Grok gtags too.

7 files changed, 425 insertions, 42 deletions

diff --git a/usr.bin/more/command.c b/usr.bin/more/command.c
index 62ed6e8..6d34a56 100644
--- a/usr.bin/more/command.c
+++ b/usr.bin/more/command.c
@@ -38,7 +38,7 @@ static char sccsid[] = "@(#)command.c	8.1 (Berkeley) 6/6/93";
 
 #ifndef lint
 static const char rcsid[] =
-        "$Id$";
+        "$Id: command.c,v 1.11 1999/05/30 18:06:52 hoek Exp $";
 #endif /* not lint */
 
 #include <sys/param.h>
@@ -364,6 +364,7 @@ commands()
 	register int action;
 	static int default_hscroll = 1;
 	static int saved_horiz_off = NO_HORIZ_OFF;
+	extern char *tagfile;
 
 	last_mca = 0;
 	scroll = (sc_height + 1) / 2;
@@ -569,6 +570,24 @@ again:		if (sigs)
 			start_mca(A_TAGFILE, "Tag: ");
 			c = getcc();
 			goto again;
+		case A_NEXTTAG:
+			if (number <= 0)
+				number = 1;
+			nexttag(number);
+			if (tagfile == NULL)
+				break;
+			if (edit(tagfile))
+				(void)tagsearch();
+			break;
+		case A_PREVTAG:
+			if (number <= 0)
+				number = 1;
+			prevtag(number);
+			if (tagfile == NULL)
+				break;
+			if (edit(tagfile))
+				(void)tagsearch();
+			break;
 		case A_FILE_LIST:		/* show list of file names */
 			CMD_EXEC;
 			showlist();
diff --git a/usr.bin/more/decode.c b/usr.bin/more/decode.c
index 8edcdcf..2d490fa 100644
--- a/usr.bin/more/decode.c
+++ b/usr.bin/more/decode.c
@@ -38,7 +38,7 @@ static char sccsid[] = "@(#)decode.c	8.1 (Berkeley) 6/6/93";
 
 #ifndef lint
 static const char rcsid[] =
-        "$Id$";
+        "$Id: decode.c,v 1.2 1999/05/30 18:06:53 hoek Exp $";
 #endif /* not lint */
 
 /*
@@ -133,6 +133,8 @@ static char cmdtable[] = {
 	'q',0,				A_QUIT,
 	':','q',0,			A_QUIT,
 	':','t',0,			A_TAGFILE,
+	'T',0,				A_PREVTAG,
+	't',0,				A_NEXTTAG,
 	':', 'a', 0,			A_FILE_LIST,
 	'Z','Z',0,			A_QUIT,
 };
diff --git a/usr.bin/more/less.h b/usr.bin/more/less.h
index 805bee0..deb7ec5 100644
--- a/usr.bin/more/less.h
+++ b/usr.bin/more/less.h
@@ -33,7 +33,7 @@
  *
  *	@(#)less.h	8.1 (Berkeley) 6/6/93
  *
- *	$Id$
+ *	$Id: less.h,v 1.3 1999/05/30 18:06:55 hoek Exp $
  */
 
 #define	NULL_POSITION	((off_t)(-1))
@@ -90,3 +90,5 @@
 #define	A_L_COL			28
 #define	A_R_COL			29
 #define	A_HOME			30
+#define	A_NEXTTAG		31
+#define	A_PREVTAG		32
diff --git a/usr.bin/more/main.c b/usr.bin/more/main.c
index 8441653..52e81bf 100644
--- a/usr.bin/more/main.c
+++ b/usr.bin/more/main.c
@@ -45,7 +45,7 @@ static char sccsid[] = "@(#)main.c	8.1 (Berkeley) 6/7/93";
 
 #ifndef lint
 static const char rcsid[] =
-	"$Id$";
+	"$Id: main.c,v 1.11 1999/05/30 18:06:56 hoek Exp $";
 #endif /* not lint */
 
 /*
@@ -82,7 +82,8 @@ extern int	tagoption;
 /*
  * Edit a new file.
  * Filename "-" means standard input.
- * No filename means the "current" file, from the command line.
+ * No filename means the "current" file, from the command line.  If called
+ * with the same filename in succession, filename will be closed and reopened.
  */
 edit(filename)
 	register char *filename;
diff --git a/usr.bin/more/more.1 b/usr.bin/more/more.1
index ec866d0..ee4438d 100644
--- a/usr.bin/more/more.1
+++ b/usr.bin/more/more.1
@@ -245,6 +245,10 @@ Examine the previous file.
 If a number N is specified, the N-th previous file is examined.
 .It Ic \&:t
 Go to supplied tag.
+.It Ic t
+Go forward in tag queue [gtags only].
+.It Ic T
+Go backward in tag queue [gtags only].
 .It Ic v
 Invokes an editor to edit the current file being viewed.
 The editor is taken from the environment variable
@@ -286,6 +290,8 @@ Specifies terminal type, used by more to get the terminal
 characteristics necessary to manipulate the screen.
 .El
 .Sh SEE ALSO
+.Xr gtags 1 ,
+.Xr global 1 ,
 .Xr ctags 1 ,
 .Xr vi 1
 .Sh BUGS
diff --git a/usr.bin/more/more.help b/usr.bin/more/more.help
index fcef82f..eb78cb4 100644
--- a/usr.bin/more/more.help
+++ b/usr.bin/more/more.help
@@ -31,6 +31,7 @@
   :n, N        *  Examine the next file.
   :p, P        *  Examine the previous file.
   :t [tag]        Examine the tag.
+  t, T            Move forward or backward N tags in the gtags queue.
   v               Run an editor on the current file.
 
   =, ^G           Print current file name and stats.
diff --git a/usr.bin/more/tags.c b/usr.bin/more/tags.c
index 5486567..706a2e7 100644
--- a/usr.bin/more/tags.c
+++ b/usr.bin/more/tags.c
@@ -2,6 +2,7 @@
  * Copyright (c) 1988 Mark Nudleman
  * Copyright (c) 1988, 1993
  *	The Regents of the University of California.  All rights reserved.
+ * Portions copyright (c) 1996, 1997, 1998 Shigio Yamaguchi.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ -36,43 +37,158 @@
 static char sccsid[] = "@(#)tags.c	8.1 (Berkeley) 6/6/93";
 #endif /* not lint */
 
+#ifndef lint
+static const char rcsid[] =
+        "$Id$";
+#endif /* not lint */
+
 #include <sys/types.h>
+#include <sys/queue.h>
+
+#include <ctype.h>
 #include <stdio.h>
+#include <stdlib.h>
 #include <string.h>
-#include <less.h>
+
+#include "less.h"
 
 #define	WHITESP(c)	((c)==' ' || (c)=='\t')
 
-char *tagfile;
-char *tagpattern;
+extern int sigs;
+char *tagfile;		/* Name of source file containing current tag */
+
+static enum { CTAGS, GTAGS } tagstyle = GTAGS;
+static char *findctag(), *findgtag(), *nextgtag(), *prevgtag();
+static ctagsearch(), gtagsearch();
+
+/*
+ * Load information about the tag.  The global variable tagfile will point to
+ * the file that contains the tag, or will be NULL if information could not be
+ * found (in which case an error message will have been printed).  After
+ * loading the file named by tagfile, tagsearch() should be called to
+ * set the current position to the tag.
+ */
+findtag(tag)
+	char *tag;	/* The tag to load */
+{
+	/*
+	 * Try using gtags or ctags first, as indicated by tagstyle.  If
+	 * that fails, try the other.  Someday there may even be a way to
+	 * assert a certain tagstyle...
+	 */
+	switch(tagstyle) {
+	case CTAGS:
+		tagfile = findctag(tag);
+		if (!tagfile && (tagfile = findgtag(tag))) tagstyle = GTAGS;
+		if (tagfile) return;
+		break;
+	case GTAGS:
+		/* Would be nice to print the number of tag references
+		 * we found (for nexttag() and prevtag()) in a (not-)error()
+		 * message. */
+		tagfile = findgtag(tag);
+		if (!tagfile && (tagfile = findctag(tag))) tagstyle = CTAGS;
+		if (tagfile) return;
+		break;
+	}
 
-static char *tags = "tags";
+	error("could not find relevent tag information");
+}
+
+/*
+ * Load information about the next number'th tag, if the last findtag() call
+ * found multiple tag references.  The global variable tagfile will point to the
+ * file that contains the tag, or will be NULL if information could not be
+ * found (in which case an error message will have been printed).  After
+ * loading the file named by tagfile, tagsearch() should be called to set
+ * the current position to the tag.
+ */
+nexttag(number)
+	int number;	/* How many tags to go forward by */
+{
+	if (number < 0) number = -number;  /* positive only, please */
+
+	switch(tagstyle) {
+	case CTAGS:
+		break;
+	case GTAGS:
+		while (number--) tagfile = nextgtag();
+		break;
+	}
+	if (!tagfile)
+		error("no next tag");
+}
+
+/*
+ * The antithesis to nexttag().
+ */
+prevtag(number)
+	int number;	/* How many tags to go backwards by */
+{
+	if (number < 0) number = -number;  /* positive only, please */
+
+	switch(tagstyle) {
+	case CTAGS:
+		break;
+	case GTAGS:
+		while (number--) tagfile = prevgtag();
+		break;
+	}
+	if (!tagfile)
+		error("no previous tag");
+}
+
+/*
+ * Try and position the currently loaded file at the last tag that was
+ * succesfully passed to findtag() or chosen with nexttag() and prevtag().
+ * An error message will be printed if unsuccessful.
+ */
+tagsearch()
+{
+	switch(tagstyle) {
+	case CTAGS:
+		if (ctagsearch())
+			error("could not locate ctag");
+		return;
+	case GTAGS:
+		if (gtagsearch())
+			error("could not locate gtag");
+		return;
+	}
+}
+
+
+/*******************************************************************************
+ *
+ * ctags
+ *
+ */
 
 extern int linenums;
-extern int sigs;
 extern char *line;
 
+static char *ctagpattern;
+
 /*
- * Find a tag in the "tags" file.
- * Sets "tagfile" to the name of the file containing the tag,
- * and "tagpattern" to the search pattern which should be used
- * to find the tag.
+ * Find specified tag in the ctags(1)-format tag file ctagfile.  Returns
+ * pointer to a static buffer holding the name of the file containing
+ * the tag.  Returns NULL on failure.  The next call to ctagsearch() will
+ * position the currently loaded file at the tag.
  */
-findtag(tag)
-	register char *tag;
+static char *
+findctag(tag)
+	register char *tag;	/* tag to search for */
 {
 	register char *p;
 	register FILE *f;
 	register int taglen;
 	int search_char;
-	static char tline[200];
+	static char tline[200];  /* XXX should be dynamic */
+	const char *ctagfile = "tags";
+	char *retr;
 
-	if ((f = fopen(tags, "r")) == NULL)
-	{
-		error("No tags file");
-		tagfile = NULL;
-		return;
-	}
+	if ((f = fopen(ctagfile, "r")) == NULL)
+		return (NULL);
 
 	taglen = strlen(tag);
 
@@ -81,6 +197,9 @@ findtag(tag)
 	 */
 	while (fgets(tline, sizeof(tline), f) != NULL)
 	{
+		if (sigs)
+			break;  /* abandon */
+
 		if (strncmp(tag, tline, taglen) != 0 || !WHITESP(tline[taglen]))
 			continue;
 
@@ -92,10 +211,9 @@ findtag(tag)
 		 * search characters.
 		 * Parse the line and extract these parts.
 		 */
-		tagfile = tagpattern = NULL;
 
 		/*
-		 * Skip over the whitespace after the tag name.
+		 * Skip over the tag and the whitespace after the tag name.
 		 */
 		for (p = tline;  !WHITESP(*p) && *p != '\0';  p++)
 			continue;
@@ -107,9 +225,9 @@ findtag(tag)
 
 		/*
 		 * Save the file name.
-		 * Skip over the whitespace after the file name.
+		 * Skip over the filename and whitespace after the file name.
 		 */
-		tagfile = p;
+		retr = p;
 		while (!WHITESP(*p) && *p != '\0')
 			p++;
 		*p++ = '\0';
@@ -127,7 +245,7 @@ findtag(tag)
 		search_char = *p++;
 		if (*p == '^')
 			p++;
-		tagpattern = p;
+		ctagpattern = p;  /* cock ctagsearch() */
 		while (*p != search_char && *p != '\0')
 			p++;
 		if (p[-1] == '$')
@@ -135,23 +253,26 @@ findtag(tag)
 		*p = '\0';
 
 		(void)fclose(f);
-		return;
+		return (retr);
 	}
 	(void)fclose(f);
-	error("No such tag in tags file");
-	tagfile = NULL;
+	return (NULL);
 }
 
 /*
- * Search for a tag.
+ * Locate the tag that was loaded by findctag().
  * This is a stripped-down version of search().
  * We don't use search() for several reasons:
  *   -	We don't want to blow away any search string we may have saved.
  *   -	The various regular-expression functions (from different systems:
  *	regcmp vs. re_comp) behave differently in the presence of
  *	parentheses (which are almost always found in a tag).
+ *
+ * Returns -1 if it was unable to position at the requested pattern,
+ * 0 otherwise.
  */
-tagsearch()
+static
+ctagsearch()
 {
 	off_t pos, linepos, forw_raw_line();
 	int linenum;
@@ -166,7 +287,7 @@ tagsearch()
 		 * until we hit end-of-file.
 		 */
 		if (sigs)
-			return (1);
+			return (-1);
 
 		/*
 		 * Read the next line, and save the
@@ -178,13 +299,7 @@ tagsearch()
 			linenum++;
 
 		if (pos == NULL_POSITION)
-		{
-			/*
-			 * We hit EOF without a match.
-			 */
-			error("Tag not found");
-			return (1);
-		}
+			return (-1);  /* Tag not found. */
 
 		/*
 		 * If we're using line numbers, we might as well
@@ -197,10 +312,247 @@ tagsearch()
 		/*
 		 * Test the line to see if we have a match.
 		 */
-		if (strcmp(tagpattern, line) == 0)
+		if (strcmp(ctagpattern, line) == 0)
 			break;
 	}
 
 	jump_loc(linepos);
 	return (0);
 }
+
+
+/*******************************************************************************
+ *
+ * gtags
+ *
+ */
+
+/*
+ * The findgtag() and getentry() functions are stolen, more or less, from the
+ * patches to nvi-1.79 included in Shigio Yamaguchi's global-3.42 distribution.
+ */
+
+/*
+ * The queue of tags generated by the last findgtag() call.
+ */
+static CIRCLEQ_HEAD(gtag_q, gtag) gtag_q;
+struct gtag {
+	CIRCLEQ_ENTRY(gtag) ptrs;
+	char *file;	/* source file containing the tag */
+	int line;	/* appropriate line number of source file */
+};
+static struct gtag *curgtag;
+static getentry();
+
+/*
+ * The findgtag() will try and load information about the requested tag.
+ * It does this by calling "global -x tag; global -xr tag;" and storing the
+ * parsed output for future use by gtagsearch_f() and gtagsearch_b().  A
+ * pointer to a static buffer containing the name of the source file will
+ * be returned, or NULL on failure.  The first filename printed by global is
+ * returned (hopefully the function definition) and the other filenames may
+ * be accessed by nextgtag() and prevgtag().
+ */
+static char *
+findgtag(tag)
+	char *tag;		/* tag to load */
+{
+	struct gtag *gtag_p1, *gtag_p2;
+	char command[512];
+	char buf[256];
+	FILE *fp;
+
+	if (!tag) return (NULL);  /* Sanity check */
+
+	/* Clear any existing tag circle queue */
+	/* XXX Ideally, we wouldn't do this until after we know that we
+	 * can load some other tag information. */
+	curgtag = NULL;
+	gtag_p1 = gtag_q.cqh_first;
+	if (gtag_p1) while (gtag_p1 != (void *)&gtag_q) {
+		gtag_p2 = gtag_p1->ptrs.cqe_next;
+		free(gtag_p1);
+		gtag_p1 = gtag_p2;
+	}
+
+	/* Allocate and initialize the tag queue structure. */
+	CIRCLEQ_INIT(&gtag_q);
+
+	/* Get our data from global(1) */
+	snprintf(command, sizeof(command),
+	    "(global -x '%s'; global -xr '%s') 2>/dev/null", tag, tag);
+	if (fp = popen(command, "r")) {
+		while (fgets(buf, sizeof(buf), fp)) {
+			char *name, *file, *line;
+
+			if (sigs) {
+				pclose(fp);
+				return (NULL);
+			}
+				
+			/* chop(buf) */
+			if (buf[strlen(buf) - 1] == '\n')
+				buf[strlen(buf) - 1] = 0;
+			else
+				while (fgetc(fp) != '\n')
+					;
+
+ 			if (getentry(buf, &name, &file, &line)) {
+				/*
+				 * Couldn't parse this line for some reason.
+				 * We'll just pretend it never happened.
+				 */
+				break;
+			}
+
+			/* Add to queue */
+			gtag_p1 = malloc(sizeof(struct gtag));
+			if (!gtag_p1) {
+				pclose(fp);
+				error("malloc() failed");
+				return (NULL);
+			}
+			gtag_p1->file = file;
+			gtag_p1->file = malloc(strlen(file));
+			if (!gtag_p1->file) {
+				pclose(fp);
+				error("malloc() failed");
+				return (NULL);
+			}
+			strcpy(gtag_p1->file, file);
+			gtag_p1->line = atoi(line);
+			CIRCLEQ_INSERT_TAIL(&gtag_q, gtag_p1, ptrs);
+		}
+		pclose(fp);
+	}
+
+	/* Check to see if we found anything. */
+	if (gtag_q.cqh_first == (void *)&gtag_q)
+		return (NULL);  /* Nope! */
+
+	curgtag = gtag_q.cqh_first;
+	return (curgtag->file);
+}
+
+/*
+ * Return the filename required for the next gtag in the queue that was setup
+ * by findgtag().  The next call to gtagsearch() will try to position at the
+ * appropriate tag.
+ */
+static char *
+nextgtag()
+{
+	if (!curgtag) {
+		/* No tag stack loaded */
+		return (NULL);
+	}
+
+	curgtag = curgtag->ptrs.cqe_next;
+	if (curgtag == (void *)&gtag_q) {
+		/* Wrapped around to the head of the queue */
+		curgtag = ((struct gtag_q *)curgtag)->cqh_first;
+	}
+
+	return (curgtag->file);
+}
+
+/*
+ * Return the filename required for the previous gtag in the queue that was
+ * setup by findgtat().  The next call to gtagsearch() will try to position
+ * at the appropriate tag.
+ */
+static char *
+prevgtag()
+{
+	if (!curgtag) {
+		/* No tag stack loaded */
+		return (NULL);
+	}
+
+	curgtag = curgtag->ptrs.cqe_prev;
+	if (curgtag == (void *)&gtag_q) {
+		/* Wrapped around to the head of the queue */
+		curgtag = ((struct gtag_q *)curgtag)->cqh_last;
+	}
+
+	return (curgtag->file);
+}
+
+/*
+ * Position the current file at at what is hopefully the tag that was chosen
+ * using either findtag() or one of nextgtag() and prevgtag().  Returns -1
+ * if it was unable to position at the tag, 0 if succesful.
+ */
+static
+gtagsearch()
+{
+	if (!curgtag)
+		return (-1);  /* No gtags loaded! */
+
+	jump_back(curgtag->line);
+
+	/*
+	 * XXX We'll assume we were successful --- jump_back() will call error()
+	 * if it fails, so the user will receive some kind of notification.
+	 * Eventually, jump_back() should do its work silently and let us
+	 * perform the error notification, eventually allowing our caller
+	 * (presumably tagsearch()) to go error("Could not locate tag.");
+	 */
+	return (0);
+}
+
+/*
+ * The getentry() parses output from the global(1) command.  The output
+ * must be in the format described below.  Returns 0 on success, -1 on
+ * error.  The tag, file, and line will each be NUL-terminated pointers
+ * into buf.
+ *
+ * gtags temporary file format.
+ * <tag>   <lineno>  <file>         <image>
+ *
+ * sample.
+ * +------------------------------------------------
+ * |main     30      main.c         main(argc, argv)
+ * |func     21      subr.c         func(arg)
+ */
+static
+getentry(buf, tag, file, line)
+	char *buf;	/* output from global -x */
+	char **tag;	/* name of the tag we actually found */
+	char **file;	/* file in which to find this tag */
+	char **line;	/* line number of file where this tag is found */
+{
+	char *p = buf;
+
+	for (*tag = p; *p && !isspace(*p); p++)		/* tag name */
+		;
+	if (*p == 0)
+		goto err;
+	*p++ = 0;
+	for (; *p && isspace(*p); p++)			/* (skip blanks) */
+		;
+	if (*p == 0)
+		goto err;
+	*line = p;					/* line no */
+	for (*line = p; *p && !isspace(*p); p++)
+		;
+	if (*p == 0)
+		goto err;
+	*p++ = 0;
+	for (; *p && isspace(*p); p++)			/* (skip blanks) */
+		;
+	if (*p == 0)
+		goto err;
+	*file = p;					/* file name */
+	for (*file = p; *p && !isspace(*p); p++)
+		;
+	if (*p == 0)
+		goto err;
+	*p = 0;
+
+	/* value check */
+	if (strlen(*tag) && strlen(*line) && strlen(*file) && atoi(*line) > 0)
+		return (0);	/* OK */
+err:
+	return (-1);		/* ERROR */
+}