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author | gad <gad@FreeBSD.org> | 2004-08-01 20:45:54 +0000 |
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committer | gad <gad@FreeBSD.org> | 2004-08-01 20:45:54 +0000 |
commit | 278fb1a5b03afd90c559d3c6ea91fa325b05b245 (patch) | |
tree | 4dfc5f08ffa0e4682af5a54daaf205d139c125ee /usr.bin/patch/backupfile.c | |
parent | 75f4088eb71e33df49f38e40409a74ea045e3ed8 (diff) | |
download | FreeBSD-src-278fb1a5b03afd90c559d3c6ea91fa325b05b245.zip FreeBSD-src-278fb1a5b03afd90c559d3c6ea91fa325b05b245.tar.gz |
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.
Diffstat (limited to 'usr.bin/patch/backupfile.c')
-rw-r--r-- | usr.bin/patch/backupfile.c | 238 |
1 files changed, 238 insertions, 0 deletions
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); +} |