/*
* Copyright (C) 1984-2017 Mark Nudelman
*
* You may distribute under the terms of either the GNU General Public
* License or the Less License, as specified in the README file.
*
* For more information, see the README file.
*/
#include "less.h"
#define WHITESP(c) ((c)==' ' || (c)=='\t')
#if TAGS
public char ztags[] = "tags";
public char *tags = ztags;
static int total;
static int curseq;
extern int linenums;
extern int sigs;
extern int ctldisp;
enum tag_result {
TAG_FOUND,
TAG_NOFILE,
TAG_NOTAG,
TAG_NOTYPE,
TAG_INTR
};
/*
* Tag type
*/
enum {
T_CTAGS, /* 'tags': standard and extended format (ctags) */
T_CTAGS_X, /* stdin: cross reference format (ctags) */
T_GTAGS, /* 'GTAGS': function defenition (global) */
T_GRTAGS, /* 'GRTAGS': function reference (global) */
T_GSYMS, /* 'GSYMS': other symbols (global) */
T_GPATH /* 'GPATH': path name (global) */
};
static enum tag_result findctag();
static enum tag_result findgtag();
static char *nextgtag();
static char *prevgtag();
static POSITION ctagsearch();
static POSITION gtagsearch();
static int getentry();
/*
* The list of tags generated by the last findgtag() call.
*
* Use either pattern or line number.
* findgtag() always uses line number, so pattern is always NULL.
* findctag() uses either pattern (in which case line number is 0),
* or line number (in which case pattern is NULL).
*/
struct taglist {
struct tag *tl_first;
struct tag *tl_last;
};
struct tag {
struct tag *next, *prev; /* List links */
char *tag_file; /* Source file containing the tag */
LINENUM tag_linenum; /* Appropriate line number in source file */
char *tag_pattern; /* Pattern used to find the tag */
char tag_endline; /* True if the pattern includes '$' */
};
#define TAG_END ((struct tag *) &taglist)
static struct taglist taglist = { TAG_END, TAG_END };
static struct tag *curtag;
#define TAG_INS(tp) \
(tp)->next = TAG_END; \
(tp)->prev = taglist.tl_last; \
taglist.tl_last->next = (tp); \
taglist.tl_last = (tp);
#define TAG_RM(tp) \
(tp)->next->prev = (tp)->prev; \
(tp)->prev->next = (tp)->next;
/*
* Delete tag structures.
*/
public void
cleantags()
{
struct tag *tp;
/*
* Delete any existing tag list.
* {{ Ideally, we wouldn't do this until after we know that we
* can load some other tag information. }}
*/
while ((tp = taglist.tl_first) != TAG_END)
{
TAG_RM(tp);
free(tp->tag_file);
free(tp->tag_pattern);
free(tp);
}
curtag = NULL;
total = curseq = 0;
}
/*
* Create a new tag entry.
*/
static struct tag *
maketagent(name, file, linenum, pattern, endline)
char *name;
char *file;
LINENUM linenum;
char *pattern;
int endline;
{
struct tag *tp;
tp = (struct tag *) ecalloc(sizeof(struct tag), 1);
tp->tag_file = (char *) ecalloc(strlen(file) + 1, sizeof(char));
strcpy(tp->tag_file, file);
tp->tag_linenum = linenum;
tp->tag_endline = endline;
if (pattern == NULL)
tp->tag_pattern = NULL;
else
{
tp->tag_pattern = (char *) ecalloc(strlen(pattern) + 1, sizeof(char));
strcpy(tp->tag_pattern, pattern);
}
return (tp);
}
/*
* Get tag mode.
*/
public int
gettagtype()
{
int f;
if (strcmp(tags, "GTAGS") == 0)
return T_GTAGS;
if (strcmp(tags, "GRTAGS") == 0)
return T_GRTAGS;
if (strcmp(tags, "GSYMS") == 0)
return T_GSYMS;
if (strcmp(tags, "GPATH") == 0)
return T_GPATH;
if (strcmp(tags, "-") == 0)
return T_CTAGS_X;
f = open(tags, OPEN_READ);
if (f >= 0)
{
close(f);
return T_CTAGS;
}
return T_GTAGS;
}
/*
* Find tags in tag file.
* Find a tag in the "tags" file.
* Sets "tag_file" to the name of the file containing the tag,
* and "tagpattern" to the search pattern which should be used
* to find the tag.
*/
public void
findtag(tag)
char *tag;
{
int type = gettagtype();
enum tag_result result;
if (type == T_CTAGS)
result = findctag(tag);
else
result = findgtag(tag, type);
switch (result)
{
case TAG_FOUND:
case TAG_INTR:
break;
case TAG_NOFILE:
error("No tags file", NULL_PARG);
break;
case TAG_NOTAG:
error("No such tag in tags file", NULL_PARG);
break;
case TAG_NOTYPE:
error("unknown tag type", NULL_PARG);
break;
}
}
/*
* Search for a tag.
*/
public POSITION
tagsearch()
{
if (curtag == NULL)
return (NULL_POSITION); /* No gtags loaded! */
if (curtag->tag_linenum != 0)
return gtagsearch();
else
return ctagsearch();
}
/*
* Go to the next tag.
*/
public char *
nexttag(n)
int n;
{
char *tagfile = (char *) NULL;
while (n-- > 0)
tagfile = nextgtag();
return tagfile;
}
/*
* Go to the previous tag.
*/
public char *
prevtag(n)
int n;
{
char *tagfile = (char *) NULL;
while (n-- > 0)
tagfile = prevgtag();
return tagfile;
}
/*
* Return the total number of tags.
*/
public int
ntags()
{
return total;
}
/*
* Return the sequence number of current tag.
*/
public int
curr_tag()
{
return curseq;
}
/*****************************************************************************
* ctags
*/
/*
* Find tags in the "tags" file.
* Sets curtag to the first tag entry.
*/
static enum tag_result
findctag(tag)
char *tag;
{
char *p;
FILE *f;
int taglen;
LINENUM taglinenum;
char *tagfile;
char *tagpattern;
int tagendline;
int search_char;
int err;
char tline[TAGLINE_SIZE];
struct tag *tp;
p = shell_unquote(tags);
f = fopen(p, "r");
free(p);
if (f == NULL)
return TAG_NOFILE;
cleantags();
total = 0;
taglen = (int) strlen(tag);
/*
* Search the tags file for the desired tag.
*/
while (fgets(tline, sizeof(tline), f) != NULL)
{
if (tline[0] == '!')
/* Skip header of extended format. */
continue;
if (strncmp(tag, tline, taglen) != 0 || !WHITESP(tline[taglen]))
continue;
/*
* Found it.
* The line contains the tag, the filename and the
* location in the file, separated by white space.
* The location is either a decimal line number,
* or a search pattern surrounded by a pair of delimiters.
* Parse the line and extract these parts.
*/
tagpattern = NULL;
/*
* Skip over the whitespace after the tag name.
*/
p = skipsp(tline+taglen);
if (*p == '\0')
/* File name is missing! */
continue;
/*
* Save the file name.
* Skip over the whitespace after the file name.
*/
tagfile = p;
while (!WHITESP(*p) && *p != '\0')
p++;
*p++ = '\0';
p = skipsp(p);
if (*p == '\0')
/* Pattern is missing! */
continue;
/*
* First see if it is a line number.
*/
tagendline = 0;
taglinenum = getnum(&p, 0, &err);
if (err)
{
/*
* No, it must be a pattern.
* Delete the initial "^" (if present) and
* the final "$" from the pattern.
* Delete any backslash in the pattern.
*/
taglinenum = 0;
search_char = *p++;
if (*p == '^')
p++;
tagpattern = p;
while (*p != search_char && *p != '\0')
{
if (*p == '\\')
p++;
p++;
}
tagendline = (p[-1] == '$');
if (tagendline)
p--;
*p = '\0';
}
tp = maketagent(tag, tagfile, taglinenum, tagpattern, tagendline);
TAG_INS(tp);
total++;
}
fclose(f);
if (total == 0)
return TAG_NOTAG;
curtag = taglist.tl_first;
curseq = 1;
return TAG_FOUND;
}
/*
* Edit current tagged file.
*/
public int
edit_tagfile()
{
if (curtag == NULL)
return (1);
return (edit(curtag->tag_file));
}
static int
curtag_match(char const *line, POSITION linepos)
{
/*
* Test the line to see if we have a match.
* Use strncmp because the pattern may be
* truncated (in the tags file) if it is too long.
* If tagendline is set, make sure we match all
* the way to end of line (no extra chars after the match).
*/
int len = (int) strlen(curtag->tag_pattern);
if (strncmp(curtag->tag_pattern, line, len) == 0 &&
(!curtag->tag_endline || line[len] == '\0' || line[len] == '\r'))
{
curtag->tag_linenum = find_linenum(linepos);
return 1;
}
return 0;
}
/*
* Search for a tag.
* 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).
*/
static POSITION
ctagsearch()
{
POSITION pos, linepos;
LINENUM linenum;
int line_len;
char *line;
int found;
pos = ch_zero();
linenum = find_linenum(pos);
for (found = 0; !found;)
{
/*
* Get lines until we find a matching one or
* until we hit end-of-file.
*/
if (ABORT_SIGS())
return (NULL_POSITION);
/*
* Read the next line, and save the
* starting position of that line in linepos.
*/
linepos = pos;
pos = forw_raw_line(pos, &line, &line_len);
if (linenum != 0)
linenum++;
if (pos == NULL_POSITION)
{
/*
* We hit EOF without a match.
*/
error("Tag not found", NULL_PARG);
return (NULL_POSITION);
}
/*
* If we're using line numbers, we might as well
* remember the information we have now (the position
* and line number of the current line).
*/
if (linenums)
add_lnum(linenum, pos);
if (ctldisp != OPT_ONPLUS)
{
if (curtag_match(line, linepos))
found = 1;
} else
{
int cvt_ops = CVT_ANSI;
int cvt_len = cvt_length(line_len, cvt_ops);
int *chpos = cvt_alloc_chpos(cvt_len);
char *cline = (char *) ecalloc(1, cvt_len);
cvt_text(cline, line, chpos, &line_len, cvt_ops);
if (curtag_match(cline, linepos))
found = 1;
free(chpos);
free(cline);
}
}
return (linepos);
}
/*******************************************************************************
* gtags
*/
/*
* Find tags in the GLOBAL's tag file.
* The findgtag() will try and load information about the requested tag.
* It does this by calling "global -x tag" and storing the parsed output
* for future use by gtagsearch().
* Sets curtag to the first tag entry.
*/
static enum tag_result
findgtag(tag, type)
char *tag; /* tag to load */
int type; /* tags type */
{
char buf[256];
FILE *fp;
struct tag *tp;
if (type != T_CTAGS_X && tag == NULL)
return TAG_NOFILE;
cleantags();
total = 0;
/*
* If type == T_CTAGS_X then read ctags's -x format from stdin
* else execute global(1) and read from it.
*/
if (type == T_CTAGS_X)
{
fp = stdin;
/* Set tag default because we cannot read stdin again. */
tags = ztags;
} else
{
#if !HAVE_POPEN
return TAG_NOFILE;
#else
char *command;
char *flag;
char *qtag;
char *cmd = lgetenv("LESSGLOBALTAGS");
if (cmd == NULL || *cmd == '\0')
return TAG_NOFILE;
/* Get suitable flag value for global(1). */
switch (type)
{
case T_GTAGS:
flag = "" ;
break;
case T_GRTAGS:
flag = "r";
break;
case T_GSYMS:
flag = "s";
break;
case T_GPATH:
flag = "P";
break;
default:
return TAG_NOTYPE;
}
/* Get our data from global(1). */
qtag = shell_quote(tag);
if (qtag == NULL)
qtag = tag;
command = (char *) ecalloc(strlen(cmd) + strlen(flag) +
strlen(qtag) + 5, sizeof(char));
sprintf(command, "%s -x%s %s", cmd, flag, qtag);
if (qtag != tag)
free(qtag);
fp = popen(command, "r");
free(command);
#endif
}
if (fp != NULL)
{
while (fgets(buf, sizeof(buf), fp))
{
char *name, *file, *line;
int len;
if (sigs)
{
#if HAVE_POPEN
if (fp != stdin)
pclose(fp);
#endif
return TAG_INTR;
}
len = (int) strlen(buf);
if (len > 0 && buf[len-1] == '\n')
buf[len-1] = '\0';
else
{
int c;
do {
c = fgetc(fp);
} while (c != '\n' && c != EOF);
}
if (getentry(buf, &name, &file, &line))
{
/*
* Couldn't parse this line for some reason.
* We'll just pretend it never happened.
*/
break;
}
/* Make new entry and add to list. */
tp = maketagent(name, file, (LINENUM) atoi(line), NULL, 0);
TAG_INS(tp);
total++;
}
if (fp != stdin)
{
if (pclose(fp))
{
curtag = NULL;
total = curseq = 0;
return TAG_NOFILE;
}
}
}
/* Check to see if we found anything. */
tp = taglist.tl_first;
if (tp == TAG_END)
return TAG_NOTAG;
curtag = tp;
curseq = 1;
return TAG_FOUND;
}
static int circular = 0; /* 1: circular tag structure */
/*
* 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()
{
struct tag *tp;
if (curtag == NULL)
/* No tag loaded */
return NULL;
tp = curtag->next;
if (tp == TAG_END)
{
if (!circular)
return NULL;
/* Wrapped around to the head of the queue */
curtag = taglist.tl_first;
curseq = 1;
} else
{
curtag = tp;
curseq++;
}
return (curtag->tag_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()
{
struct tag *tp;
if (curtag == NULL)
/* No tag loaded */
return NULL;
tp = curtag->prev;
if (tp == TAG_END)
{
if (!circular)
return NULL;
/* Wrapped around to the tail of the queue */
curtag = taglist.tl_last;
curseq = total;
} else
{
curtag = tp;
curseq--;
}
return (curtag->tag_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 successful.
*/
static POSITION
gtagsearch()
{
if (curtag == NULL)
return (NULL_POSITION); /* No gtags loaded! */
return (find_pos(curtag->tag_linenum));
}
/*
* The getentry() parses both standard and extended ctags -x format.
*
* [standard format]
* <tag> <lineno> <file> <image>
* +------------------------------------------------
* |main 30 main.c main(argc, argv)
* |func 21 subr.c func(arg)
*
* The following commands write this format.
* o Traditinal Ctags with -x option
* o Global with -x option
* See <http://www.gnu.org/software/global/global.html>
*
* [extended format]
* <tag> <type> <lineno> <file> <image>
* +----------------------------------------------------------
* |main function 30 main.c main(argc, argv)
* |func function 21 subr.c func(arg)
*
* The following commands write this format.
* o Exuberant Ctags with -x option
* See <http://ctags.sourceforge.net>
*
* Returns 0 on success, -1 on error.
* The tag, file, and line will each be NUL-terminated pointers
* into buf.
*/
static int
getentry(buf, tag, file, line)
char *buf; /* standard or extended ctags -x format data */
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 && !IS_SPACE(*p); p++) /* tag name */
;
if (*p == 0)
return (-1);
*p++ = 0;
for ( ; *p && IS_SPACE(*p); p++) /* (skip blanks) */
;
if (*p == 0)
return (-1);
/*
* If the second part begin with other than digit,
* it is assumed tag type. Skip it.
*/
if (!IS_DIGIT(*p))
{
for ( ; *p && !IS_SPACE(*p); p++) /* (skip tag type) */
;
for (; *p && IS_SPACE(*p); p++) /* (skip blanks) */
;
}
if (!IS_DIGIT(*p))
return (-1);
*line = p; /* line number */
for (*line = p; *p && !IS_SPACE(*p); p++)
;
if (*p == 0)
return (-1);
*p++ = 0;
for ( ; *p && IS_SPACE(*p); p++) /* (skip blanks) */
;
if (*p == 0)
return (-1);
*file = p; /* file name */
for (*file = p; *p && !IS_SPACE(*p); p++)
;
if (*p == 0)
return (-1);
*p = 0;
/* value check */
if (strlen(*tag) && strlen(*line) && strlen(*file) && atoi(*line) > 0)
return (0);
return (-1);
}
#endif