xref: /PHP-5.6/ext/pcre/pcrelib/pcreposix.c (revision 23917b45)
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) 1997-2014 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 #ifdef HAVE_CONFIG_H
46 #include "config.h"
47 #endif
48 
49 
50 /* Ensure that the PCREPOSIX_EXP_xxx macros are set appropriately for
51 compiling these functions. This must come before including pcreposix.h, where
52 they are set for an application (using these functions) if they have not
53 previously been set. */
54 
55 #if defined(_WIN32) && !defined(PCRE_STATIC)
56 #  define PCREPOSIX_EXP_DECL extern __declspec(dllexport)
57 #  define PCREPOSIX_EXP_DEFN __declspec(dllexport)
58 #endif
59 
60 /* We include pcre.h before pcre_internal.h so that the PCRE library functions
61 are declared as "import" for Windows by defining PCRE_EXP_DECL as "import".
62 This is needed even though pcre_internal.h itself includes pcre.h, because it
63 does so after it has set PCRE_EXP_DECL to "export" if it is not already set. */
64 
65 #include "pcre.h"
66 #include "pcre_internal.h"
67 #include "pcreposix.h"
68 
69 
70 /* Table to translate PCRE compile time error codes into POSIX error codes. */
71 
72 static const int eint[] = {
73   0,           /* no error */
74   REG_EESCAPE, /* \ at end of pattern */
75   REG_EESCAPE, /* \c at end of pattern */
76   REG_EESCAPE, /* unrecognized character follows \ */
77   REG_BADBR,   /* numbers out of order in {} quantifier */
78   /* 5 */
79   REG_BADBR,   /* number too big in {} quantifier */
80   REG_EBRACK,  /* missing terminating ] for character class */
81   REG_ECTYPE,  /* invalid escape sequence in character class */
82   REG_ERANGE,  /* range out of order in character class */
83   REG_BADRPT,  /* nothing to repeat */
84   /* 10 */
85   REG_BADRPT,  /* operand of unlimited repeat could match the empty string */
86   REG_ASSERT,  /* internal error: unexpected repeat */
87   REG_BADPAT,  /* unrecognized character after (? */
88   REG_BADPAT,  /* POSIX named classes are supported only within a class */
89   REG_EPAREN,  /* missing ) */
90   /* 15 */
91   REG_ESUBREG, /* reference to non-existent subpattern */
92   REG_INVARG,  /* erroffset passed as NULL */
93   REG_INVARG,  /* unknown option bit(s) set */
94   REG_EPAREN,  /* missing ) after comment */
95   REG_ESIZE,   /* parentheses nested too deeply */
96   /* 20 */
97   REG_ESIZE,   /* regular expression too large */
98   REG_ESPACE,  /* failed to get memory */
99   REG_EPAREN,  /* unmatched parentheses */
100   REG_ASSERT,  /* internal error: code overflow */
101   REG_BADPAT,  /* unrecognized character after (?< */
102   /* 25 */
103   REG_BADPAT,  /* lookbehind assertion is not fixed length */
104   REG_BADPAT,  /* malformed number or name after (?( */
105   REG_BADPAT,  /* conditional group contains more than two branches */
106   REG_BADPAT,  /* assertion expected after (?( */
107   REG_BADPAT,  /* (?R or (?[+-]digits must be followed by ) */
108   /* 30 */
109   REG_ECTYPE,  /* unknown POSIX class name */
110   REG_BADPAT,  /* POSIX collating elements are not supported */
111   REG_INVARG,  /* this version of PCRE is not compiled with PCRE_UTF8 support */
112   REG_BADPAT,  /* spare error */
113   REG_BADPAT,  /* character value in \x{} or \o{} is too large */
114   /* 35 */
115   REG_BADPAT,  /* invalid condition (?(0) */
116   REG_BADPAT,  /* \C not allowed in lookbehind assertion */
117   REG_EESCAPE, /* PCRE does not support \L, \l, \N, \U, or \u */
118   REG_BADPAT,  /* number after (?C is > 255 */
119   REG_BADPAT,  /* closing ) for (?C expected */
120   /* 40 */
121   REG_BADPAT,  /* recursive call could loop indefinitely */
122   REG_BADPAT,  /* unrecognized character after (?P */
123   REG_BADPAT,  /* syntax error in subpattern name (missing terminator) */
124   REG_BADPAT,  /* two named subpatterns have the same name */
125   REG_BADPAT,  /* invalid UTF-8 string */
126   /* 45 */
127   REG_BADPAT,  /* support for \P, \p, and \X has not been compiled */
128   REG_BADPAT,  /* malformed \P or \p sequence */
129   REG_BADPAT,  /* unknown property name after \P or \p */
130   REG_BADPAT,  /* subpattern name is too long (maximum 32 characters) */
131   REG_BADPAT,  /* too many named subpatterns (maximum 10,000) */
132   /* 50 */
133   REG_BADPAT,  /* repeated subpattern is too long */
134   REG_BADPAT,  /* octal value is greater than \377 (not in UTF-8 mode) */
135   REG_BADPAT,  /* internal error: overran compiling workspace */
136   REG_BADPAT,  /* internal error: previously-checked referenced subpattern not found */
137   REG_BADPAT,  /* DEFINE group contains more than one branch */
138   /* 55 */
139   REG_BADPAT,  /* repeating a DEFINE group is not allowed */
140   REG_INVARG,  /* inconsistent NEWLINE options */
141   REG_BADPAT,  /* \g is not followed followed by an (optionally braced) non-zero number */
142   REG_BADPAT,  /* a numbered reference must not be zero */
143   REG_BADPAT,  /* an argument is not allowed for (*ACCEPT), (*FAIL), or (*COMMIT) */
144   /* 60 */
145   REG_BADPAT,  /* (*VERB) not recognized */
146   REG_BADPAT,  /* number is too big */
147   REG_BADPAT,  /* subpattern name expected */
148   REG_BADPAT,  /* digit expected after (?+ */
149   REG_BADPAT,  /* ] is an invalid data character in JavaScript compatibility mode */
150   /* 65 */
151   REG_BADPAT,  /* different names for subpatterns of the same number are not allowed */
152   REG_BADPAT,  /* (*MARK) must have an argument */
153   REG_INVARG,  /* this version of PCRE is not compiled with PCRE_UCP support */
154   REG_BADPAT,  /* \c must be followed by an ASCII character */
155   REG_BADPAT,  /* \k is not followed by a braced, angle-bracketed, or quoted name */
156   /* 70 */
157   REG_BADPAT,  /* internal error: unknown opcode in find_fixedlength() */
158   REG_BADPAT,  /* \N is not supported in a class */
159   REG_BADPAT,  /* too many forward references */
160   REG_BADPAT,  /* disallowed UTF-8/16/32 code point (>= 0xd800 && <= 0xdfff) */
161   REG_BADPAT,  /* invalid UTF-16 string (should not occur) */
162   /* 75 */
163   REG_BADPAT,  /* overlong MARK name */
164   REG_BADPAT,  /* character value in \u.... sequence is too large */
165   REG_BADPAT,  /* invalid UTF-32 string (should not occur) */
166   REG_BADPAT,  /* setting UTF is disabled by the application */
167   REG_BADPAT,  /* non-hex character in \\x{} (closing brace missing?) */
168   /* 80 */
169   REG_BADPAT,  /* non-octal character in \o{} (closing brace missing?) */
170   REG_BADPAT,  /* missing opening brace after \o */
171   REG_BADPAT,  /* parentheses too deeply nested */
172   REG_BADPAT,  /* invalid range in character class */
173   REG_BADPAT,  /* group name must start with a non-digit */
174   /* 85 */
175   REG_BADPAT,  /* parentheses too deeply nested (stack check) */
176   REG_BADPAT   /* missing digits in \x{} or \o{} */
177 };
178 
179 /* Table of texts corresponding to POSIX error codes */
180 
181 static const char *const pstring[] = {
182   "",                                /* Dummy for value 0 */
183   "internal error",                  /* REG_ASSERT */
184   "invalid repeat counts in {}",     /* BADBR      */
185   "pattern error",                   /* BADPAT     */
186   "? * + invalid",                   /* BADRPT     */
187   "unbalanced {}",                   /* EBRACE     */
188   "unbalanced []",                   /* EBRACK     */
189   "collation error - not relevant",  /* ECOLLATE   */
190   "bad class",                       /* ECTYPE     */
191   "bad escape sequence",             /* EESCAPE    */
192   "empty expression",                /* EMPTY      */
193   "unbalanced ()",                   /* EPAREN     */
194   "bad range inside []",             /* ERANGE     */
195   "expression too big",              /* ESIZE      */
196   "failed to get memory",            /* ESPACE     */
197   "bad back reference",              /* ESUBREG    */
198   "bad argument",                    /* INVARG     */
199   "match failed"                     /* NOMATCH    */
200 };
201 
202 
203 
204 
205 /*************************************************
206 *          Translate error code to string        *
207 *************************************************/
208 
209 PCREPOSIX_EXP_DEFN size_t PCRE_CALL_CONVENTION
regerror(int errcode,const regex_t * preg,char * errbuf,size_t errbuf_size)210 regerror(int errcode, const regex_t *preg, char *errbuf, size_t errbuf_size)
211 {
212 const char *message, *addmessage;
213 size_t length, addlength;
214 
215 message = (errcode >= (int)(sizeof(pstring)/sizeof(char *)))?
216   "unknown error code" : pstring[errcode];
217 length = strlen(message) + 1;
218 
219 addmessage = " at offset ";
220 addlength = (preg != NULL && (int)preg->re_erroffset != -1)?
221   strlen(addmessage) + 6 : 0;
222 
223 if (errbuf_size > 0)
224   {
225   if (addlength > 0 && errbuf_size >= length + addlength)
226     sprintf(errbuf, "%s%s%-6d", message, addmessage, (int)preg->re_erroffset);
227   else
228     {
229     strncpy(errbuf, message, errbuf_size - 1);
230     errbuf[errbuf_size-1] = 0;
231     }
232   }
233 
234 return length + addlength;
235 }
236 
237 
238 
239 
240 /*************************************************
241 *           Free store held by a regex           *
242 *************************************************/
243 
244 PCREPOSIX_EXP_DEFN void PCRE_CALL_CONVENTION
regfree(regex_t * preg)245 regfree(regex_t *preg)
246 {
247 (PUBL(free))(preg->re_pcre);
248 }
249 
250 
251 
252 
253 /*************************************************
254 *            Compile a regular expression        *
255 *************************************************/
256 
257 /*
258 Arguments:
259   preg        points to a structure for recording the compiled expression
260   pattern     the pattern to compile
261   cflags      compilation flags
262 
263 Returns:      0 on success
264               various non-zero codes on failure
265 */
266 
267 PCREPOSIX_EXP_DEFN int PCRE_CALL_CONVENTION
regcomp(regex_t * preg,const char * pattern,int cflags)268 regcomp(regex_t *preg, const char *pattern, int cflags)
269 {
270 const char *errorptr;
271 int erroffset;
272 int errorcode;
273 int options = 0;
274 int re_nsub = 0;
275 
276 if ((cflags & REG_ICASE) != 0)    options |= PCRE_CASELESS;
277 if ((cflags & REG_NEWLINE) != 0)  options |= PCRE_MULTILINE;
278 if ((cflags & REG_DOTALL) != 0)   options |= PCRE_DOTALL;
279 if ((cflags & REG_NOSUB) != 0)    options |= PCRE_NO_AUTO_CAPTURE;
280 if ((cflags & REG_UTF8) != 0)     options |= PCRE_UTF8;
281 if ((cflags & REG_UCP) != 0)      options |= PCRE_UCP;
282 if ((cflags & REG_UNGREEDY) != 0) options |= PCRE_UNGREEDY;
283 
284 preg->re_pcre = pcre_compile2(pattern, options, &errorcode, &errorptr,
285   &erroffset, NULL);
286 preg->re_erroffset = erroffset;
287 
288 /* Safety: if the error code is too big for the translation vector (which
289 should not happen, but we all make mistakes), return REG_BADPAT. */
290 
291 if (preg->re_pcre == NULL)
292   {
293   return (errorcode < (int)(sizeof(eint)/sizeof(const int)))?
294     eint[errorcode] : REG_BADPAT;
295   }
296 
297 (void)pcre_fullinfo((const pcre *)preg->re_pcre, NULL, PCRE_INFO_CAPTURECOUNT,
298   &re_nsub);
299 preg->re_nsub = (size_t)re_nsub;
300 return 0;
301 }
302 
303 
304 
305 
306 /*************************************************
307 *              Match a regular expression        *
308 *************************************************/
309 
310 /* Unfortunately, PCRE requires 3 ints of working space for each captured
311 substring, so we have to get and release working store instead of just using
312 the POSIX structures as was done in earlier releases when PCRE needed only 2
313 ints. However, if the number of possible capturing brackets is small, use a
314 block of store on the stack, to reduce the use of malloc/free. The threshold is
315 in a macro that can be changed at configure time.
316 
317 If REG_NOSUB was specified at compile time, the PCRE_NO_AUTO_CAPTURE flag will
318 be set. When this is the case, the nmatch and pmatch arguments are ignored, and
319 the only result is yes/no/error. */
320 
321 PCREPOSIX_EXP_DEFN int PCRE_CALL_CONVENTION
regexec(const regex_t * preg,const char * string,size_t nmatch,regmatch_t pmatch[],int eflags)322 regexec(const regex_t *preg, const char *string, size_t nmatch,
323   regmatch_t pmatch[], int eflags)
324 {
325 int rc, so, eo;
326 int options = 0;
327 int *ovector = NULL;
328 int small_ovector[POSIX_MALLOC_THRESHOLD * 3];
329 BOOL allocated_ovector = FALSE;
330 BOOL nosub =
331   (REAL_PCRE_OPTIONS((const pcre *)preg->re_pcre) & PCRE_NO_AUTO_CAPTURE) != 0;
332 
333 if ((eflags & REG_NOTBOL) != 0) options |= PCRE_NOTBOL;
334 if ((eflags & REG_NOTEOL) != 0) options |= PCRE_NOTEOL;
335 if ((eflags & REG_NOTEMPTY) != 0) options |= PCRE_NOTEMPTY;
336 
337 ((regex_t *)preg)->re_erroffset = (size_t)(-1);  /* Only has meaning after compile */
338 
339 /* When no string data is being returned, or no vector has been passed in which
340 to put it, ensure that nmatch is zero. Otherwise, ensure the vector for holding
341 the return data is large enough. */
342 
343 if (nosub || pmatch == NULL) nmatch = 0;
344 
345 else if (nmatch > 0)
346   {
347   if (nmatch <= POSIX_MALLOC_THRESHOLD)
348     {
349     ovector = &(small_ovector[0]);
350     }
351   else
352     {
353     if (nmatch > INT_MAX/(sizeof(int) * 3)) return REG_ESPACE;
354     ovector = (int *)malloc(sizeof(int) * nmatch * 3);
355     if (ovector == NULL) return REG_ESPACE;
356     allocated_ovector = TRUE;
357     }
358   }
359 
360 /* REG_STARTEND is a BSD extension, to allow for non-NUL-terminated strings.
361 The man page from OS X says "REG_STARTEND affects only the location of the
362 string, not how it is matched". That is why the "so" value is used to bump the
363 start location rather than being passed as a PCRE "starting offset". */
364 
365 if ((eflags & REG_STARTEND) != 0)
366   {
367   so = pmatch[0].rm_so;
368   eo = pmatch[0].rm_eo;
369   }
370 else
371   {
372   so = 0;
373   eo = (int)strlen(string);
374   }
375 
376 rc = pcre_exec((const pcre *)preg->re_pcre, NULL, string + so, (eo - so),
377   0, options, ovector, (int)(nmatch * 3));
378 
379 if (rc == 0) rc = (int)nmatch;    /* All captured slots were filled in */
380 
381 /* Successful match */
382 
383 if (rc >= 0)
384   {
385   size_t i;
386   if (!nosub)
387     {
388     for (i = 0; i < (size_t)rc; i++)
389       {
390       pmatch[i].rm_so = ovector[i*2];
391       pmatch[i].rm_eo = ovector[i*2+1];
392       }
393     if (allocated_ovector) free(ovector);
394     for (; i < nmatch; i++) pmatch[i].rm_so = pmatch[i].rm_eo = -1;
395     }
396   return 0;
397   }
398 
399 /* Unsuccessful match */
400 
401 if (allocated_ovector) free(ovector);
402 switch(rc)
403   {
404 /* ========================================================================== */
405   /* These cases are never obeyed. This is a fudge that causes a compile-time
406   error if the vector eint, which is indexed by compile-time error number, is
407   not the correct length. It seems to be the only way to do such a check at
408   compile time, as the sizeof() operator does not work in the C preprocessor.
409   As all the PCRE_ERROR_xxx values are negative, we can use 0 and 1. */
410 
411   case 0:
412   case (sizeof(eint)/sizeof(int) == ERRCOUNT):
413   return REG_ASSERT;
414 /* ========================================================================== */
415 
416   case PCRE_ERROR_NOMATCH: return REG_NOMATCH;
417   case PCRE_ERROR_NULL: return REG_INVARG;
418   case PCRE_ERROR_BADOPTION: return REG_INVARG;
419   case PCRE_ERROR_BADMAGIC: return REG_INVARG;
420   case PCRE_ERROR_UNKNOWN_NODE: return REG_ASSERT;
421   case PCRE_ERROR_NOMEMORY: return REG_ESPACE;
422   case PCRE_ERROR_MATCHLIMIT: return REG_ESPACE;
423   case PCRE_ERROR_BADUTF8: return REG_INVARG;
424   case PCRE_ERROR_BADUTF8_OFFSET: return REG_INVARG;
425   case PCRE_ERROR_BADMODE: return REG_INVARG;
426   default: return REG_ASSERT;
427   }
428 }
429 
430 /* End of pcreposix.c */
431