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 Written by: Philip Hazel <ph10@cam.ac.uk>
12 Copyright (c) 1997-2001 University of Cambridge
14 -----------------------------------------------------------------------------
15 Permission is granted to anyone to use this software for any purpose on any
16 computer system, and to redistribute it freely, subject to the following
19 1. This software is distributed in the hope that it will be useful,
20 but WITHOUT ANY WARRANTY; without even the implied warranty of
21 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
23 2. The origin of this software must not be misrepresented, either by
24 explicit claim or by omission.
26 3. Altered versions must be plainly marked as such, and must not be
27 misrepresented as being the original software.
29 4. If PCRE is embedded in any software that is released under the GNU
30 General Purpose Licence (GPL), then the terms of that licence shall
31 supersede any condition above with which it is incompatible.
32 -----------------------------------------------------------------------------
35 /* This header contains definitions that are shared between the different
36 modules, but which are not relevant to the outside. */
38 /* Get the definitions provided by running "configure" */
42 /* To cope with SunOS4 and other systems that lack memmove() but have bcopy(),
43 define a macro for memmove() if HAVE_MEMMOVE is false, provided that HAVE_BCOPY
44 is set. Otherwise, include an emulating function for those systems that have
45 neither (there some non-Unix environments where this is the case). This assumes
46 that all calls to memmove are moving strings upwards in store, which is the
50 #undef memmove /* some systems may have a macro */
52 #define memmove(a, b, c) bcopy(b, a, c)
55 pcre_memmove(unsigned char *dest, const unsigned char *src, size_t n)
60 for (i = 0; i < n; ++i) *(--dest) = *(--src);
62 #define memmove(a, b, c) pcre_memmove(a, b, c)
66 /* Standard C headers plus the external interface definition */
76 /* In case there is no definition of offsetof() provided - though any proper
77 Standard C system should have one. */
80 #define offsetof(p_type,field) ((size_t)&(((p_type *)0)->field))
83 /* These are the public options that can change during matching. */
85 #define PCRE_IMS (PCRE_CASELESS|PCRE_MULTILINE|PCRE_DOTALL)
87 /* Private options flags start at the most significant end of the four bytes,
88 but skip the top bit so we can use ints for convenience without getting tangled
89 with negative values. The public options defined in pcre.h start at the least
90 significant end. Make sure they don't overlap, though now that we have expanded
91 to four bytes there is plenty of space. */
93 #define PCRE_FIRSTSET 0x40000000 /* first_char is set */
94 #define PCRE_REQCHSET 0x20000000 /* req_char is set */
95 #define PCRE_STARTLINE 0x10000000 /* start after \n for multiline */
96 #define PCRE_INGROUP 0x08000000 /* compiling inside a group */
97 #define PCRE_ICHANGED 0x04000000 /* i option changes within regex */
99 /* Options for the "extra" block produced by pcre_study(). */
101 #define PCRE_STUDY_MAPPED 0x01 /* a map of starting chars exists */
103 /* Masks for identifying the public options which are permitted at compile
104 time, run time or study time, respectively. */
106 #define PUBLIC_OPTIONS \
107 (PCRE_CASELESS|PCRE_EXTENDED|PCRE_ANCHORED|PCRE_MULTILINE| \
108 PCRE_DOTALL|PCRE_DOLLAR_ENDONLY|PCRE_EXTRA|PCRE_UNGREEDY|PCRE_UTF8)
110 #define PUBLIC_EXEC_OPTIONS \
111 (PCRE_ANCHORED|PCRE_NOTBOL|PCRE_NOTEOL|PCRE_NOTEMPTY)
113 #define PUBLIC_STUDY_OPTIONS 0 /* None defined */
115 /* Magic number to provide a small check against being handed junk. */
117 #define MAGIC_NUMBER 0x50435245UL /* 'PCRE' */
119 /* Miscellaneous definitions */
126 /* Escape items that are just an encoding of a particular data value. Note that
127 ESC_N is defined as yet another macro, which is set in config.h to either \n
128 (the default) or \r (which some people want). */
139 #define ESC_N NEWLINE
150 /* These are escaped items that aren't just an encoding of a particular data
151 value such as \n. They must have non-zero values, as check_escape() returns
152 their negation. Also, they must appear in the same order as in the opcode
153 definitions below, up to ESC_z. The final one must be ESC_REF as subsequent
154 values are used for \1, \2, \3, etc. There is a test in the code for an escape
155 greater than ESC_b and less than ESC_Z to detect the types that may be
156 repeated. If any new escapes are put in-between that don't consume a character,
157 that code will have to change. */
159 enum { ESC_A = 1, ESC_B, ESC_b, ESC_D, ESC_d, ESC_S, ESC_s, ESC_W, ESC_w,
160 ESC_Z, ESC_z, ESC_REF };
162 /* Opcode table: OP_BRA must be last, as all values >= it are used for brackets
163 that extract substrings. Starting from 1 (i.e. after OP_END), the values up to
164 OP_EOD must correspond in order to the list of escapes immediately above. */
167 OP_END, /* End of pattern */
169 /* Values corresponding to backslashed metacharacters */
171 OP_SOD, /* Start of data: \A */
172 OP_NOT_WORD_BOUNDARY, /* \B */
173 OP_WORD_BOUNDARY, /* \b */
174 OP_NOT_DIGIT, /* \D */
176 OP_NOT_WHITESPACE, /* \S */
177 OP_WHITESPACE, /* \s */
178 OP_NOT_WORDCHAR, /* \W */
179 OP_WORDCHAR, /* \w */
180 OP_EODN, /* End of data or \n at end of data: \Z. */
181 OP_EOD, /* End of data: \z */
183 OP_OPT, /* Set runtime options */
184 OP_CIRC, /* Start of line - varies with multiline switch */
185 OP_DOLL, /* End of line - varies with multiline switch */
186 OP_ANY, /* Match any character */
187 OP_CHARS, /* Match string of characters */
188 OP_NOT, /* Match anything but the following char */
190 OP_STAR, /* The maximizing and minimizing versions of */
191 OP_MINSTAR, /* all these opcodes must come in pairs, with */
192 OP_PLUS, /* the minimizing one second. */
193 OP_MINPLUS, /* This first set applies to single characters */
196 OP_UPTO, /* From 0 to n matches */
198 OP_EXACT, /* Exactly n matches */
200 OP_NOTSTAR, /* The maximizing and minimizing versions of */
201 OP_NOTMINSTAR, /* all these opcodes must come in pairs, with */
202 OP_NOTPLUS, /* the minimizing one second. */
203 OP_NOTMINPLUS, /* This first set applies to "not" single characters */
206 OP_NOTUPTO, /* From 0 to n matches */
208 OP_NOTEXACT, /* Exactly n matches */
210 OP_TYPESTAR, /* The maximizing and minimizing versions of */
211 OP_TYPEMINSTAR, /* all these opcodes must come in pairs, with */
212 OP_TYPEPLUS, /* the minimizing one second. These codes must */
213 OP_TYPEMINPLUS, /* be in exactly the same order as those above. */
214 OP_TYPEQUERY, /* This set applies to character types such as \d */
216 OP_TYPEUPTO, /* From 0 to n matches */
218 OP_TYPEEXACT, /* Exactly n matches */
220 OP_CRSTAR, /* The maximizing and minimizing versions of */
221 OP_CRMINSTAR, /* all these opcodes must come in pairs, with */
222 OP_CRPLUS, /* the minimizing one second. These codes must */
223 OP_CRMINPLUS, /* be in exactly the same order as those above. */
224 OP_CRQUERY, /* These are for character classes and back refs */
226 OP_CRRANGE, /* These are different to the three seta above. */
229 OP_CLASS, /* Match a character class */
230 OP_REF, /* Match a back reference */
231 OP_RECURSE, /* Match this pattern recursively */
233 OP_ALT, /* Start of alternation */
234 OP_KET, /* End of group that doesn't have an unbounded repeat */
235 OP_KETRMAX, /* These two must remain together and in this */
236 OP_KETRMIN, /* order. They are for groups the repeat for ever. */
238 /* The assertions must come before ONCE and COND */
240 OP_ASSERT, /* Positive lookahead */
241 OP_ASSERT_NOT, /* Negative lookahead */
242 OP_ASSERTBACK, /* Positive lookbehind */
243 OP_ASSERTBACK_NOT, /* Negative lookbehind */
244 OP_REVERSE, /* Move pointer back - used in lookbehind assertions */
246 /* ONCE and COND must come after the assertions, with ONCE first, as there's
247 a test for >= ONCE for a subpattern that isn't an assertion. */
249 OP_ONCE, /* Once matched, don't back up into the subpattern */
250 OP_COND, /* Conditional group */
251 OP_CREF, /* Used to hold an extraction string number (cond ref) */
253 OP_BRAZERO, /* These two must remain together and in this */
254 OP_BRAMINZERO, /* order. */
256 OP_BRANUMBER, /* Used for extracting brackets whose number is greater
257 than can fit into an opcode. */
259 OP_BRA /* This and greater values are used for brackets that
260 extract substrings up to a basic limit. After that,
261 use is made of OP_BRANUMBER. */
264 /* The highest extraction number before we have to start using additional
265 bytes. (Originally PCRE didn't have support for extraction counts highter than
266 this number.) The value is limited by the number of opcodes left after OP_BRA,
267 i.e. 255 - OP_BRA. We actually set it a bit lower to leave room for additional
270 #define EXTRACT_BASIC_MAX 150
272 /* The texts of compile-time error messages are defined as macros here so that
273 they can be accessed by the POSIX wrapper and converted into error codes. Yes,
274 I could have used error codes in the first place, but didn't feel like changing
275 just to accommodate the POSIX wrapper. */
277 #define ERR1 "\\ at end of pattern"
278 #define ERR2 "\\c at end of pattern"
279 #define ERR3 "unrecognized character follows \\"
280 #define ERR4 "numbers out of order in {} quantifier"
281 #define ERR5 "number too big in {} quantifier"
282 #define ERR6 "missing terminating ] for character class"
283 #define ERR7 "invalid escape sequence in character class"
284 #define ERR8 "range out of order in character class"
285 #define ERR9 "nothing to repeat"
286 #define ERR10 "operand of unlimited repeat could match the empty string"
287 #define ERR11 "internal error: unexpected repeat"
288 #define ERR12 "unrecognized character after (?"
289 #define ERR13 "unused error"
290 #define ERR14 "missing )"
291 #define ERR15 "back reference to non-existent subpattern"
292 #define ERR16 "erroffset passed as NULL"
293 #define ERR17 "unknown option bit(s) set"
294 #define ERR18 "missing ) after comment"
295 #define ERR19 "parentheses nested too deeply"
296 #define ERR20 "regular expression too large"
297 #define ERR21 "failed to get memory"
298 #define ERR22 "unmatched parentheses"
299 #define ERR23 "internal error: code overflow"
300 #define ERR24 "unrecognized character after (?<"
301 #define ERR25 "lookbehind assertion is not fixed length"
302 #define ERR26 "malformed number after (?("
303 #define ERR27 "conditional group contains more than two branches"
304 #define ERR28 "assertion expected after (?("
305 #define ERR29 "(?p must be followed by )"
306 #define ERR30 "unknown POSIX class name"
307 #define ERR31 "POSIX collating elements are not supported"
308 #define ERR32 "this version of PCRE is not compiled with PCRE_UTF8 support"
309 #define ERR33 "characters with values > 255 are not yet supported in classes"
310 #define ERR34 "character value in \\x{...} sequence is too large"
311 #define ERR35 "invalid condition (?(0)"
313 /* All character handling must be done as unsigned characters. Otherwise there
314 are problems with top-bit-set characters and functions such as isspace().
315 However, we leave the interface to the outside world as char *, because that
316 should make things easier for callers. We define a short type for unsigned char
317 to save lots of typing. I tried "uchar", but it causes problems on Digital
318 Unix, where it is defined in sys/types, so use "uschar" instead. */
320 typedef unsigned char uschar;
322 /* The real format of the start of the pcre block; the actual code vector
323 runs on as long as necessary after the end. */
325 typedef struct real_pcre {
326 unsigned long int magic_number;
328 const unsigned char *tables;
329 unsigned long int options;
330 unsigned short int top_bracket;
331 unsigned short int top_backref;
337 /* The real format of the extra block returned by pcre_study(). */
339 typedef struct real_pcre_extra {
341 uschar start_bits[32];
345 /* Structure for passing "static" information around between the functions
346 doing the compiling, so that they are thread-safe. */
348 typedef struct compile_data {
349 const uschar *lcc; /* Points to lower casing table */
350 const uschar *fcc; /* Points to case-flipping table */
351 const uschar *cbits; /* Points to character type table */
352 const uschar *ctypes; /* Points to table of type maps */
355 /* Structure for passing "static" information around between the functions
356 doing the matching, so that they are thread-safe. */
358 typedef struct match_data {
359 int errorcode; /* As it says */
360 int *offset_vector; /* Offset vector */
361 int offset_end; /* One past the end */
362 int offset_max; /* The maximum usable for return data */
363 const uschar *lcc; /* Points to lower casing table */
364 const uschar *ctypes; /* Points to table of type maps */
365 BOOL offset_overflow; /* Set if too many extractions */
366 BOOL notbol; /* NOTBOL flag */
367 BOOL noteol; /* NOTEOL flag */
368 BOOL utf8; /* UTF8 flag */
369 BOOL endonly; /* Dollar not before final \n */
370 BOOL notempty; /* Empty string match not wanted */
371 const uschar *start_pattern; /* For use when recursing */
372 const uschar *start_subject; /* Start of the subject string */
373 const uschar *end_subject; /* End of the subject string */
374 const uschar *start_match; /* Start of this match attempt */
375 const uschar *end_match_ptr; /* Subject position at end match */
376 int end_offset_top; /* Highwater mark at end of match */
379 /* Bit definitions for entries in the pcre_ctypes table. */
381 #define ctype_space 0x01
382 #define ctype_letter 0x02
383 #define ctype_digit 0x04
384 #define ctype_xdigit 0x08
385 #define ctype_word 0x10 /* alphameric or '_' */
386 #define ctype_meta 0x80 /* regexp meta char or zero (end pattern) */
388 /* Offsets for the bitmap tables in pcre_cbits. Each table contains a set
389 of bits for a class map. Some classes are built by combining these tables. */
391 #define cbit_space 0 /* [:space:] or \s */
392 #define cbit_xdigit 32 /* [:xdigit:] */
393 #define cbit_digit 64 /* [:digit:] or \d */
394 #define cbit_upper 96 /* [:upper:] */
395 #define cbit_lower 128 /* [:lower:] */
396 #define cbit_word 160 /* [:word:] or \w */
397 #define cbit_graph 192 /* [:graph:] */
398 #define cbit_print 224 /* [:print:] */
399 #define cbit_punct 256 /* [:punct:] */
400 #define cbit_cntrl 288 /* [:cntrl:] */
401 #define cbit_length 320 /* Length of the cbits table */
403 /* Offsets of the various tables from the base tables pointer, and
407 #define fcc_offset 256
408 #define cbits_offset 512
409 #define ctypes_offset (cbits_offset + cbit_length)
410 #define tables_length (ctypes_offset + 256)
412 /* End of internal.h */