freebsd-dev/contrib/less/pattern.c
Robert Watson 1ea316270f Currently, less(1) uses K&R prototypes, which both fails to provide useful
compiler-time type checking, and also causes problems for targets where
multiple incompatible calling conventions may be selected based on argument
types.  This change switches less(1) to ANSI prototypes.

While there, we also remove use of "register", and attempt to use "const" a
bit better now that the compiler can check argument types.

Reviewed by:	cem, emaste
MFC after:	3 weeks
Sponsored by:	DARPA, AFRL
Differential Revision:	https://reviews.freebsd.org/D10152
2017-03-31 21:29:43 +00:00

382 lines
7.6 KiB
C

/*
* Copyright (C) 1984-2015 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.
*/
/*
* Routines to do pattern matching.
*/
#include "less.h"
#include "pattern.h"
extern int caseless;
/*
* Compile a search pattern, for future use by match_pattern.
*/
static int
compile_pattern2(char *pattern, int search_type, void **comp_pattern, int show_error)
{
if (search_type & SRCH_NO_REGEX)
return (0);
{
#if HAVE_GNU_REGEX
struct re_pattern_buffer *comp = (struct re_pattern_buffer *)
ecalloc(1, sizeof(struct re_pattern_buffer));
struct re_pattern_buffer **pcomp =
(struct re_pattern_buffer **) comp_pattern;
re_set_syntax(RE_SYNTAX_POSIX_EXTENDED);
if (re_compile_pattern(pattern, strlen(pattern), comp))
{
free(comp);
if (show_error)
error("Invalid pattern", NULL_PARG);
return (-1);
}
if (*pcomp != NULL)
regfree(*pcomp);
*pcomp = comp;
#endif
#if HAVE_POSIX_REGCOMP
regex_t *comp = (regex_t *) ecalloc(1, sizeof(regex_t));
regex_t **pcomp = (regex_t **) comp_pattern;
if (regcomp(comp, pattern, REGCOMP_FLAG))
{
free(comp);
if (show_error)
error("Invalid pattern", NULL_PARG);
return (-1);
}
if (*pcomp != NULL)
regfree(*pcomp);
*pcomp = comp;
#endif
#if HAVE_PCRE
pcre *comp;
pcre **pcomp = (pcre **) comp_pattern;
constant char *errstring;
int erroffset;
PARG parg;
comp = pcre_compile(pattern, 0,
&errstring, &erroffset, NULL);
if (comp == NULL)
{
parg.p_string = (char *) errstring;
if (show_error)
error("%s", &parg);
return (-1);
}
*pcomp = comp;
#endif
#if HAVE_RE_COMP
PARG parg;
int *pcomp = (int *) comp_pattern;
if ((parg.p_string = re_comp(pattern)) != NULL)
{
if (show_error)
error("%s", &parg);
return (-1);
}
*pcomp = 1;
#endif
#if HAVE_REGCMP
char *comp;
char **pcomp = (char **) comp_pattern;
if ((comp = regcmp(pattern, 0)) == NULL)
{
if (show_error)
error("Invalid pattern", NULL_PARG);
return (-1);
}
if (pcomp != NULL)
free(*pcomp);
*pcomp = comp;
#endif
#if HAVE_V8_REGCOMP
struct regexp *comp;
struct regexp **pcomp = (struct regexp **) comp_pattern;
reg_show_error = show_error;
comp = regcomp(pattern);
reg_show_error = 1;
if (comp == NULL)
{
/*
* regcomp has already printed an error message
* via regerror().
*/
return (-1);
}
if (*pcomp != NULL)
free(*pcomp);
*pcomp = comp;
#endif
}
return (0);
}
/*
* Like compile_pattern2, but convert the pattern to lowercase if necessary.
*/
public int
compile_pattern(char *pattern, int search_type, void **comp_pattern)
{
char *cvt_pattern;
int result;
if (caseless != OPT_ONPLUS)
cvt_pattern = pattern;
else
{
cvt_pattern = (char*) ecalloc(1, cvt_length(strlen(pattern), CVT_TO_LC));
cvt_text(cvt_pattern, pattern, (int *)NULL, (int *)NULL, CVT_TO_LC);
}
result = compile_pattern2(cvt_pattern, search_type, comp_pattern, 1);
if (cvt_pattern != pattern)
free(cvt_pattern);
return (result);
}
/*
* Forget that we have a compiled pattern.
*/
public void
uncompile_pattern(void **pattern)
{
#if HAVE_GNU_REGEX
struct re_pattern_buffer **pcomp = (struct re_pattern_buffer **) pattern;
if (*pcomp != NULL)
regfree(*pcomp);
*pcomp = NULL;
#endif
#if HAVE_POSIX_REGCOMP
regex_t **pcomp = (regex_t **) pattern;
if (*pcomp != NULL)
regfree(*pcomp);
*pcomp = NULL;
#endif
#if HAVE_PCRE
pcre **pcomp = (pcre **) pattern;
if (*pcomp != NULL)
pcre_free(*pcomp);
*pcomp = NULL;
#endif
#if HAVE_RE_COMP
int *pcomp = (int *) pattern;
*pcomp = 0;
#endif
#if HAVE_REGCMP
char **pcomp = (char **) pattern;
if (*pcomp != NULL)
free(*pcomp);
*pcomp = NULL;
#endif
#if HAVE_V8_REGCOMP
struct regexp **pcomp = (struct regexp **) pattern;
if (*pcomp != NULL)
free(*pcomp);
*pcomp = NULL;
#endif
}
/*
* Can a pattern be successfully compiled?
*/
public int
valid_pattern(char *pattern)
{
void *comp_pattern;
int result;
CLEAR_PATTERN(comp_pattern);
result = compile_pattern2(pattern, 0, &comp_pattern, 0);
if (result != 0)
return (0);
uncompile_pattern(&comp_pattern);
return (1);
}
/*
* Is a compiled pattern null?
*/
public int
is_null_pattern(void *pattern)
{
#if HAVE_GNU_REGEX
return (pattern == NULL);
#endif
#if HAVE_POSIX_REGCOMP
return (pattern == NULL);
#endif
#if HAVE_PCRE
return (pattern == NULL);
#endif
#if HAVE_RE_COMP
return (pattern == 0);
#endif
#if HAVE_REGCMP
return (pattern == NULL);
#endif
#if HAVE_V8_REGCOMP
return (pattern == NULL);
#endif
#if NO_REGEX
return (pattern == NULL);
#endif
}
/*
* Simple pattern matching function.
* It supports no metacharacters like *, etc.
*/
static int
match(char *pattern, int pattern_len, char *buf, int buf_len, char **pfound, char **pend)
{
char *pp, *lp;
char *pattern_end = pattern + pattern_len;
char *buf_end = buf + buf_len;
for ( ; buf < buf_end; buf++)
{
for (pp = pattern, lp = buf; ; pp++, lp++)
{
char cp = *pp;
char cl = *lp;
if (caseless == OPT_ONPLUS && ASCII_IS_UPPER(cp))
cp = ASCII_TO_LOWER(cp);
if (cp != cl)
break;
if (pp == pattern_end || lp == buf_end)
break;
}
if (pp == pattern_end)
{
if (pfound != NULL)
*pfound = buf;
if (pend != NULL)
*pend = lp;
return (1);
}
}
return (0);
}
/*
* Perform a pattern match with the previously compiled pattern.
* Set sp and ep to the start and end of the matched string.
*/
public int
match_pattern(void *pattern, char *tpattern, char *line, int line_len, char **sp, char **ep, int notbol, int search_type)
{
int matched;
#if HAVE_GNU_REGEX
struct re_pattern_buffer *spattern = (struct re_pattern_buffer *) pattern;
#endif
#if HAVE_POSIX_REGCOMP
regex_t *spattern = (regex_t *) pattern;
#endif
#if HAVE_PCRE
pcre *spattern = (pcre *) pattern;
#endif
#if HAVE_RE_COMP
int spattern = (int) pattern;
#endif
#if HAVE_REGCMP
char *spattern = (char *) pattern;
#endif
#if HAVE_V8_REGCOMP
struct regexp *spattern = (struct regexp *) pattern;
#endif
*sp = *ep = NULL;
#if NO_REGEX
search_type |= SRCH_NO_REGEX;
#endif
if (search_type & SRCH_NO_REGEX)
matched = match(tpattern, strlen(tpattern), line, line_len, sp, ep);
else
{
#if HAVE_GNU_REGEX
{
struct re_registers search_regs;
spattern->not_bol = notbol;
spattern->regs_allocated = REGS_UNALLOCATED;
matched = re_search(spattern, line, line_len, 0, line_len, &search_regs) >= 0;
if (matched)
{
*sp = line + search_regs.start[0];
*ep = line + search_regs.end[0];
}
}
#endif
#if HAVE_POSIX_REGCOMP
{
regmatch_t rm;
int flags = (notbol) ? REG_NOTBOL : 0;
#ifdef REG_STARTEND
flags |= REG_STARTEND;
rm.rm_so = 0;
rm.rm_eo = line_len;
#endif
matched = !regexec(spattern, line, 1, &rm, flags);
if (matched)
{
#ifndef __WATCOMC__
*sp = line + rm.rm_so;
*ep = line + rm.rm_eo;
#else
*sp = rm.rm_sp;
*ep = rm.rm_ep;
#endif
}
}
#endif
#if HAVE_PCRE
{
int flags = (notbol) ? PCRE_NOTBOL : 0;
int ovector[3];
matched = pcre_exec(spattern, NULL, line, line_len,
0, flags, ovector, 3) >= 0;
if (matched)
{
*sp = line + ovector[0];
*ep = line + ovector[1];
}
}
#endif
#if HAVE_RE_COMP
matched = (re_exec(line) == 1);
/*
* re_exec doesn't seem to provide a way to get the matched string.
*/
*sp = *ep = NULL;
#endif
#if HAVE_REGCMP
*ep = regex(spattern, line);
matched = (*ep != NULL);
if (matched)
*sp = __loc1;
#endif
#if HAVE_V8_REGCOMP
#if HAVE_REGEXEC2
matched = regexec2(spattern, line, notbol);
#else
matched = regexec(spattern, line);
#endif
if (matched)
{
*sp = spattern->startp[0];
*ep = spattern->endp[0];
}
#endif
}
matched = (!(search_type & SRCH_NO_MATCH) && matched) ||
((search_type & SRCH_NO_MATCH) && !matched);
return (matched);
}