2 LINENUM lastline = pch_ptrn_lines();
-    Reg3 LINENUM new = lastline+1;
+	LINENUM		old = 1;
+	const LINENUM	lastline = pch_ptrn_lines();
+	LINENUM		new = lastline + 1;
 #define OUTSIDE 0
 #define IN_IFNDEF 1
 #define IN_IFDEF 2
 #define IN_ELSE 3
-    Reg4 int def_state = OUTSIDE;
-    Reg5 bool R_do_defines = do_defines;
-    Reg6 LINENUM pat_end = pch_end();
-
-    where--;
-    while (pch_char(new) == '=' || pch_char(new) == '\n')
-	new++;
-    
-    while (old <= lastline) {
-	if (pch_char(old) == '-') {
-	    copy_till(where + old - 1);
-	    if (R_do_defines) {
-		if (def_state == OUTSIDE) {
-		    fputs(not_defined, ofp);
-		    def_state = IN_IFNDEF;
-		}
-		else if (def_state == IN_IFDEF) {
-		    fputs(else_defined, ofp);
-		    def_state = IN_ELSE;
-		}
-		fputs(pfetch(old), ofp);
-	    }
-	    last_frozen_line++;
-	    old++;
-	}
-	else if (new > pat_end)
-	    break;
-	else if (pch_char(new) == '+') {
-	    copy_till(where + old - 1);
-	    if (R_do_defines) {
-		if (def_state == IN_IFNDEF) {
-		    fputs(else_defined, ofp);
-		    def_state = IN_ELSE;
-		}
-		else if (def_state == OUTSIDE) {
-		    fputs(if_defined, ofp);
-		    def_state = IN_IFDEF;
-		}
-	    }
-	    fputs(pfetch(new), ofp);
-	    new++;
-	}
-	else {
-	    if (pch_char(new) != pch_char(old)) {
-		say3("Out-of-sync patch, lines %ld,%ld--mangled text or line numbers, maybe?\n",
-		    pch_hunk_beg() + old,
-		    pch_hunk_beg() + new);
+	int		def_state = OUTSIDE;
+	const LINENUM	pat_end = pch_end();
+
+	where--;
+	while (pch_char(new) == '=' || pch_char(new) == '\n')
+		new++;
+
+	while (old <= lastline) {
+		if (pch_char(old) == '-') {
+			copy_till(where + old - 1, false);
+			if (do_defines) {
+				if (def_state == OUTSIDE) {
+					fputs(not_defined, ofp);
+					def_state = IN_IFNDEF;
+				} else if (def_state == IN_IFDEF) {
+					fputs(else_defined, ofp);
+					def_state = IN_ELSE;
+				}
+				fputs(pfetch(old), ofp);
+			}
+			last_frozen_line++;
+			old++;
+		} else if (new > pat_end) {
+			break;
+		} else if (pch_char(new) == '+') {
+			copy_till(where + old - 1, false);
+			if (do_defines) {
+				if (def_state == IN_IFNDEF) {
+					fputs(else_defined, ofp);
+					def_state = IN_ELSE;
+				} else if (def_state == OUTSIDE) {
+					fputs(if_defined, ofp);
+					def_state = IN_IFDEF;
+				}
+			}
+			fputs(pfetch(new), ofp);
+			new++;
+		} else if (pch_char(new) != pch_char(old)) {
+			say("Out-of-sync patch, lines %ld,%ld--mangled text or line numbers, maybe?\n",
+			    pch_hunk_beg() + old,
+			    pch_hunk_beg() + new);
 #ifdef DEBUGGING
-		say3("oldchar = '%c', newchar = '%c'\n",
-		    pch_char(old), pch_char(new));
+			say("oldchar = '%c', newchar = '%c'\n",
+			    pch_char(old), pch_char(new));
 #endif
-		my_exit(1);
-	    }
-	    if (pch_char(new) == '!') {
-		copy_till(where + old - 1);
-		if (R_do_defines) {
-		   fputs(not_defined, ofp);
-		   def_state = IN_IFNDEF;
-		}
-		while (pch_char(old) == '!') {
-		    if (R_do_defines) {
-			fputs(pfetch(old), ofp);
-		    }
-		    last_frozen_line++;
-		    old++;
-		}
-		if (R_do_defines) {
-		    fputs(else_defined, ofp);
-		    def_state = IN_ELSE;
+			my_exit(2);
+		} else if (pch_char(new) == '!') {
+			copy_till(where + old - 1, false);
+			if (do_defines) {
+				fputs(not_defined, ofp);
+				def_state = IN_IFNDEF;
+			}
+			while (pch_char(old) == '!') {
+				if (do_defines) {
+					fputs(pfetch(old), ofp);
+				}
+				last_frozen_line++;
+				old++;
+			}
+			if (do_defines) {
+				fputs(else_defined, ofp);
+				def_state = IN_ELSE;
+			}
+			while (pch_char(new) == '!') {
+				fputs(pfetch(new), ofp);
+				new++;
+			}
+		} else {
+			if (pch_char(new) != ' ')
+				fatal("Internal error: expected ' '\n");
+			old++;
+			new++;
+			if (do_defines && def_state != OUTSIDE) {
+				fputs(end_defined, ofp);
+				def_state = OUTSIDE;
+			}
 		}
-		while (pch_char(new) == '!') {
-		    fputs(pfetch(new), ofp);
-		    new++;
+	}
+	if (new <= pat_end && pch_char(new) == '+') {
+		copy_till(where + old - 1, false);
+		if (do_defines) {
+			if (def_state == OUTSIDE) {
+				fputs(if_defined, ofp);
+				def_state = IN_IFDEF;
+			} else if (def_state == IN_IFNDEF) {
+				fputs(else_defined, ofp);
+				def_state = IN_ELSE;
+			}
 		}
-		if (R_do_defines) {
-		    fputs(end_defined, ofp);
-		    def_state = OUTSIDE;
+		while (new <= pat_end && pch_char(new) == '+') {
+			fputs(pfetch(new), ofp);
+			new++;
 		}
-	    }
-	    else {
-		assert(pch_char(new) == ' ');
-		old++;
-		new++;
-	    }
 	}
-    }
-    if (new <= pat_end && pch_char(new) == '+') {
-	copy_till(where + old - 1);
-	if (R_do_defines) {
-	    if (def_state == OUTSIDE) {
-	    	fputs(if_defined, ofp);
-		def_state = IN_IFDEF;
-	    }
-	    else if (def_state == IN_IFNDEF) {
-		fputs(else_defined, ofp);
-		def_state = IN_ELSE;
-	    }
+	if (do_defines && def_state != OUTSIDE) {
+		fputs(end_defined, ofp);
 	}
-	while (new <= pat_end && pch_char(new) == '+') {
-	    fputs(pfetch(new), ofp);
-	    new++;
-	}
-    }
-    if (R_do_defines && def_state != OUTSIDE) {
-	fputs(end_defined, ofp);
-    }
 }
 
-/* Open the new file. */
-
-void
-init_output(name)
-char *name;
+/*
+ * Open the new file.
+ */
+static void
+init_output(const char *name)
 {
-    ofp = fopen(name, "w");
-    if (ofp == Nullfp)
-	fatal2("patch: can't create %s.\n", name);
+	ofp = fopen(name, "w");
+	if (ofp == NULL)
+		pfatal("can't create %s", name);
 }
 
-/* Open a file to put hunks we can't locate. */
-
-void
-init_reject(name)
-char *name;
+/*
+ * Open a file to put hunks we can't locate.
+ */
+static void
+init_reject(const char *name)
 {
-    rejfp = fopen(name, "w");
-    if (rejfp == Nullfp)
-	fatal2("patch: can't create %s.\n", name);
+	rejfp = fopen(name, "w");
+	if (rejfp == NULL)
+		pfatal("can't create %s", name);
 }
 
-/* Copy input file to output, up to wherever hunk is to be applied. */
-
-void
-copy_till(lastline)
-Reg1 LINENUM lastline;
+/*
+ * Copy input file to output, up to wherever hunk is to be applied.
+ * If endoffile is true, treat the last line specially since it may
+ * lack a newline.
+ */
+static void
+copy_till(LINENUM lastline, bool endoffile)
 {
-    Reg2 LINENUM R_last_frozen_line = last_frozen_line;
-
-    if (R_last_frozen_line > lastline)
-	say1("patch: misordered hunks! output will be garbled.\n");
-    while (R_last_frozen_line < lastline) {
-	dump_line(++R_last_frozen_line);
-    }
-    last_frozen_line = R_last_frozen_line;
+	if (last_frozen_line > lastline)
+		fatal("misordered hunks! output would be garbled\n");
+	while (last_frozen_line < lastline) {
+		if (++last_frozen_line == lastline && endoffile)
+			dump_line(last_frozen_line, !last_line_missing_eol);
+		else
+			dump_line(last_frozen_line, true);
+	}
 }
 
-/* Finish copying the input file to the output file. */
-
-void
-spew_output()
+/*
+ * Finish copying the input file to the output file.
+ */
+static void
+spew_output(void)
 {
 #ifdef DEBUGGING
-    if (debug & 256)
-	say3("il=%ld lfl=%ld\n",input_lines,last_frozen_line);
+	if (debug & 256)
+		say("il=%ld lfl=%ld\n", input_lines, last_frozen_line);
 #endif
-    if (input_lines)
-	copy_till(input_lines);		/* dump remainder of file */
-    Fclose(ofp);
-    ofp = Nullfp;
+	if (input_lines)
+		copy_till(input_lines, true);	/* dump remainder of file */
+	fclose(ofp);
+	ofp = NULL;
 }
 
-/* Copy one line from input to output. */
-
-void
-dump_line(line)
-LINENUM line;
+/*
+ * Copy one line from input to output.
+ */
+static void
+dump_line(LINENUM line, bool write_newline)
 {
-    Reg1 char *s;
-    Reg2 char R_newline = '\n';
-
-    /* Note: string is not null terminated. */
-    for (s=ifetch(line, 0); putc(*s, ofp) != R_newline; s++) ;
+	char	*s;
+
+	s = ifetch(line, 0);
+	if (s == NULL)
+		return;
+	/* Note: string is not NUL terminated. */
+	for (; *s != '\n'; s++)
+		putc(*s, ofp);
+	if (write_newline)
+		putc('\n', ofp);
 }
 
-/* Does the patch pattern match at line base+offset? */
-
-bool
-patch_match(base, offset, fuzz)
-LINENUM base;
-LINENUM offset;
-LINENUM fuzz;
+/*
+ * Does the patch pattern match at line base+offset?
+ */
+static bool
+patch_match(LINENUM base, LINENUM offset, LINENUM fuzz)
 {
-    Reg1 LINENUM pline = 1 + fuzz;
-    Reg2 LINENUM iline;
-    Reg3 LINENUM pat_lines = pch_ptrn_lines() - fuzz;
-
-    for (iline=base+offset+fuzz; pline <= pat_lines; pline++,iline++) {
-	if (canonicalize) {
-	    if (!similar(ifetch(iline, (offset >= 0)),
-			 pfetch(pline),
-			 pch_line_len(pline) ))
-		return FALSE;
+	LINENUM		pline = 1 + fuzz;
+	LINENUM		iline;
+	LINENUM		pat_lines = pch_ptrn_lines() - fuzz;
+	const char	*ilineptr;
+	const char	*plineptr;
+	short		plinelen;
+
+	for (iline = base + offset + fuzz; pline <= pat_lines; pline++, iline++) {
+		ilineptr = ifetch(iline, offset >= 0);
+		if (ilineptr == NULL)
+			return false;
+		plineptr = pfetch(pline);
+		plinelen = pch_line_len(pline);
+		if (canonicalize) {
+			if (!similar(ilineptr, plineptr, plinelen))
+				return false;
+		} else if (strnNE(ilineptr, plineptr, plinelen))
+			return false;
+		if (iline == input_lines) {
+			/*
+			 * We are looking at the last line of the file.
+			 * If the file has no eol, the patch line should
+			 * not have one either and vice-versa. Note that
+			 * plinelen > 0.
+			 */
+			if (last_line_missing_eol) {
+				if (plineptr[plinelen - 1] == '\n')
+					return false;
+			} else {
+				if (plineptr[plinelen - 1] != '\n')
+					return false;
+			}
+		}
 	}
-	else if (strnNE(ifetch(iline, (offset >= 0)),
-		   pfetch(pline),
-		   pch_line_len(pline) ))
-	    return FALSE;
-    }
-    return TRUE;
+	return true;
 }
 
-/* Do two lines match with canonicalized white space? */
-
-bool
-similar(a,b,len)
-Reg1 char *a;
-Reg2 char *b;
-Reg3 int len;
+/*
+ * Do two lines match with canonicalized white space?
+ */
+static bool
+similar(const char *a, const char *b, int len)
 {
-    while (len) {
-	if (isspace(*b)) {		/* whitespace (or \n) to match? */
-	    if (!isspace(*a))		/* no corresponding whitespace? */
-		return FALSE;
-	    while (len && isspace(*b) && *b != '\n')
-		b++,len--;		/* skip pattern whitespace */
-	    while (isspace(*a) && *a != '\n')
-		a++;			/* skip target whitespace */
-	    if (*a == '\n' || *b == '\n')
-		return (*a == *b);	/* should end in sync */
+	while (len) {
+		if (isspace(*b)) {	/* whitespace (or \n) to match? */
+			if (!isspace(*a))	/* no corresponding whitespace? */
+				return false;
+			while (len && isspace(*b) && *b != '\n')
+				b++, len--;	/* skip pattern whitespace */
+			while (isspace(*a) && *a != '\n')
+				a++;	/* skip target whitespace */
+			if (*a == '\n' || *b == '\n')
+				return (*a == *b);	/* should end in sync */
+		} else if (*a++ != *b++)	/* match non-whitespace chars */
+			return false;
+		else
+			len--;	/* probably not necessary */
 	}
-	else if (*a++ != *b++)		/* match non-whitespace chars */
-	    return FALSE;
-	else
-	    len--;			/* probably not necessary */
-    }
-    return TRUE;			/* actually, this is not reached */
-					/* since there is always a \n */
-}
-
-/* Exit with cleanup. */
-
-void
-my_exit(status)
-int status;
-{
-    Unlink(TMPINNAME);
-    if (!toutkeep) {
-	Unlink(TMPOUTNAME);
-    }
-    if (!trejkeep) {
-	Unlink(TMPREJNAME);
-    }
-    Unlink(TMPPATNAME);
-    exit(status);
+	return true;		/* actually, this is not reached */
+	/* since there is always a \n */
 }
diff --git a/usr.bin/patch/pathnames.h b/usr.bin/patch/pathnames.h
new file mode 100644
index 0000000..397e3fa
--- /dev/null
+++ b/usr.bin/patch/pathnames.h
@@ -0,0 +1,11 @@
+/*	$OpenBSD: pathnames.h,v 1.1 2003/07/29 20:10:17 millert Exp $	*/
+
+/*
+ * Placed in the public domain by Todd C. Miller <Todd.Miller@courtesan.com>
+ * on July 29, 2003.
+ */
+
+#include <paths.h>
+
+#define	_PATH_ED		"/bin/ed"
+#define	_PATH_MKDIR		"/bin/mkdir"
diff --git a/usr.bin/patch/pch.c b/usr.bin/patch/pch.c
index 8837212..bfdb176 100644
--- a/usr.bin/patch/pch.c
+++ b/usr.bin/patch/pch.c
@@ -1,1108 +1,1549 @@
-/* $Header: pch.c,v 2.0.1.6 87/06/04 16:18:13 lwall Exp $
- *
- * $Log:	pch.c,v $
- * Revision 2.0.1.6  87/06/04  16:18:13  lwall
- * pch_swap didn't swap p_bfake and p_efake.
- * 
- * Revision 2.0.1.5  87/01/30  22:47:42  lwall
- * Improved responses to mangled patches.
- * 
- * Revision 2.0.1.4  87/01/05  16:59:53  lwall
- * New-style context diffs caused double call to free().
- * 
- * Revision 2.0.1.3  86/11/14  10:08:33  lwall
- * Fixed problem where a long pattern wouldn't grow the hunk.
- * Also restored p_input_line when backtracking so error messages are right.
+/*	$OpenBSD: pch.c,v 1.34 2004/07/09 19:13:46 otto Exp $	*/
+
+/*
+ * patch - a program to apply diffs to original files
  * 
- * Revision 2.0.1.2  86/11/03  17:49:52  lwall
- * New-style delete triggers spurious assertion error.
+ * Copyright 1986, Larry Wall
  * 
- * Revision 2.0.1.1  86/10/29  15:52:08  lwall
- * Could falsely report new-style context diff.
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following condition is met:
+ * 1. Redistributions of source code must retain the above copyright notice,
+ * this condition and the following disclaimer.
  * 
- * Revision 2.0  86/09/17  15:39:37  lwall
- * Baseline for netwide release.
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
  * 
+ * -C option added in 1998, original code by Marc Espie, based on FreeBSD
+ * behaviour
  */
 
-#include "EXTERN.h"
+#ifndef lint
+static const char rcsid[] = "$OpenBSD: pch.c,v 1.34 2004/07/09 19:13:46 otto Exp $";
+#endif /* not lint */
+
+#include <sys/types.h>
+#include <sys/stat.h>
+
+#include <ctype.h>
+#include <libgen.h>
+#include <limits.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
 #include "common.h"
 #include "util.h"
-#include "INTERN.h"
 #include "pch.h"
+#include "pathnames.h"
 
 /* Patch (diff listing) abstract type. */
 
-static long p_filesize;			/* size of the patch file */
-static LINENUM p_first;			/* 1st line number */
-static LINENUM p_newfirst;		/* 1st line number of replacement */
-static LINENUM p_ptrn_lines;		/* # lines in pattern */
-static LINENUM p_repl_lines;		/* # lines in replacement text */
-static LINENUM p_end = -1;		/* last line in hunk */
-static LINENUM p_max;			/* max allowed value of p_end */
-static LINENUM p_context = 3;		/* # of context lines */
-static LINENUM p_input_line = 0;	/* current line # from patch file */
-static char **p_line = Null(char**);	/* the text of the hunk */
-static short *p_len = Null(short*);	/* length of each line */
-static char *p_char = Nullch;		/* +, -, and ! */
-static int hunkmax = INITHUNKMAX;	/* size of above arrays to begin with */
-static int p_indent;			/* indent to patch */
-static LINENUM p_base;			/* where to intuit this time */
-static LINENUM p_bline;			/* line # of p_base */
-static LINENUM p_start;			/* where intuit found a patch */
-static LINENUM p_sline;			/* and the line number for it */
-static LINENUM p_hunk_beg;		/* line number of current hunk */
-static LINENUM p_efake = -1;		/* end of faked up lines--don't free */
-static LINENUM p_bfake = -1;		/* beg of faked up lines */
-
-/* Prepare to look for the next patch in the patch file. */
-
+static long	p_filesize;	/* size of the patch file */
+static LINENUM	p_first;	/* 1st line number */
+static LINENUM	p_newfirst;	/* 1st line number of replacement */
+static LINENUM	p_ptrn_lines;	/* # lines in pattern */
+static LINENUM	p_repl_lines;	/* # lines in replacement text */
+static LINENUM	p_end = -1;	/* last line in hunk */
+static LINENUM	p_max;		/* max allowed value of p_end */
+static LINENUM	p_context = 3;	/* # of context lines */
+static LINENUM	p_input_line = 0;	/* current line # from patch file */
+static char	**p_line = NULL;/* the text of the hunk */
+static short	*p_len = NULL;	/* length of each line */
+static char	*p_char = NULL;	/* +, -, and ! */
+static int	hunkmax = INITHUNKMAX;	/* size of above arrays to begin with */
+static int	p_indent;	/* indent to patch */
+static LINENUM	p_base;		/* where to intuit this time */
+static LINENUM	p_bline;	/* line # of p_base */
+static LINENUM	p_start;	/* where intuit found a patch */
+static LINENUM	p_sline;	/* and the line number for it */
+static LINENUM	p_hunk_beg;	/* line number of current hunk */
+static LINENUM	p_efake = -1;	/* end of faked up lines--don't free */
+static LINENUM	p_bfake = -1;	/* beg of faked up lines */
+static FILE	*pfp = NULL;	/* patch file pointer */
+static char	*bestguess = NULL;	/* guess at correct filename */
+
+static void	grow_hunkmax(void);
+static int	intuit_diff_type(void);
+static void	next_intuit_at(LINENUM, LINENUM);
+static void	skip_to(LINENUM, LINENUM);
+static char	*pgets(char *, int, FILE *);
+static char	*best_name(const struct file_name *, bool);
+static char	*posix_name(const struct file_name *, bool);
+static size_t	num_components(const char *);
+
+/*
+ * Prepare to look for the next patch in the patch file.
+ */
 void
-re_patch()
+re_patch(void)
 {
-    p_first = Nulline;
-    p_newfirst = Nulline;
-    p_ptrn_lines = Nulline;
-    p_repl_lines = Nulline;
-    p_end = (LINENUM)-1;
-    p_max = Nulline;
-    p_indent = 0;
+	p_first = 0;
+	p_newfirst = 0;
+	p_ptrn_lines = 0;
+	p_repl_lines = 0;
+	p_end = (LINENUM) - 1;
+	p_max = 0;
+	p_indent = 0;
 }
 
-/* Open the patch file at the beginning of time. */
-
+/*
+ * Open the patch file at the beginning of time.
+ */
 void
-open_patch_file(filename)
-char *filename;
+open_patch_file(const char *filename)
 {
-    if (filename == Nullch || !*filename || strEQ(filename, "-")) {
-	pfp = fopen(TMPPATNAME, "w");
-	if (pfp == Nullfp)
-	    fatal2("patch: can't create %s.\n", TMPPATNAME);
-	while (fgets(buf, sizeof buf, stdin) != Nullch)
-	    fputs(buf, pfp);
-	Fclose(pfp);
-	filename = TMPPATNAME;
-    }
-    pfp = fopen(filename, "r");
-    if (pfp == Nullfp)
-	fatal2("patch file %s not found\n", filename);
-    Fstat(fileno(pfp), &filestat);
-    p_filesize = filestat.st_size;
-    next_intuit_at(0L,1L);			/* start at the beginning */
-    set_hunkmax();
+	struct stat filestat;
+
+	if (filename == NULL || *filename == '\0' || strEQ(filename, "-")) {
+		pfp = fopen(TMPPATNAME, "w");
+		if (pfp == NULL)
+			pfatal("can't create %s", TMPPATNAME);
+		while (fgets(buf, sizeof buf, stdin) != NULL)
+			fputs(buf, pfp);
+		fclose(pfp);
+		filename = TMPPATNAME;
+	}
+	pfp = fopen(filename, "r");
+	if (pfp == NULL)
+		pfatal("patch file %s not found", filename);
+	fstat(fileno(pfp), &filestat);
+	p_filesize = filestat.st_size;
+	next_intuit_at(0L, 1L);	/* start at the beginning */
+	set_hunkmax();
 }
 
-/* Make sure our dynamically realloced tables are malloced to begin with. */
-
+/*
+ * Make sure our dynamically realloced tables are malloced to begin with.
+ */
 void
-set_hunkmax()
+set_hunkmax(void)
 {
-#ifndef lint
-    if (p_line == Null(char**))
-	p_line = (char**) malloc((MEM)hunkmax * sizeof(char *));
-    if (p_len == Null(short*))
-	p_len  = (short*) malloc((MEM)hunkmax * sizeof(short));
-#endif
-    if (p_char == Nullch)
-	p_char = (char*)  malloc((MEM)hunkmax * sizeof(char));
+	if (p_line == NULL)
+		p_line = malloc((size_t) hunkmax * sizeof(char *));
+	if (p_len == NULL)
+		p_len = malloc((size_t) hunkmax * sizeof(short));
+	if (p_char == NULL)
+		p_char = malloc((size_t) hunkmax * sizeof(char));
 }
 
-/* Enlarge the arrays containing the current hunk of patch. */
-
-void
-grow_hunkmax()
+/*
+ * Enlarge the arrays containing the current hunk of patch.
+ */
+static void
+grow_hunkmax(void)
 {
-    hunkmax *= 2;
-    /* 
-     * Note that on most systems, only the p_line array ever gets fresh memory
-     * since p_len can move into p_line's old space, and p_char can move into
-     * p_len's old space.  Not on PDP-11's however.  But it doesn't matter.
-     */
-    assert(p_line != Null(char**) && p_len != Null(short*) && p_char != Nullch);
-#ifndef lint
-    p_line = (char**) realloc((char*)p_line, (MEM)hunkmax * sizeof(char *));
-    p_len  = (short*) realloc((char*)p_len,  (MEM)hunkmax * sizeof(short));
-    p_char = (char*)  realloc((char*)p_char, (MEM)hunkmax * sizeof(char));
-#endif
-    if (p_line != Null(char**) && p_len != Null(short*) && p_char != Nullch)
-	return;
-    if (!using_plan_a)
-	fatal1("patch: out of memory (grow_hunkmax)\n");
-    out_of_mem = TRUE;		/* whatever is null will be allocated again */
+	int		new_hunkmax;
+	char 		**new_p_line;
+	short		*new_p_len;
+	char		*new_p_char;
+
+	new_hunkmax = hunkmax * 2;
+
+	if (p_line == NULL || p_len == NULL || p_char == NULL)
+		fatal("Internal memory allocation error\n");
+
+	new_p_line = realloc(p_line, new_hunkmax * sizeof(char *));
+	if (new_p_line == NULL)
+		free(p_line);
+
+	new_p_len = realloc(p_len, new_hunkmax * sizeof(short));
+	if (new_p_len == NULL)
+		free(p_len);
+
+	new_p_char = realloc(p_char, new_hunkmax * sizeof(char));
+	if (new_p_char == NULL)
+		free(p_char);
+
+	p_char = new_p_char;
+	p_len = new_p_len;
+	p_line = new_p_line;
+
+	if (p_line != NULL && p_len != NULL && p_char != NULL) {
+		hunkmax = new_hunkmax;
+		return;
+	}
+
+	if (!using_plan_a)
+		fatal("out of memory\n");
+	out_of_mem = true;	/* whatever is null will be allocated again */
 				/* from within plan_a(), of all places */
 }
 
 /* True if the remainder of the patch file contains a diff of some sort. */
 
 bool
-there_is_another_patch()
+there_is_another_patch(void)
 {
-    if (p_base != 0L && p_base >= p_filesize) {
-	if (verbose)
-	    say1("done\n");
-	return FALSE;
-    }
-    if (verbose)
-	say1("Hmm...");
-    diff_type = intuit_diff_type();
-    if (!diff_type) {
-	if (p_base != 0L) {
-	    if (verbose)
-		say1("  Ignoring the trailing garbage.\ndone\n");
-	}
-	else
-	    say1("  I can't seem to find a patch in there anywhere.\n");
-	return FALSE;
-    }
-    if (verbose)
-	say3("  %sooks like %s to me...\n",
-	    (p_base == 0L ? "L" : "The next patch l"),
-	    diff_type == CONTEXT_DIFF ? "a context diff" :
-	    diff_type == NEW_CONTEXT_DIFF ? "a new-style context diff" :
-	    diff_type == NORMAL_DIFF ? "a normal diff" :
-	    "an ed script" );
-    if (p_indent && verbose)
-	say3("(Patch is indented %d space%s.)\n", p_indent, p_indent==1?"":"s");
-    skip_to(p_start,p_sline);
-    while (filearg[0] == Nullch) {
-	if (force) {
-	    say1("No file to patch.  Skipping...\n");
-	    filearg[0] = savestr(bestguess);
-	    return TRUE;
+	bool exists = false;
+
+	if (p_base != 0L && p_base >= p_filesize) {
+		if (verbose)
+			say("done\n");
+		return false;
 	}
-	ask1("File to patch: ");
-	if (*buf != '\n') {
-	    if (bestguess)
-		free(bestguess);
-	    bestguess = savestr(buf);
-	    filearg[0] = fetchname(buf, 0, FALSE);
+	if (verbose)
+		say("Hmm...");
+	diff_type = intuit_diff_type();
+	if (!diff_type) {
+		if (p_base != 0L) {
+			if (verbose)
+				say("  Ignoring the trailing garbage.\ndone\n");
+		} else
+			say("  I can't seem to find a patch in there anywhere.\n");
+		return false;
 	}
-	if (filearg[0] == Nullch) {
-	    ask1("No file found--skip this patch? [n] ");
-	    if (*buf != 'y') {
-		continue;
-	    }
-	    if (verbose)
-		say1("Skipping patch...\n");
-	    filearg[0] = fetchname(bestguess, 0, TRUE);
-	    skip_rest_of_patch = TRUE;
-	    return TRUE;
+	if (verbose)
+		say("  %sooks like %s to me...\n",
+		    (p_base == 0L ? "L" : "The next patch l"),
+		    diff_type == UNI_DIFF ? "a unified diff" :
+		    diff_type == CONTEXT_DIFF ? "a context diff" :
+		diff_type == NEW_CONTEXT_DIFF ? "a new-style context diff" :
+		    diff_type == NORMAL_DIFF ? "a normal diff" :
+		    "an ed script");
+	if (p_indent && verbose)
+		say("(Patch is indented %d space%s.)\n", p_indent,
+		    p_indent == 1 ? "" : "s");
+	skip_to(p_start, p_sline);
+	while (filearg[0] == NULL) {
+		if (force || batch) {
+			say("No file to patch.  Skipping...\n");
+			filearg[0] = savestr(bestguess);
+			skip_rest_of_patch = true;
+			return true;
+		}
+		ask("File to patch: ");
+		if (*buf != '\n') {
+			free(bestguess);
+			bestguess = savestr(buf);
+			filearg[0] = fetchname(buf, &exists, 0);
+		}
+		if (!exists) {
+			ask("No file found--skip this patch? [n] ");
+			if (*buf != 'y')
+				continue;
+			if (verbose)
+				say("Skipping patch...\n");
+			free(filearg[0]);
+			filearg[0] = fetchname(bestguess, &exists, 0);
+			skip_rest_of_patch = true;
+			return true;
+		}
 	}
-    }
-    return TRUE;
+	return true;
 }
 
 /* Determine what kind of diff is in the remaining part of the patch file. */
 
-int
-intuit_diff_type()
+static int
+intuit_diff_type(void)
 {
-    Reg4 long this_line = 0;
-    Reg5 long previous_line;
-    Reg6 long first_command_line = -1;
-    long fcl_line;
-    Reg7 bool last_line_was_command = FALSE;
-    Reg8 bool this_is_a_command = FALSE;
-    Reg9 bool stars_last_line = FALSE;
-    Reg10 bool stars_this_line = FALSE;
-    Reg3 int indent;
-    Reg1 char *s;
-    Reg2 char *t;
-    char *indtmp = Nullch;
-    char *oldtmp = Nullch;
-    char *newtmp = Nullch;
-    char *indname = Nullch;
-    char *oldname = Nullch;
-    char *newname = Nullch;
-    Reg11 int retval;
-    bool no_filearg = (filearg[0] == Nullch);
-
-    ok_to_create_file = FALSE;
-    Fseek(pfp, p_base, 0);
-    p_input_line = p_bline - 1;
-    for (;;) {
-	previous_line = this_line;
-	last_line_was_command = this_is_a_command;
-	stars_last_line = stars_this_line;
-	this_line = ftell(pfp);
-	indent = 0;
-	p_input_line++;
-	if (fgets(buf, sizeof buf, pfp) == Nullch) {
-	    if (first_command_line >= 0L) {
-					/* nothing but deletes!? */
-		p_start = first_command_line;
-		p_sline = fcl_line;
-		retval = ED_DIFF;
-		goto scan_exit;
-	    }
-	    else {
-		p_start = this_line;
-		p_sline = p_input_line;
-		retval = 0;
-		goto scan_exit;
-	    }
-	}
-	for (s = buf; *s == ' ' || *s == '\t'; s++) {
-	    if (*s == '\t')
-		indent += 8 - (indent % 8);
-	    else
-		indent++;
-	}
-	for (t=s; isdigit(*t) || *t == ','; t++) ; 
-	this_is_a_command = (isdigit(*s) &&
-	  (*t == 'd' || *t == 'c' || *t == 'a') );
-	if (first_command_line < 0L && this_is_a_command) { 
-	    first_command_line = this_line;
-	    fcl_line = p_input_line;
-	    p_indent = indent;		/* assume this for now */
-	}
-	if (!stars_last_line && strnEQ(s, "*** ", 4))
-	    oldtmp = savestr(s+4);
-	else if (strnEQ(s, "--- ", 4))
-	    newtmp = savestr(s+4);
-	else if (strnEQ(s, "Index:", 6))
-	    indtmp = savestr(s+6);
-	else if (strnEQ(s, "Prereq:", 7)) {
-	    for (t=s+7; isspace(*t); t++) ;
-	    revision = savestr(t);
-	    for (t=revision; *t && !isspace(*t); t++) ;
-	    *t = '\0';
-	    if (!*revision) {
-		free(revision);
-		revision = Nullch;
-	    }
-	}
-	if ((!diff_type || diff_type == ED_DIFF) &&
-	  first_command_line >= 0L &&
-	  strEQ(s, ".\n") ) {
-	    p_indent = indent;
-	    p_start = first_command_line;
-	    p_sline = fcl_line;
-	    retval = ED_DIFF;
-	    goto scan_exit;
-	}
-	stars_this_line = strnEQ(s, "********", 8);
-	if ((!diff_type || diff_type == CONTEXT_DIFF) && stars_last_line &&
-		 strnEQ(s, "*** ", 4)) {
-	    if (!atol(s+4))
-		ok_to_create_file = TRUE;
-	    /* if this is a new context diff the character just before */
-	    /* the newline is a '*'. */
-	    while (*s != '\n')
-		s++;
-	    p_indent = indent;
-	    p_start = previous_line;
-	    p_sline = p_input_line - 1;
-	    retval = (*(s-1) == '*' ? NEW_CONTEXT_DIFF : CONTEXT_DIFF);
-	    goto scan_exit;
+	long	this_line = 0, previous_line;
+	long	first_command_line = -1;
+	LINENUM	fcl_line = -1;
+	bool	last_line_was_command = false, this_is_a_command = false;
+	bool	stars_last_line = false, stars_this_line = false;
+	char	*s, *t;
+	int	indent, retval;
+	struct file_name names[MAX_FILE];
+
+	memset(names, 0, sizeof(names));
+	ok_to_create_file = false;
+	fseek(pfp, p_base, SEEK_SET);
+	p_input_line = p_bline - 1;
+	for (;;) {
+		previous_line = this_line;
+		last_line_was_command = this_is_a_command;
+		stars_last_line = stars_this_line;
+		this_line = ftell(pfp);
+		indent = 0;
+		p_input_line++;
+		if (fgets(buf, sizeof buf, pfp) == NULL) {
+			if (first_command_line >= 0L) {
+				/* nothing but deletes!? */
+				p_start = first_command_line;
+				p_sline = fcl_line;
+				retval = ED_DIFF;
+				goto scan_exit;
+			} else {
+				p_start = this_line;
+				p_sline = p_input_line;
+				retval = 0;
+				goto scan_exit;
+			}
+		}
+		for (s = buf; *s == ' ' || *s == '\t' || *s == 'X'; s++) {
+			if (*s == '\t')
+				indent += 8 - (indent % 8);
+			else
+				indent++;
+		}
+		for (t = s; isdigit(*t) || *t == ','; t++)
+			;
+		this_is_a_command = (isdigit(*s) &&
+		    (*t == 'd' || *t == 'c' || *t == 'a'));
+		if (first_command_line < 0L && this_is_a_command) {
+			first_command_line = this_line;
+			fcl_line = p_input_line;
+			p_indent = indent;	/* assume this for now */
+		}
+		if (!stars_last_line && strnEQ(s, "*** ", 4))
+			names[OLD_FILE].path = fetchname(s + 4,
+			    &names[OLD_FILE].exists, strippath);
+		else if (strnEQ(s, "--- ", 4))
+			names[NEW_FILE].path = fetchname(s + 4,
+			    &names[NEW_FILE].exists, strippath);
+		else if (strnEQ(s, "+++ ", 4))
+			/* pretend it is the old name */
+			names[OLD_FILE].path = fetchname(s + 4,
+			    &names[OLD_FILE].exists, strippath);
+		else if (strnEQ(s, "Index:", 6))
+			names[INDEX_FILE].path = fetchname(s + 6,
+			    &names[INDEX_FILE].exists, strippath);
+		else if (strnEQ(s, "Prereq:", 7)) {
+			for (t = s + 7; isspace(*t); t++)
+				;
+			revision = savestr(t);
+			for (t = revision; *t && !isspace(*t); t++)
+				;
+			*t = '\0';
+			if (*revision == '\0') {
+				free(revision);
+				revision = NULL;
+			}
+		}
+		if ((!diff_type || diff_type == ED_DIFF) &&
+		    first_command_line >= 0L &&
+		    strEQ(s, ".\n")) {
+			p_indent = indent;
+			p_start = first_command_line;
+			p_sline = fcl_line;
+			retval = ED_DIFF;
+			goto scan_exit;
+		}
+		if ((!diff_type || diff_type == UNI_DIFF) && strnEQ(s, "@@ -", 4)) {
+			if (strnEQ(s + 4, "0,0", 3))
+				ok_to_create_file = true;
+			p_indent = indent;
+			p_start = this_line;
+			p_sline = p_input_line;
+			retval = UNI_DIFF;
+			goto scan_exit;
+		}
+		stars_this_line = strnEQ(s, "********", 8);
+		if ((!diff_type || diff_type == CONTEXT_DIFF) && stars_last_line &&
+		    strnEQ(s, "*** ", 4)) {
+			if (atol(s + 4) == 0)
+				ok_to_create_file = true;
+			/*
+			 * If this is a new context diff the character just
+			 * before the newline is a '*'.
+			 */
+			while (*s != '\n')
+				s++;
+			p_indent = indent;
+			p_start = previous_line;
+			p_sline = p_input_line - 1;
+			retval = (*(s - 1) == '*' ? NEW_CONTEXT_DIFF : CONTEXT_DIFF);
+			goto scan_exit;
+		}
+		if ((!diff_type || diff_type == NORMAL_DIFF) &&
+		    last_line_was_command &&
+		    (strnEQ(s, "< ", 2) || strnEQ(s, "> ", 2))) {
+			p_start = previous_line;
+			p_sline = p_input_line - 1;
+			p_indent = indent;
+			retval = NORMAL_DIFF;
+			goto scan_exit;
+		}
 	}
-	if ((!diff_type || diff_type == NORMAL_DIFF) && 
-	  last_line_was_command &&
-	  (strnEQ(s, "< ", 2) || strnEQ(s, "> ", 2)) ) {
-	    p_start = previous_line;
-	    p_sline = p_input_line - 1;
-	    p_indent = indent;
-	    retval = NORMAL_DIFF;
-	    goto scan_exit;
+scan_exit:
+	if (retval == UNI_DIFF) {
+		/* unswap old and new */
+		struct file_name tmp = names[OLD_FILE];
+		names[OLD_FILE] = names[NEW_FILE];
+		names[NEW_FILE] = tmp;
 	}
-    }
-  scan_exit:
-    if (no_filearg) {
-	if (indtmp != Nullch)
-	    indname = fetchname(indtmp, strippath, ok_to_create_file);
-	if (oldtmp != Nullch)
-	    oldname = fetchname(oldtmp, strippath, ok_to_create_file);
-	if (newtmp != Nullch)
-	    newname = fetchname(newtmp, strippath, ok_to_create_file);
-	if (oldname && newname) {
-	    if (strlen(oldname) < strlen(newname))
-		filearg[0] = savestr(oldname);
-	    else
-		filearg[0] = savestr(newname);
+	if (filearg[0] == NULL) {
+		if (posix)
+			filearg[0] = posix_name(names, ok_to_create_file);
+		else {
+			/* Ignore the Index: name for context diffs, like GNU */
+			if (names[OLD_FILE].path != NULL ||
+			    names[NEW_FILE].path != NULL) {
+				free(names[INDEX_FILE].path);
+				names[INDEX_FILE].path = NULL;
+			}
+			filearg[0] = best_name(names, ok_to_create_file);
+		}
 	}
-	else if (oldname)
-	    filearg[0] = savestr(oldname);
-	else if (newname)
-	    filearg[0] = savestr(newname);
-	else if (indname)
-	    filearg[0] = savestr(indname);
-    }
-    if (bestguess) {
+
 	free(bestguess);
-	bestguess = Nullch;
-    }
-    if (filearg[0] != Nullch)
-	bestguess = savestr(filearg[0]);
-    else if (indtmp != Nullch)
-	bestguess = fetchname(indtmp, strippath, TRUE);
-    else {
-	if (oldtmp != Nullch)
-	    oldname = fetchname(oldtmp, strippath, TRUE);
-	if (newtmp != Nullch)
-	    newname = fetchname(newtmp, strippath, TRUE);
-	if (oldname && newname) {
-	    if (strlen(oldname) < strlen(newname))
-		bestguess = savestr(oldname);
-	    else
-		bestguess = savestr(newname);
+	bestguess = NULL;
+	if (filearg[0] != NULL)
+		bestguess = savestr(filearg[0]);
+	else if (!ok_to_create_file) {
+		/*
+		 * We don't want to create a new file but we need a
+		 * filename to set bestguess.  Avoid setting filearg[0]
+		 * so the file is not created automatically.
+		 */
+		if (posix)
+			bestguess = posix_name(names, true);
+		else
+			bestguess = best_name(names, true);
 	}
-	else if (oldname)
-	    bestguess = savestr(oldname);
-	else if (newname)
-	    bestguess = savestr(newname);
-    }
-    if (indtmp != Nullch)
-	free(indtmp);
-    if (oldtmp != Nullch)
-	free(oldtmp);
-    if (newtmp != Nullch)
-	free(newtmp);
-    if (indname != Nullch)
-	free(indname);
-    if (oldname != Nullch)
-	free(oldname);
-    if (newname != Nullch)
-	free(newname);
-    return retval;
+	free(names[OLD_FILE].path);
+	free(names[NEW_FILE].path);
+	free(names[INDEX_FILE].path);
+	return retval;
 }
 
-/* Remember where this patch ends so we know where to start up again. */
+/*
+ * Remember where this patch ends so we know where to start up again.
+ */
+static void
+next_intuit_at(LINENUM file_pos, LINENUM file_line)
+{
+	p_base = file_pos;
+	p_bline = file_line;
+}
 
-void
-next_intuit_at(file_pos,file_line)
-long file_pos;
-long file_line;
+/*
+ * Basically a verbose fseek() to the actual diff listing.
+ */
+static void
+skip_to(LINENUM file_pos, LINENUM file_line)
 {
-    p_base = file_pos;
-    p_bline = file_line;
+	char	*ret;
+
+	if (p_base > file_pos)
+		fatal("Internal error: seek %ld>%ld\n", p_base, file_pos);
+	if (verbose && p_base < file_pos) {
+		fseek(pfp, p_base, SEEK_SET);
+		say("The text leading up to this was:\n--------------------------\n");
+		while (ftell(pfp) < file_pos) {
+			ret = fgets(buf, sizeof buf, pfp);
+			if (ret == NULL)
+				fatal("Unexpected end of file\n");
+			say("|%s", buf);
+		}
+		say("--------------------------\n");
+	} else
+		fseek(pfp, file_pos, SEEK_SET);
+	p_input_line = file_line - 1;
 }
 
-/* Basically a verbose fseek() to the actual diff listing. */
+/* Make this a function for better debugging.  */
+static void
+malformed(void)
+{
+	fatal("malformed patch at line %ld: %s", p_input_line, buf);
+	/* about as informative as "Syntax error" in C */
+}
 
-void
-skip_to(file_pos,file_line)
-long file_pos;
-long file_line;
+/*
+ * True if the line has been discarded (i.e. it is a line saying
+ *  "\ No newline at end of file".)
+ */
+static bool
+remove_special_line(void)
 {
-    char *ret;
-
-    assert(p_base <= file_pos);
-    if (verbose && p_base < file_pos) {
-	Fseek(pfp, p_base, 0);
-	say1("The text leading up to this was:\n--------------------------\n");
-	while (ftell(pfp) < file_pos) {
-	    ret = fgets(buf, sizeof buf, pfp);
-	    assert(ret != Nullch);
-	    say2("|%s", buf);
+	int	c;
+
+	c = fgetc(pfp);
+	if (c == '\\') {
+		do {
+			c = fgetc(pfp);
+		} while (c != EOF && c != '\n');
+
+		return true;
 	}
-	say1("--------------------------\n");
-    }
-    else
-	Fseek(pfp, file_pos, 0);
-    p_input_line = file_line - 1;
-}
+	if (c != EOF)
+		fseek(pfp, -1L, SEEK_CUR);
 
-/* True if there is more of the current diff listing to process. */
+	return false;
+}
 
+/*
+ * True if there is more of the current diff listing to process.
+ */
 bool
-another_hunk()
+another_hunk(void)
 {
-    Reg1 char *s;
-    Reg8 char *ret;
-    Reg2 int context = 0;
-
-    while (p_end >= 0) {
-	if (p_end == p_efake)
-	    p_end = p_bfake;		/* don't free twice */
-	else
-	    free(p_line[p_end]);
-	p_end--;
-    }
-    assert(p_end == -1);
-    p_efake = -1;
-
-    p_max = hunkmax;			/* gets reduced when --- found */
-    if (diff_type == CONTEXT_DIFF || diff_type == NEW_CONTEXT_DIFF) {
-	long line_beginning = ftell(pfp);
-					/* file pos of the current line */
-	LINENUM repl_beginning = 0;	/* index of --- line */
-	Reg4 LINENUM fillcnt = 0;	/* #lines of missing ptrn or repl */
-	Reg5 LINENUM fillsrc;		/* index of first line to copy */
-	Reg6 LINENUM filldst;		/* index of first missing line */
-	bool ptrn_spaces_eaten = FALSE;	/* ptrn was slightly misformed */
-	Reg9 bool repl_could_be_missing = TRUE;
-					/* no + or ! lines in this hunk */
-	bool repl_missing = FALSE;	/* we are now backtracking */
-	long repl_backtrack_position = 0;
-					/* file pos of first repl line */
-	LINENUM repl_patch_line;	/* input line number for same */
-	Reg7 LINENUM ptrn_copiable = 0;
-					/* # of copiable lines in ptrn */
-
-	ret = pgets(buf, sizeof buf, pfp);
-	p_input_line++;
-	if (ret == Nullch || strnNE(buf, "********", 8)) {
-	    next_intuit_at(line_beginning,p_input_line);
-	    return FALSE;
+	long	line_beginning;			/* file pos of the current line */
+	LINENUM	repl_beginning;			/* index of --- line */
+	LINENUM	fillcnt;			/* #lines of missing ptrn or repl */
+	LINENUM	fillsrc;			/* index of first line to copy */
+	LINENUM	filldst;			/* index of first missing line */
+	bool	ptrn_spaces_eaten;		/* ptrn was slightly misformed */
+	bool	repl_could_be_missing;		/* no + or ! lines in this hunk */
+	bool	repl_missing;			/* we are now backtracking */
+	long	repl_backtrack_position;	/* file pos of first repl line */
+	LINENUM	repl_patch_line;		/* input line number for same */
+	LINENUM	ptrn_copiable;			/* # of copiable lines in ptrn */
+	char	*s, *ret;
+	int	context = 0;
+
+	while (p_end >= 0) {
+		if (p_end == p_efake)
+			p_end = p_bfake;	/* don't free twice */
+		else
+			free(p_line[p_end]);
+		p_end--;
 	}
-	p_context = 100;
-	p_hunk_beg = p_input_line + 1;
-	while (p_end < p_max) {
-	    line_beginning = ftell(pfp);
-	    ret = pgets(buf, sizeof buf, pfp);
-	    p_input_line++;
-	    if (ret == Nullch) {
-		if (p_max - p_end < 4)
-		    Strcpy(buf, "  \n");  /* assume blank lines got chopped */
-		else {
-		    if (repl_beginning && repl_could_be_missing) {
-			repl_missing = TRUE;
-			goto hunk_done;
-		    }
-		    fatal1("Unexpected end of file in patch.\n");
+	p_efake = -1;
+
+	p_max = hunkmax;	/* gets reduced when --- found */
+	if (diff_type == CONTEXT_DIFF || diff_type == NEW_CONTEXT_DIFF) {
+		line_beginning = ftell(pfp);
+		repl_beginning = 0;
+		fillcnt = 0;
+		ptrn_spaces_eaten = false;
+		repl_could_be_missing = true;
+		repl_missing = false;
+		repl_backtrack_position = 0;
+		ptrn_copiable = 0;
+
+		ret = pgets(buf, sizeof buf, pfp);
+		p_input_line++;
+		if (ret == NULL || strnNE(buf, "********", 8)) {
+			next_intuit_at(line_beginning, p_input_line);
+			return false;
+		}
+		p_context = 100;
+		p_hunk_beg = p_input_line + 1;
+		while (p_end < p_max) {
+			line_beginning = ftell(pfp);
+			ret = pgets(buf, sizeof buf, pfp);
+			p_input_line++;
+			if (ret == NULL) {
+				if (p_max - p_end < 4) {
+					/* assume blank lines got chopped */
+					strlcpy(buf, "  \n", sizeof buf);
+				} else {
+					if (repl_beginning && repl_could_be_missing) {
+						repl_missing = true;
+						goto hunk_done;
+					}
+					fatal("unexpected end of file in patch\n");
+				}
+			}
+			p_end++;
+			if (p_end >= hunkmax)
+				fatal("Internal error: hunk larger than hunk "
+				    "buffer size");
+			p_char[p_end] = *buf;
+			p_line[p_end] = NULL;
+			switch (*buf) {
+			case '*':
+				if (strnEQ(buf, "********", 8)) {
+					if (repl_beginning && repl_could_be_missing) {
+						repl_missing = true;
+						goto hunk_done;
+					} else
+						fatal("unexpected end of hunk "
+						    "at line %ld\n",
+						    p_input_line);
+				}
+				if (p_end != 0) {
+					if (repl_beginning && repl_could_be_missing) {
+						repl_missing = true;
+						goto hunk_done;
+					}
+					fatal("unexpected *** at line %ld: %s",
+					    p_input_line, buf);
+				}
+				context = 0;
+				p_line[p_end] = savestr(buf);
+				if (out_of_mem) {
+					p_end--;
+					return false;
+				}
+				for (s = buf; *s && !isdigit(*s); s++)
+					;
+				if (!*s)
+					malformed();
+				if (strnEQ(s, "0,0", 3))
+					memmove(s, s + 2, strlen(s + 2) + 1);
+				p_first = (LINENUM) atol(s);
+				while (isdigit(*s))
+					s++;
+				if (*s == ',') {
+					for (; *s && !isdigit(*s); s++)
+						;
+					if (!*s)
+						malformed();
+					p_ptrn_lines = ((LINENUM) atol(s)) - p_first + 1;
+				} else if (p_first)
+					p_ptrn_lines = 1;
+				else {
+					p_ptrn_lines = 0;
+					p_first = 1;
+				}
+
+				/* we need this much at least */
+				p_max = p_ptrn_lines + 6;
+				while (p_max >= hunkmax)
+					grow_hunkmax();
+				p_max = hunkmax;
+				break;
+			case '-':
+				if (buf[1] == '-') {
+					if (repl_beginning ||
+					    (p_end != p_ptrn_lines + 1 +
+					    (p_char[p_end - 1] == '\n'))) {
+						if (p_end == 1) {
+							/*
+							 * `old' lines were omitted;
+							 * set up to fill them in
+							 * from 'new' context lines.
+							 */
+							p_end = p_ptrn_lines + 1;
+							fillsrc = p_end + 1;
+							filldst = 1;
+							fillcnt = p_ptrn_lines;
+						} else {
+							if (repl_beginning) {
+								if (repl_could_be_missing) {
+									repl_missing = true;
+									goto hunk_done;
+								}
+								fatal("duplicate \"---\" at line %ld--check line numbers at line %ld\n",
+								    p_input_line, p_hunk_beg + repl_beginning);
+							} else {
+								fatal("%s \"---\" at line %ld--check line numbers at line %ld\n",
+								    (p_end <= p_ptrn_lines
+								    ? "Premature"
+								    : "Overdue"),
+								    p_input_line, p_hunk_beg);
+							}
+						}
+					}
+					repl_beginning = p_end;
+					repl_backtrack_position = ftell(pfp);
+					repl_patch_line = p_input_line;
+					p_line[p_end] = savestr(buf);
+					if (out_of_mem) {
+						p_end--;
+						return false;
+					}
+					p_char[p_end] = '=';
+					for (s = buf; *s && !isdigit(*s); s++)
+						;
+					if (!*s)
+						malformed();
+					p_newfirst = (LINENUM) atol(s);
+					while (isdigit(*s))
+						s++;
+					if (*s == ',') {
+						for (; *s && !isdigit(*s); s++)
+							;
+						if (!*s)
+							malformed();
+						p_repl_lines = ((LINENUM) atol(s)) -
+						    p_newfirst + 1;
+					} else if (p_newfirst)
+						p_repl_lines = 1;
+					else {
+						p_repl_lines = 0;
+						p_newfirst = 1;
+					}
+					p_max = p_repl_lines + p_end;
+					if (p_max > MAXHUNKSIZE)
+						fatal("hunk too large (%ld lines) at line %ld: %s",
+						    p_max, p_input_line, buf);
+					while (p_max >= hunkmax)
+						grow_hunkmax();
+					if (p_repl_lines != ptrn_copiable &&
+					    (p_context != 0 || p_repl_lines != 1))
+						repl_could_be_missing = false;
+					break;
+				}
+				goto change_line;
+			case '+':
+			case '!':
+				repl_could_be_missing = false;
+		change_line:
+				if (buf[1] == '\n' && canonicalize)
+					strlcpy(buf + 1, " \n", sizeof buf - 1);
+				if (!isspace(buf[1]) && buf[1] != '>' &&
+				    buf[1] != '<' &&
+				    repl_beginning && repl_could_be_missing) {
+					repl_missing = true;
+					goto hunk_done;
+				}
+				if (context >= 0) {
+					if (context < p_context)
+						p_context = context;
+					context = -1000;
+				}
+				p_line[p_end] = savestr(buf + 2);
+				if (out_of_mem) {
+					p_end--;
+					return false;
+				}
+				if (p_end == p_ptrn_lines) {
+					if (remove_special_line()) {
+						int	len;
+
+						len = strlen(p_line[p_end]) - 1;
+						(p_line[p_end])[len] = 0;
+					}
+				}
+				break;
+			case '\t':
+			case '\n':	/* assume the 2 spaces got eaten */
+				if (repl_beginning && repl_could_be_missing &&
+				    (!ptrn_spaces_eaten ||
+				    diff_type == NEW_CONTEXT_DIFF)) {
+					repl_missing = true;
+					goto hunk_done;
+				}
+				p_line[p_end] = savestr(buf);
+				if (out_of_mem) {
+					p_end--;
+					return false;
+				}
+				if (p_end != p_ptrn_lines + 1) {
+					ptrn_spaces_eaten |= (repl_beginning != 0);
+					context++;
+					if (!repl_beginning)
+						ptrn_copiable++;
+					p_char[p_end] = ' ';
+				}
+				break;
+			case ' ':
+				if (!isspace(buf[1]) &&
+				    repl_beginning && repl_could_be_missing) {
+					repl_missing = true;
+					goto hunk_done;
+				}
+				context++;
+				if (!repl_beginning)
+					ptrn_copiable++;
+				p_line[p_end] = savestr(buf + 2);
+				if (out_of_mem) {
+					p_end--;
+					return false;
+				}
+				break;
+			default:
+				if (repl_beginning && repl_could_be_missing) {
+					repl_missing = true;
+					goto hunk_done;
+				}
+				malformed();
+			}
+			/* set up p_len for strncmp() so we don't have to */
+			/* assume null termination */
+			if (p_line[p_end])
+				p_len[p_end] = strlen(p_line[p_end]);
+			else
+				p_len[p_end] = 0;
 		}
-	    }
-	    p_end++;
-	    assert(p_end < hunkmax);
-	    p_char[p_end] = *buf;
-	    p_line[p_end] = Nullch;
-	    switch (*buf) {
-	    case '*':
-		if (strnEQ(buf, "********", 8)) {
-		    if (repl_beginning && repl_could_be_missing) {
-			repl_missing = TRUE;
-			goto hunk_done;
-		    }
-		    else
-			fatal2("Unexpected end of hunk at line %ld.\n",
-			    p_input_line);
+
+hunk_done:
+		if (p_end >= 0 && !repl_beginning)
+			fatal("no --- found in patch at line %ld\n", pch_hunk_beg());
+
+		if (repl_missing) {
+
+			/* reset state back to just after --- */
+			p_input_line = repl_patch_line;
+			for (p_end--; p_end > repl_beginning; p_end--)
+				free(p_line[p_end]);
+			fseek(pfp, repl_backtrack_position, SEEK_SET);
+
+			/* redundant 'new' context lines were omitted - set */
+			/* up to fill them in from the old file context */
+			if (!p_context && p_repl_lines == 1) {
+				p_repl_lines = 0;
+				p_max--;
+			}
+			fillsrc = 1;
+			filldst = repl_beginning + 1;
+			fillcnt = p_repl_lines;
+			p_end = p_max;
+		} else if (!p_context && fillcnt == 1) {
+			/* the first hunk was a null hunk with no context */
+			/* and we were expecting one line -- fix it up. */
+			while (filldst < p_end) {
+				p_line[filldst] = p_line[filldst + 1];
+				p_char[filldst] = p_char[filldst + 1];
+				p_len[filldst] = p_len[filldst + 1];
+				filldst++;
+			}
+#if 0
+			repl_beginning--;	/* this doesn't need to be fixed */
+#endif
+			p_end--;
+			p_first++;	/* do append rather than insert */
+			fillcnt = 0;
+			p_ptrn_lines = 0;
 		}
-		if (p_end != 0) {
-		    if (repl_beginning && repl_could_be_missing) {
-			repl_missing = TRUE;
-			goto hunk_done;
-		    }
-		    fatal3("Unexpected *** at line %ld: %s", p_input_line, buf);
+		if (diff_type == CONTEXT_DIFF &&
+		    (fillcnt || (p_first > 1 && ptrn_copiable > 2 * p_context))) {
+			if (verbose)
+				say("%s\n%s\n%s\n",
+				    "(Fascinating--this is really a new-style context diff but without",
+				    "the telltale extra asterisks on the *** line that usually indicate",
+				    "the new style...)");
+			diff_type = NEW_CONTEXT_DIFF;
 		}
-		context = 0;
-		p_line[p_end] = savestr(buf);
-		if (out_of_mem) {
-		    p_end--;
-		    return FALSE;
+		/* if there were omitted context lines, fill them in now */
+		if (fillcnt) {
+			p_bfake = filldst;	/* remember where not to free() */
+			p_efake = filldst + fillcnt - 1;
+			while (fillcnt-- > 0) {
+				while (fillsrc <= p_end && p_char[fillsrc] != ' ')
+					fillsrc++;
+				if (fillsrc > p_end)
+					fatal("replacement text or line numbers mangled in hunk at line %ld\n",
+					    p_hunk_beg);
+				p_line[filldst] = p_line[fillsrc];
+				p_char[filldst] = p_char[fillsrc];
+				p_len[filldst] = p_len[fillsrc];
+				fillsrc++;
+				filldst++;
+			}
+			while (fillsrc <= p_end && fillsrc != repl_beginning &&
+			    p_char[fillsrc] != ' ')
+				fillsrc++;
+#ifdef DEBUGGING
+			if (debug & 64)
+				printf("fillsrc %ld, filldst %ld, rb %ld, e+1 %ld\n",
+				fillsrc, filldst, repl_beginning, p_end + 1);
+#endif
+			if (fillsrc != p_end + 1 && fillsrc != repl_beginning)
+				malformed();
+			if (filldst != p_end + 1 && filldst != repl_beginning)
+				malformed();
+		}
+		if (p_line[p_end] != NULL) {
+			if (remove_special_line()) {
+				p_len[p_end] -= 1;
+				(p_line[p_end])[p_len[p_end]] = 0;
+			}
 		}
-		for (s=buf; *s && !isdigit(*s); s++) ;
+	} else if (diff_type == UNI_DIFF) {
+		long	line_beginning = ftell(pfp); /* file pos of the current line */
+		LINENUM	fillsrc;	/* index of old lines */
+		LINENUM	filldst;	/* index of new lines */
+		char	ch;
+
+		ret = pgets(buf, sizeof buf, pfp);
+		p_input_line++;
+		if (ret == NULL || strnNE(buf, "@@ -", 4)) {
+			next_intuit_at(line_beginning, p_input_line);
+			return false;
+		}
+		s = buf + 4;
 		if (!*s)
-		    goto malformed;
+			malformed();
 		p_first = (LINENUM) atol(s);
-		while (isdigit(*s)) s++;
+		while (isdigit(*s))
+			s++;
+		if (*s == ',') {
+			p_ptrn_lines = (LINENUM) atol(++s);
+			while (isdigit(*s))
+				s++;
+		} else
+			p_ptrn_lines = 1;
+		if (*s == ' ')
+			s++;
+		if (*s != '+' || !*++s)
+			malformed();
+		p_newfirst = (LINENUM) atol(s);
+		while (isdigit(*s))
+			s++;
 		if (*s == ',') {
-		    for (; *s && !isdigit(*s); s++) ;
-		    if (!*s)
-			goto malformed;
-		    p_ptrn_lines = ((LINENUM)atol(s)) - p_first + 1;
+			p_repl_lines = (LINENUM) atol(++s);
+			while (isdigit(*s))
+				s++;
+		} else
+			p_repl_lines = 1;
+		if (*s == ' ')
+			s++;
+		if (*s != '@')
+			malformed();
+		if (!p_ptrn_lines)
+			p_first++;	/* do append rather than insert */
+		p_max = p_ptrn_lines + p_repl_lines + 1;
+		while (p_max >= hunkmax)
+			grow_hunkmax();
+		fillsrc = 1;
+		filldst = fillsrc + p_ptrn_lines;
+		p_end = filldst + p_repl_lines;
+		snprintf(buf, sizeof buf, "*** %ld,%ld ****\n", p_first,
+		    p_first + p_ptrn_lines - 1);
+		p_line[0] = savestr(buf);
+		if (out_of_mem) {
+			p_end = -1;
+			return false;
 		}
-		else if (p_first)
-		    p_ptrn_lines = 1;
-		else {
-		    p_ptrn_lines = 0;
-		    p_first = 1;
+		p_char[0] = '*';
+		snprintf(buf, sizeof buf, "--- %ld,%ld ----\n", p_newfirst,
+		    p_newfirst + p_repl_lines - 1);
+		p_line[filldst] = savestr(buf);
+		if (out_of_mem) {
+			p_end = 0;
+			return false;
 		}
-		p_max = p_ptrn_lines + 6;	/* we need this much at least */
-		while (p_max >= hunkmax)
-		    grow_hunkmax();
-		p_max = hunkmax;
-		break;
-	    case '-':
-		if (buf[1] == '-') {
-		    if (repl_beginning ||
-			(p_end != p_ptrn_lines + 1 + (p_char[p_end-1] == '\n')))
-		    {
-			if (p_end == 1) {
-			    /* `old' lines were omitted - set up to fill */
-			    /* them in from 'new' context lines. */
-			    p_end = p_ptrn_lines + 1;
-			    fillsrc = p_end + 1;
-			    filldst = 1;
-			    fillcnt = p_ptrn_lines;
+		p_char[filldst++] = '=';
+		p_context = 100;
+		context = 0;
+		p_hunk_beg = p_input_line + 1;
+		while (fillsrc <= p_ptrn_lines || filldst <= p_end) {
+			line_beginning = ftell(pfp);
+			ret = pgets(buf, sizeof buf, pfp);
+			p_input_line++;
+			if (ret == NULL) {
+				if (p_max - filldst < 3) {
+					/* assume blank lines got chopped */
+					strlcpy(buf, " \n", sizeof buf);
+				} else {
+					fatal("unexpected end of file in patch\n");
+				}
 			}
-			else {
-			    if (repl_beginning) {
-				if (repl_could_be_missing){
-				    repl_missing = TRUE;
-				    goto hunk_done;
+			if (*buf == '\t' || *buf == '\n') {
+				ch = ' ';	/* assume the space got eaten */
+				s = savestr(buf);
+			} else {
+				ch = *buf;
+				s = savestr(buf + 1);
+			}
+			if (out_of_mem) {
+				while (--filldst > p_ptrn_lines)
+					free(p_line[filldst]);
+				p_end = fillsrc - 1;
+				return false;
+			}
+			switch (ch) {
+			case '-':
+				if (fillsrc > p_ptrn_lines) {
+					free(s);
+					p_end = filldst - 1;
+					malformed();
+				}
+				p_char[fillsrc] = ch;
+				p_line[fillsrc] = s;
+				p_len[fillsrc++] = strlen(s);
+				if (fillsrc > p_ptrn_lines) {
+					if (remove_special_line()) {
+						p_len[fillsrc - 1] -= 1;
+						s[p_len[fillsrc - 1]] = 0;
+					}
+				}
+				break;
+			case '=':
+				ch = ' ';
+				/* FALL THROUGH */
+			case ' ':
+				if (fillsrc > p_ptrn_lines) {
+					free(s);
+					while (--filldst > p_ptrn_lines)
+						free(p_line[filldst]);
+					p_end = fillsrc - 1;
+					malformed();
 				}
-				fatal3(
-"Duplicate \"---\" at line %ld--check line numbers at line %ld.\n",
-				    p_input_line, p_hunk_beg + repl_beginning);
-			    }
-			    else {
-				fatal4(
-"%s \"---\" at line %ld--check line numbers at line %ld.\n",
-				    (p_end <= p_ptrn_lines
-					? "Premature"
-					: "Overdue" ),
-				    p_input_line, p_hunk_beg);
-			    }
+				context++;
+				p_char[fillsrc] = ch;
+				p_line[fillsrc] = s;
+				p_len[fillsrc++] = strlen(s);
+				s = savestr(s);
+				if (out_of_mem) {
+					while (--filldst > p_ptrn_lines)
+						free(p_line[filldst]);
+					p_end = fillsrc - 1;
+					return false;
+				}
+				if (fillsrc > p_ptrn_lines) {
+					if (remove_special_line()) {
+						p_len[fillsrc - 1] -= 1;
+						s[p_len[fillsrc - 1]] = 0;
+					}
+				}
+				/* FALL THROUGH */
+			case '+':
+				if (filldst > p_end) {
+					free(s);
+					while (--filldst > p_ptrn_lines)
+						free(p_line[filldst]);
+					p_end = fillsrc - 1;
+					malformed();
+				}
+				p_char[filldst] = ch;
+				p_line[filldst] = s;
+				p_len[filldst++] = strlen(s);
+				if (fillsrc > p_ptrn_lines) {
+					if (remove_special_line()) {
+						p_len[filldst - 1] -= 1;
+						s[p_len[filldst - 1]] = 0;
+					}
+				}
+				break;
+			default:
+				p_end = filldst;
+				malformed();
 			}
-		    }
-		    repl_beginning = p_end;
-		    repl_backtrack_position = ftell(pfp);
-		    repl_patch_line = p_input_line;
-		    p_line[p_end] = savestr(buf);
-		    if (out_of_mem) {
-			p_end--;
-			return FALSE;
-		    }
-		    p_char[p_end] = '=';
-		    for (s=buf; *s && !isdigit(*s); s++) ;
-		    if (!*s)
-			goto malformed;
-		    p_newfirst = (LINENUM) atol(s);
-		    while (isdigit(*s)) s++;
-		    if (*s == ',') {
-			for (; *s && !isdigit(*s); s++) ;
-			if (!*s)
-			    goto malformed;
-			p_repl_lines = ((LINENUM)atol(s)) - p_newfirst + 1;
-		    }
-		    else if (p_newfirst)
-			p_repl_lines = 1;
-		    else {
-			p_repl_lines = 0;
-			p_newfirst = 1;
-		    }
-		    p_max = p_repl_lines + p_end;
-		    if (p_max > MAXHUNKSIZE)
-			fatal4("Hunk too large (%ld lines) at line %ld: %s",
-			      p_max, p_input_line, buf);
-		    while (p_max >= hunkmax)
-			grow_hunkmax();
-		    if (p_repl_lines != ptrn_copiable)
-			repl_could_be_missing = FALSE;
-		    break;
-		}
-		goto change_line;
-	    case '+':  case '!':
-		repl_could_be_missing = FALSE;
-	      change_line:
-		if (!isspace(buf[1]) && buf[1] != '>' && buf[1] != '<' &&
-		  repl_beginning && repl_could_be_missing) {
-		    repl_missing = TRUE;
-		    goto hunk_done;
-		}
-		if (context > 0) {
-		    if (context < p_context)
-			p_context = context;
-		    context = -1000;
+			if (ch != ' ' && context > 0) {
+				if (context < p_context)
+					p_context = context;
+				context = -1000;
+			}
+		}		/* while */
+	} else {		/* normal diff--fake it up */
+		char	hunk_type;
+		int	i;
+		LINENUM	min, max;
+		long	line_beginning = ftell(pfp);
+
+		p_context = 0;
+		ret = pgets(buf, sizeof buf, pfp);
+		p_input_line++;
+		if (ret == NULL || !isdigit(*buf)) {
+			next_intuit_at(line_beginning, p_input_line);
+			return false;
 		}
-		p_line[p_end] = savestr(buf+2);
+		p_first = (LINENUM) atol(buf);
+		for (s = buf; isdigit(*s); s++)
+			;
+		if (*s == ',') {
+			p_ptrn_lines = (LINENUM) atol(++s) - p_first + 1;
+			while (isdigit(*s))
+				s++;
+		} else
+			p_ptrn_lines = (*s != 'a');
+		hunk_type = *s;
+		if (hunk_type == 'a')
+			p_first++;	/* do append rather than insert */
+		min = (LINENUM) atol(++s);
+		for (; isdigit(*s); s++)
+			;
+		if (*s == ',')
+			max = (LINENUM) atol(++s);
+		else
+			max = min;
+		if (hunk_type == 'd')
+			min++;
+		p_end = p_ptrn_lines + 1 + max - min + 1;
+		if (p_end > MAXHUNKSIZE)
+			fatal("hunk too large (%ld lines) at line %ld: %s",
+			    p_end, p_input_line, buf);
+		while (p_end >= hunkmax)
+			grow_hunkmax();
+		p_newfirst = min;
+		p_repl_lines = max - min + 1;
+		snprintf(buf, sizeof buf, "*** %ld,%ld\n", p_first,
+		    p_first + p_ptrn_lines - 1);
+		p_line[0] = savestr(buf);
 		if (out_of_mem) {
-		    p_end--;
-		    return FALSE;
-		}
-		break;
-	    case '\t': case '\n':	/* assume the 2 spaces got eaten */
-		if (repl_beginning && repl_could_be_missing &&
-		  (!ptrn_spaces_eaten || diff_type == NEW_CONTEXT_DIFF) ) {
-		    repl_missing = TRUE;
-		    goto hunk_done;
+			p_end = -1;
+			return false;
 		}
-		p_line[p_end] = savestr(buf);
-		if (out_of_mem) {
-		    p_end--;
-		    return FALSE;
+		p_char[0] = '*';
+		for (i = 1; i <= p_ptrn_lines; i++) {
+			ret = pgets(buf, sizeof buf, pfp);
+			p_input_line++;
+			if (ret == NULL)
+				fatal("unexpected end of file in patch at line %ld\n",
+				    p_input_line);
+			if (*buf != '<')
+				fatal("< expected at line %ld of patch\n",
+				    p_input_line);
+			p_line[i] = savestr(buf + 2);
+			if (out_of_mem) {
+				p_end = i - 1;
+				return false;
+			}
+			p_len[i] = strlen(p_line[i]);
+			p_char[i] = '-';
 		}
-		if (p_end != p_ptrn_lines + 1) {
-		    ptrn_spaces_eaten |= (repl_beginning != 0);
-		    context++;
-		    if (!repl_beginning)
-			ptrn_copiable++;
-		    p_char[p_end] = ' ';
+
+		if (remove_special_line()) {
+			p_len[i - 1] -= 1;
+			(p_line[i - 1])[p_len[i - 1]] = 0;
 		}
-		break;
-	    case ' ':
-		if (!isspace(buf[1]) &&
-		  repl_beginning && repl_could_be_missing) {
-		    repl_missing = TRUE;
-		    goto hunk_done;
+		if (hunk_type == 'c') {
+			ret = pgets(buf, sizeof buf, pfp);
+			p_input_line++;
+			if (ret == NULL)
+				fatal("unexpected end of file in patch at line %ld\n",
+				    p_input_line);
+			if (*buf != '-')
+				fatal("--- expected at line %ld of patch\n",
+				    p_input_line);
 		}
-		context++;
-		if (!repl_beginning)
-		    ptrn_copiable++;
-		p_line[p_end] = savestr(buf+2);
+		snprintf(buf, sizeof(buf), "--- %ld,%ld\n", min, max);
+		p_line[i] = savestr(buf);
 		if (out_of_mem) {
-		    p_end--;
-		    return FALSE;
+			p_end = i - 1;
+			return false;
 		}
-		break;
-	    default:
-		if (repl_beginning && repl_could_be_missing) {
-		    repl_missing = TRUE;
-		    goto hunk_done;
+		p_char[i] = '=';
+		for (i++; i <= p_end; i++) {
+			ret = pgets(buf, sizeof buf, pfp);
+			p_input_line++;
+			if (ret == NULL)
+				fatal("unexpected end of file in patch at line %ld\n",
+				    p_input_line);
+			if (*buf != '>')
+				fatal("> expected at line %ld of patch\n",
+				    p_input_line);
+			p_line[i] = savestr(buf + 2);
+			if (out_of_mem) {
+				p_end = i - 1;
+				return false;
+			}
+			p_len[i] = strlen(p_line[i]);
+			p_char[i] = '+';
 		}
-		goto malformed;
-	    }
-	    /* set up p_len for strncmp() so we don't have to */
-	    /* assume null termination */
-	    if (p_line[p_end])
-		p_len[p_end] = strlen(p_line[p_end]);
-	    else
-		p_len[p_end] = 0;
-	}
-	
-    hunk_done:
-	if (p_end >=0 && !repl_beginning)
-	    fatal2("No --- found in patch at line %ld\n", pch_hunk_beg());
-
-	if (repl_missing) {
-	    
-	    /* reset state back to just after --- */
-	    p_input_line = repl_patch_line;
-	    for (p_end--; p_end > repl_beginning; p_end--)
-		free(p_line[p_end]);
-	    Fseek(pfp, repl_backtrack_position, 0);
-	    
-	    /* redundant 'new' context lines were omitted - set */
-	    /* up to fill them in from the old file context */
-	    fillsrc = 1;
-	    filldst = repl_beginning+1;
-	    fillcnt = p_repl_lines;
-	    p_end = p_max;
-	}
 
-	if (diff_type == CONTEXT_DIFF &&
-	  (fillcnt || (p_first > 1 && ptrn_copiable > 2*p_context)) ) {
-	    if (verbose)
-		say1("\
-(Fascinating--this is really a new-style context diff but without the telltale\n\
-extra asterisks on the *** line that usually indicate the new style...)\n");
-	    diff_type = NEW_CONTEXT_DIFF;
+		if (remove_special_line()) {
+			p_len[i - 1] -= 1;
+			(p_line[i - 1])[p_len[i - 1]] = 0;
+		}
 	}
-	
-	/* if there were omitted context lines, fill them in now */
-	if (fillcnt) {
-	    p_bfake = filldst;		/* remember where not to free() */
-	    p_efake = filldst + fillcnt - 1;
-	    while (fillcnt-- > 0) {
-		while (fillsrc <= p_end && p_char[fillsrc] != ' ')
-		    fillsrc++;
-		if (fillsrc > p_end)
-		    fatal2("Replacement text or line numbers mangled in hunk at line %ld\n",
-			p_hunk_beg);
-		p_line[filldst] = p_line[fillsrc];
-		p_char[filldst] = p_char[fillsrc];
-		p_len[filldst] = p_len[fillsrc];
-		fillsrc++; filldst++;
-	    }
-	    while (fillsrc <= p_end && fillsrc != repl_beginning &&
-	      p_char[fillsrc] != ' ')
-		fillsrc++;
+	if (reverse)		/* backwards patch? */
+		if (!pch_swap())
+			say("Not enough memory to swap next hunk!\n");
 #ifdef DEBUGGING
-	    if (debug & 64)
-		printf("fillsrc %ld, filldst %ld, rb %ld, e+1 %ld\n",
-		    fillsrc,filldst,repl_beginning,p_end+1);
-#endif
-	    assert(fillsrc==p_end+1 || fillsrc==repl_beginning);
-	    assert(filldst==p_end+1 || filldst==repl_beginning);
-	}
-    }
-    else {				/* normal diff--fake it up */
-	char hunk_type;
-	Reg3 int i;
-	LINENUM min, max;
-	long line_beginning = ftell(pfp);
-
-	p_context = 0;
-	ret = pgets(buf, sizeof buf, pfp);
-	p_input_line++;
-	if (ret == Nullch || !isdigit(*buf)) {
-	    next_intuit_at(line_beginning,p_input_line);
-	    return FALSE;
+	if (debug & 2) {
+		int	i;
+		char	special;
+
+		for (i = 0; i <= p_end; i++) {
+			if (i == p_ptrn_lines)
+				special = '^';
+			else
+				special = ' ';
+			fprintf(stderr, "%3d %c %c %s", i, p_char[i],
+			    special, p_line[i]);
+			fflush(stderr);
+		}
 	}
-	p_first = (LINENUM)atol(buf);
-	for (s=buf; isdigit(*s); s++) ;
-	if (*s == ',') {
-	    p_ptrn_lines = (LINENUM)atol(++s) - p_first + 1;
-	    while (isdigit(*s)) s++;
+#endif
+	if (p_end + 1 < hunkmax)/* paranoia reigns supreme... */
+		p_char[p_end + 1] = '^';	/* add a stopper for apply_hunk */
+	return true;
+}
+
+/*
+ * Input a line from the patch file, worrying about indentation.
+ */
+static char *
+pgets(char *bf, int sz, FILE *fp)
+{
+	char	*s, *ret = fgets(bf, sz, fp);
+	int	indent = 0;
+
+	if (p_indent && ret != NULL) {
+		for (s = buf;
+		    indent < p_indent && (*s == ' ' || *s == '\t' || *s == 'X');
+		    s++) {
+			if (*s == '\t')
+				indent += 8 - (indent % 7);
+			else
+				indent++;
+		}
+		if (buf != s && strlcpy(buf, s, sizeof(buf)) >= sizeof(buf))
+			fatal("buffer too small in pgets()\n");
 	}
-	else
-	    p_ptrn_lines = (*s != 'a');
-	hunk_type = *s;
-	if (hunk_type == 'a')
-	    p_first++;			/* do append rather than insert */
-	min = (LINENUM)atol(++s);
-	for (; isdigit(*s); s++) ;
-	if (*s == ',')
-	    max = (LINENUM)atol(++s);
-	else
-	    max = min;
-	if (hunk_type == 'd')
-	    min++;
-	p_end = p_ptrn_lines + 1 + max - min + 1;
-	if (p_end > MAXHUNKSIZE)
-	    fatal4("Hunk too large (%ld lines) at line %ld: %s",
-		  p_end, p_input_line, buf);
-	while (p_end >= hunkmax)
-	    grow_hunkmax();
-	p_newfirst = min;
-	p_repl_lines = max - min + 1;
-	Sprintf(buf, "*** %ld,%ld\n", p_first, p_first + p_ptrn_lines - 1);
-	p_line[0] = savestr(buf);
-	if (out_of_mem) {
-	    p_end = -1;
-	    return FALSE;
+	return ret;
+}
+
+/*
+ * Reverse the old and new portions of the current hunk.
+ */
+bool
+pch_swap(void)
+{
+	char	**tp_line;	/* the text of the hunk */
+	short	*tp_len;	/* length of each line */
+	char	*tp_char;	/* +, -, and ! */
+	LINENUM	i;
+	LINENUM	n;
+	bool	blankline = false;
+	char	*s;
+
+	i = p_first;
+	p_first = p_newfirst;
+	p_newfirst = i;
+
+	/* make a scratch copy */
+
+	tp_line = p_line;
+	tp_len = p_len;
+	tp_char = p_char;
+	p_line = NULL;	/* force set_hunkmax to allocate again */
+	p_len = NULL;
+	p_char = NULL;
+	set_hunkmax();
+	if (p_line == NULL || p_len == NULL || p_char == NULL) {
+
+		free(p_line);
+		p_line = tp_line;
+		free(p_len);
+		p_len = tp_len;
+		free(p_char);
+		p_char = tp_char;
+		return false;	/* not enough memory to swap hunk! */
 	}
-	p_char[0] = '*';
-	for (i=1; i<=p_ptrn_lines; i++) {
-	    ret = pgets(buf, sizeof buf, pfp);
-	    p_input_line++;
-	    if (ret == Nullch)
-		fatal2("Unexpected end of file in patch at line %ld.\n",
-		  p_input_line);
-	    if (*buf != '<')
-		fatal2("< expected at line %ld of patch.\n", p_input_line);
-	    p_line[i] = savestr(buf+2);
-	    if (out_of_mem) {
-		p_end = i-1;
-		return FALSE;
-	    }
-	    p_len[i] = strlen(p_line[i]);
-	    p_char[i] = '-';
+	/* now turn the new into the old */
+
+	i = p_ptrn_lines + 1;
+	if (tp_char[i] == '\n') {	/* account for possible blank line */
+		blankline = true;
+		i++;
 	}
-	if (hunk_type == 'c') {
-	    ret = pgets(buf, sizeof buf, pfp);
-	    p_input_line++;
-	    if (ret == Nullch)
-		fatal2("Unexpected end of file in patch at line %ld.\n",
-		    p_input_line);
-	    if (*buf != '-')
-		fatal2("--- expected at line %ld of patch.\n", p_input_line);
+	if (p_efake >= 0) {	/* fix non-freeable ptr range */
+		if (p_efake <= i)
+			n = p_end - i + 1;
+		else
+			n = -i;
+		p_efake += n;
+		p_bfake += n;
 	}
-	Sprintf(buf, "--- %ld,%ld\n", min, max);
-	p_line[i] = savestr(buf);
-	if (out_of_mem) {
-	    p_end = i-1;
-	    return FALSE;
+	for (n = 0; i <= p_end; i++, n++) {
+		p_line[n] = tp_line[i];
+		p_char[n] = tp_char[i];
+		if (p_char[n] == '+')
+			p_char[n] = '-';
+		p_len[n] = tp_len[i];
 	}
-	p_char[i] = '=';
-	for (i++; i<=p_end; i++) {
-	    ret = pgets(buf, sizeof buf, pfp);
-	    p_input_line++;
-	    if (ret == Nullch)
-		fatal2("Unexpected end of file in patch at line %ld.\n",
-		    p_input_line);
-	    if (*buf != '>')
-		fatal2("> expected at line %ld of patch.\n", p_input_line);
-	    p_line[i] = savestr(buf+2);
-	    if (out_of_mem) {
-		p_end = i-1;
-		return FALSE;
-	    }
-	    p_len[i] = strlen(p_line[i]);
-	    p_char[i] = '+';
+	if (blankline) {
+		i = p_ptrn_lines + 1;
+		p_line[n] = tp_line[i];
+		p_char[n] = tp_char[i];
+		p_len[n] = tp_len[i];
+		n++;
 	}
-    }
-    if (reverse)			/* backwards patch? */
-	if (!pch_swap())
-	    say1("Not enough memory to swap next hunk!\n");
-#ifdef DEBUGGING
-    if (debug & 2) {
-	int i;
-	char special;
-
-	for (i=0; i <= p_end; i++) {
-	    if (i == p_ptrn_lines)
-		special = '^';
-	    else
-		special = ' ';
-	    fprintf(stderr, "%3d %c %c %s", i, p_char[i], special, p_line[i]);
-	    Fflush(stderr);
+	if (p_char[0] != '=')
+		fatal("Malformed patch at line %ld: expected '=' found '%c'\n",
+		    p_input_line, p_char[0]);
+	p_char[0] = '*';
+	for (s = p_line[0]; *s; s++)
+		if (*s == '-')
+			*s = '*';
+
+	/* now turn the old into the new */
+
+	if (p_char[0] != '*')
+		fatal("Malformed patch at line %ld: expected '*' found '%c'\n",
+		    p_input_line, p_char[0]);
+	tp_char[0] = '=';
+	for (s = tp_line[0]; *s; s++)
+		if (*s == '*')
+			*s = '-';
+	for (i = 0; n <= p_end; i++, n++) {
+		p_line[n] = tp_line[i];
+		p_char[n] = tp_char[i];
+		if (p_char[n] == '-')
+			p_char[n] = '+';
+		p_len[n] = tp_len[i];
 	}
-    }
-#endif
-    if (p_end+1 < hunkmax)	/* paranoia reigns supreme... */
-	p_char[p_end+1] = '^';  /* add a stopper for apply_hunk */
-    return TRUE;
-
-malformed:
-    fatal3("Malformed patch at line %ld: %s", p_input_line, buf);
-		/* about as informative as "Syntax error" in C */
-    return FALSE;	/* for lint */
-}
 
-/* Input a line from the patch file, worrying about indentation. */
+	if (i != p_ptrn_lines + 1)
+		fatal("Malformed patch at line %ld: expected %ld lines, "
+		    "got %ld\n",
+		    p_input_line, p_ptrn_lines + 1, i);
 
-char *
-pgets(bf,sz,fp)
-char *bf;
-int sz;
-FILE *fp;
-{
-    char *ret = fgets(bf, sz, fp);
-    Reg1 char *s;
-    Reg2 int indent = 0;
-
-    if (p_indent && ret != Nullch) {
-	for (s=buf; indent < p_indent && (*s == ' ' || *s == '\t'); s++) {
-	    if (*s == '\t')
-		indent += 8 - (indent % 7);
-	    else
-		indent++;
-	}
-	if (buf != s)
-	    Strcpy(buf, s);
-    }
-    return ret;
-}
+	i = p_ptrn_lines;
+	p_ptrn_lines = p_repl_lines;
+	p_repl_lines = i;
 
-/* Reverse the old and new portions of the current hunk. */
+	free(tp_line);
+	free(tp_len);
+	free(tp_char);
 
-bool
-pch_swap()
-{
-    char **tp_line;		/* the text of the hunk */
-    short *tp_len;		/* length of each line */
-    char *tp_char;		/* +, -, and ! */
-    Reg1 LINENUM i;
-    Reg2 LINENUM n;
-    bool blankline = FALSE;
-    Reg3 char *s;
-
-    i = p_first;
-    p_first = p_newfirst;
-    p_newfirst = i;
-    
-    /* make a scratch copy */
-
-    tp_line = p_line;
-    tp_len = p_len;
-    tp_char = p_char;
-    p_line = Null(char**);	/* force set_hunkmax to allocate again */
-    p_len = Null(short*);
-    p_char = Nullch;
-    set_hunkmax();
-    if (p_line == Null(char**) || p_len == Null(short*) || p_char == Nullch) {
-#ifndef lint
-	if (p_line == Null(char**))
-	    free((char*)p_line);
-	p_line = tp_line;
-	if (p_len == Null(short*))
-	    free((char*)p_len);
-	p_len = tp_len;
-#endif
-	if (p_char == Nullch)
-	    free((char*)p_char);
-	p_char = tp_char;
-	return FALSE;		/* not enough memory to swap hunk! */
-    }
-
-    /* now turn the new into the old */
-
-    i = p_ptrn_lines + 1;
-    if (tp_char[i] == '\n') {		/* account for possible blank line */
-	blankline = TRUE;
-	i++;
-    }
-    if (p_efake >= 0) {			/* fix non-freeable ptr range */
-	n = p_end - i + 1;
-	if (p_efake > i)
-	    n = -n;
-	p_efake += n;
-	p_bfake += n;
-    }
-    for (n=0; i <= p_end; i++,n++) {
-	p_line[n] = tp_line[i];
-	p_char[n] = tp_char[i];
-	if (p_char[n] == '+')
-	    p_char[n] = '-';
-	p_len[n] = tp_len[i];
-    }
-    if (blankline) {
-	i = p_ptrn_lines + 1;
-	p_line[n] = tp_line[i];
-	p_char[n] = tp_char[i];
-	p_len[n] = tp_len[i];
-	n++;
-    }
-    assert(p_char[0] == '=');
-    p_char[0] = '*';
-    for (s=p_line[0]; *s; s++)
-	if (*s == '-')
-	    *s = '*';
-
-    /* now turn the old into the new */
-
-    assert(tp_char[0] == '*');
-    tp_char[0] = '=';
-    for (s=tp_line[0]; *s; s++)
-	if (*s == '*')
-	    *s = '-';
-    for (i=0; n <= p_end; i++,n++) {
-	p_line[n] = tp_line[i];
-	p_char[n] = tp_char[i];
-	if (p_char[n] == '-')
-	    p_char[n] = '+';
-	p_len[n] = tp_len[i];
-    }
-    assert(i == p_ptrn_lines + 1);
-    i = p_ptrn_lines;
-    p_ptrn_lines = p_repl_lines;
-    p_repl_lines = i;
-#ifndef lint
-    if (tp_line == Null(char**))
-	free((char*)tp_line);
-    if (tp_len == Null(short*))
-	free((char*)tp_len);
-#endif
-    if (tp_char == Nullch)
-	free((char*)tp_char);
-    return TRUE;
+	return true;
 }
 
-/* Return the specified line position in the old file of the old context. */
-
+/*
+ * Return the specified line position in the old file of the old context.
+ */
 LINENUM
-pch_first()
+pch_first(void)
 {
-    return p_first;
+	return p_first;
 }
 
-/* Return the number of lines of old context. */
-
+/*
+ * Return the number of lines of old context.
+ */
 LINENUM
-pch_ptrn_lines()
+pch_ptrn_lines(void)
 {
-    return p_ptrn_lines;
+	return p_ptrn_lines;
 }
 
-/* Return the probable line position in the new file of the first line. */
-
+/*
+ * Return the probable line position in the new file of the first line.
+ */
 LINENUM
-pch_newfirst()
+pch_newfirst(void)
 {
-    return p_newfirst;
+	return p_newfirst;
 }
 
-/* Return the number of lines in the replacement text including context. */
-
+/*
+ * Return the number of lines in the replacement text including context.
+ */
 LINENUM
-pch_repl_lines()
+pch_repl_lines(void)
 {
-    return p_repl_lines;
+	return p_repl_lines;
 }
 
-/* Return the number of lines in the whole hunk. */
-
+/*
+ * Return the number of lines in the whole hunk.
+ */
 LINENUM
-pch_end()
+pch_end(void)
 {
-    return p_end;
+	return p_end;
 }
 
-/* Return the number of context lines before the first changed line. */
-
+/*
+ * Return the number of context lines before the first changed line.
+ */
 LINENUM
-pch_context()
+pch_context(void)
 {
-    return p_context;
+	return p_context;
 }
 
-/* Return the length of a particular patch line. */
-
+/*
+ * Return the length of a particular patch line.
+ */
 short
-pch_line_len(line)
-LINENUM line;
+pch_line_len(LINENUM line)
 {
-    return p_len[line];
+	return p_len[line];
 }
 
-/* Return the control character (+, -, *, !, etc) for a patch line. */
-
+/*
+ * Return the control character (+, -, *, !, etc) for a patch line.
+ */
 char
-pch_char(line)
-LINENUM line;
+pch_char(LINENUM line)
 {
-    return p_char[line];
+	return p_char[line];
 }
 
-/* Return a pointer to a particular patch line. */
-
+/*
+ * Return a pointer to a particular patch line.
+ */
 char *
-pfetch(line)
-LINENUM line;
+pfetch(LINENUM line)
 {
-    return p_line[line];
+	return p_line[line];
 }
 
-/* Return where in the patch file this hunk began, for error messages. */
-
+/*
+ * Return where in the patch file this hunk began, for error messages.
+ */
 LINENUM
-pch_hunk_beg()
+pch_hunk_beg(void)
 {
-    return p_hunk_beg;
+	return p_hunk_beg;
 }
 
-/* Apply an ed script by feeding ed itself. */
-
+/*
+ * Apply an ed script by feeding ed itself.
+ */
 void
-do_ed_script()
+do_ed_script(void)
 {
-    Reg1 char *t;
-    Reg2 long beginning_of_this_line;
-    Reg3 bool this_line_is_command = FALSE;
-    Reg4 FILE *pipefp;
-    FILE *popen();
-
-    if (!skip_rest_of_patch) {
-	Unlink(TMPOUTNAME);
-	copy_file(filearg[0], TMPOUTNAME);
-	if (verbose)
-	    Sprintf(buf, "/bin/ed %s", TMPOUTNAME);
-	else
-	    Sprintf(buf, "/bin/ed - %s", TMPOUTNAME);
-	pipefp = popen(buf, "w");
-    }
-    for (;;) {
-	beginning_of_this_line = ftell(pfp);
-	if (pgets(buf, sizeof buf, pfp) == Nullch) {
-	    next_intuit_at(beginning_of_this_line,p_input_line);
-	    break;
+	char	*t;
+	long	beginning_of_this_line;
+	FILE	*pipefp;
+
+	pipefp = NULL;
+	if (!skip_rest_of_patch) {
+		if (copy_file(filearg[0], TMPOUTNAME) < 0) {
+			unlink(TMPOUTNAME);
+			fatal("can't create temp file %s", TMPOUTNAME);
+		}
+		snprintf(buf, sizeof buf, "%s%s%s", _PATH_ED,
+		    verbose ? " " : " -s ", TMPOUTNAME);
+		pipefp = popen(buf, "w");
+	}
+	for (;;) {
+		beginning_of_this_line = ftell(pfp);
+		if (pgets(buf, sizeof buf, pfp) == NULL) {
+			next_intuit_at(beginning_of_this_line, p_input_line);
+			break;
+		}
+		p_input_line++;
+		for (t = buf; isdigit(*t) || *t == ','; t++)
+			;
+		/* POSIX defines allowed commands as {a,c,d,i,s} */
+		if (isdigit(*buf) && (*t == 'a' || *t == 'c' || *t == 'd' ||
+		    *t == 'i' || *t == 's')) {
+			if (pipefp != NULL)
+				fputs(buf, pipefp);
+			if (*t != 'd') {
+				while (pgets(buf, sizeof buf, pfp) != NULL) {
+					p_input_line++;
+					if (pipefp != NULL)
+						fputs(buf, pipefp);
+					if (strEQ(buf, ".\n"))
+						break;
+				}
+			}
+		} else {
+			next_intuit_at(beginning_of_this_line, p_input_line);
+			break;
+		}
+	}
+	if (pipefp == NULL)
+		return;
+	fprintf(pipefp, "w\n");
+	fprintf(pipefp, "q\n");
+	fflush(pipefp);
+	pclose(pipefp);
+	ignore_signals();
+	if (!check_only) {
+		if (move_file(TMPOUTNAME, outname) < 0) {
+			toutkeep = true;
+			chmod(TMPOUTNAME, filemode);
+		} else
+			chmod(outname, filemode);
 	}
-	p_input_line++;
-	for (t=buf; isdigit(*t) || *t == ','; t++) ;
-	this_line_is_command = (isdigit(*buf) &&
-	  (*t == 'd' || *t == 'c' || *t == 'a') );
-	if (this_line_is_command) {
-	    if (!skip_rest_of_patch)
-		fputs(buf, pipefp);
-	    if (*t != 'd') {
-		while (pgets(buf, sizeof buf, pfp) != Nullch) {
-		    p_input_line++;
-		    if (!skip_rest_of_patch)
-			fputs(buf, pipefp);
-		    if (strEQ(buf, ".\n"))
+	set_signals(1);
+}
+
+/*
+ * Choose the name of the file to be patched based on POSIX rules.
+ * NOTE: the POSIX rules are amazingly stupid and we only follow them
+ *       if the user specified --posix or set POSIXLY_CORRECT.
+ */
+static char *
+posix_name(const struct file_name *names, bool assume_exists)
+{
+	char *path = NULL;
+	int i;
+
+	/*
+	 * POSIX states that the filename will be chosen from one
+	 * of the old, new and index names (in that order) if
+	 * the file exists relative to CWD after -p stripping.
+	 */
+	for (i = 0; i < MAX_FILE; i++) {
+		if (names[i].path != NULL && names[i].exists) {
+			path = names[i].path;
 			break;
 		}
-	    }
 	}
-	else {
-	    next_intuit_at(beginning_of_this_line,p_input_line);
-	    break;
+	if (path == NULL && !assume_exists) {
+		/*
+		 * No files found, look for something we can checkout from
+		 * RCS/SCCS dirs.  Same order as above.
+		 */
+		for (i = 0; i < MAX_FILE; i++) {
+			if (names[i].path != NULL &&
+			    (path = checked_in(names[i].path)) != NULL)
+				break;
+		}
+		/*
+		 * Still no match?  Check to see if the diff could be creating
+		 * a new file.
+		 */
+		if (path == NULL && ok_to_create_file &&
+		    names[NEW_FILE].path != NULL)
+			path = names[NEW_FILE].path;
+	}
+
+	return path ? savestr(path) : NULL;
+}
+
+/*
+ * Choose the name of the file to be patched based the "best" one
+ * available.
+ */
+static char *
+best_name(const struct file_name *names, bool assume_exists)
+{
+	size_t min_components, min_baselen, min_len, tmp;
+	char *best = NULL;
+	int i;
+
+	/*
+	 * The "best" name is the one with the fewest number of path
+	 * components, the shortest basename length, and the shortest
+	 * overall length (in that order).  We only use the Index: file
+	 * if neither of the old or new files could be intuited from
+	 * the diff header.
+	 */
+	min_components = min_baselen = min_len = SIZE_MAX;
+	for (i = INDEX_FILE; i >= OLD_FILE; i--) {
+		if (names[i].path == NULL ||
+		    (!names[i].exists && !assume_exists))
+			continue;
+		if ((tmp = num_components(names[i].path)) > min_components)
+			continue;
+		min_components = tmp;
+		if ((tmp = strlen(basename(names[i].path))) > min_baselen)
+			continue;
+		min_baselen = tmp;
+		if ((tmp = strlen(names[i].path)) > min_len)
+			continue;
+		min_len = tmp;
+		best = names[i].path;
+	}
+	if (best == NULL) {
+		/*
+		 * No files found, look for something we can checkout from
+		 * RCS/SCCS dirs.  Logic is identical to that above...
+		 */
+		min_components = min_baselen = min_len = SIZE_MAX;
+		for (i = INDEX_FILE; i >= OLD_FILE; i--) {
+			if (names[i].path == NULL ||
+			    checked_in(names[i].path) == NULL)
+				continue;
+			if ((tmp = num_components(names[i].path)) > min_components)
+				continue;
+			min_components = tmp;
+			if ((tmp = strlen(basename(names[i].path))) > min_baselen)
+				continue;
+			min_baselen = tmp;
+			if ((tmp = strlen(names[i].path)) > min_len)
+				continue;
+			min_len = tmp;
+			best = names[i].path;
+		}
+		/*
+		 * Still no match?  Check to see if the diff could be creating
+		 * a new file.
+		 */
+		if (best == NULL && ok_to_create_file &&
+		    names[NEW_FILE].path != NULL)
+			best = names[NEW_FILE].path;
+	}
+
+	return best ? savestr(best) : NULL;
+}
+
+static size_t
+num_components(const char *path)
+{
+	size_t n;
+	const char *cp;
+
+	for (n = 0, cp = path; (cp = strchr(cp, '/')) != NULL; n++, cp++) {
+		while (*cp == '/')
+			cp++;		/* skip consecutive slashes */
 	}
-    }
-    if (skip_rest_of_patch)
-	return;
-    fprintf(pipefp, "w\n");
-    fprintf(pipefp, "q\n");
-    Fflush(pipefp);
-    Pclose(pipefp);
-    ignore_signals();
-    if (move_file(TMPOUTNAME, outname) < 0) {
-	toutkeep = TRUE;
-	chmod(TMPOUTNAME, filemode);
-    }
-    else
-	chmod(outname, filemode);
-    set_signals();
+	return n;
 }
diff --git a/usr.bin/patch/pch.h b/usr.bin/patch/pch.h
index 97a5b28..b7bf8e8 100644
--- a/usr.bin/patch/pch.h
+++ b/usr.bin/patch/pch.h
@@ -1,36 +1,56 @@
-/* $Header: pch.h,v 2.0.1.1 87/01/30 22:47:16 lwall Exp $
- *
- * $Log:	pch.h,v $
- * Revision 2.0.1.1  87/01/30  22:47:16  lwall
- * Added do_ed_script().
+/*	$OpenBSD: pch.h,v 1.9 2003/10/31 20:20:45 millert Exp $	*/
+
+/*
+ * patch - a program to apply diffs to original files
+ * 
+ * Copyright 1986, Larry Wall
  * 
- * Revision 2.0  86/09/17  15:39:57  lwall
- * Baseline for netwide release.
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following condition is met:
+ * 1. Redistributions of source code must retain the above copyright notice,
+ * this condition and the following disclaimer.
  * 
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * 
+ * -C option added in 1998, original code by Marc Espie, based on FreeBSD
+ * behaviour
  */
 
-EXT FILE *pfp INIT(Nullfp);		/* patch file pointer */
+#define OLD_FILE	0
+#define NEW_FILE	1
+#define INDEX_FILE	2
+#define MAX_FILE	3
+
+struct file_name {
+	char *path;
+	bool exists;
+};
 
-void re_patch();
-void open_patch_file();
-void set_hunkmax();
-void grow_hunkmax();
-bool there_is_another_patch();
-int intuit_diff_type();
-void next_intuit_at();
-void skip_to();
-bool another_hunk();
-bool pch_swap();
-char *pfetch();
-short pch_line_len();
-LINENUM pch_first();
-LINENUM pch_ptrn_lines();
-LINENUM pch_newfirst();
-LINENUM pch_repl_lines();
-LINENUM pch_end();
-LINENUM pch_context();
-LINENUM pch_hunk_beg();
-char pch_char();
-char *pfetch();
-char *pgets();
-void do_ed_script();
+void		re_patch(void);
+void		open_patch_file(const char *);
+void		set_hunkmax(void);
+bool		there_is_another_patch(void);
+bool		another_hunk(void);
+bool		pch_swap(void);
+char		*pfetch(LINENUM);
+short		pch_line_len(LINENUM);
+LINENUM		pch_first(void);
+LINENUM		pch_ptrn_lines(void);
+LINENUM		pch_newfirst(void);
+LINENUM		pch_repl_lines(void);
+LINENUM		pch_end(void);
+LINENUM		pch_context(void);
+LINENUM		pch_hunk_beg(void);
+char		pch_char(LINENUM);
+char		*pfetch(LINENUM);
+void		do_ed_script(void);
diff --git a/usr.bin/patch/util.c b/usr.bin/patch/util.c
index 5582d18..23a22b1 100644
--- a/usr.bin/patch/util.c
+++ b/usr.bin/patch/util.c
@@ -1,339 +1,425 @@
-#include "EXTERN.h"
+/*	$OpenBSD: util.c,v 1.27 2003/10/31 20:20:45 millert Exp $	*/
+
+/*
+ * patch - a program to apply diffs to original files
+ * 
+ * Copyright 1986, Larry Wall
+ * 
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following condition is met:
+ * 1. Redistributions of source code must retain the above copyright notice,
+ * this condition and the following disclaimer.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * 
+ * -C option added in 1998, original code by Marc Espie, based on FreeBSD
+ * behaviour
+ */
+
+#ifndef lint
+static const char     rcsid[] = "$OpenBSD: util.c,v 1.27 2003/10/31 20:20:45 millert Exp $";
+#endif /* not lint */
+
+#include <sys/param.h>
+#include <sys/stat.h>
+
+#include <ctype.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <libgen.h>
+#include <paths.h>
+#include <stdarg.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+
 #include "common.h"
-#include "INTERN.h"
 #include "util.h"
+#include "backupfile.h"
+#include "pathnames.h"
+
 
 /* Rename a file, copying it if necessary. */
 
 int
-move_file(from,to)
-char *from, *to;
+move_file(const char *from, const char *to)
 {
-    char bakname[512];
-    Reg1 char *s;
-    Reg2 int i;
-    Reg3 int fromfd;
+	int	fromfd;
+	ssize_t	i;
 
-    /* to stdout? */
+	/* to stdout? */
 
-    if (strEQ(to, "-")) {
+	if (strEQ(to, "-")) {
 #ifdef DEBUGGING
-	if (debug & 4)
-	    say2("Moving %s to stdout.\n", from);
+		if (debug & 4)
+			say("Moving %s to stdout.\n", from);
 #endif
-	fromfd = open(from, 0);
-	if (fromfd < 0)
-	    fatal2("patch: internal error, can't reopen %s\n", from);
-	while ((i=read(fromfd, buf, sizeof buf)) > 0)
-	    if (write(1, buf, i) != 1)
-		fatal1("patch: write failed\n");
-	Close(fromfd);
-	return 0;
-    }
-
-    Strcpy(bakname, to);
-    Strcat(bakname, origext?origext:ORIGEXT);
-    if (stat(to, &filestat) >= 0) {	/* output file exists */
-	dev_t to_device = filestat.st_dev;
-	ino_t to_inode  = filestat.st_ino;
-	char *simplename = bakname;
-	
-	for (s=bakname; *s; s++) {
-	    if (*s == '/')
-		simplename = s+1;
+		fromfd = open(from, O_RDONLY);
+		if (fromfd < 0)
+			pfatal("internal error, can't reopen %s", from);
+		while ((i = read(fromfd, buf, sizeof buf)) > 0)
+			if (write(STDOUT_FILENO, buf, i) != i)
+				pfatal("write failed");
+		close(fromfd);
+		return 0;
 	}
-	/* find a backup name that is not the same file */
-	while (stat(bakname, &filestat) >= 0 &&
-		to_device == filestat.st_dev && to_inode == filestat.st_ino) {
-	    for (s=simplename; *s && !islower(*s); s++) ;
-	    if (*s)
-		*s = toupper(*s);
-	    else
-		Strcpy(simplename, simplename+1);
+	if (backup_file(to) < 0) {
+		say("Can't backup %s, output is in %s: %s\n", to, from,
+		    strerror(errno));
+		return -1;
 	}
-	while (unlink(bakname) >= 0) ;	/* while() is for benefit of Eunice */
 #ifdef DEBUGGING
 	if (debug & 4)
-	    say3("Moving %s to %s.\n", to, bakname);
+		say("Moving %s to %s.\n", from, to);
 #endif
-	if (link(to, bakname) < 0) {
-	    say3("patch: can't backup %s, output is in %s\n",
-		to, from);
-	    return -1;
+	if (rename(from, to) < 0) {
+		if (errno != EXDEV || copy_file(from, to) < 0) {
+			say("Can't create %s, output is in %s: %s\n",
+			    to, from, strerror(errno));
+			return -1;
+		}
+	}
+	return 0;
+}
+
+/* Backup the original file.  */
+
+int
+backup_file(const char *orig)
+{
+	struct stat	filestat;
+	char		bakname[MAXPATHLEN], *s, *simplename;
+	dev_t		orig_device;
+	ino_t		orig_inode;
+
+	if (backup_type == none || stat(orig, &filestat) != 0)
+		return 0;			/* nothing to do */
+	orig_device = filestat.st_dev;
+	orig_inode = filestat.st_ino;
+
+	if (origprae) {
+		if (strlcpy(bakname, origprae, sizeof(bakname)) >= sizeof(bakname) ||
+		    strlcat(bakname, orig, sizeof(bakname)) >= sizeof(bakname))
+			fatal("filename %s too long for buffer\n", origprae);
+	} else {
+		if ((s = find_backup_file_name(orig)) == NULL)
+			fatal("out of memory\n");
+		if (strlcpy(bakname, s, sizeof(bakname)) >= sizeof(bakname))
+			fatal("filename %s too long for buffer\n", s);
+		free(s);
+	}
+
+	if ((simplename = strrchr(bakname, '/')) != NULL)
+		simplename = simplename + 1;
+	else
+		simplename = bakname;
+
+	/*
+	 * Find a backup name that is not the same file. Change the
+	 * first lowercase char into uppercase; if that isn't
+	 * sufficient, chop off the first char and try again.
+	 */
+	while (stat(bakname, &filestat) == 0 &&
+	    orig_device == filestat.st_dev && orig_inode == filestat.st_ino) {
+		/* Skip initial non-lowercase chars.  */
+		for (s = simplename; *s && !islower(*s); s++)
+			;
+		if (*s)
+			*s = toupper(*s);
+		else
+			memmove(simplename, simplename + 1,
+			    strlen(simplename + 1) + 1);
 	}
-	while (unlink(to) >= 0) ;
-    }
 #ifdef DEBUGGING
-    if (debug & 4)
-	say3("Moving %s to %s.\n", from, to);
+	if (debug & 4)
+		say("Moving %s to %s.\n", orig, bakname);
 #endif
-    if (link(from, to) < 0) {		/* different file system? */
-	Reg4 int tofd;
-	
-	tofd = creat(to, 0666);
-	if (tofd < 0) {
-	    say3("patch: can't create %s, output is in %s.\n",
-	      to, from);
-	    return -1;
+	if (rename(orig, bakname) < 0) {
+		if (errno != EXDEV || copy_file(orig, bakname) < 0)
+			return -1;
 	}
-	fromfd = open(from, 0);
-	if (fromfd < 0)
-	    fatal2("patch: internal error, can't reopen %s\n", from);
-	while ((i=read(fromfd, buf, sizeof buf)) > 0)
-	    if (write(tofd, buf, i) != i)
-		fatal1("patch: write failed\n");
-	Close(fromfd);
-	Close(tofd);
-    }
-    Unlink(from);
-    return 0;
+	return 0;
 }
 
-/* Copy a file. */
-
-void
-copy_file(from,to)
-char *from, *to;
+/*
+ * Copy a file.
+ */
+int
+copy_file(const char *from, const char *to)
 {
-    Reg3 int tofd;
-    Reg2 int fromfd;
-    Reg1 int i;
-    
-    tofd = creat(to, 0666);
-    if (tofd < 0)
-	fatal2("patch: can't create %s.\n", to);
-    fromfd = open(from, 0);
-    if (fromfd < 0)
-	fatal2("patch: internal error, can't reopen %s\n", from);
-    while ((i=read(fromfd, buf, sizeof buf)) > 0)
-	if (write(tofd, buf, i) != i)
-	    fatal2("patch: write (%s) failed\n", to);
-    Close(fromfd);
-    Close(tofd);
-}
+	int	tofd, fromfd;
+	ssize_t	i;
 
-/* Allocate a unique area for a string. */
+	tofd = open(to, O_CREAT|O_TRUNC|O_WRONLY, 0666);
+	if (tofd < 0)
+		return -1;
+	fromfd = open(from, O_RDONLY, 0);
+	if (fromfd < 0)
+		pfatal("internal error, can't reopen %s", from);
+	while ((i = read(fromfd, buf, sizeof buf)) > 0)
+		if (write(tofd, buf, i) != i)
+			pfatal("write to %s failed", to);
+	close(fromfd);
+	close(tofd);
+	return 0;
+}
 
+/*
+ * Allocate a unique area for a string.
+ */
 char *
-savestr(s)
-Reg1 char *s;
+savestr(const char *s)
 {
-    Reg3 char *rv;
-    Reg2 char *t;
-
-    if (!s)
-	s = "Oops";
-    t = s;
-    while (*t++);
-    rv = malloc((MEM) (t - s));
-    if (rv == Nullch) {
-	if (using_plan_a)
-	    out_of_mem = TRUE;
-	else
-	    fatal1("patch: out of memory (savestr)\n");
-    }
-    else {
-	t = rv;
-	while (*t++ = *s++);
-    }
-    return rv;
+	char	*rv;
+
+	if (!s)
+		s = "Oops";
+	rv = strdup(s);
+	if (rv == NULL) {
+		if (using_plan_a)
+			out_of_mem = true;
+		else
+			fatal("out of memory\n");
+	}
+	return rv;
 }
 
-#if defined(lint) && defined(CANVARARG)
-
-/*VARARGS ARGSUSED*/
-say(pat) char *pat; { ; }
-/*VARARGS ARGSUSED*/
-fatal(pat) char *pat; { ; }
-/*VARARGS ARGSUSED*/
-ask(pat) char *pat; { ; }
-
-#else
-
-/* Vanilla terminal output (buffered). */
-
+/*
+ * Vanilla terminal output (buffered).
+ */
 void
-say(pat,arg1,arg2,arg3)
-char *pat;
-int arg1,arg2,arg3;
+say(const char *fmt, ...)
 {
-    fprintf(stderr, pat, arg1, arg2, arg3);
-    Fflush(stderr);
-}
+	va_list	ap;
 
-/* Terminal output, pun intended. */
+	va_start(ap, fmt);
+	vfprintf(stderr, fmt, ap);
+	va_end(ap);
+	fflush(stderr);
+}
 
-void				/* very void */
-fatal(pat,arg1,arg2,arg3)
-char *pat;
-int arg1,arg2,arg3;
+/*
+ * Terminal output, pun intended.
+ */
+void
+fatal(const char *fmt, ...)
 {
-    void my_exit();
+	va_list	ap;
 
-    say(pat, arg1, arg2, arg3);
-    my_exit(1);
+	va_start(ap, fmt);
+	fprintf(stderr, "patch: **** ");
+	vfprintf(stderr, fmt, ap);
+	va_end(ap);
+	my_exit(2);
 }
 
-/* Get a response from the user, somehow or other. */
-
+/*
+ * Say something from patch, something from the system, then silence . . .
+ */
 void
-ask(pat,arg1,arg2,arg3)
-char *pat;
-int arg1,arg2,arg3;
+pfatal(const char *fmt, ...)
 {
-    int ttyfd;
-    int r;
-    bool tty2 = isatty(2);
-
-    Sprintf(buf, pat, arg1, arg2, arg3);
-    Fflush(stderr);
-    write(2, buf, strlen(buf));
-    if (tty2) {				/* might be redirected to a file */
-	r = read(2, buf, sizeof buf);
-    }
-    else if (isatty(1)) {		/* this may be new file output */
-	Fflush(stdout);
-	write(1, buf, strlen(buf));
-	r = read(1, buf, sizeof buf);
-    }
-    else if ((ttyfd = open("/dev/tty", 2)) >= 0 && isatty(ttyfd)) {
-					/* might be deleted or unwriteable */
-	write(ttyfd, buf, strlen(buf));
-	r = read(ttyfd, buf, sizeof buf);
-	Close(ttyfd);
-    }
-    else if (isatty(0)) {		/* this is probably patch input */
-	Fflush(stdin);
-	write(0, buf, strlen(buf));
-	r = read(0, buf, sizeof buf);
-    }
-    else {				/* no terminal at all--default it */
-	buf[0] = '\n';
-	r = 1;
-    }
-    if (r <= 0)
-	buf[0] = 0;
-    else
-	buf[r] = '\0';
-    if (!tty2)
-	say1(buf);
+	va_list	ap;
+	int	errnum = errno;
+
+	fprintf(stderr, "patch: **** ");
+	va_start(ap, fmt);
+	vfprintf(stderr, fmt, ap);
+	va_end(ap);
+	fprintf(stderr, ": %s\n", strerror(errnum));
+	my_exit(2);
 }
-#endif lint
-
-/* How to handle certain events when not in a critical region. */
 
+/*
+ * Get a response from the user via /dev/tty
+ */
 void
-set_signals()
+ask(const char *fmt, ...)
 {
-    void my_exit();
-
-#ifndef lint
-    if (signal(SIGHUP, SIG_IGN) != SIG_IGN)
-	Signal(SIGHUP, my_exit);
-    if (signal(SIGINT, SIG_IGN) != SIG_IGN)
-	Signal(SIGINT, my_exit);
-#endif
+	va_list	ap;
+	ssize_t	nr;
+	static	int ttyfd = -1;
+
+	va_start(ap, fmt);
+	vfprintf(stdout, fmt, ap);
+	va_end(ap);
+	fflush(stdout);
+	if (ttyfd < 0)
+		ttyfd = open(_PATH_TTY, O_RDONLY);
+	if (ttyfd >= 0) {
+		if ((nr = read(ttyfd, buf, sizeof(buf))) > 0 &&
+		    buf[nr - 1] == '\n')
+			buf[nr - 1] = '\0';
+	}
+	if (ttyfd < 0 || nr <= 0) {
+		/* no tty or error reading, pretend user entered 'return' */
+		putchar('\n');
+		buf[0] = '\0';
+	}
 }
 
-/* How to handle certain events when in a critical region. */
+/*
+ * How to handle certain events when not in a critical region.
+ */
+void
+set_signals(int reset)
+{
+	static sig_t	hupval, intval;
+
+	if (!reset) {
+		hupval = signal(SIGHUP, SIG_IGN);
+		if (hupval != SIG_IGN)
+			hupval = (sig_t) my_exit;
+		intval = signal(SIGINT, SIG_IGN);
+		if (intval != SIG_IGN)
+			intval = (sig_t) my_exit;
+	}
+	signal(SIGHUP, hupval);
+	signal(SIGINT, intval);
+}
 
+/*
+ * How to handle certain events when in a critical region.
+ */
 void
-ignore_signals()
+ignore_signals(void)
 {
-#ifndef lint
-    Signal(SIGHUP, SIG_IGN);
-    Signal(SIGINT, SIG_IGN);
-#endif
+	signal(SIGHUP, SIG_IGN);
+	signal(SIGINT, SIG_IGN);
 }
 
-/* Make sure we'll have the directories to create a file. */
+/*
+ * Make sure we'll have the directories to create a file. If `striplast' is
+ * true, ignore the last element of `filename'.
+ */
 
 void
-makedirs(filename,striplast)
-Reg1 char *filename;
-bool striplast;
+makedirs(const char *filename, bool striplast)
 {
-    char tmpbuf[256];
-    Reg2 char *s = tmpbuf;
-    char *dirv[20];
-    Reg3 int i;
-    Reg4 int dirvp = 0;
-
-    while (*filename) {
-	if (*filename == '/') {
-	    filename++;
-	    dirv[dirvp++] = s;
-	    *s++ = '\0';
-	}
-	else {
-	    *s++ = *filename++;
+	char	*tmpbuf;
+
+	if ((tmpbuf = strdup(filename)) == NULL)
+		fatal("out of memory\n");
+
+	if (striplast) {
+		char	*s = strrchr(tmpbuf, '/');
+		if (s == NULL)
+			return;	/* nothing to be done */
+		*s = '\0';
 	}
-    }
-    *s = '\0';
-    dirv[dirvp] = s;
-    if (striplast)
-	dirvp--;
-    if (dirvp < 0)
-	return;
-    strcpy(buf, "mkdir");
-    s = buf;
-    for (i=0; i<=dirvp; i++) {
-	while (*s) s++;
-	*s++ = ' ';
-	strcpy(s, tmpbuf);
-	*dirv[i] = '/';
-    }
-    system(buf);
-}
+	if (snprintf(buf, sizeof(buf), "%s -p %s", _PATH_MKDIR, tmpbuf)
+	    >= sizeof(buf))
+		fatal("buffer too small to hold %.20s...\n", tmpbuf);
 
-/* Make filenames more reasonable. */
+	if (system(buf))
+		pfatal("%.40s failed", buf);
+}
 
+/*
+ * Make filenames more reasonable.
+ */
 char *
-fetchname(at,strip_leading,assume_exists)
-char *at;
-int strip_leading;
-int assume_exists;
+fetchname(const char *at, bool *exists, int strip_leading)
 {
-    char *s;
-    char *name;
-    Reg1 char *t;
-    char tmpbuf[200];
-
-    if (!at)
-	return Nullch;
-    s = savestr(at);
-    for (t=s; isspace(*t); t++) ;
-    name = t;
+	char		*fullname, *name, *t;
+	int		sleading;
+	struct stat	filestat;
+
+	if (at == NULL || *at == '\0')
+		return NULL;
+	while (isspace(*at))
+		at++;
 #ifdef DEBUGGING
-    if (debug & 128)
-	say4("fetchname %s %d %d\n",name,strip_leading,assume_exists);
+	if (debug & 128)
+		say("fetchname %s %d\n", at, strip_leading);
 #endif
-    if (strnEQ(name, "/dev/null", 9))	/* so files can be created by diffing */
-	return Nullch;			/*   against /dev/null. */
-    for (; *t && !isspace(*t); t++)
-	if (*t == '/')
-	    if (--strip_leading >= 0)
-		name = t+1;
-    *t = '\0';
-    if (name != s && *s != '/') {
-	name[-1] = '\0';
-	if (stat(s, &filestat) && filestat.st_mode & S_IFDIR) {
-	    name[-1] = '/';
-	    name=s;
+	/* So files can be created by diffing against /dev/null.  */
+	if (strnEQ(at, _PATH_DEVNULL, sizeof(_PATH_DEVNULL) - 1))
+		return NULL;
+	name = fullname = t = savestr(at);
+
+	/* Strip off up to `strip_leading' path components and NUL terminate. */
+	for (sleading = strip_leading; *t != '\0' && !isspace(*t); t++) {
+		if (t[0] == '/' && t[1] != '/' && t[1] != '\0')
+			if (--sleading >= 0)
+				name = t + 1;
 	}
-    }
-    name = savestr(name);
-    Sprintf(tmpbuf, "RCS/%s", name);
-    free(s);
-    if (stat(name, &filestat) < 0 && !assume_exists) {
-	Strcat(tmpbuf, RCSSUFFIX);
-	if (stat(tmpbuf, &filestat) < 0 && stat(tmpbuf+4, &filestat) < 0) {
-	    Sprintf(tmpbuf, "SCCS/%s%s", SCCSPREFIX, name);
-	    if (stat(tmpbuf, &filestat) < 0 && stat(tmpbuf+5, &filestat) < 0) {
-		free(name);
-		name = Nullch;
-	    }
+	*t = '\0';
+
+	/*
+	 * If no -p option was given (957 is the default value!), we were
+	 * given a relative pathname, and the leading directories that we
+	 * just stripped off all exist, put them back on.
+	 */
+	if (strip_leading == 957 && name != fullname && *fullname != '/') {
+		name[-1] = '\0';
+		if (stat(fullname, &filestat) == 0 && S_ISDIR(filestat.st_mode)) {
+			name[-1] = '/';
+			name = fullname;
+		}
 	}
-    }
-    return name;
+	name = savestr(name);
+	free(fullname);
+
+	*exists = stat(name, &filestat) == 0;
+	return name;
+}
+
+/*
+ * Takes the name returned by fetchname and looks in RCS/SCCS directories
+ * for a checked in version.
+ */
+char *
+checked_in(char *file)
+{
+	char		*filebase, *filedir, tmpbuf[MAXPATHLEN];
+	struct stat	filestat;
+
+	filebase = basename(file);
+	filedir = dirname(file);
+
+#define try(f, a1, a2, a3) \
+(snprintf(tmpbuf, sizeof tmpbuf, f, a1, a2, a3), stat(tmpbuf, &filestat) == 0)
+
+	if (try("%s/RCS/%s%s", filedir, filebase, RCSSUFFIX) ||
+	    try("%s/RCS/%s%s", filedir, filebase, "") ||
+	    try("%s/%s%s", filedir, filebase, RCSSUFFIX) ||
+	    try("%s/SCCS/%s%s", filedir, SCCSPREFIX, filebase) ||
+	    try("%s/%s%s", filedir, SCCSPREFIX, filebase))
+		return file;
+
+	return NULL;
+}
+
+void
+version(void)
+{
+	fprintf(stderr, "Patch version 2.0-12u8-OpenBSD\n");
+	my_exit(EXIT_SUCCESS);
+}
+
+/*
+ * Exit with cleanup.
+ */
+void
+my_exit(int status)
+{
+	unlink(TMPINNAME);
+	if (!toutkeep)
+		unlink(TMPOUTNAME);
+	if (!trejkeep)
+		unlink(TMPREJNAME);
+	unlink(TMPPATNAME);
+	exit(status);
 }
diff --git a/usr.bin/patch/util.h b/usr.bin/patch/util.h
index 9896c63..0ec1870 100644
--- a/usr.bin/patch/util.h
+++ b/usr.bin/patch/util.h
@@ -1,74 +1,47 @@
-/* $Header: util.h,v 2.0 86/09/17 15:40:06 lwall Exp $
- *
- * $Log:	util.h,v $
- * Revision 2.0  86/09/17  15:40:06  lwall
- * Baseline for netwide release.
+/*	$OpenBSD: util.h,v 1.12 2003/10/31 20:20:45 millert Exp $	*/
+
+/*
+ * patch - a program to apply diffs to original files
+ * 
+ * Copyright 1986, Larry Wall
+ * 
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following condition is met:
+ * 1. Redistributions of source code must retain the above copyright notice,
+ * this condition and the following disclaimer.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
  * 
+ * -C option added in 1998, original code by Marc Espie, based on FreeBSD
+ * behaviour
  */
 
-/* and for those machine that can't handle a variable argument list */
-
-#ifdef CANVARARG
-
-#define say1 say
-#define say2 say
-#define say3 say
-#define say4 say
-#define ask1 ask
-#define ask2 ask
-#define ask3 ask
-#define ask4 ask
-#define fatal1 fatal
-#define fatal2 fatal
-#define fatal3 fatal
-#define fatal4 fatal
-
-#else /* hope they allow multi-line macro actual arguments */
-
-#ifdef lint
-
-#define say1(a) say(a, 0, 0, 0)
-#define say2(a,b) say(a, (b)==(b), 0, 0)
-#define say3(a,b,c) say(a, (b)==(b), (c)==(c), 0)
-#define say4(a,b,c,d) say(a, (b)==(b), (c)==(c), (d)==(d))
-#define ask1(a) ask(a, 0, 0, 0)
-#define ask2(a,b) ask(a, (b)==(b), 0, 0)
-#define ask3(a,b,c) ask(a, (b)==(b), (c)==(c), 0)
-#define ask4(a,b,c,d) ask(a, (b)==(b), (c)==(c), (d)==(d))
-#define fatal1(a) fatal(a, 0, 0, 0)
-#define fatal2(a,b) fatal(a, (b)==(b), 0, 0)
-#define fatal3(a,b,c) fatal(a, (b)==(b), (c)==(c), 0)
-#define fatal4(a,b,c,d) fatal(a, (b)==(b), (c)==(c), (d)==(d))
-
-#else /* lint */
-    /* if this doesn't work, try defining CANVARARG above */
-#define say1(a) say(a, Nullch, Nullch, Nullch)
-#define say2(a,b) say(a, b, Nullch, Nullch)
-#define say3(a,b,c) say(a, b, c, Nullch)
-#define say4 say
-#define ask1(a) ask(a, Nullch, Nullch, Nullch)
-#define ask2(a,b) ask(a, b, Nullch, Nullch)
-#define ask3(a,b,c) ask(a, b, c, Nullch)
-#define ask4 ask
-#define fatal1(a) fatal(a, Nullch, Nullch, Nullch)
-#define fatal2(a,b) fatal(a, b, Nullch, Nullch)
-#define fatal3(a,b,c) fatal(a, b, c, Nullch)
-#define fatal4 fatal
-
-#endif /* lint */
-
-/* if neither of the above work, join all multi-line macro calls. */
-#endif
-
-EXT char serrbuf[BUFSIZ];		/* buffer for stderr */
-
-char *fetchname();
-int move_file();
-void copy_file();
-void say();
-void fatal();
-void ask();
-char *savestr();
-void set_signals();
-void ignore_signals();
-void makedirs();
+char		*fetchname(const char *, bool *, int);
+char		*checked_in(char *);
+int		backup_file(const char *);
+int		move_file(const char *, const char *);
+int		copy_file(const char *, const char *);
+void		say(const char *, ...)
+		    __attribute__((__format__(__printf__, 1, 2)));
+void		fatal(const char *, ...)
+		    __attribute__((__format__(__printf__, 1, 2)));
+void		pfatal(const char *, ...)
+		    __attribute__((__format__(__printf__, 1, 2)));
+void		ask(const char *, ...)
+		    __attribute__((__format__(__printf__, 1, 2)));
+char		*savestr(const char *);
+void		set_signals(int);
+void		ignore_signals(void);
+void		makedirs(const char *, bool);
+void		version(void);
+void            my_exit(int) __attribute__((noreturn));