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"
50 #define APR_WANT_STRFUNC
53 #ifndef POSIX_MALLOC_THRESHOLD
54 #define POSIX_MALLOC_THRESHOLD (10)
57 /* Table of error strings corresponding to POSIX error codes; must be
58 * kept in synch with include/ap_regex.h's AP_REG_E* definitions.
61 static const char *const pstring[] = {
62 "", /* Dummy for value 0 */
63 "internal error", /* AP_REG_ASSERT */
64 "failed to get memory", /* AP_REG_ESPACE */
65 "bad argument", /* AP_REG_INVARG */
66 "match failed" /* AP_REG_NOMATCH */
69 AP_DECLARE(apr_size_t) ap_regerror(int errcode, const ap_regex_t *preg,
70 char *errbuf, apr_size_t errbuf_size)
72 const char *message, *addmessage;
73 apr_size_t length, addlength;
75 message = (errcode >= (int)(sizeof(pstring) / sizeof(char *))) ?
76 "unknown error code" : pstring[errcode];
77 length = strlen(message) + 1;
79 addmessage = " at offset ";
80 addlength = (preg != NULL && (int)preg->re_erroffset != -1) ?
81 strlen(addmessage) + 6 : 0;
83 if (errbuf_size > 0) {
84 if (addlength > 0 && errbuf_size >= length + addlength)
85 apr_snprintf(errbuf, errbuf_size, "%s%s%-6d", message, addmessage,
86 (int)preg->re_erroffset);
88 apr_cpystrn(errbuf, message, errbuf_size);
91 return length + addlength;
97 /*************************************************
98 * Free store held by a regex *
99 *************************************************/
101 AP_DECLARE(void) ap_regfree(ap_regex_t *preg)
103 (pcre_free)(preg->re_pcre);
109 /*************************************************
110 * Compile a regular expression *
111 *************************************************/
115 * preg points to a structure for recording the compiled expression
116 * pattern the pattern to compile
117 * cflags compilation flags
119 * Returns: 0 on success
120 * various non-zero codes on failure
122 AP_DECLARE(int) ap_regcomp(ap_regex_t * preg, const char *pattern, int cflags)
124 const char *errorptr;
128 if ((cflags & AP_REG_ICASE) != 0)
129 options |= PCRE_CASELESS;
130 if ((cflags & AP_REG_NEWLINE) != 0)
131 options |= PCRE_MULTILINE;
132 if ((cflags & AP_REG_DOTALL) != 0)
133 options |= PCRE_DOTALL;
136 pcre_compile(pattern, options, &errorptr, &erroffset, NULL);
137 preg->re_erroffset = erroffset;
139 if (preg->re_pcre == NULL)
140 return AP_REG_INVARG;
142 preg->re_nsub = pcre_info((const pcre *)preg->re_pcre, NULL, NULL);
149 /*************************************************
150 * Match a regular expression *
151 *************************************************/
153 /* Unfortunately, PCRE requires 3 ints of working space for each captured
154 * substring, so we have to get and release working store instead of just using
155 * the POSIX structures as was done in earlier releases when PCRE needed only 2
156 * ints. However, if the number of possible capturing brackets is small, use a
157 * block of store on the stack, to reduce the use of malloc/free. The threshold
158 * is in a macro that can be changed at configure time.
160 AP_DECLARE(int) ap_regexec(const ap_regex_t *preg, const char *string,
161 apr_size_t nmatch, ap_regmatch_t *pmatch,
164 return ap_regexec_len(preg, string, strlen(string), nmatch, pmatch,
168 AP_DECLARE(int) ap_regexec_len(const ap_regex_t *preg, const char *buff,
169 apr_size_t len, apr_size_t nmatch,
170 ap_regmatch_t *pmatch, int eflags)
175 int small_ovector[POSIX_MALLOC_THRESHOLD * 3];
176 int allocated_ovector = 0;
178 if ((eflags & AP_REG_NOTBOL) != 0)
179 options |= PCRE_NOTBOL;
180 if ((eflags & AP_REG_NOTEOL) != 0)
181 options |= PCRE_NOTEOL;
183 ((ap_regex_t *)preg)->re_erroffset = (apr_size_t)(-1); /* Only has meaning after compile */
186 if (nmatch <= POSIX_MALLOC_THRESHOLD) {
187 ovector = &(small_ovector[0]);
190 ovector = (int *)malloc(sizeof(int) * nmatch * 3);
192 return AP_REG_ESPACE;
193 allocated_ovector = 1;
197 rc = pcre_exec((const pcre *)preg->re_pcre, NULL, buff, (int)len,
198 0, options, ovector, nmatch * 3);
201 rc = nmatch; /* All captured slots were filled in */
205 for (i = 0; i < (apr_size_t)rc; i++) {
206 pmatch[i].rm_so = ovector[i * 2];
207 pmatch[i].rm_eo = ovector[i * 2 + 1];
209 if (allocated_ovector)
211 for (; i < nmatch; i++)
212 pmatch[i].rm_so = pmatch[i].rm_eo = -1;
217 if (allocated_ovector)
220 case PCRE_ERROR_NOMATCH:
221 return AP_REG_NOMATCH;
222 case PCRE_ERROR_NULL:
223 return AP_REG_INVARG;
224 case PCRE_ERROR_BADOPTION:
225 return AP_REG_INVARG;
226 case PCRE_ERROR_BADMAGIC:
227 return AP_REG_INVARG;
228 case PCRE_ERROR_UNKNOWN_NODE:
229 return AP_REG_ASSERT;
230 case PCRE_ERROR_NOMEMORY:
231 return AP_REG_ESPACE;
232 #ifdef PCRE_ERROR_MATCHLIMIT
233 case PCRE_ERROR_MATCHLIMIT:
234 return AP_REG_ESPACE;
236 #ifdef PCRE_ERROR_BADUTF8
237 case PCRE_ERROR_BADUTF8:
238 return AP_REG_INVARG;
240 #ifdef PCRE_ERROR_BADUTF8_OFFSET
241 case PCRE_ERROR_BADUTF8_OFFSET:
242 return AP_REG_INVARG;
245 return AP_REG_ASSERT;
250 /* End of pcreposix.c */