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-rw-r--r--src/backend/utils/adt/like_match.c333
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diff --git a/src/backend/utils/adt/like_match.c b/src/backend/utils/adt/like_match.c
deleted file mode 100644
index 54ac32dcc53..00000000000
--- a/src/backend/utils/adt/like_match.c
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@@ -1,333 +0,0 @@
-/*-------------------------------------------------------------------------
- *
- * like_match.c
- * like expression handling internal code.
- *
- * This file is included by like.c *twice* if multibyte is enabled.
- * This is for an optimization of single byte encodings.
- * Before the inclusion, we need to define following macros:
- *
- * CHAREQ
- * ICHAREQ
- * NextChar
- * CopyAdvChar
- * MatchText (MBMatchText)
- * MatchTextIC (MBMatchTextIC)
- * do_like_escape (MB_do_like_escape)
- *
- * Copyright (c) 1996-2002, PostgreSQL Global Development Group
- *
- * IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/utils/adt/like_match.c,v 1.3 2002/06/20 20:29:37 momjian Exp $
- *
- *-------------------------------------------------------------------------
- */
-
-/*
-** Originally written by Rich $alz, mirror!rs, Wed Nov 26 19:03:17 EST 1986.
-** Rich $alz is now <rsalz@bbn.com>.
-** Special thanks to Lars Mathiesen <thorinn@diku.dk> for the LABORT code.
-**
-** This code was shamelessly stolen from the "pql" code by myself and
-** slightly modified :)
-**
-** All references to the word "star" were replaced by "percent"
-** All references to the word "wild" were replaced by "like"
-**
-** All the nice shell RE matching stuff was replaced by just "_" and "%"
-**
-** As I don't have a copy of the SQL standard handy I wasn't sure whether
-** to leave in the '\' escape character handling.
-**
-** Keith Parks. <keith@mtcc.demon.co.uk>
-**
-** SQL92 lets you specify the escape character by saying
-** LIKE <pattern> ESCAPE <escape character>. We are a small operation
-** so we force you to use '\'. - ay 7/95
-**
-** Now we have the like_escape() function that converts patterns with
-** any specified escape character (or none at all) to the internal
-** default escape character, which is still '\'. - tgl 9/2000
-**
-** The code is rewritten to avoid requiring null-terminated strings,
-** which in turn allows us to leave out some memcpy() operations.
-** This code should be faster and take less memory, but no promises...
-** - thomas 2000-08-06
-**
-*/
-
-
-/*--------------------
- * Match text and p, return LIKE_TRUE, LIKE_FALSE, or LIKE_ABORT.
- *
- * LIKE_TRUE: they match
- * LIKE_FALSE: they don't match
- * LIKE_ABORT: not only don't they match, but the text is too short.
- *
- * If LIKE_ABORT is returned, then no suffix of the text can match the
- * pattern either, so an upper-level % scan can stop scanning now.
- *--------------------
- */
-
-static int
-MatchText(unsigned char *t, int tlen, unsigned char *p, int plen)
-{
- /* Fast path for match-everything pattern */
- if ((plen == 1) && (*p == '%'))
- return LIKE_TRUE;
-
- while ((tlen > 0) && (plen > 0))
- {
- if (*p == '\\')
- {
- /* Next pattern char must match literally, whatever it is */
- 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 == '\\') || (*p == '_'))
- {
- int matched = MatchText(t, tlen, p, plen);
-
- 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() */
-
-/*
- * Same as above, but ignore case
- */
-static int
-MatchTextIC(unsigned char *t, int tlen, unsigned char *p, int plen)
-{
- /* Fast path for match-everything pattern */
- if ((plen == 1) && (*p == '%'))
- return LIKE_TRUE;
-
- while ((tlen > 0) && (plen > 0))
- {
- if (*p == '\\')
- {
- /* Next pattern char must match literally, whatever it is */
- 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 == '\\') || (*p == '_'))
- {
- int matched = MatchTextIC(t, tlen, p, plen);
-
- 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))
- {
- /*
- * 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;
-} /* MatchTextIC() */
-
-/*
- * like_escape() --- given a pattern and an ESCAPE string,
- * convert the pattern to use Postgres' standard backslash escape convention.
- */
-static text *
-do_like_escape(text *pat, text *esc)
-{
- text *result;
- unsigned char *p,
- *e,
- *r;
- int plen,
- elen;
- bool afterescape;
-
- p = VARDATA(pat);
- plen = (VARSIZE(pat) - VARHDRSZ);
- e = VARDATA(esc);
- elen = (VARSIZE(esc) - VARHDRSZ);
-
- /*
- * Worst-case pattern growth is 2x --- unlikely, but it's hardly worth
- * trying to calculate the size more accurately than that.
- */
- result = (text *) palloc(plen * 2 + VARHDRSZ);
- r = VARDATA(result);
-
- if (elen == 0)
- {
- /*
- * No escape character is wanted. Double any backslashes in the
- * pattern to make them act like ordinary characters.
- */
- while (plen > 0)
- {
- if (*p == '\\')
- *r++ = '\\';
- CopyAdvChar(r, p, plen);
- }
- }
- else
- {
- /*
- * The specified escape must be only a single character.
- */
- NextChar(e, elen);
- if (elen != 0)
- elog(ERROR, "ESCAPE string must be empty or one character");
- e = VARDATA(esc);
-
- /*
- * If specified escape is '\', just copy the pattern as-is.
- */
- if (*e == '\\')
- {
- memcpy(result, pat, VARSIZE(pat));
- return result;
- }
-
- /*
- * Otherwise, convert occurrences of the specified escape
- * character to '\', and double occurrences of '\' --- unless they
- * immediately follow an escape character!
- */
- afterescape = false;
- while (plen > 0)
- {
- if (CHAREQ(p, e) && !afterescape)
- {
- *r++ = '\\';
- NextChar(p, plen);
- afterescape = true;
- }
- else if (*p == '\\')
- {
- *r++ = '\\';
- if (!afterescape)
- *r++ = '\\';
- NextChar(p, plen);
- afterescape = false;
- }
- else
- {
- CopyAdvChar(r, p, plen);
- afterescape = false;
- }
- }
- }
-
- VARATT_SIZEP(result) = r - ((unsigned char *) result);
-
- return result;
-}
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