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 Original API code Copyright (c) 1997-2012 University of Cambridge
10 New API code Copyright (c) 2016 University of Cambridge
11
12 -----------------------------------------------------------------------------
13 Redistribution and use in source and binary forms, with or without
14 modification, are permitted provided that the following conditions are met:
15
16 * Redistributions of source code must retain the above copyright notice,
17 this list of conditions and the following disclaimer.
18
19 * Redistributions in binary form must reproduce the above copyright
20 notice, this list of conditions and the following disclaimer in the
21 documentation and/or other materials provided with the distribution.
22
23 * Neither the name of the University of Cambridge nor the names of its
24 contributors may be used to endorse or promote products derived from
25 this software without specific prior written permission.
26
27 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
28 AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
29 IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
30 ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
31 LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
32 CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
33 SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
34 INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
35 CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
36 ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
37 POSSIBILITY OF SUCH DAMAGE.
38 -----------------------------------------------------------------------------
39 */
40
41
42 /* This module is a wrapper that provides a POSIX API to the underlying PCRE2
43 functions. */
44
45
46 #ifdef HAVE_CONFIG_H
47 #include "config.h"
48 #endif
49
50
51 /* Ensure that the PCRE2POSIX_EXP_xxx macros are set appropriately for
52 compiling these functions. This must come before including pcre2posix.h, where
53 they are set for an application (using these functions) if they have not
54 previously been set. */
55
56 #if defined(_WIN32) && !defined(PCRE2_STATIC)
57 # define PCRE2POSIX_EXP_DECL extern __declspec(dllexport)
58 # define PCRE2POSIX_EXP_DEFN __declspec(dllexport)
59 #endif
60
61 /* Older versions of MSVC lack snprintf(). This define allows for
62 warning/error-free compilation and testing with MSVC compilers back to at least
63 MSVC 10/2010. Except for VC6 (which is missing some fundamentals and fails). */
64
65 #if defined(_MSC_VER) && (_MSC_VER < 1900)
66 #define snprintf _snprintf
67 #endif
68
69
70 /* Compile-time error numbers start at this value. It should probably never be
71 changed. This #define is a copy of the one in pcre2_internal.h. */
72
73 #define COMPILE_ERROR_BASE 100
74
75
76 /* Standard C headers */
77
78 #include <ctype.h>
79 #include <limits.h>
80 #include <stddef.h>
81 #include <stdio.h>
82 #include <stdlib.h>
83 #include <string.h>
84
85 /* PCRE2 headers */
86
87 #include "pcre2.h"
88 #include "pcre2posix.h"
89
90 /* When compiling with the MSVC compiler, it is sometimes necessary to include
91 a "calling convention" before exported function names. (This is secondhand
92 information; I know nothing about MSVC myself). For example, something like
93
94 void __cdecl function(....)
95
96 might be needed. In order so make this easy, all the exported functions have
97 PCRE2_CALL_CONVENTION just before their names. It is rarely needed; if not
98 set, we ensure here that it has no effect. */
99
100 #ifndef PCRE2_CALL_CONVENTION
101 #define PCRE2_CALL_CONVENTION
102 #endif
103
104 /* Table to translate PCRE2 compile time error codes into POSIX error codes.
105 Only a few PCRE2 errors with a value greater than 23 turn into special POSIX
106 codes: most go to REG_BADPAT. The second table lists, in pairs, those that
107 don't. */
108
109 static const int eint1[] = {
110 0, /* No error */
111 REG_EESCAPE, /* \ at end of pattern */
112 REG_EESCAPE, /* \c at end of pattern */
113 REG_EESCAPE, /* unrecognized character follows \ */
114 REG_BADBR, /* numbers out of order in {} quantifier */
115 /* 5 */
116 REG_BADBR, /* number too big in {} quantifier */
117 REG_EBRACK, /* missing terminating ] for character class */
118 REG_ECTYPE, /* invalid escape sequence in character class */
119 REG_ERANGE, /* range out of order in character class */
120 REG_BADRPT, /* nothing to repeat */
121 /* 10 */
122 REG_ASSERT, /* internal error: unexpected repeat */
123 REG_BADPAT, /* unrecognized character after (? or (?- */
124 REG_BADPAT, /* POSIX named classes are supported only within a class */
125 REG_BADPAT, /* POSIX collating elements are not supported */
126 REG_EPAREN, /* missing ) */
127 /* 15 */
128 REG_ESUBREG, /* reference to non-existent subpattern */
129 REG_INVARG, /* pattern passed as NULL */
130 REG_INVARG, /* unknown compile-time option bit(s) */
131 REG_EPAREN, /* missing ) after (?# comment */
132 REG_ESIZE, /* parentheses nested too deeply */
133 /* 20 */
134 REG_ESIZE, /* regular expression too large */
135 REG_ESPACE, /* failed to get memory */
136 REG_EPAREN, /* unmatched closing parenthesis */
137 REG_ASSERT /* internal error: code overflow */
138 };
139
140 static const int eint2[] = {
141 30, REG_ECTYPE, /* unknown POSIX class name */
142 32, REG_INVARG, /* this version of PCRE2 does not have Unicode support */
143 37, REG_EESCAPE, /* PCRE2 does not support \L, \l, \N{name}, \U, or \u */
144 56, REG_INVARG, /* internal error: unknown newline setting */
145 };
146
147 /* Table of texts corresponding to POSIX error codes */
148
149 static const char *const pstring[] = {
150 "", /* Dummy for value 0 */
151 "internal error", /* REG_ASSERT */
152 "invalid repeat counts in {}", /* BADBR */
153 "pattern error", /* BADPAT */
154 "? * + invalid", /* BADRPT */
155 "unbalanced {}", /* EBRACE */
156 "unbalanced []", /* EBRACK */
157 "collation error - not relevant", /* ECOLLATE */
158 "bad class", /* ECTYPE */
159 "bad escape sequence", /* EESCAPE */
160 "empty expression", /* EMPTY */
161 "unbalanced ()", /* EPAREN */
162 "bad range inside []", /* ERANGE */
163 "expression too big", /* ESIZE */
164 "failed to get memory", /* ESPACE */
165 "bad back reference", /* ESUBREG */
166 "bad argument", /* INVARG */
167 "match failed" /* NOMATCH */
168 };
169
170
171
172
173 /*************************************************
174 * Translate error code to string *
175 *************************************************/
176
177 PCRE2POSIX_EXP_DEFN size_t PCRE2_CALL_CONVENTION
regerror(int errcode,const regex_t * preg,char * errbuf,size_t errbuf_size)178 regerror(int errcode, const regex_t *preg, char *errbuf, size_t errbuf_size)
179 {
180 int used;
181 const char *message;
182
183 message = (errcode <= 0 || errcode >= (int)(sizeof(pstring)/sizeof(char *)))?
184 "unknown error code" : pstring[errcode];
185
186 if (preg != NULL && (int)preg->re_erroffset != -1)
187 {
188 used = snprintf(errbuf, errbuf_size, "%s at offset %-6d", message,
189 (int)preg->re_erroffset);
190 }
191 else
192 {
193 used = snprintf(errbuf, errbuf_size, "%s", message);
194 }
195
196 return used + 1;
197 }
198
199
200
201
202 /*************************************************
203 * Free store held by a regex *
204 *************************************************/
205
206 PCRE2POSIX_EXP_DEFN void PCRE2_CALL_CONVENTION
regfree(regex_t * preg)207 regfree(regex_t *preg)
208 {
209 pcre2_match_data_free(preg->re_match_data);
210 pcre2_code_free(preg->re_pcre2_code);
211 }
212
213
214
215
216 /*************************************************
217 * Compile a regular expression *
218 *************************************************/
219
220 /*
221 Arguments:
222 preg points to a structure for recording the compiled expression
223 pattern the pattern to compile
224 cflags compilation flags
225
226 Returns: 0 on success
227 various non-zero codes on failure
228 */
229
230 PCRE2POSIX_EXP_DEFN int PCRE2_CALL_CONVENTION
regcomp(regex_t * preg,const char * pattern,int cflags)231 regcomp(regex_t *preg, const char *pattern, int cflags)
232 {
233 PCRE2_SIZE erroffset;
234 int errorcode;
235 int options = 0;
236 int re_nsub = 0;
237
238 if ((cflags & REG_ICASE) != 0) options |= PCRE2_CASELESS;
239 if ((cflags & REG_NEWLINE) != 0) options |= PCRE2_MULTILINE;
240 if ((cflags & REG_DOTALL) != 0) options |= PCRE2_DOTALL;
241 if ((cflags & REG_UTF) != 0) options |= PCRE2_UTF;
242 if ((cflags & REG_UCP) != 0) options |= PCRE2_UCP;
243 if ((cflags & REG_UNGREEDY) != 0) options |= PCRE2_UNGREEDY;
244
245 preg->re_cflags = cflags;
246 preg->re_pcre2_code = pcre2_compile((PCRE2_SPTR)pattern, PCRE2_ZERO_TERMINATED,
247 options, &errorcode, &erroffset, NULL);
248 preg->re_erroffset = erroffset;
249
250 if (preg->re_pcre2_code == NULL)
251 {
252 unsigned int i;
253
254 /* A negative value is a UTF error; otherwise all error codes are greater
255 than COMPILE_ERROR_BASE, but check, just in case. */
256
257 if (errorcode < COMPILE_ERROR_BASE) return REG_BADPAT;
258 errorcode -= COMPILE_ERROR_BASE;
259
260 if (errorcode < (int)(sizeof(eint1)/sizeof(const int)))
261 return eint1[errorcode];
262 for (i = 0; i < sizeof(eint2)/(2*sizeof(const int)); i += 2)
263 if (errorcode == eint2[i]) return eint2[i+1];
264 return REG_BADPAT;
265 }
266
267 (void)pcre2_pattern_info((const pcre2_code *)preg->re_pcre2_code,
268 PCRE2_INFO_CAPTURECOUNT, &re_nsub);
269 preg->re_nsub = (size_t)re_nsub;
270 preg->re_match_data = pcre2_match_data_create(re_nsub + 1, NULL);
271
272 if (preg->re_match_data == NULL)
273 {
274 pcre2_code_free(preg->re_pcre2_code);
275 return REG_ESPACE;
276 }
277
278 return 0;
279 }
280
281
282
283 /*************************************************
284 * Match a regular expression *
285 *************************************************/
286
287 /* A suitable match_data block, large enough to hold all possible captures, was
288 obtained when the pattern was compiled, to save having to allocate and free it
289 for each match. If REG_NOSUB was specified at compile time, the
290 PCRE_NO_AUTO_CAPTURE flag will be set. When this is the case, the nmatch and
291 pmatch arguments are ignored, and the only result is yes/no/error. */
292
293 PCRE2POSIX_EXP_DEFN int PCRE2_CALL_CONVENTION
regexec(const regex_t * preg,const char * string,size_t nmatch,regmatch_t pmatch[],int eflags)294 regexec(const regex_t *preg, const char *string, size_t nmatch,
295 regmatch_t pmatch[], int eflags)
296 {
297 int rc, so, eo;
298 int options = 0;
299 pcre2_match_data *md = (pcre2_match_data *)preg->re_match_data;
300
301 if ((eflags & REG_NOTBOL) != 0) options |= PCRE2_NOTBOL;
302 if ((eflags & REG_NOTEOL) != 0) options |= PCRE2_NOTEOL;
303 if ((eflags & REG_NOTEMPTY) != 0) options |= PCRE2_NOTEMPTY;
304
305 ((regex_t *)preg)->re_erroffset = (size_t)(-1); /* Only has meaning after compile */
306
307 /* When REG_NOSUB was specified, or if no vector has been passed in which to
308 put captured strings, ensure that nmatch is zero. This will stop any attempt to
309 write to pmatch. */
310
311 if ((preg->re_cflags & REG_NOSUB) != 0 || pmatch == NULL) nmatch = 0;
312
313 /* REG_STARTEND is a BSD extension, to allow for non-NUL-terminated strings.
314 The man page from OS X says "REG_STARTEND affects only the location of the
315 string, not how it is matched". That is why the "so" value is used to bump the
316 start location rather than being passed as a PCRE2 "starting offset". */
317
318 if ((eflags & REG_STARTEND) != 0)
319 {
320 if (pmatch == NULL) return REG_INVARG;
321 so = pmatch[0].rm_so;
322 eo = pmatch[0].rm_eo;
323 }
324 else
325 {
326 so = 0;
327 eo = (int)strlen(string);
328 }
329
330 rc = pcre2_match((const pcre2_code *)preg->re_pcre2_code,
331 (PCRE2_SPTR)string + so, (eo - so), 0, options, md, NULL);
332
333 /* Successful match */
334
335 if (rc >= 0)
336 {
337 size_t i;
338 PCRE2_SIZE *ovector = pcre2_get_ovector_pointer(md);
339 if ((size_t)rc > nmatch) rc = (int)nmatch;
340 for (i = 0; i < (size_t)rc; i++)
341 {
342 pmatch[i].rm_so = ovector[i*2];
343 pmatch[i].rm_eo = ovector[i*2+1];
344 }
345 for (; i < nmatch; i++) pmatch[i].rm_so = pmatch[i].rm_eo = -1;
346 return 0;
347 }
348
349 /* Unsuccessful match */
350
351 if (rc <= PCRE2_ERROR_UTF8_ERR1 && rc >= PCRE2_ERROR_UTF8_ERR21)
352 return REG_INVARG;
353
354 switch(rc)
355 {
356 default: return REG_ASSERT;
357 case PCRE2_ERROR_BADMODE: return REG_INVARG;
358 case PCRE2_ERROR_BADMAGIC: return REG_INVARG;
359 case PCRE2_ERROR_BADOPTION: return REG_INVARG;
360 case PCRE2_ERROR_BADUTFOFFSET: return REG_INVARG;
361 case PCRE2_ERROR_MATCHLIMIT: return REG_ESPACE;
362 case PCRE2_ERROR_NOMATCH: return REG_NOMATCH;
363 case PCRE2_ERROR_NOMEMORY: return REG_ESPACE;
364 case PCRE2_ERROR_NULL: return REG_INVARG;
365 }
366 }
367
368 /* End of pcre2posix.c */
369