125 lines
3.8 KiB
C
125 lines
3.8 KiB
C
/* $XConsortium: wildmat.c,v 1.2 94/04/13 18:40:59 rws Exp $ */
|
|
/*
|
|
**
|
|
** Do shell-style pattern matching for ?, \, [], and * characters.
|
|
** Might not be robust in face of malformed patterns; e.g., "foo[a-"
|
|
** could cause a segmentation violation. It is 8bit clean.
|
|
**
|
|
** Written by Rich $alz, mirror!rs, Wed Nov 26 19:03:17 EST 1986.
|
|
** Rich $alz is now <rsalz@bbn.com>.
|
|
** April, 1991: Replaced mutually-recursive calls with in-line code
|
|
** for the star character.
|
|
**
|
|
** Special thanks to Lars Mathiesen <thorinn@diku.dk> for the ABORT code.
|
|
** This can greatly speed up failing wildcard patterns. For example:
|
|
** pattern: -*-*-*-*-*-*-12-*-*-*-m-*-*-*
|
|
** text 1: -adobe-courier-bold-o-normal--12-120-75-75-m-70-iso8859-1
|
|
** text 2: -adobe-courier-bold-o-normal--12-120-75-75-X-70-iso8859-1
|
|
** Text 1 matches with 51 calls, while text 2 fails with 54 calls. Without
|
|
** the ABORT, then it takes 22310 calls to fail. Ugh. The following
|
|
** explanation is from Lars:
|
|
** The precondition that must be fulfilled is that DoMatch will consume
|
|
** at least one character in text. This is true if *p is neither '*' nor
|
|
** '\0'.) The last return has ABORT instead of FALSE to avoid quadratic
|
|
** behaviour in cases like pattern "*a*b*c*d" with text "abcxxxxx". With
|
|
** FALSE, each star-loop has to run to the end of the text; with ABORT
|
|
** only the last one does.
|
|
**
|
|
** Once the control of one instance of DoMatch enters the star-loop, that
|
|
** instance will return either TRUE or ABORT, and any calling instance
|
|
** will therefore return immediately after (without calling recursively
|
|
** again). In effect, only one star-loop is ever active. It would be
|
|
** possible to modify the code to maintain this context explicitly,
|
|
** eliminating all recursive calls at the cost of some complication and
|
|
** loss of clarity (and the ABORT stuff seems to be unclear enough by
|
|
** itself). I think it would be unwise to try to get this into a
|
|
** released version unless you have a good test data base to try it out
|
|
** on.
|
|
*/
|
|
|
|
#include "utils.h"
|
|
|
|
#define TRUE 1
|
|
#define FALSE 0
|
|
#define ABORT -1
|
|
|
|
|
|
/* What character marks an inverted character class? */
|
|
#define NEGATE_CLASS '^'
|
|
/* Is "*" a common pattern? */
|
|
#define OPTIMIZE_JUST_STAR
|
|
/* Do tar(1) matching rules, which ignore a trailing slash? */
|
|
#undef MATCH_TAR_PATTERN
|
|
|
|
|
|
/*
|
|
** Match text and p, return TRUE, FALSE, or ABORT.
|
|
*/
|
|
static int
|
|
DoMatch( const char * text, const char * p )
|
|
{
|
|
register int last;
|
|
register int matched;
|
|
register int reverse;
|
|
|
|
for ( ; *p; text++, p++) {
|
|
if (*text == '\0' && *p != '*')
|
|
return ABORT;
|
|
switch (*p) {
|
|
case '\\':
|
|
/* Literal match with following character. */
|
|
p++;
|
|
/* FALLTHROUGH */
|
|
default:
|
|
if (*text != *p)
|
|
return FALSE;
|
|
continue;
|
|
case '?':
|
|
/* Match anything. */
|
|
continue;
|
|
case '*':
|
|
while (*++p == '*')
|
|
/* Consecutive stars act just like one. */
|
|
continue;
|
|
if (*p == '\0')
|
|
/* Trailing star matches everything. */
|
|
return TRUE;
|
|
while (*text)
|
|
if ((matched = DoMatch(text++, p)) != FALSE)
|
|
return matched;
|
|
return ABORT;
|
|
case '[':
|
|
reverse = p[1] == NEGATE_CLASS ? TRUE : FALSE;
|
|
if (reverse)
|
|
/* Inverted character class. */
|
|
p++;
|
|
for (last = 0400, matched = FALSE; *++p && *p != ']'; last = *p)
|
|
/* This next line requires a good C compiler. */
|
|
if (*p == '-' ? *text <= *++p && *text >= last : *text == *p)
|
|
matched = TRUE;
|
|
if (matched == reverse)
|
|
return FALSE;
|
|
continue;
|
|
}
|
|
}
|
|
|
|
#ifdef MATCH_TAR_PATTERN
|
|
if (*text == '/')
|
|
return TRUE;
|
|
#endif /* MATCH_TAR_ATTERN */
|
|
return *text == '\0';
|
|
}
|
|
|
|
|
|
/*
|
|
** User-level routine. Returns TRUE or FALSE.
|
|
*/
|
|
int
|
|
tr_wildmat(const char * text, const char * p )
|
|
{
|
|
if (p[0] == '*' && p[1] == '\0')
|
|
return TRUE;
|
|
|
|
return DoMatch(text, p) == TRUE;
|
|
}
|