1 /*************************************************
2 * Perl-Compatible Regular Expressions *
3 *************************************************/
6 This is a library of functions to support regular expressions whose syntax
7 and semantics are as close as possible to those of the Perl 5 language. See
8 the file Tech.Notes for some information on the internals.
10 This module is a wrapper that provides a POSIX API to the underlying PCRE
13 Written by: Philip Hazel <ph10@cam.ac.uk>
15 Copyright (c) 1997-2004 University of Cambridge
17 -----------------------------------------------------------------------------
18 Redistribution and use in source and binary forms, with or without
19 modification, are permitted provided that the following conditions are met:
21 * Redistributions of source code must retain the above copyright notice,
22 this list of conditions and the following disclaimer.
24 * Redistributions in binary form must reproduce the above copyright
25 notice, this list of conditions and the following disclaimer in the
26 documentation and/or other materials provided with the distribution.
28 * Neither the name of the University of Cambridge nor the names of its
29 contributors may be used to endorse or promote products derived from
30 this software without specific prior written permission.
32 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
33 AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
34 IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
35 ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
36 LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
37 CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
38 SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
39 INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
40 CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
41 ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
42 POSSIBILITY OF SUCH DAMAGE.
43 -----------------------------------------------------------------------------
47 #include "apr_strings.h"
48 #include "apr_tables.h"
51 #define APR_WANT_STRFUNC
54 #ifndef POSIX_MALLOC_THRESHOLD
55 #define POSIX_MALLOC_THRESHOLD (10)
58 /* Table of error strings corresponding to POSIX error codes; must be
59 * kept in synch with include/ap_regex.h's AP_REG_E* definitions.
62 static const char *const pstring[] = {
63 "", /* Dummy for value 0 */
64 "internal error", /* AP_REG_ASSERT */
65 "failed to get memory", /* AP_REG_ESPACE */
66 "bad argument", /* AP_REG_INVARG */
67 "match failed" /* AP_REG_NOMATCH */
70 AP_DECLARE(apr_size_t) ap_regerror(int errcode, const ap_regex_t *preg,
71 char *errbuf, apr_size_t errbuf_size)
73 const char *message, *addmessage;
74 apr_size_t length, addlength;
76 message = (errcode >= (int)(sizeof(pstring) / sizeof(char *))) ?
77 "unknown error code" : pstring[errcode];
78 length = strlen(message) + 1;
80 addmessage = " at offset ";
81 addlength = (preg != NULL && (int)preg->re_erroffset != -1) ?
82 strlen(addmessage) + 6 : 0;
84 if (errbuf_size > 0) {
85 if (addlength > 0 && errbuf_size >= length + addlength)
86 apr_snprintf(errbuf, errbuf_size, "%s%s%-6d", message, addmessage,
87 (int)preg->re_erroffset);
89 apr_cpystrn(errbuf, message, errbuf_size);
92 return length + addlength;
98 /*************************************************
99 * Free store held by a regex *
100 *************************************************/
102 AP_DECLARE(void) ap_regfree(ap_regex_t *preg)
104 (pcre_free)(preg->re_pcre);
110 /*************************************************
111 * Compile a regular expression *
112 *************************************************/
116 * preg points to a structure for recording the compiled expression
117 * pattern the pattern to compile
118 * cflags compilation flags
120 * Returns: 0 on success
121 * various non-zero codes on failure
123 AP_DECLARE(int) ap_regcomp(ap_regex_t * preg, const char *pattern, int cflags)
125 const char *errorptr;
128 /* PCRE_DUPNAMES is only present in more recent versions of PCRE */
130 int options = PCRE_DUPNAMES;
132 #error PCRE_DUPNAMES does not exist in this PCRE implementation; too old.
135 if ((cflags & AP_REG_ICASE) != 0)
136 options |= PCRE_CASELESS;
137 if ((cflags & AP_REG_NEWLINE) != 0)
138 options |= PCRE_MULTILINE;
139 if ((cflags & AP_REG_DOTALL) != 0)
140 options |= PCRE_DOTALL;
143 pcre_compile2(pattern, options, &errcode, &errorptr, &erroffset, NULL);
144 preg->re_erroffset = erroffset;
146 if (preg->re_pcre == NULL) {
148 * There doesn't seem to be constants defined for compile time error
149 * codes. 21 is "failed to get memory" according to pcreapi(3).
152 return AP_REG_ESPACE;
153 return AP_REG_INVARG;
156 pcre_fullinfo((const pcre *)preg->re_pcre, NULL,
157 PCRE_INFO_CAPTURECOUNT, &(preg->re_nsub));
164 /*************************************************
165 * Match a regular expression *
166 *************************************************/
168 /* Unfortunately, PCRE requires 3 ints of working space for each captured
169 * substring, so we have to get and release working store instead of just using
170 * the POSIX structures as was done in earlier releases when PCRE needed only 2
171 * ints. However, if the number of possible capturing brackets is small, use a
172 * block of store on the stack, to reduce the use of malloc/free. The threshold
173 * is in a macro that can be changed at configure time.
175 AP_DECLARE(int) ap_regexec(const ap_regex_t *preg, const char *string,
176 apr_size_t nmatch, ap_regmatch_t *pmatch,
179 return ap_regexec_len(preg, string, strlen(string), nmatch, pmatch,
183 AP_DECLARE(int) ap_regexec_len(const ap_regex_t *preg, const char *buff,
184 apr_size_t len, apr_size_t nmatch,
185 ap_regmatch_t *pmatch, int eflags)
190 int small_ovector[POSIX_MALLOC_THRESHOLD * 3];
191 int allocated_ovector = 0;
193 if ((eflags & AP_REG_NOTBOL) != 0)
194 options |= PCRE_NOTBOL;
195 if ((eflags & AP_REG_NOTEOL) != 0)
196 options |= PCRE_NOTEOL;
198 ((ap_regex_t *)preg)->re_erroffset = (apr_size_t)(-1); /* Only has meaning after compile */
201 if (nmatch <= POSIX_MALLOC_THRESHOLD) {
202 ovector = &(small_ovector[0]);
205 ovector = (int *)malloc(sizeof(int) * nmatch * 3);
207 return AP_REG_ESPACE;
208 allocated_ovector = 1;
212 rc = pcre_exec((const pcre *)preg->re_pcre, NULL, buff, (int)len,
213 0, options, ovector, nmatch * 3);
216 rc = nmatch; /* All captured slots were filled in */
220 for (i = 0; i < (apr_size_t)rc; i++) {
221 pmatch[i].rm_so = ovector[i * 2];
222 pmatch[i].rm_eo = ovector[i * 2 + 1];
224 if (allocated_ovector)
226 for (; i < nmatch; i++)
227 pmatch[i].rm_so = pmatch[i].rm_eo = -1;
232 if (allocated_ovector)
235 case PCRE_ERROR_NOMATCH:
236 return AP_REG_NOMATCH;
237 case PCRE_ERROR_NULL:
238 return AP_REG_INVARG;
239 case PCRE_ERROR_BADOPTION:
240 return AP_REG_INVARG;
241 case PCRE_ERROR_BADMAGIC:
242 return AP_REG_INVARG;
243 case PCRE_ERROR_UNKNOWN_NODE:
244 return AP_REG_ASSERT;
245 case PCRE_ERROR_NOMEMORY:
246 return AP_REG_ESPACE;
247 #ifdef PCRE_ERROR_MATCHLIMIT
248 case PCRE_ERROR_MATCHLIMIT:
249 return AP_REG_ESPACE;
251 #ifdef PCRE_ERROR_BADUTF8
252 case PCRE_ERROR_BADUTF8:
253 return AP_REG_INVARG;
255 #ifdef PCRE_ERROR_BADUTF8_OFFSET
256 case PCRE_ERROR_BADUTF8_OFFSET:
257 return AP_REG_INVARG;
260 return AP_REG_ASSERT;
265 AP_DECLARE(int) ap_regname(const ap_regex_t *preg,
266 apr_array_header_t *names, const char *prefix,
274 pcre_fullinfo((const pcre *)preg->re_pcre, NULL,
275 PCRE_INFO_NAMECOUNT, &namecount);
276 pcre_fullinfo((const pcre *)preg->re_pcre, NULL,
277 PCRE_INFO_NAMEENTRYSIZE, &nameentrysize);
278 pcre_fullinfo((const pcre *)preg->re_pcre, NULL,
279 PCRE_INFO_NAMETABLE, &nametable);
281 for (i = 0; i < namecount; i++) {
282 const char *offset = nametable + i * nameentrysize;
283 int capture = ((offset[0] << 8) + offset[1]);
284 while (names->nelts <= capture) {
285 apr_array_push(names);
287 if (upper || prefix) {
288 char *name = ((char **) names->elts)[capture] =
289 prefix ? apr_pstrcat(names->pool, prefix, offset + 2,
291 apr_pstrdup(names->pool, offset + 2);
293 ap_str_toupper(name);
297 ((const char **)names->elts)[capture] = offset + 2;
304 /* End of pcreposix.c */