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#include "postgres_fe.h"
#include <ctype.h>
#include "mb/pg_wchar.h"
#define LIKE_FALSE 0
#define LIKE_TRUE 1
#define LIKE_ABORT 2
#define PG_CHAR unsigned char
#define UCHARMAX 0xff
/*----------------------------------------------------------------*/
static int wchareq(unsigned char *p1, unsigned char *p2)
{
int l;
l = pg_mblen(p1);
if (pg_mblen(p2) != l) {
return(0);
}
while (l--) {
if (*p1++ != *p2++)
return(0);
}
return(1);
}
static int iwchareq(unsigned char *p1, unsigned char *p2)
{
int c1, c2;
int l;
/* short cut. if *p1 and *p2 is lower than UCHARMAX, then
we assume they are ASCII */
if (*p1 < UCHARMAX && *p2 < UCHARMAX)
return(tolower(*p1) == tolower(*p2));
if (*p1 < UCHARMAX)
c1 = tolower(*p1);
else
{
l = pg_mblen(p1);
(void)pg_mb2wchar_with_len(p1, (pg_wchar *)&c1, l);
c1 = tolower(c1);
}
if (*p2 < UCHARMAX)
c2 = tolower(*p2);
else
{
l = pg_mblen(p2);
(void)pg_mb2wchar_with_len(p2, (pg_wchar *)&c2, l);
c2 = tolower(c2);
}
return(c1 == c2);
}
#ifdef MULTIBYTE
#define CHAREQ(p1, p2) wchareq(p1, p2)
#define ICHAREQ(p1, p2) iwchareq(p1, p2)
#define NextChar(p, plen) {int __l = pg_mblen(p); (p) +=__l; (plen) -=__l;}
#else
#define CHAREQ(p1, p2) (*(p1) == *(p2))
#define ICHAREQ(p1, p2) (tolower(*(p1)) == tolower(*(p2)))
#define NextChar(p, plen) (p)++, (plen)--
#endif
static int
MatchText(PG_CHAR * t, int tlen, PG_CHAR * p, int plen, char *e)
{
/* Fast path for match-everything pattern
* Include weird case of escape character as a percent sign or underscore,
* when presumably that wildcard character becomes a literal.
*/
if ((plen == 1) && (*p == '%')
&& ! ((e != NULL) && (*e == '%')))
return LIKE_TRUE;
while ((tlen > 0) && (plen > 0))
{
/* If an escape character was specified and we find it here in the pattern,
* then we'd better have an exact match for the next character.
*/
if ((e != NULL) && CHAREQ(p,e))
{
NextChar(p, plen);
if ((plen <= 0) || !CHAREQ(t,p))
return LIKE_FALSE;
}
else if (*p == '%')
{
/* %% is the same as % according to the SQL standard */
/* Advance past all %'s */
while ((plen > 0) && (*p == '%'))
NextChar(p, plen);
/* Trailing percent matches everything. */
if (plen <= 0)
return LIKE_TRUE;
/*
* Otherwise, scan for a text position at which we can
* match the rest of the pattern.
*/
while (tlen > 0)
{
/*
* Optimization to prevent most recursion: don't
* recurse unless first pattern char might match this
* text char.
*/
if (CHAREQ(t,p) || (*p == '_')
|| ((e != NULL) && CHAREQ(p,e)))
{
int matched = MatchText(t, tlen, p, plen, e);
if (matched != LIKE_FALSE)
return matched; /* TRUE or ABORT */
}
NextChar(t, tlen);
}
/*
* End of text with no match, so no point in trying later
* places to start matching this pattern.
*/
return LIKE_ABORT;
}
else if ((*p != '_') && !CHAREQ(t,p))
{
/* Not the single-character wildcard and no explicit match?
* Then time to quit...
*/
return LIKE_FALSE;
}
NextChar(t, tlen);
NextChar(p, plen);
}
if (tlen > 0)
return LIKE_FALSE; /* end of pattern, but not of text */
/* End of input string. Do we have matching pattern remaining? */
while ((plen > 0) && (*p == '%')) /* allow multiple %'s at end of pattern */
NextChar(p, plen);
if (plen <= 0)
return LIKE_TRUE;
/*
* End of text with no match, so no point in trying later places to
* start matching this pattern.
*/
return LIKE_ABORT;
} /* MatchText() */
static int
MatchTextLower(PG_CHAR * t, int tlen, PG_CHAR * p, int plen, char *e)
{
/* Fast path for match-everything pattern
* Include weird case of escape character as a percent sign or underscore,
* when presumably that wildcard character becomes a literal.
*/
if ((plen == 1) && (*p == '%')
&& ! ((e != NULL) && (*e == '%')))
return LIKE_TRUE;
while ((tlen > 0) && (plen > 0))
{
/* If an escape character was specified and we find it here in the pattern,
* then we'd better have an exact match for the next character.
*/
if ((e != NULL) && ICHAREQ(p,e))
{
NextChar(p, plen);
if ((plen <= 0) || !ICHAREQ(t,p))
return LIKE_FALSE;
}
else if (*p == '%')
{
/* %% is the same as % according to the SQL standard */
/* Advance past all %'s */
while ((plen > 0) && (*p == '%'))
NextChar(p, plen);
/* Trailing percent matches everything. */
if (plen <= 0)
return LIKE_TRUE;
/*
* Otherwise, scan for a text position at which we can
* match the rest of the pattern.
*/
while (tlen > 0)
{
/*
* Optimization to prevent most recursion: don't
* recurse unless first pattern char might match this
* text char.
*/
if (ICHAREQ(t,p) || (*p == '_')
|| ((e != NULL) && ICHAREQ(p,e)))
{
int matched = MatchText(t, tlen, p, plen, e);
if (matched != LIKE_FALSE)
return matched; /* TRUE or ABORT */
}
NextChar(t, tlen);
}
/*
* End of text with no match, so no point in trying later
* places to start matching this pattern.
*/
return LIKE_ABORT;
}
else if ((*p != '_') && !ICHAREQ(t,p))
{
return LIKE_FALSE;
}
NextChar(t, tlen);
NextChar(p, plen);
}
if (tlen > 0)
return LIKE_FALSE; /* end of pattern, but not of text */
/* End of input string. Do we have matching pattern remaining? */
while ((plen > 0) && (*p == '%')) /* allow multiple %'s at end of pattern */
NextChar(p, plen);
if (plen <= 0)
return LIKE_TRUE;
/*
* End of text with no match, so no point in trying later places to
* start matching this pattern.
*/
return LIKE_ABORT;
} /* MatchTextLower() */
main()
{
unsigned char *t = "��Z01��";
unsigned char *p = "_Z%";
int tlen, plen;
tlen = strlen(t);
plen = strlen(p);
printf("%d\n",MatchTextLower(t,tlen,p,plen,"\\"));
}
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