1 /*************************************************
2 * Perl-Compatible Regular Expressions *
3 *************************************************/
4
5 /* PCRE is a library of functions to support regular expressions whose syntax
6 and semantics are as close as possible to those of the Perl 5 language.
7
8 Written by Philip Hazel
9 Copyright (c) 1997-2006 University of Cambridge
10
11 -----------------------------------------------------------------------------
12 Redistribution and use in source and binary forms, with or without
13 modification, are permitted provided that the following conditions are met:
14
15 * Redistributions of source code must retain the above copyright notice,
16 this list of conditions and the following disclaimer.
17
18 * Redistributions in binary form must reproduce the above copyright
19 notice, this list of conditions and the following disclaimer in the
20 documentation and/or other materials provided with the distribution.
21
22 * Neither the name of the University of Cambridge nor the names of its
23 contributors may be used to endorse or promote products derived from
24 this software without specific prior written permission.
25
26 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
27 AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28 IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29 ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
30 LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31 CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32 SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33 INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34 CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35 ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36 POSSIBILITY OF SUCH DAMAGE.
37 -----------------------------------------------------------------------------
38 */
39
40
41 /* This module is a wrapper that provides a POSIX API to the underlying PCRE
42 functions. */
43
44
45 #include "pcre_internal.h"
46 #include "pcreposix.h"
47 #include "stdlib.h"
48
49
50
51 /* Table to translate PCRE compile time error codes into POSIX error codes. */
52
53 static const int eint[] = {
54 0, /* no error */
55 REG_EESCAPE, /* \ at end of pattern */
56 REG_EESCAPE, /* \c at end of pattern */
57 REG_EESCAPE, /* unrecognized character follows \ */
58 REG_BADBR, /* numbers out of order in {} quantifier */
59 REG_BADBR, /* number too big in {} quantifier */
60 REG_EBRACK, /* missing terminating ] for character class */
61 REG_ECTYPE, /* invalid escape sequence in character class */
62 REG_ERANGE, /* range out of order in character class */
63 REG_BADRPT, /* nothing to repeat */
64 REG_BADRPT, /* operand of unlimited repeat could match the empty string */
65 REG_ASSERT, /* internal error: unexpected repeat */
66 REG_BADPAT, /* unrecognized character after (? */
67 REG_BADPAT, /* POSIX named classes are supported only within a class */
68 REG_EPAREN, /* missing ) */
69 REG_ESUBREG, /* reference to non-existent subpattern */
70 REG_INVARG, /* erroffset passed as NULL */
71 REG_INVARG, /* unknown option bit(s) set */
72 REG_EPAREN, /* missing ) after comment */
73 REG_ESIZE, /* parentheses nested too deeply */
74 REG_ESIZE, /* regular expression too large */
75 REG_ESPACE, /* failed to get memory */
76 REG_EPAREN, /* unmatched brackets */
77 REG_ASSERT, /* internal error: code overflow */
78 REG_BADPAT, /* unrecognized character after (?< */
79 REG_BADPAT, /* lookbehind assertion is not fixed length */
80 REG_BADPAT, /* malformed number or name after (?( */
81 REG_BADPAT, /* conditional group contains more than two branches */
82 REG_BADPAT, /* assertion expected after (?( */
83 REG_BADPAT, /* (?R or (?digits must be followed by ) */
84 REG_ECTYPE, /* unknown POSIX class name */
85 REG_BADPAT, /* POSIX collating elements are not supported */
86 REG_INVARG, /* this version of PCRE is not compiled with PCRE_UTF8 support */
87 REG_BADPAT, /* spare error */
88 REG_BADPAT, /* character value in \x{...} sequence is too large */
89 REG_BADPAT, /* invalid condition (?(0) */
90 REG_BADPAT, /* \C not allowed in lookbehind assertion */
91 REG_EESCAPE, /* PCRE does not support \L, \l, \N, \U, or \u */
92 REG_BADPAT, /* number after (?C is > 255 */
93 REG_BADPAT, /* closing ) for (?C expected */
94 REG_BADPAT, /* recursive call could loop indefinitely */
95 REG_BADPAT, /* unrecognized character after (?P */
96 REG_BADPAT, /* syntax error in subpattern name (missing terminator) */
97 REG_BADPAT, /* two named subpatterns have the same name */
98 REG_BADPAT, /* invalid UTF-8 string */
99 REG_BADPAT, /* support for \P, \p, and \X has not been compiled */
100 REG_BADPAT, /* malformed \P or \p sequence */
101 REG_BADPAT, /* unknown property name after \P or \p */
102 REG_BADPAT, /* subpattern name is too long (maximum 32 characters) */
103 REG_BADPAT, /* too many named subpatterns (maximum 10,000) */
104 REG_BADPAT, /* repeated subpattern is too long */
105 REG_BADPAT, /* octal value is greater than \377 (not in UTF-8 mode) */
106 REG_BADPAT, /* internal error: overran compiling workspace */
107 REG_BADPAT, /* internal error: previously-checked referenced subpattern not found */
108 REG_BADPAT, /* DEFINE group contains more than one branch */
109 REG_BADPAT, /* repeating a DEFINE group is not allowed */
110 REG_INVARG, /* inconsistent NEWLINE options */
111 REG_BADPAT /* \g is not followed followed by an (optionally braced) non-zero number */
112 };
113
114 /* Table of texts corresponding to POSIX error codes */
115
116 static const char *const pstring[] = {
117 "", /* Dummy for value 0 */
118 "internal error", /* REG_ASSERT */
119 "invalid repeat counts in {}", /* BADBR */
120 "pattern error", /* BADPAT */
121 "? * + invalid", /* BADRPT */
122 "unbalanced {}", /* EBRACE */
123 "unbalanced []", /* EBRACK */
124 "collation error - not relevant", /* ECOLLATE */
125 "bad class", /* ECTYPE */
126 "bad escape sequence", /* EESCAPE */
127 "empty expression", /* EMPTY */
128 "unbalanced ()", /* EPAREN */
129 "bad range inside []", /* ERANGE */
130 "expression too big", /* ESIZE */
131 "failed to get memory", /* ESPACE */
132 "bad back reference", /* ESUBREG */
133 "bad argument", /* INVARG */
134 "match failed" /* NOMATCH */
135 };
136
137
138
139
140 /*************************************************
141 * Translate error code to string *
142 *************************************************/
143
144 PCRE_DATA_SCOPE size_t
regerror(int errcode,const regex_t * preg,char * errbuf,size_t errbuf_size)145 regerror(int errcode, const regex_t *preg, char *errbuf, size_t errbuf_size)
146 {
147 const char *message, *addmessage;
148 size_t length, addlength;
149
150 message = (errcode >= (int)(sizeof(pstring)/sizeof(char *)))?
151 "unknown error code" : pstring[errcode];
152 length = strlen(message) + 1;
153
154 addmessage = " at offset ";
155 addlength = (preg != NULL && (int)preg->re_erroffset != -1)?
156 strlen(addmessage) + 6 : 0;
157
158 if (errbuf_size > 0)
159 {
160 if (addlength > 0 && errbuf_size >= length + addlength)
161 sprintf(errbuf, "%s%s%-6d", message, addmessage, (int)preg->re_erroffset);
162 else
163 {
164 strncpy(errbuf, message, errbuf_size - 1);
165 errbuf[errbuf_size-1] = 0;
166 }
167 }
168
169 return length + addlength;
170 }
171
172
173
174
175 /*************************************************
176 * Free store held by a regex *
177 *************************************************/
178
179 PCRE_DATA_SCOPE void
regfree(regex_t * preg)180 regfree(regex_t *preg)
181 {
182 (pcre_free)(preg->re_pcre);
183 }
184
185
186
187
188 /*************************************************
189 * Compile a regular expression *
190 *************************************************/
191
192 /*
193 Arguments:
194 preg points to a structure for recording the compiled expression
195 pattern the pattern to compile
196 cflags compilation flags
197
198 Returns: 0 on success
199 various non-zero codes on failure
200 */
201
202 PCRE_DATA_SCOPE int
regcomp(regex_t * preg,const char * pattern,int cflags)203 regcomp(regex_t *preg, const char *pattern, int cflags)
204 {
205 const char *errorptr;
206 int erroffset;
207 int errorcode;
208 int options = 0;
209
210 if ((cflags & REG_ICASE) != 0) options |= PCRE_CASELESS;
211 if ((cflags & REG_NEWLINE) != 0) options |= PCRE_MULTILINE;
212 if ((cflags & REG_DOTALL) != 0) options |= PCRE_DOTALL;
213 if ((cflags & REG_NOSUB) != 0) options |= PCRE_NO_AUTO_CAPTURE;
214 if ((cflags & REG_UTF8) != 0) options |= PCRE_UTF8;
215
216 preg->re_pcre = pcre_compile2(pattern, options, &errorcode, &errorptr,
217 &erroffset, NULL);
218 preg->re_erroffset = erroffset;
219
220 if (preg->re_pcre == NULL) return eint[errorcode];
221
222 preg->re_nsub = pcre_info((const pcre *)preg->re_pcre, NULL, NULL);
223 return 0;
224 }
225
226
227
228
229 /*************************************************
230 * Match a regular expression *
231 *************************************************/
232
233 /* Unfortunately, PCRE requires 3 ints of working space for each captured
234 substring, so we have to get and release working store instead of just using
235 the POSIX structures as was done in earlier releases when PCRE needed only 2
236 ints. However, if the number of possible capturing brackets is small, use a
237 block of store on the stack, to reduce the use of malloc/free. The threshold is
238 in a macro that can be changed at configure time.
239
240 If REG_NOSUB was specified at compile time, the PCRE_NO_AUTO_CAPTURE flag will
241 be set. When this is the case, the nmatch and pmatch arguments are ignored, and
242 the only result is yes/no/error. */
243
244 PCRE_DATA_SCOPE int
regexec(const regex_t * preg,const char * string,size_t nmatch,regmatch_t pmatch[],int eflags)245 regexec(const regex_t *preg, const char *string, size_t nmatch,
246 regmatch_t pmatch[], int eflags)
247 {
248 int rc;
249 int options = 0;
250 int *ovector = NULL;
251 int small_ovector[POSIX_MALLOC_THRESHOLD * 3];
252 BOOL allocated_ovector = FALSE;
253 BOOL nosub =
254 (((const pcre *)preg->re_pcre)->options & PCRE_NO_AUTO_CAPTURE) != 0;
255
256 if ((eflags & REG_NOTBOL) != 0) options |= PCRE_NOTBOL;
257 if ((eflags & REG_NOTEOL) != 0) options |= PCRE_NOTEOL;
258
259 ((regex_t *)preg)->re_erroffset = (size_t)(-1); /* Only has meaning after compile */
260
261 /* When no string data is being returned, ensure that nmatch is zero.
262 Otherwise, ensure the vector for holding the return data is large enough. */
263
264 if (nosub) nmatch = 0;
265
266 else if (nmatch > 0)
267 {
268 if (nmatch <= POSIX_MALLOC_THRESHOLD)
269 {
270 ovector = &(small_ovector[0]);
271 }
272 else
273 {
274 if (nmatch > INT_MAX/(sizeof(int) * 3)) return REG_ESPACE;
275 ovector = (int *)malloc(sizeof(int) * nmatch * 3);
276 if (ovector == NULL) return REG_ESPACE;
277 allocated_ovector = TRUE;
278 }
279 }
280
281 rc = pcre_exec((const pcre *)preg->re_pcre, NULL, string, (int)strlen(string),
282 0, options, ovector, nmatch * 3);
283
284 if (rc == 0) rc = nmatch; /* All captured slots were filled in */
285
286 if (rc >= 0)
287 {
288 size_t i;
289 if (!nosub)
290 {
291 for (i = 0; i < (size_t)rc; i++)
292 {
293 pmatch[i].rm_so = ovector[i*2];
294 pmatch[i].rm_eo = ovector[i*2+1];
295 }
296 if (allocated_ovector) free(ovector);
297 for (; i < nmatch; i++) pmatch[i].rm_so = pmatch[i].rm_eo = -1;
298 }
299 return 0;
300 }
301
302 else
303 {
304 if (allocated_ovector) free(ovector);
305 switch(rc)
306 {
307 case PCRE_ERROR_NOMATCH: return REG_NOMATCH;
308 case PCRE_ERROR_NULL: return REG_INVARG;
309 case PCRE_ERROR_BADOPTION: return REG_INVARG;
310 case PCRE_ERROR_BADMAGIC: return REG_INVARG;
311 case PCRE_ERROR_UNKNOWN_NODE: return REG_ASSERT;
312 case PCRE_ERROR_NOMEMORY: return REG_ESPACE;
313 case PCRE_ERROR_MATCHLIMIT: return REG_ESPACE;
314 case PCRE_ERROR_BADUTF8: return REG_INVARG;
315 case PCRE_ERROR_BADUTF8_OFFSET: return REG_INVARG;
316 default: return REG_ASSERT;
317 }
318 }
319 }
320
321 /* End of pcreposix.c */
322