示例#1
0
/*
 * RE_wchar_execute - execute a RE on pg_wchar data
 *
 * Returns TRUE on match, FALSE on no match
 *
 *	re --- the compiled pattern as returned by RE_compile_and_cache
 *	data --- the data to match against (need not be null-terminated)
 *	data_len --- the length of the data string
 *	start_search -- the offset in the data to start searching
 *	nmatch, pmatch	--- optional return area for match details
 *
 * Data is given as array of pg_wchar which is what Spencer's regex package
 * wants.
 */
static bool
RE_wchar_execute(regex_t *re, pg_wchar *data, int data_len,
				 int start_search, int nmatch, regmatch_t *pmatch)
{
	int			regexec_result;
	char		errMsg[100];

	/* Perform RE match and return result */
	regexec_result = pg_regexec(re,
								data,
								data_len,
								start_search,
								NULL,	/* no details */
								nmatch,
								pmatch,
								0);

	if (regexec_result != REG_OKAY && regexec_result != REG_NOMATCH)
	{
		/* re failed??? */
		CHECK_FOR_INTERRUPTS();
		pg_regerror(regexec_result, re, errMsg, sizeof(errMsg));
		ereport(ERROR,
				(errcode(ERRCODE_INVALID_REGULAR_EXPRESSION),
				 errmsg("regular expression failed: %s", errMsg)));
	}

	return (regexec_result == REG_OKAY);
}
示例#2
0
/*
 * regexp_fixed_prefix - extract fixed prefix, if any, for a regexp
 *
 * The result is NULL if there is no fixed prefix, else a palloc'd string.
 * If it is an exact match, not just a prefix, *exact is returned as TRUE.
 */
char *
regexp_fixed_prefix(text *text_re, bool case_insensitive, Oid collation,
					bool *exact)
{
	char	   *result;
	regex_t    *re;
	int			cflags;
	int			re_result;
	pg_wchar   *str;
	size_t		slen;
	size_t		maxlen;
	char		errMsg[100];

	*exact = false;				/* default result */

	/* Compile RE */
	cflags = REG_ADVANCED;
	if (case_insensitive)
		cflags |= REG_ICASE;

	re = RE_compile_and_cache(text_re, cflags, collation);

	/* Examine it to see if there's a fixed prefix */
	re_result = pg_regprefix(re, &str, &slen);

	switch (re_result)
	{
		case REG_NOMATCH:
			return NULL;

		case REG_PREFIX:
			/* continue with wchar conversion */
			break;

		case REG_EXACT:
			*exact = true;
			/* continue with wchar conversion */
			break;

		default:
			/* re failed??? */
			CHECK_FOR_INTERRUPTS();
			pg_regerror(re_result, re, errMsg, sizeof(errMsg));
			ereport(ERROR,
					(errcode(ERRCODE_INVALID_REGULAR_EXPRESSION),
					 errmsg("regular expression failed: %s", errMsg)));
			break;
	}

	/* Convert pg_wchar result back to database encoding */
	maxlen = pg_database_encoding_max_length() * slen + 1;
	result = (char *) palloc(maxlen);
	slen = pg_wchar2mb_with_len(str, result, slen);
	Assert(slen < maxlen);

	free(str);

	return result;
}
示例#3
0
/*
 * RE_compile_and_execute - compile and execute a RE
 *
 * Returns TRUE on match, FALSE on no match
 *
 *	text_re --- the pattern, expressed as an *untoasted* TEXT object
 *	dat --- the data to match against (need not be null-terminated)
 *	dat_len --- the length of the data string
 *	cflags --- compile options for the pattern
 *	nmatch, pmatch	--- optional return area for match details
 *
 * Both pattern and data are given in the database encoding.  We internally
 * convert to array of pg_wchar which is what Spencer's regex package wants.
 */
static bool
RE_compile_and_execute(text *text_re, char *dat, int dat_len,
					   int cflags, int nmatch, regmatch_t *pmatch)
{
	pg_wchar   *data;
	size_t		data_len;
	int			regexec_result;
	regex_t    *re;
	char		errMsg[100];

	/* Convert data string to wide characters */
	data = (pg_wchar *) palloc((dat_len + 1) * sizeof(pg_wchar));
	data_len = pg_mb2wchar_with_len(dat, data, dat_len);

	/* Compile RE */
	re = RE_compile_and_cache(text_re, cflags);

	/* Perform RE match and return result */
	regexec_result = pg_regexec(re,
								data,
								data_len,
								0,
								NULL,	/* no details */
								nmatch,
								pmatch,
								0);

	pfree(data);

	if (regexec_result != REG_OKAY && regexec_result != REG_NOMATCH)
	{
		/* re failed??? */
		pg_regerror(regexec_result, re, errMsg, sizeof(errMsg));
		ereport(ERROR,
				(errcode(ERRCODE_INVALID_REGULAR_EXPRESSION),
				 errmsg("regular expression failed: %s", errMsg)));
	}

	return (regexec_result == REG_OKAY);
}
示例#4
0
/*
 * RE_compile_and_cache - compile a RE, caching if possible
 *
 * Returns regex_t *
 *
 *	text_re --- the pattern, expressed as an *untoasted* TEXT object
 *	cflags --- compile options for the pattern
 *
 * Pattern is given in the database encoding.  We internally convert to
 * array of pg_wchar which is what Spencer's regex package wants.
 */
static regex_t *
RE_compile_and_cache(text *text_re, int cflags)
{
	int			text_re_len = VARSIZE(text_re);
	pg_wchar   *pattern;
	size_t		pattern_len;
	int			i;
	int			regcomp_result;
	cached_re_str re_temp;
	char		errMsg[100];

	/*
	 * Look for a match among previously compiled REs.	Since the data
	 * structure is self-organizing with most-used entries at the front, our
	 * search strategy can just be to scan from the front.
	 */
	for (i = 0; i < num_res; i++)
	{
		if (VARSIZE(re_array[i].cre_pat) == text_re_len &&
			memcmp(re_array[i].cre_pat, text_re, text_re_len) == 0 &&
			re_array[i].cre_flags == cflags)
		{
			/*
			 * Found a match; move it to front if not there already.
			 */
			if (i > 0)
			{
				re_temp = re_array[i];
				memmove(&re_array[1], &re_array[0], i * sizeof(cached_re_str));
				re_array[0] = re_temp;
			}

			return &re_array[0].cre_re;
		}
	}

	/*
	 * Couldn't find it, so try to compile the new RE.  To avoid leaking
	 * resources on failure, we build into the re_temp local.
	 */

	/* Convert pattern string to wide characters */
	pattern = (pg_wchar *) palloc((text_re_len - VARHDRSZ + 1) * sizeof(pg_wchar));
	pattern_len = pg_mb2wchar_with_len(VARDATA(text_re),
									   pattern,
									   text_re_len - VARHDRSZ);

	regcomp_result = pg_regcomp(&re_temp.cre_re,
								pattern,
								pattern_len,
								cflags);

	pfree(pattern);

	if (regcomp_result != REG_OKAY)
	{
		/* re didn't compile */
		pg_regerror(regcomp_result, &re_temp.cre_re, errMsg, sizeof(errMsg));
		/* XXX should we pg_regfree here? */
		ereport(ERROR,
				(errcode(ERRCODE_INVALID_REGULAR_EXPRESSION),
				 errmsg("invalid regular expression: %s", errMsg)));
	}

	/*
	 * use malloc/free for the cre_pat field because the storage has to
	 * persist across transactions
	 */
	re_temp.cre_pat = malloc(text_re_len);
	if (re_temp.cre_pat == NULL)
	{
		pg_regfree(&re_temp.cre_re);
		ereport(ERROR,
				(errcode(ERRCODE_OUT_OF_MEMORY),
				 errmsg("out of memory")));
	}
	memcpy(re_temp.cre_pat, text_re, text_re_len);
	re_temp.cre_flags = cflags;

	/*
	 * Okay, we have a valid new item in re_temp; insert it into the storage
	 * array.  Discard last entry if needed.
	 */
	if (num_res >= MAX_CACHED_RES)
	{
		--num_res;
		Assert(num_res < MAX_CACHED_RES);
		pg_regfree(&re_array[num_res].cre_re);
		free(re_array[num_res].cre_pat);
	}

	if (num_res > 0)
		memmove(&re_array[1], &re_array[0], num_res * sizeof(cached_re_str));

	re_array[0] = re_temp;
	num_res++;

	return &re_array[0].cre_re;
}
示例#5
0
/*
 * RE_compile_and_cache - compile a RE, caching if possible
 *
 * Returns regex_t *
 *
 *	text_re --- the pattern, expressed as a TEXT object
 *	cflags --- compile options for the pattern
 *	collation --- collation to use for LC_CTYPE-dependent behavior
 *
 * Pattern is given in the database encoding.  We internally convert to
 * an array of pg_wchar, which is what Spencer's regex package wants.
 */
static regex_t *
RE_compile_and_cache(text *text_re, int cflags, Oid collation)
{
	int			text_re_len = VARSIZE_ANY_EXHDR(text_re);
	char	   *text_re_val = VARDATA_ANY(text_re);
	pg_wchar   *pattern;
	int			pattern_len;
	int			i;
	int			regcomp_result;
	cached_re_str re_temp;
	char		errMsg[100];

	/*
	 * Look for a match among previously compiled REs.  Since the data
	 * structure is self-organizing with most-used entries at the front, our
	 * search strategy can just be to scan from the front.
	 */
	for (i = 0; i < num_res; i++)
	{
		if (re_array[i].cre_pat_len == text_re_len &&
			re_array[i].cre_flags == cflags &&
			re_array[i].cre_collation == collation &&
			memcmp(re_array[i].cre_pat, text_re_val, text_re_len) == 0)
		{
			/*
			 * Found a match; move it to front if not there already.
			 */
			if (i > 0)
			{
				re_temp = re_array[i];
				memmove(&re_array[1], &re_array[0], i * sizeof(cached_re_str));
				re_array[0] = re_temp;
			}

			return &re_array[0].cre_re;
		}
	}

	/*
	 * Couldn't find it, so try to compile the new RE.  To avoid leaking
	 * resources on failure, we build into the re_temp local.
	 */

	/* Convert pattern string to wide characters */
	pattern = (pg_wchar *) palloc((text_re_len + 1) * sizeof(pg_wchar));
	pattern_len = pg_mb2wchar_with_len(text_re_val,
									   pattern,
									   text_re_len);

	regcomp_result = pg_regcomp(&re_temp.cre_re,
								pattern,
								pattern_len,
								cflags,
								collation);

	pfree(pattern);

	if (regcomp_result != REG_OKAY)
	{
		/* re didn't compile (no need for pg_regfree, if so) */

		/*
		 * Here and in other places in this file, do CHECK_FOR_INTERRUPTS
		 * before reporting a regex error.  This is so that if the regex
		 * library aborts and returns REG_CANCEL, we don't print an error
		 * message that implies the regex was invalid.
		 */
		CHECK_FOR_INTERRUPTS();

		pg_regerror(regcomp_result, &re_temp.cre_re, errMsg, sizeof(errMsg));
		ereport(ERROR,
				(errcode(ERRCODE_INVALID_REGULAR_EXPRESSION),
				 errmsg("invalid regular expression: %s", errMsg)));
	}

	/*
	 * We use malloc/free for the cre_pat field because the storage has to
	 * persist across transactions, and because we want to get control back on
	 * out-of-memory.  The Max() is because some malloc implementations return
	 * NULL for malloc(0).
	 */
	re_temp.cre_pat = malloc(Max(text_re_len, 1));
	if (re_temp.cre_pat == NULL)
	{
		pg_regfree(&re_temp.cre_re);
		ereport(ERROR,
				(errcode(ERRCODE_OUT_OF_MEMORY),
				 errmsg("out of memory")));
	}
	memcpy(re_temp.cre_pat, text_re_val, text_re_len);
	re_temp.cre_pat_len = text_re_len;
	re_temp.cre_flags = cflags;
	re_temp.cre_collation = collation;

	/*
	 * Okay, we have a valid new item in re_temp; insert it into the storage
	 * array.  Discard last entry if needed.
	 */
	if (num_res >= MAX_CACHED_RES)
	{
		--num_res;
		Assert(num_res < MAX_CACHED_RES);
		pg_regfree(&re_array[num_res].cre_re);
		free(re_array[num_res].cre_pat);
	}

	if (num_res > 0)
		memmove(&re_array[1], &re_array[0], num_res * sizeof(cached_re_str));

	re_array[0] = re_temp;
	num_res++;

	return &re_array[0].cre_re;
}