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) 2016-2018 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 to 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 92, REG_INVARG, /* invalid option bits with PCRE2_LITERAL */
146 };
147
148 /* Table of texts corresponding to POSIX error codes */
149
150 static const char *const pstring[] = {
151 "", /* Dummy for value 0 */
152 "internal error", /* REG_ASSERT */
153 "invalid repeat counts in {}", /* BADBR */
154 "pattern error", /* BADPAT */
155 "? * + invalid", /* BADRPT */
156 "unbalanced {}", /* EBRACE */
157 "unbalanced []", /* EBRACK */
158 "collation error - not relevant", /* ECOLLATE */
159 "bad class", /* ECTYPE */
160 "bad escape sequence", /* EESCAPE */
161 "empty expression", /* EMPTY */
162 "unbalanced ()", /* EPAREN */
163 "bad range inside []", /* ERANGE */
164 "expression too big", /* ESIZE */
165 "failed to get memory", /* ESPACE */
166 "bad back reference", /* ESUBREG */
167 "bad argument", /* INVARG */
168 "match failed" /* NOMATCH */
169 };
170
171
172
173
174 /*************************************************
175 * Translate error code to string *
176 *************************************************/
177
178 PCRE2POSIX_EXP_DEFN size_t PCRE2_CALL_CONVENTION
regerror(int errcode,const regex_t * preg,char * errbuf,size_t errbuf_size)179 regerror(int errcode, const regex_t *preg, char *errbuf, size_t errbuf_size)
180 {
181 int used;
182 const char *message;
183
184 message = (errcode <= 0 || errcode >= (int)(sizeof(pstring)/sizeof(char *)))?
185 "unknown error code" : pstring[errcode];
186
187 if (preg != NULL && (int)preg->re_erroffset != -1)
188 {
189 used = snprintf(errbuf, errbuf_size, "%s at offset %-6d", message,
190 (int)preg->re_erroffset);
191 }
192 else
193 {
194 used = snprintf(errbuf, errbuf_size, "%s", message);
195 }
196
197 return used + 1;
198 }
199
200
201
202
203 /*************************************************
204 * Free store held by a regex *
205 *************************************************/
206
207 PCRE2POSIX_EXP_DEFN void PCRE2_CALL_CONVENTION
regfree(regex_t * preg)208 regfree(regex_t *preg)
209 {
210 pcre2_match_data_free(preg->re_match_data);
211 pcre2_code_free(preg->re_pcre2_code);
212 }
213
214
215
216
217 /*************************************************
218 * Compile a regular expression *
219 *************************************************/
220
221 /*
222 Arguments:
223 preg points to a structure for recording the compiled expression
224 pattern the pattern to compile
225 cflags compilation flags
226
227 Returns: 0 on success
228 various non-zero codes on failure
229 */
230
231 PCRE2POSIX_EXP_DEFN int PCRE2_CALL_CONVENTION
regcomp(regex_t * preg,const char * pattern,int cflags)232 regcomp(regex_t *preg, const char *pattern, int cflags)
233 {
234 PCRE2_SIZE erroffset;
235 PCRE2_SIZE patlen;
236 int errorcode;
237 int options = 0;
238 int re_nsub = 0;
239
240 patlen = ((cflags & REG_PEND) != 0)? (PCRE2_SIZE)(preg->re_endp - pattern) :
241 PCRE2_ZERO_TERMINATED;
242
243 if ((cflags & REG_ICASE) != 0) options |= PCRE2_CASELESS;
244 if ((cflags & REG_NEWLINE) != 0) options |= PCRE2_MULTILINE;
245 if ((cflags & REG_DOTALL) != 0) options |= PCRE2_DOTALL;
246 if ((cflags & REG_NOSPEC) != 0) options |= PCRE2_LITERAL;
247 if ((cflags & REG_UTF) != 0) options |= PCRE2_UTF;
248 if ((cflags & REG_UCP) != 0) options |= PCRE2_UCP;
249 if ((cflags & REG_UNGREEDY) != 0) options |= PCRE2_UNGREEDY;
250
251 preg->re_cflags = cflags;
252 preg->re_pcre2_code = pcre2_compile((PCRE2_SPTR)pattern, patlen, options,
253 &errorcode, &erroffset, NULL);
254 preg->re_erroffset = erroffset;
255
256 if (preg->re_pcre2_code == NULL)
257 {
258 unsigned int i;
259
260 /* A negative value is a UTF error; otherwise all error codes are greater
261 than COMPILE_ERROR_BASE, but check, just in case. */
262
263 if (errorcode < COMPILE_ERROR_BASE) return REG_BADPAT;
264 errorcode -= COMPILE_ERROR_BASE;
265
266 if (errorcode < (int)(sizeof(eint1)/sizeof(const int)))
267 return eint1[errorcode];
268 for (i = 0; i < sizeof(eint2)/sizeof(const int); i += 2)
269 if (errorcode == eint2[i]) return eint2[i+1];
270 return REG_BADPAT;
271 }
272
273 (void)pcre2_pattern_info((const pcre2_code *)preg->re_pcre2_code,
274 PCRE2_INFO_CAPTURECOUNT, &re_nsub);
275 preg->re_nsub = (size_t)re_nsub;
276 preg->re_match_data = pcre2_match_data_create(re_nsub + 1, NULL);
277
278 if (preg->re_match_data == NULL)
279 {
280 pcre2_code_free(preg->re_pcre2_code);
281 return REG_ESPACE;
282 }
283
284 return 0;
285 }
286
287
288
289 /*************************************************
290 * Match a regular expression *
291 *************************************************/
292
293 /* A suitable match_data block, large enough to hold all possible captures, was
294 obtained when the pattern was compiled, to save having to allocate and free it
295 for each match. If REG_NOSUB was specified at compile time, the nmatch and
296 pmatch arguments are ignored, and the only result is yes/no/error. */
297
298 PCRE2POSIX_EXP_DEFN int PCRE2_CALL_CONVENTION
regexec(const regex_t * preg,const char * string,size_t nmatch,regmatch_t pmatch[],int eflags)299 regexec(const regex_t *preg, const char *string, size_t nmatch,
300 regmatch_t pmatch[], int eflags)
301 {
302 int rc, so, eo;
303 int options = 0;
304 pcre2_match_data *md = (pcre2_match_data *)preg->re_match_data;
305
306 if ((eflags & REG_NOTBOL) != 0) options |= PCRE2_NOTBOL;
307 if ((eflags & REG_NOTEOL) != 0) options |= PCRE2_NOTEOL;
308 if ((eflags & REG_NOTEMPTY) != 0) options |= PCRE2_NOTEMPTY;
309
310 ((regex_t *)preg)->re_erroffset = (size_t)(-1); /* Only has meaning after compile */
311
312 /* When REG_NOSUB was specified, or if no vector has been passed in which to
313 put captured strings, ensure that nmatch is zero. This will stop any attempt to
314 write to pmatch. */
315
316 if ((preg->re_cflags & REG_NOSUB) != 0 || pmatch == NULL) nmatch = 0;
317
318 /* REG_STARTEND is a BSD extension, to allow for non-NUL-terminated strings.
319 The man page from OS X says "REG_STARTEND affects only the location of the
320 string, not how it is matched". That is why the "so" value is used to bump the
321 start location rather than being passed as a PCRE2 "starting offset". */
322
323 if ((eflags & REG_STARTEND) != 0)
324 {
325 if (pmatch == NULL) return REG_INVARG;
326 so = pmatch[0].rm_so;
327 eo = pmatch[0].rm_eo;
328 }
329 else
330 {
331 so = 0;
332 eo = (int)strlen(string);
333 }
334
335 rc = pcre2_match((const pcre2_code *)preg->re_pcre2_code,
336 (PCRE2_SPTR)string + so, (eo - so), 0, options, md, NULL);
337
338 /* Successful match */
339
340 if (rc >= 0)
341 {
342 size_t i;
343 PCRE2_SIZE *ovector = pcre2_get_ovector_pointer(md);
344 if ((size_t)rc > nmatch) rc = (int)nmatch;
345 for (i = 0; i < (size_t)rc; i++)
346 {
347 pmatch[i].rm_so = (ovector[i*2] == PCRE2_UNSET)? -1 :
348 (int)(ovector[i*2] + so);
349 pmatch[i].rm_eo = (ovector[i*2+1] == PCRE2_UNSET)? -1 :
350 (int)(ovector[i*2+1] + so);
351 }
352 for (; i < nmatch; i++) pmatch[i].rm_so = pmatch[i].rm_eo = -1;
353 return 0;
354 }
355
356 /* Unsuccessful match */
357
358 if (rc <= PCRE2_ERROR_UTF8_ERR1 && rc >= PCRE2_ERROR_UTF8_ERR21)
359 return REG_INVARG;
360
361 switch(rc)
362 {
363 default: return REG_ASSERT;
364 case PCRE2_ERROR_BADMODE: return REG_INVARG;
365 case PCRE2_ERROR_BADMAGIC: return REG_INVARG;
366 case PCRE2_ERROR_BADOPTION: return REG_INVARG;
367 case PCRE2_ERROR_BADUTFOFFSET: return REG_INVARG;
368 case PCRE2_ERROR_MATCHLIMIT: return REG_ESPACE;
369 case PCRE2_ERROR_NOMATCH: return REG_NOMATCH;
370 case PCRE2_ERROR_NOMEMORY: return REG_ESPACE;
371 case PCRE2_ERROR_NULL: return REG_INVARG;
372 }
373 }
374
375 /* End of pcre2posix.c */
376