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Revision 170 - (show annotations) (download)
Mon Jun 4 11:21:13 2007 UTC (6 years, 10 months ago) by ph10
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File size: 174621 byte(s)
Fix bug in detecting potentially empty groups.

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) 1997-2007 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 contains the external function pcre_compile(), along with
42 supporting internal functions that are not used by other modules. */
43
44
45 #define NLBLOCK cd /* Block containing newline information */
46 #define PSSTART start_pattern /* Field containing processed string start */
47 #define PSEND end_pattern /* Field containing processed string end */
48
49
50 #include "pcre_internal.h"
51
52
53 /* When DEBUG is defined, we need the pcre_printint() function, which is also
54 used by pcretest. DEBUG is not defined when building a production library. */
55
56 #ifdef DEBUG
57 #include "pcre_printint.src"
58 #endif
59
60
61 /*************************************************
62 * Code parameters and static tables *
63 *************************************************/
64
65 /* This value specifies the size of stack workspace that is used during the
66 first pre-compile phase that determines how much memory is required. The regex
67 is partly compiled into this space, but the compiled parts are discarded as
68 soon as they can be, so that hopefully there will never be an overrun. The code
69 does, however, check for an overrun. The largest amount I've seen used is 218,
70 so this number is very generous.
71
72 The same workspace is used during the second, actual compile phase for
73 remembering forward references to groups so that they can be filled in at the
74 end. Each entry in this list occupies LINK_SIZE bytes, so even when LINK_SIZE
75 is 4 there is plenty of room. */
76
77 #define COMPILE_WORK_SIZE (4096)
78
79
80 /* Table for handling escaped characters in the range '0'-'z'. Positive returns
81 are simple data values; negative values are for special things like \d and so
82 on. Zero means further processing is needed (for things like \x), or the escape
83 is invalid. */
84
85 #ifndef EBCDIC /* This is the "normal" table for ASCII systems */
86 static const short int escapes[] = {
87 0, 0, 0, 0, 0, 0, 0, 0, /* 0 - 7 */
88 0, 0, ':', ';', '<', '=', '>', '?', /* 8 - ? */
89 '@', -ESC_A, -ESC_B, -ESC_C, -ESC_D, -ESC_E, 0, -ESC_G, /* @ - G */
90 0, 0, 0, -ESC_K, 0, 0, 0, 0, /* H - O */
91 -ESC_P, -ESC_Q, -ESC_R, -ESC_S, 0, 0, 0, -ESC_W, /* P - W */
92 -ESC_X, 0, -ESC_Z, '[', '\\', ']', '^', '_', /* X - _ */
93 '`', 7, -ESC_b, 0, -ESC_d, ESC_e, ESC_f, 0, /* ` - g */
94 0, 0, 0, -ESC_k, 0, 0, ESC_n, 0, /* h - o */
95 -ESC_p, 0, ESC_r, -ESC_s, ESC_tee, 0, 0, -ESC_w, /* p - w */
96 0, 0, -ESC_z /* x - z */
97 };
98
99 #else /* This is the "abnormal" table for EBCDIC systems */
100 static const short int escapes[] = {
101 /* 48 */ 0, 0, 0, '.', '<', '(', '+', '|',
102 /* 50 */ '&', 0, 0, 0, 0, 0, 0, 0,
103 /* 58 */ 0, 0, '!', '$', '*', ')', ';', '~',
104 /* 60 */ '-', '/', 0, 0, 0, 0, 0, 0,
105 /* 68 */ 0, 0, '|', ',', '%', '_', '>', '?',
106 /* 70 */ 0, 0, 0, 0, 0, 0, 0, 0,
107 /* 78 */ 0, '`', ':', '#', '@', '\'', '=', '"',
108 /* 80 */ 0, 7, -ESC_b, 0, -ESC_d, ESC_e, ESC_f, 0,
109 /* 88 */ 0, 0, 0, '{', 0, 0, 0, 0,
110 /* 90 */ 0, 0, -ESC_k, 'l', 0, ESC_n, 0, -ESC_p,
111 /* 98 */ 0, ESC_r, 0, '}', 0, 0, 0, 0,
112 /* A0 */ 0, '~', -ESC_s, ESC_tee, 0, 0, -ESC_w, 0,
113 /* A8 */ 0,-ESC_z, 0, 0, 0, '[', 0, 0,
114 /* B0 */ 0, 0, 0, 0, 0, 0, 0, 0,
115 /* B8 */ 0, 0, 0, 0, 0, ']', '=', '-',
116 /* C0 */ '{',-ESC_A, -ESC_B, -ESC_C, -ESC_D,-ESC_E, 0, -ESC_G,
117 /* C8 */ 0, 0, 0, 0, 0, 0, 0, 0,
118 /* D0 */ '}', 0, 0, 0, 0, 0, 0, -ESC_P,
119 /* D8 */-ESC_Q,-ESC_R, 0, 0, 0, 0, 0, 0,
120 /* E0 */ '\\', 0, -ESC_S, 0, 0, 0, -ESC_W, -ESC_X,
121 /* E8 */ 0,-ESC_Z, 0, 0, 0, 0, 0, 0,
122 /* F0 */ 0, 0, 0, 0, 0, 0, 0, 0,
123 /* F8 */ 0, 0, 0, 0, 0, 0, 0, 0
124 };
125 #endif
126
127
128 /* Tables of names of POSIX character classes and their lengths. The list is
129 terminated by a zero length entry. The first three must be alpha, lower, upper,
130 as this is assumed for handling case independence. */
131
132 static const char *const posix_names[] = {
133 "alpha", "lower", "upper",
134 "alnum", "ascii", "blank", "cntrl", "digit", "graph",
135 "print", "punct", "space", "word", "xdigit" };
136
137 static const uschar posix_name_lengths[] = {
138 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 4, 6, 0 };
139
140 /* Table of class bit maps for each POSIX class. Each class is formed from a
141 base map, with an optional addition or removal of another map. Then, for some
142 classes, there is some additional tweaking: for [:blank:] the vertical space
143 characters are removed, and for [:alpha:] and [:alnum:] the underscore
144 character is removed. The triples in the table consist of the base map offset,
145 second map offset or -1 if no second map, and a non-negative value for map
146 addition or a negative value for map subtraction (if there are two maps). The
147 absolute value of the third field has these meanings: 0 => no tweaking, 1 =>
148 remove vertical space characters, 2 => remove underscore. */
149
150 static const int posix_class_maps[] = {
151 cbit_word, cbit_digit, -2, /* alpha */
152 cbit_lower, -1, 0, /* lower */
153 cbit_upper, -1, 0, /* upper */
154 cbit_word, -1, 2, /* alnum - word without underscore */
155 cbit_print, cbit_cntrl, 0, /* ascii */
156 cbit_space, -1, 1, /* blank - a GNU extension */
157 cbit_cntrl, -1, 0, /* cntrl */
158 cbit_digit, -1, 0, /* digit */
159 cbit_graph, -1, 0, /* graph */
160 cbit_print, -1, 0, /* print */
161 cbit_punct, -1, 0, /* punct */
162 cbit_space, -1, 0, /* space */
163 cbit_word, -1, 0, /* word - a Perl extension */
164 cbit_xdigit,-1, 0 /* xdigit */
165 };
166
167
168 #define STRING(a) # a
169 #define XSTRING(s) STRING(s)
170
171 /* The texts of compile-time error messages. These are "char *" because they
172 are passed to the outside world. Do not ever re-use any error number, because
173 they are documented. Always add a new error instead. Messages marked DEAD below
174 are no longer used. */
175
176 static const char *error_texts[] = {
177 "no error",
178 "\\ at end of pattern",
179 "\\c at end of pattern",
180 "unrecognized character follows \\",
181 "numbers out of order in {} quantifier",
182 /* 5 */
183 "number too big in {} quantifier",
184 "missing terminating ] for character class",
185 "invalid escape sequence in character class",
186 "range out of order in character class",
187 "nothing to repeat",
188 /* 10 */
189 "operand of unlimited repeat could match the empty string", /** DEAD **/
190 "internal error: unexpected repeat",
191 "unrecognized character after (?",
192 "POSIX named classes are supported only within a class",
193 "missing )",
194 /* 15 */
195 "reference to non-existent subpattern",
196 "erroffset passed as NULL",
197 "unknown option bit(s) set",
198 "missing ) after comment",
199 "parentheses nested too deeply", /** DEAD **/
200 /* 20 */
201 "regular expression too large",
202 "failed to get memory",
203 "unmatched parentheses",
204 "internal error: code overflow",
205 "unrecognized character after (?<",
206 /* 25 */
207 "lookbehind assertion is not fixed length",
208 "malformed number or name after (?(",
209 "conditional group contains more than two branches",
210 "assertion expected after (?(",
211 "(?R or (?[+-]digits must be followed by )",
212 /* 30 */
213 "unknown POSIX class name",
214 "POSIX collating elements are not supported",
215 "this version of PCRE is not compiled with PCRE_UTF8 support",
216 "spare error", /** DEAD **/
217 "character value in \\x{...} sequence is too large",
218 /* 35 */
219 "invalid condition (?(0)",
220 "\\C not allowed in lookbehind assertion",
221 "PCRE does not support \\L, \\l, \\N, \\U, or \\u",
222 "number after (?C is > 255",
223 "closing ) for (?C expected",
224 /* 40 */
225 "recursive call could loop indefinitely",
226 "unrecognized character after (?P",
227 "syntax error in subpattern name (missing terminator)",
228 "two named subpatterns have the same name",
229 "invalid UTF-8 string",
230 /* 45 */
231 "support for \\P, \\p, and \\X has not been compiled",
232 "malformed \\P or \\p sequence",
233 "unknown property name after \\P or \\p",
234 "subpattern name is too long (maximum " XSTRING(MAX_NAME_SIZE) " characters)",
235 "too many named subpatterns (maximum " XSTRING(MAX_NAME_COUNT) ")",
236 /* 50 */
237 "repeated subpattern is too long",
238 "octal value is greater than \\377 (not in UTF-8 mode)",
239 "internal error: overran compiling workspace",
240 "internal error: previously-checked referenced subpattern not found",
241 "DEFINE group contains more than one branch",
242 /* 55 */
243 "repeating a DEFINE group is not allowed",
244 "inconsistent NEWLINE options",
245 "\\g is not followed by an (optionally braced) non-zero number",
246 "(?+ or (?- or (?(+ or (?(- must be followed by a non-zero number"
247 };
248
249
250 /* Table to identify digits and hex digits. This is used when compiling
251 patterns. Note that the tables in chartables are dependent on the locale, and
252 may mark arbitrary characters as digits - but the PCRE compiling code expects
253 to handle only 0-9, a-z, and A-Z as digits when compiling. That is why we have
254 a private table here. It costs 256 bytes, but it is a lot faster than doing
255 character value tests (at least in some simple cases I timed), and in some
256 applications one wants PCRE to compile efficiently as well as match
257 efficiently.
258
259 For convenience, we use the same bit definitions as in chartables:
260
261 0x04 decimal digit
262 0x08 hexadecimal digit
263
264 Then we can use ctype_digit and ctype_xdigit in the code. */
265
266 #ifndef EBCDIC /* This is the "normal" case, for ASCII systems */
267 static const unsigned char digitab[] =
268 {
269 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 0- 7 */
270 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 8- 15 */
271 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 16- 23 */
272 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 24- 31 */
273 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* - ' */
274 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* ( - / */
275 0x0c,0x0c,0x0c,0x0c,0x0c,0x0c,0x0c,0x0c, /* 0 - 7 */
276 0x0c,0x0c,0x00,0x00,0x00,0x00,0x00,0x00, /* 8 - ? */
277 0x00,0x08,0x08,0x08,0x08,0x08,0x08,0x00, /* @ - G */
278 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* H - O */
279 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* P - W */
280 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* X - _ */
281 0x00,0x08,0x08,0x08,0x08,0x08,0x08,0x00, /* ` - g */
282 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* h - o */
283 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* p - w */
284 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* x -127 */
285 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 128-135 */
286 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 136-143 */
287 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 144-151 */
288 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 152-159 */
289 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 160-167 */
290 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 168-175 */
291 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 176-183 */
292 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 184-191 */
293 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 192-199 */
294 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 200-207 */
295 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 208-215 */
296 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 216-223 */
297 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 224-231 */
298 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 232-239 */
299 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 240-247 */
300 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00};/* 248-255 */
301
302 #else /* This is the "abnormal" case, for EBCDIC systems */
303 static const unsigned char digitab[] =
304 {
305 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 0- 7 0 */
306 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 8- 15 */
307 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 16- 23 10 */
308 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 24- 31 */
309 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 32- 39 20 */
310 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 40- 47 */
311 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 48- 55 30 */
312 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 56- 63 */
313 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* - 71 40 */
314 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 72- | */
315 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* & - 87 50 */
316 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 88- 95 */
317 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* - -103 60 */
318 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 104- ? */
319 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 112-119 70 */
320 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 120- " */
321 0x00,0x08,0x08,0x08,0x08,0x08,0x08,0x00, /* 128- g 80 */
322 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* h -143 */
323 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 144- p 90 */
324 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* q -159 */
325 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 160- x A0 */
326 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* y -175 */
327 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* ^ -183 B0 */
328 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 184-191 */
329 0x00,0x08,0x08,0x08,0x08,0x08,0x08,0x00, /* { - G C0 */
330 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* H -207 */
331 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* } - P D0 */
332 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* Q -223 */
333 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* \ - X E0 */
334 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* Y -239 */
335 0x0c,0x0c,0x0c,0x0c,0x0c,0x0c,0x0c,0x0c, /* 0 - 7 F0 */
336 0x0c,0x0c,0x00,0x00,0x00,0x00,0x00,0x00};/* 8 -255 */
337
338 static const unsigned char ebcdic_chartab[] = { /* chartable partial dup */
339 0x80,0x00,0x00,0x00,0x00,0x01,0x00,0x00, /* 0- 7 */
340 0x00,0x00,0x00,0x00,0x01,0x01,0x00,0x00, /* 8- 15 */
341 0x00,0x00,0x00,0x00,0x00,0x01,0x00,0x00, /* 16- 23 */
342 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 24- 31 */
343 0x00,0x00,0x00,0x00,0x00,0x01,0x00,0x00, /* 32- 39 */
344 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 40- 47 */
345 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 48- 55 */
346 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 56- 63 */
347 0x01,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* - 71 */
348 0x00,0x00,0x00,0x80,0x00,0x80,0x80,0x80, /* 72- | */
349 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* & - 87 */
350 0x00,0x00,0x00,0x80,0x80,0x80,0x00,0x00, /* 88- 95 */
351 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* - -103 */
352 0x00,0x00,0x00,0x00,0x00,0x10,0x00,0x80, /* 104- ? */
353 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 112-119 */
354 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 120- " */
355 0x00,0x1a,0x1a,0x1a,0x1a,0x1a,0x1a,0x12, /* 128- g */
356 0x12,0x12,0x00,0x00,0x00,0x00,0x00,0x00, /* h -143 */
357 0x00,0x12,0x12,0x12,0x12,0x12,0x12,0x12, /* 144- p */
358 0x12,0x12,0x00,0x00,0x00,0x00,0x00,0x00, /* q -159 */
359 0x00,0x00,0x12,0x12,0x12,0x12,0x12,0x12, /* 160- x */
360 0x12,0x12,0x00,0x00,0x00,0x00,0x00,0x00, /* y -175 */
361 0x80,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* ^ -183 */
362 0x00,0x00,0x80,0x00,0x00,0x00,0x00,0x00, /* 184-191 */
363 0x80,0x1a,0x1a,0x1a,0x1a,0x1a,0x1a,0x12, /* { - G */
364 0x12,0x12,0x00,0x00,0x00,0x00,0x00,0x00, /* H -207 */
365 0x00,0x12,0x12,0x12,0x12,0x12,0x12,0x12, /* } - P */
366 0x12,0x12,0x00,0x00,0x00,0x00,0x00,0x00, /* Q -223 */
367 0x00,0x00,0x12,0x12,0x12,0x12,0x12,0x12, /* \ - X */
368 0x12,0x12,0x00,0x00,0x00,0x00,0x00,0x00, /* Y -239 */
369 0x1c,0x1c,0x1c,0x1c,0x1c,0x1c,0x1c,0x1c, /* 0 - 7 */
370 0x1c,0x1c,0x00,0x00,0x00,0x00,0x00,0x00};/* 8 -255 */
371 #endif
372
373
374 /* Definition to allow mutual recursion */
375
376 static BOOL
377 compile_regex(int, int, uschar **, const uschar **, int *, BOOL, int, int *,
378 int *, branch_chain *, compile_data *, int *);
379
380
381
382 /*************************************************
383 * Handle escapes *
384 *************************************************/
385
386 /* This function is called when a \ has been encountered. It either returns a
387 positive value for a simple escape such as \n, or a negative value which
388 encodes one of the more complicated things such as \d. A backreference to group
389 n is returned as -(ESC_REF + n); ESC_REF is the highest ESC_xxx macro. When
390 UTF-8 is enabled, a positive value greater than 255 may be returned. On entry,
391 ptr is pointing at the \. On exit, it is on the final character of the escape
392 sequence.
393
394 Arguments:
395 ptrptr points to the pattern position pointer
396 errorcodeptr points to the errorcode variable
397 bracount number of previous extracting brackets
398 options the options bits
399 isclass TRUE if inside a character class
400
401 Returns: zero or positive => a data character
402 negative => a special escape sequence
403 on error, errorptr is set
404 */
405
406 static int
407 check_escape(const uschar **ptrptr, int *errorcodeptr, int bracount,
408 int options, BOOL isclass)
409 {
410 BOOL utf8 = (options & PCRE_UTF8) != 0;
411 const uschar *ptr = *ptrptr + 1;
412 int c, i;
413
414 GETCHARINCTEST(c, ptr); /* Get character value, increment pointer */
415 ptr--; /* Set pointer back to the last byte */
416
417 /* If backslash is at the end of the pattern, it's an error. */
418
419 if (c == 0) *errorcodeptr = ERR1;
420
421 /* Non-alphamerics are literals. For digits or letters, do an initial lookup in
422 a table. A non-zero result is something that can be returned immediately.
423 Otherwise further processing may be required. */
424
425 #ifndef EBCDIC /* ASCII coding */
426 else if (c < '0' || c > 'z') {} /* Not alphameric */
427 else if ((i = escapes[c - '0']) != 0) c = i;
428
429 #else /* EBCDIC coding */
430 else if (c < 'a' || (ebcdic_chartab[c] & 0x0E) == 0) {} /* Not alphameric */
431 else if ((i = escapes[c - 0x48]) != 0) c = i;
432 #endif
433
434 /* Escapes that need further processing, or are illegal. */
435
436 else
437 {
438 const uschar *oldptr;
439 BOOL braced, negated;
440
441 switch (c)
442 {
443 /* A number of Perl escapes are not handled by PCRE. We give an explicit
444 error. */
445
446 case 'l':
447 case 'L':
448 case 'N':
449 case 'u':
450 case 'U':
451 *errorcodeptr = ERR37;
452 break;
453
454 /* \g must be followed by a number, either plain or braced. If positive, it
455 is an absolute backreference. If negative, it is a relative backreference.
456 This is a Perl 5.10 feature. */
457
458 case 'g':
459 if (ptr[1] == '{')
460 {
461 braced = TRUE;
462 ptr++;
463 }
464 else braced = FALSE;
465
466 if (ptr[1] == '-')
467 {
468 negated = TRUE;
469 ptr++;
470 }
471 else negated = FALSE;
472
473 c = 0;
474 while ((digitab[ptr[1]] & ctype_digit) != 0)
475 c = c * 10 + *(++ptr) - '0';
476
477 if (c == 0 || (braced && *(++ptr) != '}'))
478 {
479 *errorcodeptr = ERR57;
480 return 0;
481 }
482
483 if (negated)
484 {
485 if (c > bracount)
486 {
487 *errorcodeptr = ERR15;
488 return 0;
489 }
490 c = bracount - (c - 1);
491 }
492
493 c = -(ESC_REF + c);
494 break;
495
496 /* The handling of escape sequences consisting of a string of digits
497 starting with one that is not zero is not straightforward. By experiment,
498 the way Perl works seems to be as follows:
499
500 Outside a character class, the digits are read as a decimal number. If the
501 number is less than 10, or if there are that many previous extracting
502 left brackets, then it is a back reference. Otherwise, up to three octal
503 digits are read to form an escaped byte. Thus \123 is likely to be octal
504 123 (cf \0123, which is octal 012 followed by the literal 3). If the octal
505 value is greater than 377, the least significant 8 bits are taken. Inside a
506 character class, \ followed by a digit is always an octal number. */
507
508 case '1': case '2': case '3': case '4': case '5':
509 case '6': case '7': case '8': case '9':
510
511 if (!isclass)
512 {
513 oldptr = ptr;
514 c -= '0';
515 while ((digitab[ptr[1]] & ctype_digit) != 0)
516 c = c * 10 + *(++ptr) - '0';
517 if (c < 10 || c <= bracount)
518 {
519 c = -(ESC_REF + c);
520 break;
521 }
522 ptr = oldptr; /* Put the pointer back and fall through */
523 }
524
525 /* Handle an octal number following \. If the first digit is 8 or 9, Perl
526 generates a binary zero byte and treats the digit as a following literal.
527 Thus we have to pull back the pointer by one. */
528
529 if ((c = *ptr) >= '8')
530 {
531 ptr--;
532 c = 0;
533 break;
534 }
535
536 /* \0 always starts an octal number, but we may drop through to here with a
537 larger first octal digit. The original code used just to take the least
538 significant 8 bits of octal numbers (I think this is what early Perls used
539 to do). Nowadays we allow for larger numbers in UTF-8 mode, but no more
540 than 3 octal digits. */
541
542 case '0':
543 c -= '0';
544 while(i++ < 2 && ptr[1] >= '0' && ptr[1] <= '7')
545 c = c * 8 + *(++ptr) - '0';
546 if (!utf8 && c > 255) *errorcodeptr = ERR51;
547 break;
548
549 /* \x is complicated. \x{ddd} is a character number which can be greater
550 than 0xff in utf8 mode, but only if the ddd are hex digits. If not, { is
551 treated as a data character. */
552
553 case 'x':
554 if (ptr[1] == '{')
555 {
556 const uschar *pt = ptr + 2;
557 int count = 0;
558
559 c = 0;
560 while ((digitab[*pt] & ctype_xdigit) != 0)
561 {
562 register int cc = *pt++;
563 if (c == 0 && cc == '0') continue; /* Leading zeroes */
564 count++;
565
566 #ifndef EBCDIC /* ASCII coding */
567 if (cc >= 'a') cc -= 32; /* Convert to upper case */
568 c = (c << 4) + cc - ((cc < 'A')? '0' : ('A' - 10));
569 #else /* EBCDIC coding */
570 if (cc >= 'a' && cc <= 'z') cc += 64; /* Convert to upper case */
571 c = (c << 4) + cc - ((cc >= '0')? '0' : ('A' - 10));
572 #endif
573 }
574
575 if (*pt == '}')
576 {
577 if (c < 0 || count > (utf8? 8 : 2)) *errorcodeptr = ERR34;
578 ptr = pt;
579 break;
580 }
581
582 /* If the sequence of hex digits does not end with '}', then we don't
583 recognize this construct; fall through to the normal \x handling. */
584 }
585
586 /* Read just a single-byte hex-defined char */
587
588 c = 0;
589 while (i++ < 2 && (digitab[ptr[1]] & ctype_xdigit) != 0)
590 {
591 int cc; /* Some compilers don't like ++ */
592 cc = *(++ptr); /* in initializers */
593 #ifndef EBCDIC /* ASCII coding */
594 if (cc >= 'a') cc -= 32; /* Convert to upper case */
595 c = c * 16 + cc - ((cc < 'A')? '0' : ('A' - 10));
596 #else /* EBCDIC coding */
597 if (cc <= 'z') cc += 64; /* Convert to upper case */
598 c = c * 16 + cc - ((cc >= '0')? '0' : ('A' - 10));
599 #endif
600 }
601 break;
602
603 /* For \c, a following letter is upper-cased; then the 0x40 bit is flipped.
604 This coding is ASCII-specific, but then the whole concept of \cx is
605 ASCII-specific. (However, an EBCDIC equivalent has now been added.) */
606
607 case 'c':
608 c = *(++ptr);
609 if (c == 0)
610 {
611 *errorcodeptr = ERR2;
612 return 0;
613 }
614
615 #ifndef EBCDIC /* ASCII coding */
616 if (c >= 'a' && c <= 'z') c -= 32;
617 c ^= 0x40;
618 #else /* EBCDIC coding */
619 if (c >= 'a' && c <= 'z') c += 64;
620 c ^= 0xC0;
621 #endif
622 break;
623
624 /* PCRE_EXTRA enables extensions to Perl in the matter of escapes. Any
625 other alphameric following \ is an error if PCRE_EXTRA was set; otherwise,
626 for Perl compatibility, it is a literal. This code looks a bit odd, but
627 there used to be some cases other than the default, and there may be again
628 in future, so I haven't "optimized" it. */
629
630 default:
631 if ((options & PCRE_EXTRA) != 0) switch(c)
632 {
633 default:
634 *errorcodeptr = ERR3;
635 break;
636 }
637 break;
638 }
639 }
640
641 *ptrptr = ptr;
642 return c;
643 }
644
645
646
647 #ifdef SUPPORT_UCP
648 /*************************************************
649 * Handle \P and \p *
650 *************************************************/
651
652 /* This function is called after \P or \p has been encountered, provided that
653 PCRE is compiled with support for Unicode properties. On entry, ptrptr is
654 pointing at the P or p. On exit, it is pointing at the final character of the
655 escape sequence.
656
657 Argument:
658 ptrptr points to the pattern position pointer
659 negptr points to a boolean that is set TRUE for negation else FALSE
660 dptr points to an int that is set to the detailed property value
661 errorcodeptr points to the error code variable
662
663 Returns: type value from ucp_type_table, or -1 for an invalid type
664 */
665
666 static int
667 get_ucp(const uschar **ptrptr, BOOL *negptr, int *dptr, int *errorcodeptr)
668 {
669 int c, i, bot, top;
670 const uschar *ptr = *ptrptr;
671 char name[32];
672
673 c = *(++ptr);
674 if (c == 0) goto ERROR_RETURN;
675
676 *negptr = FALSE;
677
678 /* \P or \p can be followed by a name in {}, optionally preceded by ^ for
679 negation. */
680
681 if (c == '{')
682 {
683 if (ptr[1] == '^')
684 {
685 *negptr = TRUE;
686 ptr++;
687 }
688 for (i = 0; i < sizeof(name) - 1; i++)
689 {
690 c = *(++ptr);
691 if (c == 0) goto ERROR_RETURN;
692 if (c == '}') break;
693 name[i] = c;
694 }
695 if (c !='}') goto ERROR_RETURN;
696 name[i] = 0;
697 }
698
699 /* Otherwise there is just one following character */
700
701 else
702 {
703 name[0] = c;
704 name[1] = 0;
705 }
706
707 *ptrptr = ptr;
708
709 /* Search for a recognized property name using binary chop */
710
711 bot = 0;
712 top = _pcre_utt_size;
713
714 while (bot < top)
715 {
716 i = (bot + top) >> 1;
717 c = strcmp(name, _pcre_utt[i].name);
718 if (c == 0)
719 {
720 *dptr = _pcre_utt[i].value;
721 return _pcre_utt[i].type;
722 }
723 if (c > 0) bot = i + 1; else top = i;
724 }
725
726 *errorcodeptr = ERR47;
727 *ptrptr = ptr;
728 return -1;
729
730 ERROR_RETURN:
731 *errorcodeptr = ERR46;
732 *ptrptr = ptr;
733 return -1;
734 }
735 #endif
736
737
738
739
740 /*************************************************
741 * Check for counted repeat *
742 *************************************************/
743
744 /* This function is called when a '{' is encountered in a place where it might
745 start a quantifier. It looks ahead to see if it really is a quantifier or not.
746 It is only a quantifier if it is one of the forms {ddd} {ddd,} or {ddd,ddd}
747 where the ddds are digits.
748
749 Arguments:
750 p pointer to the first char after '{'
751
752 Returns: TRUE or FALSE
753 */
754
755 static BOOL
756 is_counted_repeat(const uschar *p)
757 {
758 if ((digitab[*p++] & ctype_digit) == 0) return FALSE;
759 while ((digitab[*p] & ctype_digit) != 0) p++;
760 if (*p == '}') return TRUE;
761
762 if (*p++ != ',') return FALSE;
763 if (*p == '}') return TRUE;
764
765 if ((digitab[*p++] & ctype_digit) == 0) return FALSE;
766 while ((digitab[*p] & ctype_digit) != 0) p++;
767
768 return (*p == '}');
769 }
770
771
772
773 /*************************************************
774 * Read repeat counts *
775 *************************************************/
776
777 /* Read an item of the form {n,m} and return the values. This is called only
778 after is_counted_repeat() has confirmed that a repeat-count quantifier exists,
779 so the syntax is guaranteed to be correct, but we need to check the values.
780
781 Arguments:
782 p pointer to first char after '{'
783 minp pointer to int for min
784 maxp pointer to int for max
785 returned as -1 if no max
786 errorcodeptr points to error code variable
787
788 Returns: pointer to '}' on success;
789 current ptr on error, with errorcodeptr set non-zero
790 */
791
792 static const uschar *
793 read_repeat_counts(const uschar *p, int *minp, int *maxp, int *errorcodeptr)
794 {
795 int min = 0;
796 int max = -1;
797
798 /* Read the minimum value and do a paranoid check: a negative value indicates
799 an integer overflow. */
800
801 while ((digitab[*p] & ctype_digit) != 0) min = min * 10 + *p++ - '0';
802 if (min < 0 || min > 65535)
803 {
804 *errorcodeptr = ERR5;
805 return p;
806 }
807
808 /* Read the maximum value if there is one, and again do a paranoid on its size.
809 Also, max must not be less than min. */
810
811 if (*p == '}') max = min; else
812 {
813 if (*(++p) != '}')
814 {
815 max = 0;
816 while((digitab[*p] & ctype_digit) != 0) max = max * 10 + *p++ - '0';
817 if (max < 0 || max > 65535)
818 {
819 *errorcodeptr = ERR5;
820 return p;
821 }
822 if (max < min)
823 {
824 *errorcodeptr = ERR4;
825 return p;
826 }
827 }
828 }
829
830 /* Fill in the required variables, and pass back the pointer to the terminating
831 '}'. */
832
833 *minp = min;
834 *maxp = max;
835 return p;
836 }
837
838
839
840 /*************************************************
841 * Find forward referenced subpattern *
842 *************************************************/
843
844 /* This function scans along a pattern's text looking for capturing
845 subpatterns, and counting them. If it finds a named pattern that matches the
846 name it is given, it returns its number. Alternatively, if the name is NULL, it
847 returns when it reaches a given numbered subpattern. This is used for forward
848 references to subpatterns. We know that if (?P< is encountered, the name will
849 be terminated by '>' because that is checked in the first pass.
850
851 Arguments:
852 ptr current position in the pattern
853 count current count of capturing parens so far encountered
854 name name to seek, or NULL if seeking a numbered subpattern
855 lorn name length, or subpattern number if name is NULL
856 xmode TRUE if we are in /x mode
857
858 Returns: the number of the named subpattern, or -1 if not found
859 */
860
861 static int
862 find_parens(const uschar *ptr, int count, const uschar *name, int lorn,
863 BOOL xmode)
864 {
865 const uschar *thisname;
866
867 for (; *ptr != 0; ptr++)
868 {
869 int term;
870
871 /* Skip over backslashed characters and also entire \Q...\E */
872
873 if (*ptr == '\\')
874 {
875 if (*(++ptr) == 0) return -1;
876 if (*ptr == 'Q') for (;;)
877 {
878 while (*(++ptr) != 0 && *ptr != '\\');
879 if (*ptr == 0) return -1;
880 if (*(++ptr) == 'E') break;
881 }
882 continue;
883 }
884
885 /* Skip over character classes */
886
887 if (*ptr == '[')
888 {
889 while (*(++ptr) != ']')
890 {
891 if (*ptr == '\\')
892 {
893 if (*(++ptr) == 0) return -1;
894 if (*ptr == 'Q') for (;;)
895 {
896 while (*(++ptr) != 0 && *ptr != '\\');
897 if (*ptr == 0) return -1;
898 if (*(++ptr) == 'E') break;
899 }
900 continue;
901 }
902 }
903 continue;
904 }
905
906 /* Skip comments in /x mode */
907
908 if (xmode && *ptr == '#')
909 {
910 while (*(++ptr) != 0 && *ptr != '\n');
911 if (*ptr == 0) return -1;
912 continue;
913 }
914
915 /* An opening parens must now be a real metacharacter */
916
917 if (*ptr != '(') continue;
918 if (ptr[1] != '?')
919 {
920 count++;
921 if (name == NULL && count == lorn) return count;
922 continue;
923 }
924
925 ptr += 2;
926 if (*ptr == 'P') ptr++; /* Allow optional P */
927
928 /* We have to disambiguate (?<! and (?<= from (?<name> */
929
930 if ((*ptr != '<' || ptr[1] == '!' || ptr[1] == '=') &&
931 *ptr != '\'')
932 continue;
933
934 count++;
935
936 if (name == NULL && count == lorn) return count;
937 term = *ptr++;
938 if (term == '<') term = '>';
939 thisname = ptr;
940 while (*ptr != term) ptr++;
941 if (name != NULL && lorn == ptr - thisname &&
942 strncmp((const char *)name, (const char *)thisname, lorn) == 0)
943 return count;
944 }
945
946 return -1;
947 }
948
949
950
951 /*************************************************
952 * Find first significant op code *
953 *************************************************/
954
955 /* This is called by several functions that scan a compiled expression looking
956 for a fixed first character, or an anchoring op code etc. It skips over things
957 that do not influence this. For some calls, a change of option is important.
958 For some calls, it makes sense to skip negative forward and all backward
959 assertions, and also the \b assertion; for others it does not.
960
961 Arguments:
962 code pointer to the start of the group
963 options pointer to external options
964 optbit the option bit whose changing is significant, or
965 zero if none are
966 skipassert TRUE if certain assertions are to be skipped
967
968 Returns: pointer to the first significant opcode
969 */
970
971 static const uschar*
972 first_significant_code(const uschar *code, int *options, int optbit,
973 BOOL skipassert)
974 {
975 for (;;)
976 {
977 switch ((int)*code)
978 {
979 case OP_OPT:
980 if (optbit > 0 && ((int)code[1] & optbit) != (*options & optbit))
981 *options = (int)code[1];
982 code += 2;
983 break;
984
985 case OP_ASSERT_NOT:
986 case OP_ASSERTBACK:
987 case OP_ASSERTBACK_NOT:
988 if (!skipassert) return code;
989 do code += GET(code, 1); while (*code == OP_ALT);
990 code += _pcre_OP_lengths[*code];
991 break;
992
993 case OP_WORD_BOUNDARY:
994 case OP_NOT_WORD_BOUNDARY:
995 if (!skipassert) return code;
996 /* Fall through */
997
998 case OP_CALLOUT:
999 case OP_CREF:
1000 case OP_RREF:
1001 case OP_DEF:
1002 code += _pcre_OP_lengths[*code];
1003 break;
1004
1005 default:
1006 return code;
1007 }
1008 }
1009 /* Control never reaches here */
1010 }
1011
1012
1013
1014
1015 /*************************************************
1016 * Find the fixed length of a pattern *
1017 *************************************************/
1018
1019 /* Scan a pattern and compute the fixed length of subject that will match it,
1020 if the length is fixed. This is needed for dealing with backward assertions.
1021 In UTF8 mode, the result is in characters rather than bytes.
1022
1023 Arguments:
1024 code points to the start of the pattern (the bracket)
1025 options the compiling options
1026
1027 Returns: the fixed length, or -1 if there is no fixed length,
1028 or -2 if \C was encountered
1029 */
1030
1031 static int
1032 find_fixedlength(uschar *code, int options)
1033 {
1034 int length = -1;
1035
1036 register int branchlength = 0;
1037 register uschar *cc = code + 1 + LINK_SIZE;
1038
1039 /* Scan along the opcodes for this branch. If we get to the end of the
1040 branch, check the length against that of the other branches. */
1041
1042 for (;;)
1043 {
1044 int d;
1045 register int op = *cc;
1046
1047 switch (op)
1048 {
1049 case OP_CBRA:
1050 case OP_BRA:
1051 case OP_ONCE:
1052 case OP_COND:
1053 d = find_fixedlength(cc + ((op == OP_CBRA)? 2:0), options);
1054 if (d < 0) return d;
1055 branchlength += d;
1056 do cc += GET(cc, 1); while (*cc == OP_ALT);
1057 cc += 1 + LINK_SIZE;
1058 break;
1059
1060 /* Reached end of a branch; if it's a ket it is the end of a nested
1061 call. If it's ALT it is an alternation in a nested call. If it is
1062 END it's the end of the outer call. All can be handled by the same code. */
1063
1064 case OP_ALT:
1065 case OP_KET:
1066 case OP_KETRMAX:
1067 case OP_KETRMIN:
1068 case OP_END:
1069 if (length < 0) length = branchlength;
1070 else if (length != branchlength) return -1;
1071 if (*cc != OP_ALT) return length;
1072 cc += 1 + LINK_SIZE;
1073 branchlength = 0;
1074 break;
1075
1076 /* Skip over assertive subpatterns */
1077
1078 case OP_ASSERT:
1079 case OP_ASSERT_NOT:
1080 case OP_ASSERTBACK:
1081 case OP_ASSERTBACK_NOT:
1082 do cc += GET(cc, 1); while (*cc == OP_ALT);
1083 /* Fall through */
1084
1085 /* Skip over things that don't match chars */
1086
1087 case OP_REVERSE:
1088 case OP_CREF:
1089 case OP_RREF:
1090 case OP_DEF:
1091 case OP_OPT:
1092 case OP_CALLOUT:
1093 case OP_SOD:
1094 case OP_SOM:
1095 case OP_EOD:
1096 case OP_EODN:
1097 case OP_CIRC:
1098 case OP_DOLL:
1099 case OP_NOT_WORD_BOUNDARY:
1100 case OP_WORD_BOUNDARY:
1101 cc += _pcre_OP_lengths[*cc];
1102 break;
1103
1104 /* Handle literal characters */
1105
1106 case OP_CHAR:
1107 case OP_CHARNC:
1108 case OP_NOT:
1109 branchlength++;
1110 cc += 2;
1111 #ifdef SUPPORT_UTF8
1112 if ((options & PCRE_UTF8) != 0)
1113 {
1114 while ((*cc & 0xc0) == 0x80) cc++;
1115 }
1116 #endif
1117 break;
1118
1119 /* Handle exact repetitions. The count is already in characters, but we
1120 need to skip over a multibyte character in UTF8 mode. */
1121
1122 case OP_EXACT:
1123 branchlength += GET2(cc,1);
1124 cc += 4;
1125 #ifdef SUPPORT_UTF8
1126 if ((options & PCRE_UTF8) != 0)
1127 {
1128 while((*cc & 0x80) == 0x80) cc++;
1129 }
1130 #endif
1131 break;
1132
1133 case OP_TYPEEXACT:
1134 branchlength += GET2(cc,1);
1135 cc += 4;
1136 break;
1137
1138 /* Handle single-char matchers */
1139
1140 case OP_PROP:
1141 case OP_NOTPROP:
1142 cc += 2;
1143 /* Fall through */
1144
1145 case OP_NOT_DIGIT:
1146 case OP_DIGIT:
1147 case OP_NOT_WHITESPACE:
1148 case OP_WHITESPACE:
1149 case OP_NOT_WORDCHAR:
1150 case OP_WORDCHAR:
1151 case OP_ANY:
1152 branchlength++;
1153 cc++;
1154 break;
1155
1156 /* The single-byte matcher isn't allowed */
1157
1158 case OP_ANYBYTE:
1159 return -2;
1160
1161 /* Check a class for variable quantification */
1162
1163 #ifdef SUPPORT_UTF8
1164 case OP_XCLASS:
1165 cc += GET(cc, 1) - 33;
1166 /* Fall through */
1167 #endif
1168
1169 case OP_CLASS:
1170 case OP_NCLASS:
1171 cc += 33;
1172
1173 switch (*cc)
1174 {
1175 case OP_CRSTAR:
1176 case OP_CRMINSTAR:
1177 case OP_CRQUERY:
1178 case OP_CRMINQUERY:
1179 return -1;
1180
1181 case OP_CRRANGE:
1182 case OP_CRMINRANGE:
1183 if (GET2(cc,1) != GET2(cc,3)) return -1;
1184 branchlength += GET2(cc,1);
1185 cc += 5;
1186 break;
1187
1188 default:
1189 branchlength++;
1190 }
1191 break;
1192
1193 /* Anything else is variable length */
1194
1195 default:
1196 return -1;
1197 }
1198 }
1199 /* Control never gets here */
1200 }
1201
1202
1203
1204
1205 /*************************************************
1206 * Scan compiled regex for numbered bracket *
1207 *************************************************/
1208
1209 /* This little function scans through a compiled pattern until it finds a
1210 capturing bracket with the given number.
1211
1212 Arguments:
1213 code points to start of expression
1214 utf8 TRUE in UTF-8 mode
1215 number the required bracket number
1216
1217 Returns: pointer to the opcode for the bracket, or NULL if not found
1218 */
1219
1220 static const uschar *
1221 find_bracket(const uschar *code, BOOL utf8, int number)
1222 {
1223 for (;;)
1224 {
1225 register int c = *code;
1226 if (c == OP_END) return NULL;
1227
1228 /* XCLASS is used for classes that cannot be represented just by a bit
1229 map. This includes negated single high-valued characters. The length in
1230 the table is zero; the actual length is stored in the compiled code. */
1231
1232 if (c == OP_XCLASS) code += GET(code, 1);
1233
1234 /* Handle capturing bracket */
1235
1236 else if (c == OP_CBRA)
1237 {
1238 int n = GET2(code, 1+LINK_SIZE);
1239 if (n == number) return (uschar *)code;
1240 code += _pcre_OP_lengths[c];
1241 }
1242
1243 /* In UTF-8 mode, opcodes that are followed by a character may be followed by
1244 a multi-byte character. The length in the table is a minimum, so we have to
1245 arrange to skip the extra bytes. */
1246
1247 else
1248 {
1249 code += _pcre_OP_lengths[c];
1250 #ifdef SUPPORT_UTF8
1251 if (utf8) switch(c)
1252 {
1253 case OP_CHAR:
1254 case OP_CHARNC:
1255 case OP_EXACT:
1256 case OP_UPTO:
1257 case OP_MINUPTO:
1258 case OP_POSUPTO:
1259 case OP_STAR:
1260 case OP_MINSTAR:
1261 case OP_POSSTAR:
1262 case OP_PLUS:
1263 case OP_MINPLUS:
1264 case OP_POSPLUS:
1265 case OP_QUERY:
1266 case OP_MINQUERY:
1267 case OP_POSQUERY:
1268 if (code[-1] >= 0xc0) code += _pcre_utf8_table4[code[-1] & 0x3f];
1269 break;
1270 }
1271 #endif
1272 }
1273 }
1274 }
1275
1276
1277
1278 /*************************************************
1279 * Scan compiled regex for recursion reference *
1280 *************************************************/
1281
1282 /* This little function scans through a compiled pattern until it finds an
1283 instance of OP_RECURSE.
1284
1285 Arguments:
1286 code points to start of expression
1287 utf8 TRUE in UTF-8 mode
1288
1289 Returns: pointer to the opcode for OP_RECURSE, or NULL if not found
1290 */
1291
1292 static const uschar *
1293 find_recurse(const uschar *code, BOOL utf8)
1294 {
1295 for (;;)
1296 {
1297 register int c = *code;
1298 if (c == OP_END) return NULL;
1299 if (c == OP_RECURSE) return code;
1300
1301 /* XCLASS is used for classes that cannot be represented just by a bit
1302 map. This includes negated single high-valued characters. The length in
1303 the table is zero; the actual length is stored in the compiled code. */
1304
1305 if (c == OP_XCLASS) code += GET(code, 1);
1306
1307 /* Otherwise, we get the item's length from the table. In UTF-8 mode, opcodes
1308 that are followed by a character may be followed by a multi-byte character.
1309 The length in the table is a minimum, so we have to arrange to skip the extra
1310 bytes. */
1311
1312 else
1313 {
1314 code += _pcre_OP_lengths[c];
1315 #ifdef SUPPORT_UTF8
1316 if (utf8) switch(c)
1317 {
1318 case OP_CHAR:
1319 case OP_CHARNC:
1320 case OP_EXACT:
1321 case OP_UPTO:
1322 case OP_MINUPTO:
1323 case OP_POSUPTO:
1324 case OP_STAR:
1325 case OP_MINSTAR:
1326 case OP_POSSTAR:
1327 case OP_PLUS:
1328 case OP_MINPLUS:
1329 case OP_POSPLUS:
1330 case OP_QUERY:
1331 case OP_MINQUERY:
1332 case OP_POSQUERY:
1333 if (code[-1] >= 0xc0) code += _pcre_utf8_table4[code[-1] & 0x3f];
1334 break;
1335 }
1336 #endif
1337 }
1338 }
1339 }
1340
1341
1342
1343 /*************************************************
1344 * Scan compiled branch for non-emptiness *
1345 *************************************************/
1346
1347 /* This function scans through a branch of a compiled pattern to see whether it
1348 can match the empty string or not. It is called from could_be_empty()
1349 below and from compile_branch() when checking for an unlimited repeat of a
1350 group that can match nothing. Note that first_significant_code() skips over
1351 assertions. If we hit an unclosed bracket, we return "empty" - this means we've
1352 struck an inner bracket whose current branch will already have been scanned.
1353
1354 Arguments:
1355 code points to start of search
1356 endcode points to where to stop
1357 utf8 TRUE if in UTF8 mode
1358
1359 Returns: TRUE if what is matched could be empty
1360 */
1361
1362 static BOOL
1363 could_be_empty_branch(const uschar *code, const uschar *endcode, BOOL utf8)
1364 {
1365 register int c;
1366 for (code = first_significant_code(code + _pcre_OP_lengths[*code], NULL, 0, TRUE);
1367 code < endcode;
1368 code = first_significant_code(code + _pcre_OP_lengths[c], NULL, 0, TRUE))
1369 {
1370 const uschar *ccode;
1371
1372 c = *code;
1373
1374 /* Groups with zero repeats can of course be empty; skip them. */
1375
1376 if (c == OP_BRAZERO || c == OP_BRAMINZERO)
1377 {
1378 do code += GET(code, 1); while (*code == OP_ALT);
1379 c = *code;
1380 continue;
1381 }
1382
1383 /* For other groups, scan the branches. */
1384
1385 if (c == OP_BRA || c == OP_CBRA || c == OP_ONCE)
1386 {
1387 BOOL empty_branch;
1388 if (GET(code, 1) == 0) return TRUE; /* Hit unclosed bracket */
1389
1390 /* Scan a closed bracket */
1391
1392 empty_branch = FALSE;
1393 do
1394 {
1395 if (!empty_branch && could_be_empty_branch(code, endcode, utf8))
1396 empty_branch = TRUE;
1397 code += GET(code, 1);
1398 }
1399 while (*code == OP_ALT);
1400 if (!empty_branch) return FALSE; /* All branches are non-empty */
1401 c = *code;
1402 continue;
1403 }
1404
1405 /* Handle the other opcodes */
1406
1407 switch (c)
1408 {
1409 /* Check for quantifiers after a class */
1410
1411 #ifdef SUPPORT_UTF8
1412 case OP_XCLASS:
1413 ccode = code + GET(code, 1);
1414 goto CHECK_CLASS_REPEAT;
1415 #endif
1416
1417 case OP_CLASS:
1418 case OP_NCLASS:
1419 ccode = code + 33;
1420
1421 #ifdef SUPPORT_UTF8
1422 CHECK_CLASS_REPEAT:
1423 #endif
1424
1425 switch (*ccode)
1426 {
1427 case OP_CRSTAR: /* These could be empty; continue */
1428 case OP_CRMINSTAR:
1429 case OP_CRQUERY:
1430 case OP_CRMINQUERY:
1431 break;
1432
1433 default: /* Non-repeat => class must match */
1434 case OP_CRPLUS: /* These repeats aren't empty */
1435 case OP_CRMINPLUS:
1436 return FALSE;
1437
1438 case OP_CRRANGE:
1439 case OP_CRMINRANGE:
1440 if (GET2(ccode, 1) > 0) return FALSE; /* Minimum > 0 */
1441 break;
1442 }
1443 break;
1444
1445 /* Opcodes that must match a character */
1446
1447 case OP_PROP:
1448 case OP_NOTPROP:
1449 case OP_EXTUNI:
1450 case OP_NOT_DIGIT:
1451 case OP_DIGIT:
1452 case OP_NOT_WHITESPACE:
1453 case OP_WHITESPACE:
1454 case OP_NOT_WORDCHAR:
1455 case OP_WORDCHAR:
1456 case OP_ANY:
1457 case OP_ANYBYTE:
1458 case OP_CHAR:
1459 case OP_CHARNC:
1460 case OP_NOT:
1461 case OP_PLUS:
1462 case OP_MINPLUS:
1463 case OP_POSPLUS:
1464 case OP_EXACT:
1465 case OP_NOTPLUS:
1466 case OP_NOTMINPLUS:
1467 case OP_NOTPOSPLUS:
1468 case OP_NOTEXACT:
1469 case OP_TYPEPLUS:
1470 case OP_TYPEMINPLUS:
1471 case OP_TYPEPOSPLUS:
1472 case OP_TYPEEXACT:
1473 return FALSE;
1474
1475 /* End of branch */
1476
1477 case OP_KET:
1478 case OP_KETRMAX:
1479 case OP_KETRMIN:
1480 case OP_ALT:
1481 return TRUE;
1482
1483 /* In UTF-8 mode, STAR, MINSTAR, POSSTAR, QUERY, MINQUERY, POSQUERY, UPTO,
1484 MINUPTO, and POSUPTO may be followed by a multibyte character */
1485
1486 #ifdef SUPPORT_UTF8
1487 case OP_STAR:
1488 case OP_MINSTAR:
1489 case OP_POSSTAR:
1490 case OP_QUERY:
1491 case OP_MINQUERY:
1492 case OP_POSQUERY:
1493 case OP_UPTO:
1494 case OP_MINUPTO:
1495 case OP_POSUPTO:
1496 if (utf8) while ((code[2] & 0xc0) == 0x80) code++;
1497 break;
1498 #endif
1499 }
1500 }
1501
1502 return TRUE;
1503 }
1504
1505
1506
1507 /*************************************************
1508 * Scan compiled regex for non-emptiness *
1509 *************************************************/
1510
1511 /* This function is called to check for left recursive calls. We want to check
1512 the current branch of the current pattern to see if it could match the empty
1513 string. If it could, we must look outwards for branches at other levels,
1514 stopping when we pass beyond the bracket which is the subject of the recursion.
1515
1516 Arguments:
1517 code points to start of the recursion
1518 endcode points to where to stop (current RECURSE item)
1519 bcptr points to the chain of current (unclosed) branch starts
1520 utf8 TRUE if in UTF-8 mode
1521
1522 Returns: TRUE if what is matched could be empty
1523 */
1524
1525 static BOOL
1526 could_be_empty(const uschar *code, const uschar *endcode, branch_chain *bcptr,
1527 BOOL utf8)
1528 {
1529 while (bcptr != NULL && bcptr->current >= code)
1530 {
1531 if (!could_be_empty_branch(bcptr->current, endcode, utf8)) return FALSE;
1532 bcptr = bcptr->outer;
1533 }
1534 return TRUE;
1535 }
1536
1537
1538
1539 /*************************************************
1540 * Check for POSIX class syntax *
1541 *************************************************/
1542
1543 /* This function is called when the sequence "[:" or "[." or "[=" is
1544 encountered in a character class. It checks whether this is followed by an
1545 optional ^ and then a sequence of letters, terminated by a matching ":]" or
1546 ".]" or "=]".
1547
1548 Argument:
1549 ptr pointer to the initial [
1550 endptr where to return the end pointer
1551 cd pointer to compile data
1552
1553 Returns: TRUE or FALSE
1554 */
1555
1556 static BOOL
1557 check_posix_syntax(const uschar *ptr, const uschar **endptr, compile_data *cd)
1558 {
1559 int terminator; /* Don't combine these lines; the Solaris cc */
1560 terminator = *(++ptr); /* compiler warns about "non-constant" initializer. */
1561 if (*(++ptr) == '^') ptr++;
1562 while ((cd->ctypes[*ptr] & ctype_letter) != 0) ptr++;
1563 if (*ptr == terminator && ptr[1] == ']')
1564 {
1565 *endptr = ptr;
1566 return TRUE;
1567 }
1568 return FALSE;
1569 }
1570
1571
1572
1573
1574 /*************************************************
1575 * Check POSIX class name *
1576 *************************************************/
1577
1578 /* This function is called to check the name given in a POSIX-style class entry
1579 such as [:alnum:].
1580
1581 Arguments:
1582 ptr points to the first letter
1583 len the length of the name
1584
1585 Returns: a value representing the name, or -1 if unknown
1586 */
1587
1588 static int
1589 check_posix_name(const uschar *ptr, int len)
1590 {
1591 register int yield = 0;
1592 while (posix_name_lengths[yield] != 0)
1593 {
1594 if (len == posix_name_lengths[yield] &&
1595 strncmp((const char *)ptr, posix_names[yield], len) == 0) return yield;
1596 yield++;
1597 }
1598 return -1;
1599 }
1600
1601
1602 /*************************************************
1603 * Adjust OP_RECURSE items in repeated group *
1604 *************************************************/
1605
1606 /* OP_RECURSE items contain an offset from the start of the regex to the group
1607 that is referenced. This means that groups can be replicated for fixed
1608 repetition simply by copying (because the recursion is allowed to refer to
1609 earlier groups that are outside the current group). However, when a group is
1610 optional (i.e. the minimum quantifier is zero), OP_BRAZERO is inserted before
1611 it, after it has been compiled. This means that any OP_RECURSE items within it
1612 that refer to the group itself or any contained groups have to have their
1613 offsets adjusted. That one of the jobs of this function. Before it is called,
1614 the partially compiled regex must be temporarily terminated with OP_END.
1615
1616 This function has been extended with the possibility of forward references for
1617 recursions and subroutine calls. It must also check the list of such references
1618 for the group we are dealing with. If it finds that one of the recursions in
1619 the current group is on this list, it adjusts the offset in the list, not the
1620 value in the reference (which is a group number).
1621
1622 Arguments:
1623 group points to the start of the group
1624 adjust the amount by which the group is to be moved
1625 utf8 TRUE in UTF-8 mode
1626 cd contains pointers to tables etc.
1627 save_hwm the hwm forward reference pointer at the start of the group
1628
1629 Returns: nothing
1630 */
1631
1632 static void
1633 adjust_recurse(uschar *group, int adjust, BOOL utf8, compile_data *cd,
1634 uschar *save_hwm)
1635 {
1636 uschar *ptr = group;
1637 while ((ptr = (uschar *)find_recurse(ptr, utf8)) != NULL)
1638 {
1639 int offset;
1640 uschar *hc;
1641
1642 /* See if this recursion is on the forward reference list. If so, adjust the
1643 reference. */
1644
1645 for (hc = save_hwm; hc < cd->hwm; hc += LINK_SIZE)
1646 {
1647 offset = GET(hc, 0);
1648 if (cd->start_code + offset == ptr + 1)
1649 {
1650 PUT(hc, 0, offset + adjust);
1651 break;
1652 }
1653 }
1654
1655 /* Otherwise, adjust the recursion offset if it's after the start of this
1656 group. */
1657
1658 if (hc >= cd->hwm)
1659 {
1660 offset = GET(ptr, 1);
1661 if (cd->start_code + offset >= group) PUT(ptr, 1, offset + adjust);
1662 }
1663
1664 ptr += 1 + LINK_SIZE;
1665 }
1666 }
1667
1668
1669
1670 /*************************************************
1671 * Insert an automatic callout point *
1672 *************************************************/
1673
1674 /* This function is called when the PCRE_AUTO_CALLOUT option is set, to insert
1675 callout points before each pattern item.
1676
1677 Arguments:
1678 code current code pointer
1679 ptr current pattern pointer
1680 cd pointers to tables etc
1681
1682 Returns: new code pointer
1683 */
1684
1685 static uschar *
1686 auto_callout(uschar *code, const uschar *ptr, compile_data *cd)
1687 {
1688 *code++ = OP_CALLOUT;
1689 *code++ = 255;
1690 PUT(code, 0, ptr - cd->start_pattern); /* Pattern offset */
1691 PUT(code, LINK_SIZE, 0); /* Default length */
1692 return code + 2*LINK_SIZE;
1693 }
1694
1695
1696
1697 /*************************************************
1698 * Complete a callout item *
1699 *************************************************/
1700
1701 /* A callout item contains the length of the next item in the pattern, which
1702 we can't fill in till after we have reached the relevant point. This is used
1703 for both automatic and manual callouts.
1704
1705 Arguments:
1706 previous_callout points to previous callout item
1707 ptr current pattern pointer
1708 cd pointers to tables etc
1709
1710 Returns: nothing
1711 */
1712
1713 static void
1714 complete_callout(uschar *previous_callout, const uschar *ptr, compile_data *cd)
1715 {
1716 int length = ptr - cd->start_pattern - GET(previous_callout, 2);
1717 PUT(previous_callout, 2 + LINK_SIZE, length);
1718 }
1719
1720
1721
1722 #ifdef SUPPORT_UCP
1723 /*************************************************
1724 * Get othercase range *
1725 *************************************************/
1726
1727 /* This function is passed the start and end of a class range, in UTF-8 mode
1728 with UCP support. It searches up the characters, looking for internal ranges of
1729 characters in the "other" case. Each call returns the next one, updating the
1730 start address.
1731
1732 Arguments:
1733 cptr points to starting character value; updated
1734 d end value
1735 ocptr where to put start of othercase range
1736 odptr where to put end of othercase range
1737
1738 Yield: TRUE when range returned; FALSE when no more
1739 */
1740
1741 static BOOL
1742 get_othercase_range(unsigned int *cptr, unsigned int d, unsigned int *ocptr,
1743 unsigned int *odptr)
1744 {
1745 unsigned int c, othercase, next;
1746
1747 for (c = *cptr; c <= d; c++)
1748 { if ((othercase = _pcre_ucp_othercase(c)) != NOTACHAR) break; }
1749
1750 if (c > d) return FALSE;
1751
1752 *ocptr = othercase;
1753 next = othercase + 1;
1754
1755 for (++c; c <= d; c++)
1756 {
1757 if (_pcre_ucp_othercase(c) != next) break;
1758 next++;
1759 }
1760
1761 *odptr = next - 1;
1762 *cptr = c;
1763
1764 return TRUE;
1765 }
1766 #endif /* SUPPORT_UCP */
1767
1768
1769
1770 /*************************************************
1771 * Check if auto-possessifying is possible *
1772 *************************************************/
1773
1774 /* This function is called for unlimited repeats of certain items, to see
1775 whether the next thing could possibly match the repeated item. If not, it makes
1776 sense to automatically possessify the repeated item.
1777
1778 Arguments:
1779 op_code the repeated op code
1780 this data for this item, depends on the opcode
1781 utf8 TRUE in UTF-8 mode
1782 utf8_char used for utf8 character bytes, NULL if not relevant
1783 ptr next character in pattern
1784 options options bits
1785 cd contains pointers to tables etc.
1786
1787 Returns: TRUE if possessifying is wanted
1788 */
1789
1790 static BOOL
1791 check_auto_possessive(int op_code, int item, BOOL utf8, uschar *utf8_char,
1792 const uschar *ptr, int options, compile_data *cd)
1793 {
1794 int next;
1795
1796 /* Skip whitespace and comments in extended mode */
1797
1798 if ((options & PCRE_EXTENDED) != 0)
1799 {
1800 for (;;)
1801 {
1802 while ((cd->ctypes[*ptr] & ctype_space) != 0) ptr++;
1803 if (*ptr == '#')
1804 {
1805 while (*(++ptr) != 0)
1806 if (IS_NEWLINE(ptr)) { ptr += cd->nllen; break; }
1807 }
1808 else break;
1809 }
1810 }
1811
1812 /* If the next item is one that we can handle, get its value. A non-negative
1813 value is a character, a negative value is an escape value. */
1814
1815 if (*ptr == '\\')
1816 {
1817 int temperrorcode = 0;
1818 next = check_escape(&ptr, &temperrorcode, cd->bracount, options, FALSE);
1819 if (temperrorcode != 0) return FALSE;
1820 ptr++; /* Point after the escape sequence */
1821 }
1822
1823 else if ((cd->ctypes[*ptr] & ctype_meta) == 0)
1824 {
1825 #ifdef SUPPORT_UTF8
1826 if (utf8) { GETCHARINC(next, ptr); } else
1827 #endif
1828 next = *ptr++;
1829 }
1830
1831 else return FALSE;
1832
1833 /* Skip whitespace and comments in extended mode */
1834
1835 if ((options & PCRE_EXTENDED) != 0)
1836 {
1837 for (;;)
1838 {
1839 while ((cd->ctypes[*ptr] & ctype_space) != 0) ptr++;
1840 if (*ptr == '#')
1841 {
1842 while (*(++ptr) != 0)
1843 if (IS_NEWLINE(ptr)) { ptr += cd->nllen; break; }
1844 }
1845 else break;
1846 }
1847 }
1848
1849 /* If the next thing is itself optional, we have to give up. */
1850
1851 if (*ptr == '*' || *ptr == '?' || strncmp((char *)ptr, "{0,", 3) == 0)
1852 return FALSE;
1853
1854 /* Now compare the next item with the previous opcode. If the previous is a
1855 positive single character match, "item" either contains the character or, if
1856 "item" is greater than 127 in utf8 mode, the character's bytes are in
1857 utf8_char. */
1858
1859
1860 /* Handle cases when the next item is a character. */
1861
1862 if (next >= 0) switch(op_code)
1863 {
1864 case OP_CHAR:
1865 #ifdef SUPPORT_UTF8
1866 if (utf8 && item > 127) { GETCHAR(item, utf8_char); }
1867 #endif
1868 return item != next;
1869
1870 /* For CHARNC (caseless character) we must check the other case. If we have
1871 Unicode property support, we can use it to test the other case of
1872 high-valued characters. */
1873
1874 case OP_CHARNC:
1875 #ifdef SUPPORT_UTF8
1876 if (utf8 && item > 127) { GETCHAR(item, utf8_char); }
1877 #endif
1878 if (item == next) return FALSE;
1879 #ifdef SUPPORT_UTF8
1880 if (utf8)
1881 {
1882 unsigned int othercase;
1883 if (next < 128) othercase = cd->fcc[next]; else
1884 #ifdef SUPPORT_UCP
1885 othercase = _pcre_ucp_othercase((unsigned int)next);
1886 #else
1887 othercase = NOTACHAR;
1888 #endif
1889 return (unsigned int)item != othercase;
1890 }
1891 else
1892 #endif /* SUPPORT_UTF8 */
1893 return (item != cd->fcc[next]); /* Non-UTF-8 mode */
1894
1895 /* For OP_NOT, "item" must be a single-byte character. */
1896
1897 case OP_NOT:
1898 if (next < 0) return FALSE; /* Not a character */
1899 if (item == next) return TRUE;
1900 if ((options & PCRE_CASELESS) == 0) return FALSE;
1901 #ifdef SUPPORT_UTF8
1902 if (utf8)
1903 {
1904 unsigned int othercase;
1905 if (next < 128) othercase = cd->fcc[next]; else
1906 #ifdef SUPPORT_UCP
1907 othercase = _pcre_ucp_othercase(next);
1908 #else
1909 othercase = NOTACHAR;
1910 #endif
1911 return (unsigned int)item == othercase;
1912 }
1913 else
1914 #endif /* SUPPORT_UTF8 */
1915 return (item == cd->fcc[next]); /* Non-UTF-8 mode */
1916
1917 case OP_DIGIT:
1918 return next > 127 || (cd->ctypes[next] & ctype_digit) == 0;
1919
1920 case OP_NOT_DIGIT:
1921 return next <= 127 && (cd->ctypes[next] & ctype_digit) != 0;
1922
1923 case OP_WHITESPACE:
1924 return next > 127 || (cd->ctypes[next] & ctype_space) == 0;
1925
1926 case OP_NOT_WHITESPACE:
1927 return next <= 127 && (cd->ctypes[next] & ctype_space) != 0;
1928
1929 case OP_WORDCHAR:
1930 return next > 127 || (cd->ctypes[next] & ctype_word) == 0;
1931
1932 case OP_NOT_WORDCHAR:
1933 return next <= 127 && (cd->ctypes[next] & ctype_word) != 0;
1934
1935 default:
1936 return FALSE;
1937 }
1938
1939
1940 /* Handle the case when the next item is \d, \s, etc. */
1941
1942 switch(op_code)
1943 {
1944 case OP_CHAR:
1945 case OP_CHARNC:
1946 #ifdef SUPPORT_UTF8
1947 if (utf8 && item > 127) { GETCHAR(item, utf8_char); }
1948 #endif
1949 switch(-next)
1950 {
1951 case ESC_d:
1952 return item > 127 || (cd->ctypes[item] & ctype_digit) == 0;
1953
1954 case ESC_D:
1955 return item <= 127 && (cd->ctypes[item] & ctype_digit) != 0;
1956
1957 case ESC_s:
1958 return item > 127 || (cd->ctypes[item] & ctype_space) == 0;
1959
1960 case ESC_S:
1961 return item <= 127 && (cd->ctypes[item] & ctype_space) != 0;
1962
1963 case ESC_w:
1964 return item > 127 || (cd->ctypes[item] & ctype_word) == 0;
1965
1966 case ESC_W:
1967 return item <= 127 && (cd->ctypes[item] & ctype_word) != 0;
1968
1969 default:
1970 return FALSE;
1971 }
1972
1973 case OP_DIGIT:
1974 return next == -ESC_D || next == -ESC_s || next == -ESC_W;
1975
1976 case OP_NOT_DIGIT:
1977 return next == -ESC_d;
1978
1979 case OP_WHITESPACE:
1980 return next == -ESC_S || next == -ESC_d || next == -ESC_w;
1981
1982 case OP_NOT_WHITESPACE:
1983 return next == -ESC_s;
1984
1985 case OP_WORDCHAR:
1986 return next == -ESC_W || next == -ESC_s;
1987
1988 case OP_NOT_WORDCHAR:
1989 return next == -ESC_w || next == -ESC_d;
1990
1991 default:
1992 return FALSE;
1993 }
1994
1995 /* Control does not reach here */
1996 }
1997
1998
1999
2000 /*************************************************
2001 * Compile one branch *
2002 *************************************************/
2003
2004 /* Scan the pattern, compiling it into the a vector. If the options are
2005 changed during the branch, the pointer is used to change the external options
2006 bits. This function is used during the pre-compile phase when we are trying
2007 to find out the amount of memory needed, as well as during the real compile
2008 phase. The value of lengthptr distinguishes the two phases.
2009
2010 Arguments:
2011 optionsptr pointer to the option bits
2012 codeptr points to the pointer to the current code point
2013 ptrptr points to the current pattern pointer
2014 errorcodeptr points to error code variable
2015 firstbyteptr set to initial literal character, or < 0 (REQ_UNSET, REQ_NONE)
2016 reqbyteptr set to the last literal character required, else < 0
2017 bcptr points to current branch chain
2018 cd contains pointers to tables etc.
2019 lengthptr NULL during the real compile phase
2020 points to length accumulator during pre-compile phase
2021
2022 Returns: TRUE on success
2023 FALSE, with *errorcodeptr set non-zero on error
2024 */
2025
2026 static BOOL
2027 compile_branch(int *optionsptr, uschar **codeptr, const uschar **ptrptr,
2028 int *errorcodeptr, int *firstbyteptr, int *reqbyteptr, branch_chain *bcptr,
2029 compile_data *cd, int *lengthptr)
2030 {
2031 int repeat_type, op_type;
2032 int repeat_min = 0, repeat_max = 0; /* To please picky compilers */
2033 int bravalue = 0;
2034 int greedy_default, greedy_non_default;
2035 int firstbyte, reqbyte;
2036 int zeroreqbyte, zerofirstbyte;
2037 int req_caseopt, reqvary, tempreqvary;
2038 int options = *optionsptr;
2039 int after_manual_callout = 0;
2040 int length_prevgroup = 0;
2041 register int c;
2042 register uschar *code = *codeptr;
2043 uschar *last_code = code;
2044 uschar *orig_code = code;
2045 uschar *tempcode;
2046 BOOL inescq = FALSE;
2047 BOOL groupsetfirstbyte = FALSE;
2048 const uschar *ptr = *ptrptr;
2049 const uschar *tempptr;
2050 uschar *previous = NULL;
2051 uschar *previous_callout = NULL;
2052 uschar *save_hwm = NULL;
2053 uschar classbits[32];
2054
2055 #ifdef SUPPORT_UTF8
2056 BOOL class_utf8;
2057 BOOL utf8 = (options & PCRE_UTF8) != 0;
2058 uschar *class_utf8data;
2059 uschar utf8_char[6];
2060 #else
2061 BOOL utf8 = FALSE;
2062 uschar *utf8_char = NULL;
2063 #endif
2064
2065 #ifdef DEBUG
2066 if (lengthptr != NULL) DPRINTF((">> start branch\n"));
2067 #endif
2068
2069 /* Set up the default and non-default settings for greediness */
2070
2071 greedy_default = ((options & PCRE_UNGREEDY) != 0);
2072 greedy_non_default = greedy_default ^ 1;
2073
2074 /* Initialize no first byte, no required byte. REQ_UNSET means "no char
2075 matching encountered yet". It gets changed to REQ_NONE if we hit something that
2076 matches a non-fixed char first char; reqbyte just remains unset if we never
2077 find one.
2078
2079 When we hit a repeat whose minimum is zero, we may have to adjust these values
2080 to take the zero repeat into account. This is implemented by setting them to
2081 zerofirstbyte and zeroreqbyte when such a repeat is encountered. The individual
2082 item types that can be repeated set these backoff variables appropriately. */
2083
2084 firstbyte = reqbyte = zerofirstbyte = zeroreqbyte = REQ_UNSET;
2085
2086 /* The variable req_caseopt contains either the REQ_CASELESS value or zero,
2087 according to the current setting of the caseless flag. REQ_CASELESS is a bit
2088 value > 255. It is added into the firstbyte or reqbyte variables to record the
2089 case status of the value. This is used only for ASCII characters. */
2090
2091 req_caseopt = ((options & PCRE_CASELESS) != 0)? REQ_CASELESS : 0;
2092
2093 /* Switch on next character until the end of the branch */
2094
2095 for (;; ptr++)
2096 {
2097 BOOL negate_class;
2098 BOOL possessive_quantifier;
2099 BOOL is_quantifier;
2100 BOOL is_recurse;
2101 int class_charcount;
2102 int class_lastchar;
2103 int newoptions;
2104 int recno;
2105 int refsign;
2106 int skipbytes;
2107 int subreqbyte;
2108 int subfirstbyte;
2109 int terminator;
2110 int mclength;
2111 uschar mcbuffer[8];
2112
2113 /* Get next byte in the pattern */
2114
2115 c = *ptr;
2116
2117 /* If we are in the pre-compile phase, accumulate the length used for the
2118 previous cycle of this loop. */
2119
2120 if (lengthptr != NULL)
2121 {
2122 #ifdef DEBUG
2123 if (code > cd->hwm) cd->hwm = code; /* High water info */
2124 #endif
2125 if (code > cd->start_workspace + COMPILE_WORK_SIZE) /* Check for overrun */
2126 {
2127 *errorcodeptr = ERR52;
2128 goto FAILED;
2129 }
2130
2131 /* There is at least one situation where code goes backwards: this is the
2132 case of a zero quantifier after a class (e.g. [ab]{0}). At compile time,
2133 the class is simply eliminated. However, it is created first, so we have to
2134 allow memory for it. Therefore, don't ever reduce the length at this point.
2135 */
2136
2137 if (code < last_code) code = last_code;
2138 *lengthptr += code - last_code;
2139 DPRINTF(("length=%d added %d c=%c\n", *lengthptr, code - last_code, c));
2140
2141 /* If "previous" is set and it is not at the start of the work space, move
2142 it back to there, in order to avoid filling up the work space. Otherwise,
2143 if "previous" is NULL, reset the current code pointer to the start. */
2144
2145 if (previous != NULL)
2146 {
2147 if (previous > orig_code)
2148 {
2149 memmove(orig_code, previous, code - previous);
2150 code -= previous - orig_code;
2151 previous = orig_code;
2152 }
2153 }
2154 else code = orig_code;
2155
2156 /* Remember where this code item starts so we can pick up the length
2157 next time round. */
2158
2159 last_code = code;
2160 }
2161
2162 /* In the real compile phase, just check the workspace used by the forward
2163 reference list. */
2164
2165 else if (cd->hwm > cd->start_workspace + COMPILE_WORK_SIZE)
2166 {
2167 *errorcodeptr = ERR52;
2168 goto FAILED;
2169 }
2170
2171 /* If in \Q...\E, check for the end; if not, we have a literal */
2172
2173 if (inescq && c != 0)
2174 {
2175 if (c == '\\' && ptr[1] == 'E')
2176 {
2177 inescq = FALSE;
2178 ptr++;
2179 continue;
2180 }
2181 else
2182 {
2183 if (previous_callout != NULL)
2184 {
2185 if (lengthptr == NULL) /* Don't attempt in pre-compile phase */
2186 complete_callout(previous_callout, ptr, cd);
2187 previous_callout = NULL;
2188 }
2189 if ((options & PCRE_AUTO_CALLOUT) != 0)
2190 {
2191 previous_callout = code;
2192 code = auto_callout(code, ptr, cd);
2193 }
2194 goto NORMAL_CHAR;
2195 }
2196 }
2197
2198 /* Fill in length of a previous callout, except when the next thing is
2199 a quantifier. */
2200
2201 is_quantifier = c == '*' || c == '+' || c == '?' ||
2202 (c == '{' && is_counted_repeat(ptr+1));
2203
2204 if (!is_quantifier && previous_callout != NULL &&
2205 after_manual_callout-- <= 0)
2206 {
2207 if (lengthptr == NULL) /* Don't attempt in pre-compile phase */
2208 complete_callout(previous_callout, ptr, cd);
2209 previous_callout = NULL;
2210 }
2211
2212 /* In extended mode, skip white space and comments */
2213
2214 if ((options & PCRE_EXTENDED) != 0)
2215 {
2216 if ((cd->ctypes[c] & ctype_space) != 0) continue;
2217 if (c == '#')
2218 {
2219 while (*(++ptr) != 0)
2220 {
2221 if (IS_NEWLINE(ptr)) { ptr += cd->nllen - 1; break; }
2222 }
2223 if (*ptr != 0) continue;
2224
2225 /* Else fall through to handle end of string */
2226 c = 0;
2227 }
2228 }
2229
2230 /* No auto callout for quantifiers. */
2231
2232 if ((options & PCRE_AUTO_CALLOUT) != 0 && !is_quantifier)
2233 {
2234 previous_callout = code;
2235 code = auto_callout(code, ptr, cd);
2236 }
2237
2238 switch(c)
2239 {
2240 /* ===================================================================*/
2241 case 0: /* The branch terminates at string end */
2242 case '|': /* or | or ) */
2243 case ')':
2244 *firstbyteptr = firstbyte;
2245 *reqbyteptr = reqbyte;
2246 *codeptr = code;
2247 *ptrptr = ptr;
2248 if (lengthptr != NULL)
2249 {
2250 *lengthptr += code - last_code; /* To include callout length */
2251 DPRINTF((">> end branch\n"));
2252 }
2253 return TRUE;
2254
2255
2256 /* ===================================================================*/
2257 /* Handle single-character metacharacters. In multiline mode, ^ disables
2258 the setting of any following char as a first character. */
2259
2260 case '^':
2261 if ((options & PCRE_MULTILINE) != 0)
2262 {
2263 if (firstbyte == REQ_UNSET) firstbyte = REQ_NONE;
2264 }
2265 previous = NULL;
2266 *code++ = OP_CIRC;
2267 break;
2268
2269 case '$':
2270 previous = NULL;
2271 *code++ = OP_DOLL;
2272 break;
2273
2274 /* There can never be a first char if '.' is first, whatever happens about
2275 repeats. The value of reqbyte doesn't change either. */
2276
2277 case '.':
2278 if (firstbyte == REQ_UNSET) firstbyte = REQ_NONE;
2279 zerofirstbyte = firstbyte;
2280 zeroreqbyte = reqbyte;
2281 previous = code;
2282 *code++ = OP_ANY;
2283 break;
2284
2285
2286 /* ===================================================================*/
2287 /* Character classes. If the included characters are all < 256, we build a
2288 32-byte bitmap of the permitted characters, except in the special case
2289 where there is only one such character. For negated classes, we build the
2290 map as usual, then invert it at the end. However, we use a different opcode
2291 so that data characters > 255 can be handled correctly.
2292
2293 If the class contains characters outside the 0-255 range, a different
2294 opcode is compiled. It may optionally have a bit map for characters < 256,
2295 but those above are are explicitly listed afterwards. A flag byte tells
2296 whether the bitmap is present, and whether this is a negated class or not.
2297 */
2298
2299 case '[':
2300 previous = code;
2301
2302 /* PCRE supports POSIX class stuff inside a class. Perl gives an error if
2303 they are encountered at the top level, so we'll do that too. */
2304
2305 if ((ptr[1] == ':' || ptr[1] == '.' || ptr[1] == '=') &&
2306 check_posix_syntax(ptr, &tempptr, cd))
2307 {
2308 *errorcodeptr = (ptr[1] == ':')? ERR13 : ERR31;
2309 goto FAILED;
2310 }
2311
2312 /* If the first character is '^', set the negation flag and skip it. */
2313
2314 if ((c = *(++ptr)) == '^')
2315 {
2316 negate_class = TRUE;
2317 c = *(++ptr);
2318 }
2319 else
2320 {
2321 negate_class = FALSE;
2322 }
2323
2324 /* Keep a count of chars with values < 256 so that we can optimize the case
2325 of just a single character (as long as it's < 256). However, For higher
2326 valued UTF-8 characters, we don't yet do any optimization. */
2327
2328 class_charcount = 0;
2329 class_lastchar = -1;
2330
2331 /* Initialize the 32-char bit map to all zeros. We build the map in a
2332 temporary bit of memory, in case the class contains only 1 character (less
2333 than 256), because in that case the compiled code doesn't use the bit map.
2334 */
2335
2336 memset(classbits, 0, 32 * sizeof(uschar));
2337
2338 #ifdef SUPPORT_UTF8
2339 class_utf8 = FALSE; /* No chars >= 256 */
2340 class_utf8data = code + LINK_SIZE + 2; /* For UTF-8 items */
2341 #endif
2342
2343 /* Process characters until ] is reached. By writing this as a "do" it
2344 means that an initial ] is taken as a data character. At the start of the
2345 loop, c contains the first byte of the character. */
2346
2347 if (c != 0) do
2348 {
2349 const uschar *oldptr;
2350
2351 #ifdef SUPPORT_UTF8
2352 if (utf8 && c > 127)
2353 { /* Braces are required because the */
2354 GETCHARLEN(c, ptr, ptr); /* macro generates multiple statements */
2355 }
2356 #endif
2357
2358 /* Inside \Q...\E everything is literal except \E */
2359
2360 if (inescq)
2361 {
2362 if (c == '\\' && ptr[1] == 'E') /* If we are at \E */
2363 {
2364 inescq = FALSE; /* Reset literal state */
2365 ptr++; /* Skip the 'E' */
2366 continue; /* Carry on with next */
2367 }
2368 goto CHECK_RANGE; /* Could be range if \E follows */
2369 }
2370
2371 /* Handle POSIX class names. Perl allows a negation extension of the
2372 form [:^name:]. A square bracket that doesn't match the syntax is
2373 treated as a literal. We also recognize the POSIX constructions
2374 [.ch.] and [=ch=] ("collating elements") and fault them, as Perl
2375 5.6 and 5.8 do. */
2376
2377 if (c == '[' &&
2378 (ptr[1] == ':' || ptr[1] == '.' || ptr[1] == '=') &&
2379 check_posix_syntax(ptr, &tempptr, cd))
2380 {
2381 BOOL local_negate = FALSE;
2382 int posix_class, taboffset, tabopt;
2383 register const uschar *cbits = cd->cbits;
2384 uschar pbits[32];
2385
2386 if (ptr[1] != ':')
2387 {
2388 *errorcodeptr = ERR31;
2389 goto FAILED;
2390 }
2391
2392 ptr += 2;
2393 if (*ptr == '^')
2394 {
2395 local_negate = TRUE;
2396 ptr++;
2397 }
2398
2399 posix_class = check_posix_name(ptr, tempptr - ptr);
2400 if (posix_class < 0)
2401 {
2402 *errorcodeptr = ERR30;
2403 goto FAILED;
2404 }
2405
2406 /* If matching is caseless, upper and lower are converted to
2407 alpha. This relies on the fact that the class table starts with
2408 alpha, lower, upper as the first 3 entries. */
2409
2410 if ((options & PCRE_CASELESS) != 0 && posix_class <= 2)
2411 posix_class = 0;
2412
2413 /* We build the bit map for the POSIX class in a chunk of local store
2414 because we may be adding and subtracting from it, and we don't want to
2415 subtract bits that may be in the main map already. At the end we or the
2416 result into the bit map that is being built. */
2417
2418 posix_class *= 3;
2419
2420 /* Copy in the first table (always present) */
2421
2422 memcpy(pbits, cbits + posix_class_maps[posix_class],
2423 32 * sizeof(uschar));
2424
2425 /* If there is a second table, add or remove it as required. */
2426
2427 taboffset = posix_class_maps[posix_class + 1];
2428 tabopt = posix_class_maps[posix_class + 2];
2429
2430 if (taboffset >= 0)
2431 {
2432 if (tabopt >= 0)
2433 for (c = 0; c < 32; c++) pbits[c] |= cbits[c + taboffset];
2434 else
2435 for (c = 0; c < 32; c++) pbits[c] &= ~cbits[c + taboffset];
2436 }
2437
2438 /* Not see if we need to remove any special characters. An option
2439 value of 1 removes vertical space and 2 removes underscore. */
2440
2441 if (tabopt < 0) tabopt = -tabopt;
2442 if (tabopt == 1) pbits[1] &= ~0x3c;
2443 else if (tabopt == 2) pbits[11] &= 0x7f;
2444
2445 /* Add the POSIX table or its complement into the main table that is
2446 being built and we are done. */
2447
2448 if (local_negate)
2449 for (c = 0; c < 32; c++) classbits[c] |= ~pbits[c];
2450 else
2451 for (c = 0; c < 32; c++) classbits[c] |= pbits[c];
2452
2453 ptr = tempptr + 1;
2454 class_charcount = 10; /* Set > 1; assumes more than 1 per class */
2455 continue; /* End of POSIX syntax handling */
2456 }
2457
2458 /* Backslash may introduce a single character, or it may introduce one
2459 of the specials, which just set a flag. The sequence \b is a special
2460 case. Inside a class (and only there) it is treated as backspace.
2461 Elsewhere it marks a word boundary. Other escapes have preset maps ready
2462 to or into the one we are building. We assume they have more than one
2463 character in them, so set class_charcount bigger than one. */
2464
2465 if (c == '\\')
2466 {
2467 c = check_escape(&ptr, errorcodeptr, cd->bracount, options, TRUE);
2468 if (*errorcodeptr != 0) goto FAILED;
2469
2470 if (-c == ESC_b) c = '\b'; /* \b is backslash in a class */
2471 else if (-c == ESC_X) c = 'X'; /* \X is literal X in a class */
2472 else if (-c == ESC_R) c = 'R'; /* \R is literal R in a class */
2473 else if (-c == ESC_Q) /* Handle start of quoted string */
2474 {
2475 if (ptr[1] == '\\' && ptr[2] == 'E')
2476 {
2477 ptr += 2; /* avoid empty string */
2478 }
2479 else inescq = TRUE;
2480 continue;
2481 }
2482
2483 if (c < 0)
2484 {
2485 register const uschar *cbits = cd->cbits;
2486 class_charcount += 2; /* Greater than 1 is what matters */
2487
2488 /* Save time by not doing this in the pre-compile phase. */
2489
2490 if (lengthptr == NULL) switch (-c)
2491 {
2492 case ESC_d:
2493 for (c = 0; c < 32; c++) classbits[c] |= cbits[c+cbit_digit];
2494 continue;
2495
2496 case ESC_D:
2497 for (c = 0; c < 32; c++) classbits[c] |= ~cbits[c+cbit_digit];
2498 continue;
2499
2500 case ESC_w:
2501 for (c = 0; c < 32; c++) classbits[c] |= cbits[c+cbit_word];
2502 continue;
2503
2504 case ESC_W:
2505 for (c = 0; c < 32; c++) classbits[c] |= ~cbits[c+cbit_word];
2506 continue;
2507
2508 case ESC_s:
2509 for (c = 0; c < 32; c++) classbits[c] |= cbits[c+cbit_space];
2510 classbits[1] &= ~0x08; /* Perl 5.004 onwards omits VT from \s */
2511 continue;
2512
2513 case ESC_S:
2514 for (c = 0; c < 32; c++) classbits[c] |= ~cbits[c+cbit_space];
2515 classbits[1] |= 0x08; /* Perl 5.004 onwards omits VT from \s */
2516 continue;
2517
2518 case ESC_E: /* Perl ignores an orphan \E */
2519 continue;
2520
2521 default: /* Not recognized; fall through */
2522 break; /* Need "default" setting to stop compiler warning. */
2523 }
2524
2525 /* In the pre-compile phase, just do the recognition. */
2526
2527 else if (c == -ESC_d || c == -ESC_D || c == -ESC_w ||
2528 c == -ESC_W || c == -ESC_s || c == -ESC_S) continue;
2529
2530 /* We need to deal with \P and \p in both phases. */
2531
2532 #ifdef SUPPORT_UCP
2533 if (-c == ESC_p || -c == ESC_P)
2534 {
2535 BOOL negated;
2536 int pdata;
2537 int ptype = get_ucp(&ptr, &negated, &pdata, errorcodeptr);
2538 if (ptype < 0) goto FAILED;
2539 class_utf8 = TRUE;
2540 *class_utf8data++ = ((-c == ESC_p) != negated)?
2541 XCL_PROP : XCL_NOTPROP;
2542 *class_utf8data++ = ptype;
2543 *class_utf8data++ = pdata;
2544 class_charcount -= 2; /* Not a < 256 character */
2545 continue;
2546 }
2547 #endif
2548 /* Unrecognized escapes are faulted if PCRE is running in its
2549 strict mode. By default, for compatibility with Perl, they are
2550 treated as literals. */
2551
2552 if ((options & PCRE_EXTRA) != 0)
2553 {
2554 *errorcodeptr = ERR7;
2555 goto FAILED;
2556 }
2557
2558 class_charcount -= 2; /* Undo the default count from above */
2559 c = *ptr; /* Get the final character and fall through */
2560 }
2561
2562 /* Fall through if we have a single character (c >= 0). This may be
2563 greater than 256 in UTF-8 mode. */
2564
2565 } /* End of backslash handling */
2566
2567 /* A single character may be followed by '-' to form a range. However,
2568 Perl does not permit ']' to be the end of the range. A '-' character
2569 at the end is treated as a literal. Perl ignores orphaned \E sequences
2570 entirely. The code for handling \Q and \E is messy. */
2571
2572 CHECK_RANGE:
2573 while (ptr[1] == '\\' && ptr[2] == 'E')
2574 {
2575 inescq = FALSE;
2576 ptr += 2;
2577 }
2578
2579 oldptr = ptr;
2580
2581 if (!inescq && ptr[1] == '-')
2582 {
2583 int d;
2584 ptr += 2;
2585 while (*ptr == '\\' && ptr[1] == 'E') ptr += 2;
2586
2587 /* If we hit \Q (not followed by \E) at this point, go into escaped
2588 mode. */
2589
2590 while (*ptr == '\\' && ptr[1] == 'Q')
2591 {
2592 ptr += 2;
2593 if (*ptr == '\\' && ptr[1] == 'E') { ptr += 2; continue; }
2594 inescq = TRUE;
2595 break;
2596 }
2597
2598 if (*ptr == 0 || (!inescq && *ptr == ']'))
2599 {
2600 ptr = oldptr;
2601 goto LONE_SINGLE_CHARACTER;
2602 }
2603
2604 #ifdef SUPPORT_UTF8
2605 if (utf8)
2606 { /* Braces are required because the */
2607 GETCHARLEN(d, ptr, ptr); /* macro generates multiple statements */
2608 }
2609 else
2610 #endif
2611 d = *ptr; /* Not UTF-8 mode */
2612
2613 /* The second part of a range can be a single-character escape, but
2614 not any of the other escapes. Perl 5.6 treats a hyphen as a literal
2615 in such circumstances. */
2616
2617 if (!inescq && d == '\\')
2618 {
2619 d = check_escape(&ptr, errorcodeptr, cd->bracount, options, TRUE);
2620 if (*errorcodeptr != 0) goto FAILED;
2621
2622 /* \b is backslash; \X is literal X; \R is literal R; any other
2623 special means the '-' was literal */
2624
2625 if (d < 0)
2626 {
2627 if (d == -ESC_b) d = '\b';
2628 else if (d == -ESC_X) d = 'X';
2629 else if (d == -ESC_R) d = 'R'; else
2630 {
2631 ptr = oldptr;
2632 goto LONE_SINGLE_CHARACTER; /* A few lines below */
2633 }
2634 }
2635 }
2636
2637 /* Check that the two values are in the correct order. Optimize
2638 one-character ranges */
2639
2640 if (d < c)
2641 {
2642 *errorcodeptr = ERR8;
2643 goto FAILED;
2644 }
2645
2646 if (d == c) goto LONE_SINGLE_CHARACTER; /* A few lines below */
2647
2648 /* In UTF-8 mode, if the upper limit is > 255, or > 127 for caseless
2649 matching, we have to use an XCLASS with extra data items. Caseless
2650 matching for characters > 127 is available only if UCP support is
2651 available. */
2652
2653 #ifdef SUPPORT_UTF8
2654 if (utf8 && (d > 255 || ((options & PCRE_CASELESS) != 0 && d > 127)))
2655 {
2656 class_utf8 = TRUE;
2657
2658 /* With UCP support, we can find the other case equivalents of
2659 the relevant characters. There may be several ranges. Optimize how
2660 they fit with the basic range. */
2661
2662 #ifdef SUPPORT_UCP
2663 if ((options & PCRE_CASELESS) != 0)
2664 {
2665 unsigned int occ, ocd;
2666 unsigned int cc = c;
2667 unsigned int origd = d;
2668 while (get_othercase_range(&cc, origd, &occ, &ocd))
2669 {
2670 if (occ >= c && ocd <= d) continue; /* Skip embedded ranges */
2671
2672 if (occ < c && ocd >= c - 1) /* Extend the basic range */
2673 { /* if there is overlap, */
2674 c = occ; /* noting that if occ < c */
2675 continue; /* we can't have ocd > d */
2676 } /* because a subrange is */
2677 if (ocd > d && occ <= d + 1) /* always shorter than */
2678 { /* the basic range. */
2679 d = ocd;
2680 continue;
2681 }
2682
2683 if (occ == ocd)
2684 {
2685 *class_utf8data++ = XCL_SINGLE;
2686 }
2687 else
2688 {
2689 *class_utf8data++ = XCL_RANGE;
2690 class_utf8data += _pcre_ord2utf8(occ, class_utf8data);
2691 }
2692 class_utf8data += _pcre_ord2utf8(ocd, class_utf8data);
2693 }
2694 }
2695 #endif /* SUPPORT_UCP */
2696
2697 /* Now record the original range, possibly modified for UCP caseless
2698 overlapping ranges. */
2699
2700 *class_utf8data++ = XCL_RANGE;
2701 class_utf8data += _pcre_ord2utf8(c, class_utf8data);
2702 class_utf8data += _pcre_ord2utf8(d, class_utf8data);
2703
2704 /* With UCP support, we are done. Without UCP support, there is no
2705 caseless matching for UTF-8 characters > 127; we can use the bit map
2706 for the smaller ones. */
2707
2708 #ifdef SUPPORT_UCP
2709 continue; /* With next character in the class */
2710 #else
2711 if ((options & PCRE_CASELESS) == 0 || c > 127) continue;
2712
2713 /* Adjust upper limit and fall through to set up the map */
2714
2715 d = 127;
2716
2717 #endif /* SUPPORT_UCP */
2718 }
2719 #endif /* SUPPORT_UTF8 */
2720
2721 /* We use the bit map for all cases when not in UTF-8 mode; else
2722 ranges that lie entirely within 0-127 when there is UCP support; else
2723 for partial ranges without UCP support. */
2724
2725 class_charcount += d - c + 1;
2726 class_lastchar = d;
2727
2728 /* We can save a bit of time by skipping this in the pre-compile. */
2729
2730 if (lengthptr == NULL) for (; c <= d; c++)
2731 {
2732 classbits[c/8] |= (1 << (c&7));
2733 if ((options & PCRE_CASELESS) != 0)
2734 {
2735 int uc = cd->fcc[c]; /* flip case */
2736 classbits[uc/8] |= (1 << (uc&7));
2737 }
2738 }
2739
2740 continue; /* Go get the next char in the class */
2741 }
2742
2743 /* Handle a lone single character - we can get here for a normal
2744 non-escape char, or after \ that introduces a single character or for an
2745 apparent range that isn't. */
2746
2747 LONE_SINGLE_CHARACTER:
2748
2749 /* Handle a character that cannot go in the bit map */
2750
2751 #ifdef SUPPORT_UTF8
2752 if (utf8 && (c > 255 || ((options & PCRE_CASELESS) != 0 && c > 127)))
2753 {
2754 class_utf8 = TRUE;
2755 *class_utf8data++ = XCL_SINGLE;
2756 class_utf8data += _pcre_ord2utf8(c, class_utf8data);
2757
2758 #ifdef SUPPORT_UCP
2759 if ((options & PCRE_CASELESS) != 0)
2760 {
2761 unsigned int othercase;
2762 if ((othercase = _pcre_ucp_othercase(c)) != NOTACHAR)
2763 {
2764 *class_utf8data++ = XCL_SINGLE;
2765 class_utf8data += _pcre_ord2utf8(othercase, class_utf8data);
2766 }
2767 }
2768 #endif /* SUPPORT_UCP */
2769
2770 }
2771 else
2772 #endif /* SUPPORT_UTF8 */
2773
2774 /* Handle a single-byte character */
2775 {
2776 classbits[c/8] |= (1 << (c&7));
2777 if ((options & PCRE_CASELESS) != 0)
2778 {
2779 c = cd->fcc[c]; /* flip case */
2780 classbits[c/8] |= (1 << (c&7));
2781 }
2782 class_charcount++;
2783 class_lastchar = c;
2784 }
2785 }
2786
2787 /* Loop until ']' reached. This "while" is the end of the "do" above. */
2788
2789 while ((c = *(++ptr)) != 0 && (c != ']' || inescq));
2790
2791 if (c == 0) /* Missing terminating ']' */
2792 {
2793 *errorcodeptr = ERR6;
2794 goto FAILED;
2795 }
2796
2797 /* If class_charcount is 1, we saw precisely one character whose value is
2798 less than 256. In non-UTF-8 mode we can always optimize. In UTF-8 mode, we
2799 can optimize the negative case only if there were no characters >= 128
2800 because OP_NOT and the related opcodes like OP_NOTSTAR operate on
2801 single-bytes only. This is an historical hangover. Maybe one day we can
2802 tidy these opcodes to handle multi-byte characters.
2803
2804 The optimization throws away the bit map. We turn the item into a
2805 1-character OP_CHAR[NC] if it's positive, or OP_NOT if it's negative. Note
2806 that OP_NOT does not support multibyte characters. In the positive case, it
2807 can cause firstbyte to be set. Otherwise, there can be no first char if
2808 this item is first, whatever repeat count may follow. In the case of
2809 reqbyte, save the previous value for reinstating. */
2810
2811 #ifdef SUPPORT_UTF8
2812 if (class_charcount == 1 &&
2813 (!utf8 ||
2814 (!class_utf8 && (!negate_class || class_lastchar < 128))))
2815
2816 #else
2817 if (class_charcount == 1)
2818 #endif
2819 {
2820 zeroreqbyte = reqbyte;
2821
2822 /* The OP_NOT opcode works on one-byte characters only. */
2823
2824 if (negate_class)
2825 {
2826 if (firstbyte == REQ_UNSET) firstbyte = REQ_NONE;
2827 zerofirstbyte = firstbyte;
2828 *code++ = OP_NOT;
2829 *code++ = class_lastchar;
2830 break;
2831 }
2832
2833 /* For a single, positive character, get the value into mcbuffer, and
2834 then we can handle this with the normal one-character code. */
2835
2836 #ifdef SUPPORT_UTF8
2837 if (utf8 && class_lastchar > 127)
2838 mclength = _pcre_ord2utf8(class_lastchar, mcbuffer);
2839 else
2840 #endif
2841 {
2842 mcbuffer[0] = class_lastchar;
2843 mclength = 1;
2844 }
2845 goto ONE_CHAR;
2846 } /* End of 1-char optimization */
2847
2848 /* The general case - not the one-char optimization. If this is the first
2849 thing in the branch, there can be no first char setting, whatever the
2850 repeat count. Any reqbyte setting must remain unchanged after any kind of
2851 repeat. */
2852
2853 if (firstbyte == REQ_UNSET) firstbyte = REQ_NONE;
2854 zerofirstbyte = firstbyte;
2855 zeroreqbyte = reqbyte;
2856
2857 /* If there are characters with values > 255, we have to compile an
2858 extended class, with its own opcode. If there are no characters < 256,
2859 we can omit the bitmap in the actual compiled code. */
2860
2861 #ifdef SUPPORT_UTF8
2862 if (class_utf8)
2863 {
2864 *class_utf8data++ = XCL_END; /* Marks the end of extra data */
2865 *code++ = OP_XCLASS;
2866 code += LINK_SIZE;
2867 *code = negate_class? XCL_NOT : 0;
2868
2869 /* If the map is required, move up the extra data to make room for it;
2870 otherwise just move the code pointer to the end of the extra data. */
2871
2872 if (class_charcount > 0)
2873 {
2874 *code++ |= XCL_MAP;
2875 memmove(code + 32, code, class_utf8data - code);
2876 memcpy(code, classbits, 32);
2877 code = class_utf8data + 32;
2878 }
2879 else code = class_utf8data;
2880
2881 /* Now fill in the complete length of the item */
2882
2883 PUT(previous, 1, code - previous);
2884 break; /* End of class handling */
2885 }
2886 #endif
2887
2888 /* If there are no characters > 255, negate the 32-byte map if necessary,
2889 and copy it into the code vector. If this is the first thing in the branch,
2890 there can be no first char setting, whatever the repeat count. Any reqbyte
2891 setting must remain unchanged after any kind of repeat. */
2892
2893 if (negate_class)
2894 {
2895 *code++ = OP_NCLASS;
2896 if (lengthptr == NULL) /* Save time in the pre-compile phase */
2897 for (c = 0; c < 32; c++) code[c] = ~classbits[c];
2898 }
2899 else
2900 {
2901 *code++ = OP_CLASS;
2902 memcpy(code, classbits, 32);
2903 }
2904 code += 32;
2905 break;
2906
2907
2908 /* ===================================================================*/
2909 /* Various kinds of repeat; '{' is not necessarily a quantifier, but this
2910 has been tested above. */
2911
2912 case '{':
2913 if (!is_quantifier) goto NORMAL_CHAR;
2914 ptr = read_repeat_counts(ptr+1, &repeat_min, &repeat_max, errorcodeptr);
2915 if (*errorcodeptr != 0) goto FAILED;
2916 goto REPEAT;
2917
2918 case '*':
2919 repeat_min = 0;
2920 repeat_max = -1;
2921 goto REPEAT;
2922
2923 case '+':
2924 repeat_min = 1;
2925 repeat_max = -1;
2926 goto REPEAT;
2927
2928 case '?':
2929 repeat_min = 0;
2930 repeat_max = 1;
2931
2932 REPEAT:
2933 if (previous == NULL)
2934 {
2935 *errorcodeptr = ERR9;
2936 goto FAILED;
2937 }
2938
2939 if (repeat_min == 0)
2940 {
2941 firstbyte = zerofirstbyte; /* Adjust for zero repeat */
2942 reqbyte = zeroreqbyte; /* Ditto */
2943 }
2944
2945 /* Remember whether this is a variable length repeat */
2946
2947 reqvary = (repeat_min == repeat_max)? 0 : REQ_VARY;
2948
2949 op_type = 0; /* Default single-char op codes */
2950 possessive_quantifier = FALSE; /* Default not possessive quantifier */
2951
2952 /* Save start of previous item, in case we have to move it up to make space
2953 for an inserted OP_ONCE for the additional '+' extension. */
2954
2955 tempcode = previous;
2956
2957 /* If the next character is '+', we have a possessive quantifier. This
2958 implies greediness, whatever the setting of the PCRE_UNGREEDY option.
2959 If the next character is '?' this is a minimizing repeat, by default,
2960 but if PCRE_UNGREEDY is set, it works the other way round. We change the
2961 repeat type to the non-default. */
2962
2963 if (ptr[1] == '+')
2964 {
2965 repeat_type = 0; /* Force greedy */
2966 possessive_quantifier = TRUE;
2967 ptr++;
2968 }
2969 else if (ptr[1] == '?')
2970 {
2971 repeat_type = greedy_non_default;
2972 ptr++;
2973 }
2974 else repeat_type = greedy_default;
2975
2976 /* If previous was a character match, abolish the item and generate a
2977 repeat item instead. If a char item has a minumum of more than one, ensure
2978 that it is set in reqbyte - it might not be if a sequence such as x{3} is
2979 the first thing in a branch because the x will have gone into firstbyte
2980 instead. */
2981
2982 if (*previous == OP_CHAR || *previous == OP_CHARNC)
2983 {
2984 /* Deal with UTF-8 characters that take up more than one byte. It's
2985 easier to write this out separately than try to macrify it. Use c to
2986 hold the length of the character in bytes, plus 0x80 to flag that it's a
2987 length rather than a small character. */
2988
2989 #ifdef SUPPORT_UTF8
2990 if (utf8 && (code[-1] & 0x80) != 0)
2991 {
2992 uschar *lastchar = code - 1;
2993 while((*lastchar & 0xc0) == 0x80) lastchar--;
2994 c = code - lastchar; /* Length of UTF-8 character */
2995 memcpy(utf8_char, lastchar, c); /* Save the char */
2996 c |= 0x80; /* Flag c as a length */
2997 }
2998 else
2999 #endif
3000
3001 /* Handle the case of a single byte - either with no UTF8 support, or
3002 with UTF-8 disabled, or for a UTF-8 character < 128. */
3003
3004 {
3005 c = code[-1];
3006 if (repeat_min > 1) reqbyte = c | req_caseopt | cd->req_varyopt;
3007 }
3008
3009 /* If the repetition is unlimited, it pays to see if the next thing on
3010 the line is something that cannot possibly match this character. If so,
3011 automatically possessifying this item gains some performance in the case
3012 where the match fails. */
3013
3014 if (!possessive_quantifier &&
3015 repeat_max < 0 &&
3016 check_auto_possessive(*previous, c, utf8, utf8_char, ptr + 1,
3017 options, cd))
3018 {
3019 repeat_type = 0; /* Force greedy */
3020 possessive_quantifier = TRUE;
3021 }
3022
3023 goto OUTPUT_SINGLE_REPEAT; /* Code shared with single character types */
3024 }
3025
3026 /* If previous was a single negated character ([^a] or similar), we use
3027 one of the special opcodes, replacing it. The code is shared with single-
3028 character repeats by setting opt_type to add a suitable offset into
3029 repeat_type. We can also test for auto-possessification. OP_NOT is
3030 currently used only for single-byte chars. */
3031
3032 else if (*previous == OP_NOT)
3033 {
3034 op_type = OP_NOTSTAR - OP_STAR; /* Use "not" opcodes */
3035 c = previous[1];
3036 if (!possessive_quantifier &&
3037 repeat_max < 0 &&
3038 check_auto_possessive(OP_NOT, c, utf8, NULL, ptr + 1, options, cd))
3039 {
3040 repeat_type = 0; /* Force greedy */
3041 possessive_quantifier = TRUE;
3042 }
3043 goto OUTPUT_SINGLE_REPEAT;
3044 }
3045
3046 /* If previous was a character type match (\d or similar), abolish it and
3047 create a suitable repeat item. The code is shared with single-character
3048 repeats by setting op_type to add a suitable offset into repeat_type. Note
3049 the the Unicode property types will be present only when SUPPORT_UCP is
3050 defined, but we don't wrap the little bits of code here because it just
3051 makes it horribly messy. */
3052
3053 else if (*previous < OP_EODN)
3054 {
3055 uschar *oldcode;
3056 int prop_type, prop_value;
3057 op_type = OP_TYPESTAR - OP_STAR; /* Use type opcodes */
3058 c = *previous;
3059
3060 if (!possessive_quantifier &&
3061 repeat_max < 0 &&
3062 check_auto_possessive(c, 0, utf8, NULL, ptr + 1, options, cd))
3063 {
3064 repeat_type = 0; /* Force greedy */
3065 possessive_quantifier = TRUE;
3066 }
3067
3068 OUTPUT_SINGLE_REPEAT:
3069 if (*previous == OP_PROP || *previous == OP_NOTPROP)
3070 {
3071 prop_type = previous[1];
3072 prop_value = previous[2];
3073 }
3074 else prop_type = prop_value = -1;
3075
3076 oldcode = code;
3077 code = previous; /* Usually overwrite previous item */
3078
3079 /* If the maximum is zero then the minimum must also be zero; Perl allows
3080 this case, so we do too - by simply omitting the item altogether. */
3081
3082 if (repeat_max == 0) goto END_REPEAT;
3083
3084 /* All real repeats make it impossible to handle partial matching (maybe
3085 one day we will be able to remove this restriction). */
3086
3087 if (repeat_max != 1) cd->nopartial = TRUE;
3088
3089 /* Combine the op_type with the repeat_type */
3090
3091 repeat_type += op_type;
3092
3093 /* A minimum of zero is handled either as the special case * or ?, or as
3094 an UPTO, with the maximum given. */
3095
3096 if (repeat_min == 0)
3097 {
3098 if (repeat_max == -1) *code++ = OP_STAR + repeat_type;
3099 else if (repeat_max == 1) *code++ = OP_QUERY + repeat_type;
3100 else
3101 {
3102 *code++ = OP_UPTO + repeat_type;
3103 PUT2INC(code, 0, repeat_max);
3104 }
3105 }
3106
3107 /* A repeat minimum of 1 is optimized into some special cases. If the
3108 maximum is unlimited, we use OP_PLUS. Otherwise, the original item is
3109 left in place and, if the maximum is greater than 1, we use OP_UPTO with
3110 one less than the maximum. */
3111
3112 else if (repeat_min == 1)
3113 {
3114 if (repeat_max == -1)
3115 *code++ = OP_PLUS + repeat_type;
3116 else
3117 {
3118 code = oldcode; /* leave previous item in place */
3119 if (repeat_max == 1) goto END_REPEAT;
3120 *code++ = OP_UPTO + repeat_type;
3121 PUT2INC(code, 0, repeat_max - 1);
3122 }
3123 }
3124
3125 /* The case {n,n} is just an EXACT, while the general case {n,m} is
3126 handled as an EXACT followed by an UPTO. */
3127
3128 else
3129 {
3130 *code++ = OP_EXACT + op_type; /* NB EXACT doesn't have repeat_type */
3131 PUT2INC(code, 0, repeat_min);
3132
3133 /* If the maximum is unlimited, insert an OP_STAR. Before doing so,
3134 we have to insert the character for the previous code. For a repeated
3135 Unicode property match, there are two extra bytes that define the
3136 required property. In UTF-8 mode, long characters have their length in
3137 c, with the 0x80 bit as a flag. */
3138
3139 if (repeat_max < 0)
3140 {
3141 #ifdef SUPPORT_UTF8
3142 if (utf8 && c >= 128)
3143 {
3144 memcpy(code, utf8_char, c & 7);
3145 code += c & 7;
3146 }
3147 else
3148 #endif
3149 {
3150 *code++ = c;
3151 if (prop_type >= 0)
3152 {
3153 *code++ = prop_type;
3154 *code++ = prop_value;
3155 }
3156 }
3157 *code++ = OP_STAR + repeat_type;
3158 }
3159
3160 /* Else insert an UPTO if the max is greater than the min, again
3161 preceded by the character, for the previously inserted code. If the
3162 UPTO is just for 1 instance, we can use QUERY instead. */
3163
3164 else if (repeat_max != repeat_min)
3165 {
3166 #ifdef SUPPORT_UTF8
3167 if (utf8 && c >= 128)
3168 {
3169 memcpy(code, utf8_char, c & 7);
3170 code += c & 7;
3171 }
3172 else
3173 #endif
3174 *code++ = c;
3175 if (prop_type >= 0)
3176 {
3177 *code++ = prop_type;
3178 *code++ = prop_value;
3179 }
3180 repeat_max -= repeat_min;
3181
3182 if (repeat_max == 1)
3183 {
3184 *code++ = OP_QUERY + repeat_type;
3185 }
3186 else
3187 {
3188 *code++ = OP_UPTO + repeat_type;
3189 PUT2INC(code, 0, repeat_max);
3190 }
3191 }
3192 }
3193
3194 /* The character or character type itself comes last in all cases. */
3195
3196 #ifdef SUPPORT_UTF8
3197 if (utf8 && c >= 128)
3198 {
3199 memcpy(code, utf8_char, c & 7);
3200 code += c & 7;
3201 }
3202 else
3203 #endif
3204 *code++ = c;
3205
3206 /* For a repeated Unicode property match, there are two extra bytes that
3207 define the required property. */
3208
3209 #ifdef SUPPORT_UCP
3210 if (prop_type >= 0)
3211 {
3212 *code++ = prop_type;
3213 *code++ = prop_value;
3214 }
3215 #endif
3216 }
3217
3218 /* If previous was a character class or a back reference, we put the repeat
3219 stuff after it, but just skip the item if the repeat was {0,0}. */
3220
3221 else if (*previous == OP_CLASS ||
3222 *previous == OP_NCLASS ||
3223 #ifdef SUPPORT_UTF8
3224 *previous == OP_XCLASS ||
3225 #endif
3226 *previous == OP_REF)
3227 {
3228 if (repeat_max == 0)
3229 {
3230 code = previous;
3231 goto END_REPEAT;
3232 }
3233
3234 /* All real repeats make it impossible to handle partial matching (maybe
3235 one day we will be able to remove this restriction). */
3236
3237 if (repeat_max != 1) cd->nopartial = TRUE;
3238
3239 if (repeat_min == 0 && repeat_max == -1)
3240 *code++ = OP_CRSTAR + repeat_type;
3241 else if (repeat_min == 1 && repeat_max == -1)
3242 *code++ = OP_CRPLUS + repeat_type;
3243 else if (repeat_min == 0 && repeat_max == 1)
3244 *code++ = OP_CRQUERY + repeat_type;
3245 else
3246 {
3247 *code++ = OP_CRRANGE + repeat_type;
3248 PUT2INC(code, 0, repeat_min);
3249 if (repeat_max == -1) repeat_max = 0; /* 2-byte encoding for max */
3250 PUT2INC(code, 0, repeat_max);
3251 }
3252 }
3253
3254 /* If previous was a bracket group, we may have to replicate it in certain
3255 cases. */
3256
3257 else if (*previous == OP_BRA || *previous == OP_CBRA ||
3258 *previous == OP_ONCE || *previous == OP_COND)
3259 {
3260 register int i;
3261 int ketoffset = 0;
3262 int len = code - previous;
3263 uschar *bralink = NULL;
3264
3265 /* Repeating a DEFINE group is pointless */
3266
3267 if (*previous == OP_COND && previous[LINK_SIZE+1] == OP_DEF)
3268 {
3269 *errorcodeptr = ERR55;
3270 goto FAILED;
3271 }
3272
3273 /* This is a paranoid check to stop integer overflow later on */
3274
3275 if (len > MAX_DUPLENGTH)
3276 {
3277 *errorcodeptr = ERR50;
3278 goto FAILED;
3279 }
3280
3281 /* If the maximum repeat count is unlimited, find the end of the bracket
3282 by scanning through from the start, and compute the offset back to it
3283 from the current code pointer. There may be an OP_OPT setting following
3284 the final KET, so we can't find the end just by going back from the code
3285 pointer. */
3286
3287 if (repeat_max == -1)
3288 {
3289 register uschar *ket = previous;
3290 do ket += GET(ket, 1); while (*ket != OP_KET);
3291 ketoffset = code - ket;
3292 }
3293
3294 /* The case of a zero minimum is special because of the need to stick
3295 OP_BRAZERO in front of it, and because the group appears once in the
3296 data, whereas in other cases it appears the minimum number of times. For
3297 this reason, it is simplest to treat this case separately, as otherwise
3298 the code gets far too messy. There are several special subcases when the
3299 minimum is zero. */
3300
3301 if (repeat_min == 0)
3302 {
3303 /* If the maximum is also zero, we just omit the group from the output
3304 altogether. */
3305
3306 if (repeat_max == 0)
3307 {
3308 code = previous;
3309 goto END_REPEAT;
3310 }
3311
3312 /* If the maximum is 1 or unlimited, we just have to stick in the
3313 BRAZERO and do no more at this point. However, we do need to adjust
3314 any OP_RECURSE calls inside the group that refer to the group itself or
3315 any internal or forward referenced group, because the offset is from
3316 the start of the whole regex. Temporarily terminate the pattern while
3317 doing this. */
3318
3319 if (repeat_max <= 1)
3320 {
3321 *code = OP_END;
3322 adjust_recurse(previous, 1, utf8, cd, save_hwm);
3323 memmove(previous+1, previous, len);
3324 code++;
3325 *previous++ = OP_BRAZERO + repeat_type;
3326 }
3327
3328 /* If the maximum is greater than 1 and limited, we have to replicate
3329 in a nested fashion, sticking OP_BRAZERO before each set of brackets.
3330 The first one has to be handled carefully because it's the original
3331 copy, which has to be moved up. The remainder can be handled by code
3332 that is common with the non-zero minimum case below. We have to
3333 adjust the value or repeat_max, since one less copy is required. Once
3334 again, we may have to adjust any OP_RECURSE calls inside the group. */
3335
3336 else
3337 {
3338 int offset;
3339 *code = OP_END;
3340 adjust_recurse(previous, 2 + LINK_SIZE, utf8, cd, save_hwm);
3341 memmove(previous + 2 + LINK_SIZE, previous, len);
3342 code += 2 + LINK_SIZE;
3343 *previous++ = OP_BRAZERO + repeat_type;
3344 *previous++ = OP_BRA;
3345
3346 /* We chain together the bracket offset fields that have to be
3347 filled in later when the ends of the brackets are reached. */
3348
3349 offset = (bralink == NULL)? 0 : previous - bralink;
3350 bralink = previous;
3351 PUTINC(previous, 0, offset);
3352 }
3353
3354 repeat_max--;
3355 }
3356
3357 /* If the minimum is greater than zero, replicate the group as many
3358 times as necessary, and adjust the maximum to the number of subsequent
3359 copies that we need. If we set a first char from the group, and didn't
3360 set a required char, copy the latter from the former. If there are any
3361 forward reference subroutine calls in the group, there will be entries on
3362 the workspace list; replicate these with an appropriate increment. */
3363
3364 else
3365 {
3366 if (repeat_min > 1)
3367 {
3368 /* In the pre-compile phase, we don't actually do the replication. We
3369 just adjust the length as if we had. */
3370
3371 if (lengthptr != NULL)
3372 *lengthptr += (repeat_min - 1)*length_prevgroup;
3373
3374 /* This is compiling for real */
3375
3376 else
3377 {
3378 if (groupsetfirstbyte && reqbyte < 0) reqbyte = firstbyte;
3379 for (i = 1; i < repeat_min; i++)
3380 {
3381 uschar *hc;
3382 uschar *this_hwm = cd->hwm;
3383 memcpy(code, previous, len);
3384 for (hc = save_hwm; hc < this_hwm; hc += LINK_SIZE)
3385 {
3386 PUT(cd->hwm, 0, GET(hc, 0) + len);
3387 cd->hwm += LINK_SIZE;
3388 }
3389 save_hwm = this_hwm;
3390 code += len;
3391 }
3392 }
3393 }
3394
3395 if (repeat_max > 0) repeat_max -= repeat_min;
3396 }
3397
3398 /* This code is common to both the zero and non-zero minimum cases. If
3399 the maximum is limited, it replicates the group in a nested fashion,
3400 remembering the bracket starts on a stack. In the case of a zero minimum,
3401 the first one was set up above. In all cases the repeat_max now specifies
3402 the number of additional copies needed. Again, we must remember to
3403 replicate entries on the forward reference list. */
3404
3405 if (repeat_max >= 0)
3406 {
3407 /* In the pre-compile phase, we don't actually do the replication. We
3408 just adjust the length as if we had. For each repetition we must add 1
3409 to the length for BRAZERO and for all but the last repetition we must
3410 add 2 + 2*LINKSIZE to allow for the nesting that occurs. */
3411
3412 if (lengthptr != NULL && repeat_max > 0)
3413 *lengthptr += repeat_max * (length_prevgroup + 1 + 2 + 2*LINK_SIZE) -
3414 2 - 2*LINK_SIZE; /* Last one doesn't nest */
3415
3416 /* This is compiling for real */
3417
3418 else for (i = repeat_max - 1; i >= 0; i--)
3419 {
3420 uschar *hc;
3421 uschar *this_hwm = cd->hwm;
3422
3423 *code++ = OP_BRAZERO + repeat_type;
3424
3425 /* All but the final copy start a new nesting, maintaining the
3426 chain of brackets outstanding. */
3427
3428 if (i != 0)
3429 {
3430 int offset;
3431 *code++ = OP_BRA;
3432 offset = (bralink == NULL)? 0 : code - bralink;
3433 bralink = code;
3434 PUTINC(code, 0, offset);
3435 }
3436
3437 memcpy(code, previous, len);
3438 for (hc = save_hwm; hc < this_hwm; hc += LINK_SIZE)
3439 {
3440 PUT(cd->hwm, 0, GET(hc, 0) + len + ((i != 0)? 2+LINK_SIZE : 1));
3441 cd->hwm += LINK_SIZE;
3442 }
3443 save_hwm = this_hwm;
3444 code += len;
3445 }
3446
3447 /* Now chain through the pending brackets, and fill in their length
3448 fields (which are holding the chain links pro tem). */
3449
3450 while (bralink != NULL)
3451 {
3452 int oldlinkoffset;
3453 int offset = code - bralink + 1;
3454 uschar *bra = code - offset;
3455 oldlinkoffset = GET(bra, 1);
3456 bralink = (oldlinkoffset == 0)? NULL : bralink - oldlinkoffset;
3457 *code++ = OP_KET;
3458 PUTINC(code, 0, offset);
3459 PUT(bra, 1, offset);
3460 }
3461 }
3462
3463 /* If the maximum is unlimited, set a repeater in the final copy. We
3464 can't just offset backwards from the current code point, because we
3465 don't know if there's been an options resetting after the ket. The
3466 correct offset was computed above.
3467
3468 Then, when we are doing the actual compile phase, check to see whether
3469 this group is a non-atomic one that could match an empty string. If so,
3470 convert the initial operator to the S form (e.g. OP_BRA -> OP_SBRA) so
3471 that runtime checking can be done. [This check is also applied to
3472 atomic groups at runtime, but in a different way.] */
3473
3474 else
3475 {
3476 uschar *ketcode = code - ketoffset;
3477 uschar *bracode = ketcode - GET(ketcode, 1);
3478 *ketcode = OP_KETRMAX + repeat_type;
3479 if (lengthptr == NULL && *bracode != OP_ONCE)
3480 {
3481 uschar *scode = bracode;
3482 do
3483 {
3484 if (could_be_empty_branch(scode, ketcode, utf8))
3485 {
3486 *bracode += OP_SBRA - OP_BRA;
3487 break;
3488 }
3489 scode += GET(scode, 1);
3490 }
3491 while (*scode == OP_ALT);
3492 }
3493 }
3494 }
3495
3496 /* Else there's some kind of shambles */
3497
3498 else
3499 {
3500 *errorcodeptr = ERR11;
3501 goto FAILED;
3502 }
3503
3504 /* If the character following a repeat is '+', or if certain optimization
3505 tests above succeeded, possessive_quantifier is TRUE. For some of the
3506 simpler opcodes, there is an special alternative opcode for this. For
3507 anything else, we wrap the entire repeated item inside OP_ONCE brackets.
3508 The '+' notation is just syntactic sugar, taken from Sun's Java package,
3509 but the special opcodes can optimize it a bit. The repeated item starts at
3510 tempcode, not at previous, which might be the first part of a string whose
3511 (former) last char we repeated.
3512
3513 Possessifying an 'exact' quantifier has no effect, so we can ignore it. But
3514 an 'upto' may follow. We skip over an 'exact' item, and then test the
3515 length of what remains before proceeding. */
3516
3517 if (possessive_quantifier)
3518 {
3519 int len;
3520 if (*tempcode == OP_EXACT || *tempcode == OP_TYPEEXACT ||
3521 *tempcode == OP_NOTEXACT)
3522 tempcode += _pcre_OP_lengths[*tempcode];
3523 len = code - tempcode;
3524 if (len > 0) switch (*tempcode)
3525 {
3526 case OP_STAR: *tempcode = OP_POSSTAR; break;
3527 case OP_PLUS: *tempcode = OP_POSPLUS; break;
3528 case OP_QUERY: *tempcode = OP_POSQUERY; break;
3529 case OP_UPTO: *tempcode = OP_POSUPTO; break;
3530
3531 case OP_TYPESTAR: *tempcode = OP_TYPEPOSSTAR; break;
3532 case OP_TYPEPLUS: *tempcode = OP_TYPEPOSPLUS; break;
3533 case OP_TYPEQUERY: *tempcode = OP_TYPEPOSQUERY; break;
3534 case OP_TYPEUPTO: *tempcode = OP_TYPEPOSUPTO; break;
3535
3536 case OP_NOTSTAR: *tempcode = OP_NOTPOSSTAR; break;
3537 case OP_NOTPLUS: *tempcode = OP_NOTPOSPLUS; break;
3538 case OP_NOTQUERY: *tempcode = OP_NOTPOSQUERY; break;
3539 case OP_NOTUPTO: *tempcode = OP_NOTPOSUPTO; break;
3540
3541 default:
3542 memmove(tempcode + 1+LINK_SIZE, tempcode, len);
3543 code += 1 + LINK_SIZE;
3544 len += 1 + LINK_SIZE;
3545 tempcode[0] = OP_ONCE;
3546 *code++ = OP_KET;
3547 PUTINC(code, 0, len);
3548 PUT(tempcode, 1, len);
3549 break;
3550 }
3551 }
3552
3553 /* In all case we no longer have a previous item. We also set the
3554 "follows varying string" flag for subsequently encountered reqbytes if
3555 it isn't already set and we have just passed a varying length item. */
3556
3557 END_REPEAT:
3558 previous = NULL;
3559 cd->req_varyopt |= reqvary;
3560 break;
3561
3562
3563 /* ===================================================================*/
3564 /* Start of nested parenthesized sub-expression, or comment or lookahead or
3565 lookbehind or option setting or condition or all the other extended
3566 parenthesis forms. First deal with the specials; all are introduced by ?,
3567 and the appearance of any of them means that this is not a capturing
3568 group. */
3569
3570 case '(':
3571 newoptions = options;
3572 skipbytes = 0;
3573 bravalue = OP_CBRA;
3574 save_hwm = cd->hwm;
3575
3576 if (*(++ptr) == '?')
3577 {
3578 int i, set, unset, namelen;
3579 int *optset;
3580 const uschar *name;
3581 uschar *slot;
3582
3583 switch (*(++ptr))
3584 {
3585 case '#': /* Comment; skip to ket */
3586 ptr++;
3587 while (*ptr != 0 && *ptr != ')') ptr++;
3588 if (*ptr == 0)
3589 {
3590 *errorcodeptr = ERR18;
3591 goto FAILED;
3592 }
3593 continue;
3594
3595
3596 /* ------------------------------------------------------------ */
3597 case ':': /* Non-capturing bracket */
3598 bravalue = OP_BRA;
3599 ptr++;
3600 break;
3601
3602
3603 /* ------------------------------------------------------------ */
3604 case '(':
3605 bravalue = OP_COND; /* Conditional group */
3606
3607 /* A condition can be an assertion, a number (referring to a numbered
3608 group), a name (referring to a named group), or 'R', referring to
3609 recursion. R<digits> and R&name are also permitted for recursion tests.
3610
3611 There are several syntaxes for testing a named group: (?(name)) is used
3612 by Python; Perl 5.10 onwards uses (?(<name>) or (?('name')).
3613
3614 There are two unfortunate ambiguities, caused by history. (a) 'R' can
3615 be the recursive thing or the name 'R' (and similarly for 'R' followed
3616 by digits), and (b) a number could be a name that consists of digits.
3617 In both cases, we look for a name first; if not found, we try the other
3618 cases. */
3619
3620 /* For conditions that are assertions, check the syntax, and then exit
3621 the switch. This will take control down to where bracketed groups,
3622 including assertions, are processed. */
3623
3624 if (ptr[1] == '?' && (ptr[2] == '=' || ptr[2] == '!' || ptr[2] == '<'))
3625 break;
3626
3627 /* Most other conditions use OP_CREF (a couple change to OP_RREF
3628 below), and all need to skip 3 bytes at the start of the group. */
3629
3630 code[1+LINK_SIZE] = OP_CREF;
3631 skipbytes = 3;
3632 refsign = -1;
3633
3634 /* Check for a test for recursion in a named group. */
3635
3636 if (ptr[1] == 'R' && ptr[2] == '&')
3637 {
3638 terminator = -1;
3639 ptr += 2;
3640 code[1+LINK_SIZE] = OP_RREF; /* Change the type of test */
3641 }
3642
3643 /* Check for a test for a named group's having been set, using the Perl
3644 syntax (?(<name>) or (?('name') */
3645
3646 else if (ptr[1] == '<')
3647 {
3648 terminator = '>';
3649 ptr++;
3650 }
3651 else if (ptr[1] == '\'')
3652 {
3653 terminator = '\'';
3654 ptr++;
3655 }
3656 else
3657 {
3658 terminator = 0;
3659 if (ptr[1] == '-' || ptr[1] == '+') refsign = *(++ptr);
3660 }
3661
3662 /* We now expect to read a name; any thing else is an error */
3663
3664 if ((cd->ctypes[ptr[1]] & ctype_word) == 0)
3665 {
3666 ptr += 1; /* To get the right offset */
3667 *errorcodeptr = ERR28;
3668 goto FAILED;
3669 }
3670
3671 /* Read the name, but also get it as a number if it's all digits */
3672
3673 recno = 0;
3674 name = ++ptr;
3675 while ((cd->ctypes[*ptr] & ctype_word) != 0)
3676 {
3677 if (recno >= 0)
3678 recno = ((digitab[*ptr] & ctype_digit) != 0)?
3679 recno * 10 + *ptr - '0' : -1;
3680 ptr++;
3681 }
3682 namelen = ptr - name;
3683
3684 if ((terminator > 0 && *ptr++ != terminator) || *ptr++ != ')')
3685 {
3686 ptr--; /* Error offset */
3687 *errorcodeptr = ERR26;
3688 goto FAILED;
3689 }
3690
3691 /* Do no further checking in the pre-compile phase. */
3692
3693 if (lengthptr != NULL) break;
3694
3695 /* In the real compile we do the work of looking for the actual
3696 reference. If the string started with "+" or "-" we require the rest to
3697 be digits, in which case recno will be set. */
3698
3699 if (refsign > 0)
3700 {
3701 if (recno <= 0)
3702 {
3703 *errorcodeptr = ERR58;
3704 goto FAILED;
3705 }
3706 if (refsign == '-')
3707 {
3708 recno = cd->bracount - recno + 1;
3709 if (recno <= 0)
3710 {
3711 *errorcodeptr = ERR15;
3712 goto FAILED;
3713 }
3714 }
3715 else recno += cd->bracount;
3716 PUT2(code, 2+LINK_SIZE, recno);
3717 break;
3718 }
3719
3720 /* Otherwise (did not start with "+" or "-"), start by looking for the
3721 name. */
3722
3723 slot = cd->name_table;
3724 for (i = 0; i < cd->names_found; i++)
3725 {
3726 if (strncmp((char *)name, (char *)slot+2, namelen) == 0) break;
3727 slot += cd->name_entry_size;
3728 }
3729
3730 /* Found a previous named subpattern */
3731
3732 if (i < cd->names_found)
3733 {
3734 recno = GET2(slot, 0);
3735 PUT2(code, 2+LINK_SIZE, recno);
3736 }
3737
3738 /* Search the pattern for a forward reference */
3739
3740 else if ((i = find_parens(ptr, cd->bracount, name, namelen,
3741 (options & PCRE_EXTENDED) != 0)) > 0)
3742 {
3743 PUT2(code, 2+LINK_SIZE, i);
3744 }
3745
3746 /* If terminator == 0 it means that the name followed directly after
3747 the opening parenthesis [e.g. (?(abc)...] and in this case there are
3748 some further alternatives to try. For the cases where terminator != 0
3749 [things like (?(<name>... or (?('name')... or (?(R&name)... ] we have
3750 now checked all the possibilities, so give an error. */
3751
3752 else if (terminator != 0)
3753 {
3754 *errorcodeptr = ERR15;
3755 goto FAILED;
3756 }
3757
3758 /* Check for (?(R) for recursion. Allow digits after R to specify a
3759 specific group number. */
3760
3761 else if (*name == 'R')
3762 {
3763 recno = 0;
3764 for (i = 1; i < namelen; i++)
3765 {
3766 if ((digitab[name[i]] & ctype_digit) == 0)
3767 {
3768 *errorcodeptr = ERR15;
3769 goto FAILED;
3770 }
3771 recno = recno * 10 + name[i] - '0';
3772 }
3773 if (recno == 0) recno = RREF_ANY;
3774 code[1+LINK_SIZE] = OP_RREF; /* Change test type */
3775 PUT2(code, 2+LINK_SIZE, recno);
3776 }
3777
3778 /* Similarly, check for the (?(DEFINE) "condition", which is always
3779 false. */
3780
3781 else if (namelen == 6 && strncmp((char *)name, "DEFINE", 6) == 0)
3782 {
3783 code[1+LINK_SIZE] = OP_DEF;
3784 skipbytes = 1;
3785 }
3786
3787 /* Check for the "name" actually being a subpattern number. */
3788
3789 else if (recno > 0)
3790 {
3791 PUT2(code, 2+LINK_SIZE, recno);
3792 }
3793
3794 /* Either an unidentified subpattern, or a reference to (?(0) */
3795
3796 else
3797 {
3798 *errorcodeptr = (recno == 0)? ERR35: ERR15;
3799 goto FAILED;
3800 }
3801 break;
3802
3803
3804 /* ------------------------------------------------------------ */
3805 case '=': /* Positive lookahead */
3806 bravalue = OP_ASSERT;
3807 ptr++;
3808 break;
3809
3810
3811 /* ------------------------------------------------------------ */
3812 case '!': /* Negative lookahead */
3813 bravalue = OP_ASSERT_NOT;
3814 ptr++;
3815 break;
3816
3817
3818 /* ------------------------------------------------------------ */
3819 case '<': /* Lookbehind or named define */
3820 switch (ptr[1])
3821 {
3822 case '=': /* Positive lookbehind */
3823 bravalue = OP_ASSERTBACK;
3824 ptr += 2;
3825 break;
3826
3827 case '!': /* Negative lookbehind */
3828 bravalue = OP_ASSERTBACK_NOT;
3829 ptr += 2;
3830 break;
3831
3832 default: /* Could be name define, else bad */
3833 if ((cd->ctypes[ptr[1]] & ctype_word) != 0) goto DEFINE_NAME;
3834 ptr++; /* Correct offset for error */
3835 *errorcodeptr = ERR24;
3836 goto FAILED;
3837 }
3838 break;
3839
3840
3841 /* ------------------------------------------------------------ */
3842 case '>': /* One-time brackets */
3843 bravalue = OP_ONCE;
3844 ptr++;
3845 break;
3846
3847
3848 /* ------------------------------------------------------------ */
3849 case 'C': /* Callout - may be followed by digits; */
3850 previous_callout = code; /* Save for later completion */
3851 after_manual_callout = 1; /* Skip one item before completing */
3852 *code++ = OP_CALLOUT;
3853 {
3854 int n = 0;
3855 while ((digitab[*(++ptr)] & ctype_digit) != 0)
3856 n = n * 10 + *ptr - '0';
3857 if (*ptr != ')')
3858 {
3859 *errorcodeptr = ERR39;
3860 goto FAILED;
3861 }
3862 if (n > 255)
3863 {
3864 *errorcodeptr = ERR38;
3865 goto FAILED;
3866 }
3867 *code++ = n;
3868 PUT(code, 0, ptr - cd->start_pattern + 1); /* Pattern offset */
3869 PUT(code, LINK_SIZE, 0); /* Default length */
3870 code += 2 * LINK_SIZE;
3871 }
3872 previous = NULL;
3873 continue;
3874
3875
3876 /* ------------------------------------------------------------ */
3877 case 'P': /* Python-style named subpattern handling */
3878 if (*(++ptr) == '=' || *ptr == '>') /* Reference or recursion */
3879 {
3880 is_recurse = *ptr == '>';
3881 terminator = ')';
3882 goto NAMED_REF_OR_RECURSE;
3883 }
3884 else if (*ptr != '<') /* Test for Python-style definition */
3885 {
3886 *errorcodeptr = ERR41;
3887 goto FAILED;
3888 }
3889 /* Fall through to handle (?P< as (?< is handled */
3890
3891
3892 /* ------------------------------------------------------------ */
3893 DEFINE_NAME: /* Come here from (?< handling */
3894 case '\'':
3895 {
3896 terminator = (*ptr == '<')? '>' : '\'';
3897 name = ++ptr;
3898
3899 while ((cd->ctypes[*ptr] & ctype_word) != 0) ptr++;
3900 namelen = ptr - name;
3901
3902 /* In the pre-compile phase, just do a syntax check. */
3903
3904 if (lengthptr != NULL)
3905 {
3906 if (*ptr != terminator)
3907 {
3908 *errorcodeptr = ERR42;
3909 goto FAILED;
3910 }
3911 if (cd->names_found >= MAX_NAME_COUNT)
3912 {
3913 *errorcodeptr = ERR49;
3914 goto FAILED;
3915 }
3916 if (namelen + 3 > cd->name_entry_size)
3917 {
3918 cd->name_entry_size = namelen + 3;
3919 if (namelen > MAX_NAME_SIZE)
3920 {
3921 *errorcodeptr = ERR48;
3922 goto FAILED;
3923 }
3924 }
3925 }
3926
3927 /* In the real compile, create the entry in the table */
3928
3929 else
3930 {
3931 slot = cd->name_table;
3932 for (i = 0; i < cd->names_found; i++)
3933 {
3934 int crc = memcmp(name, slot+2, namelen);
3935 if (crc == 0)
3936 {
3937 if (slot[2+namelen] == 0)
3938 {
3939 if ((options & PCRE_DUPNAMES) == 0)
3940 {
3941 *errorcodeptr = ERR43;
3942 goto FAILED;
3943 }
3944 }
3945 else crc = -1; /* Current name is substring */
3946 }
3947 if (crc < 0)
3948 {
3949 memmove(slot + cd->name_entry_size, slot,
3950 (cd->names_found - i) * cd->name_entry_size);
3951 break;
3952 }
3953 slot += cd->name_entry_size;
3954 }
3955
3956 PUT2(slot, 0, cd->bracount + 1);
3957 memcpy(slot + 2, name, namelen);
3958 slot[2+namelen] = 0;
3959 }
3960 }
3961
3962 /* In both cases, count the number of names we've encountered. */
3963
3964 ptr++; /* Move past > or ' */
3965 cd->names_found++;
3966 goto NUMBERED_GROUP;
3967
3968
3969 /* ------------------------------------------------------------ */
3970 case '&': /* Perl recursion/subroutine syntax */
3971 terminator = ')';
3972 is_recurse = TRUE;
3973 /* Fall through */
3974
3975 /* We come here from the Python syntax above that handles both
3976 references (?P=name) and recursion (?P>name), as well as falling
3977 through from the Perl recursion syntax (?&name). */
3978
3979 NAMED_REF_OR_RECURSE:
3980 name = ++ptr;
3981 while ((cd->ctypes[*ptr] & ctype_word) != 0) ptr++;
3982 namelen = ptr - name;
3983
3984 /* In the pre-compile phase, do a syntax check and set a dummy
3985 reference number. */
3986
3987 if (lengthptr != NULL)
3988 {
3989 if (*ptr != terminator)
3990 {
3991 *errorcodeptr = ERR42;
3992 goto FAILED;
3993 }
3994 if (namelen > MAX_NAME_SIZE)
3995 {
3996 *errorcodeptr = ERR48;
3997 goto FAILED;
3998 }
3999 recno = 0;
4000 }
4001
4002 /* In the real compile, seek the name in the table */
4003
4004 else
4005 {
4006 slot = cd->name_table;
4007 for (i = 0; i < cd->names_found; i++)
4008 {
4009 if (strncmp((char *)name, (char *)slot+2, namelen) == 0) break;
4010 slot += cd->name_entry_size;
4011 }
4012
4013 if (i < cd->names_found) /* Back reference */
4014 {
4015 recno = GET2(slot, 0);
4016 }
4017 else if ((recno = /* Forward back reference */
4018 find_parens(ptr, cd->bracount, name, namelen,
4019 (options & PCRE_EXTENDED) != 0)) <= 0)
4020 {
4021 *errorcodeptr = ERR15;
4022 goto FAILED;
4023 }
4024 }
4025
4026 /* In both phases, we can now go to the code than handles numerical
4027 recursion or backreferences. */
4028
4029 if (is_recurse) goto HANDLE_RECURSION;
4030 else goto HANDLE_REFERENCE;
4031
4032
4033 /* ------------------------------------------------------------ */
4034 case 'R': /* Recursion */
4035 ptr++; /* Same as (?0) */
4036 /* Fall through */
4037
4038
4039 /* ------------------------------------------------------------ */
4040 case '-': case '+':
4041 case '0': case '1': case '2': case '3': case '4': /* Recursion or */
4042 case '5': case '6': case '7': case '8': case '9': /* subroutine */
4043 {
4044 const uschar *called;
4045
4046 if ((refsign = *ptr) == '+') ptr++;
4047 else if (refsign == '-')
4048 {
4049 if ((digitab[ptr[1]] & ctype_digit) == 0)
4050 goto OTHER_CHAR_AFTER_QUERY;
4051 ptr++;
4052 }
4053
4054 recno = 0;
4055 while((digitab[*ptr] & ctype_digit) != 0)
4056 recno = recno * 10 + *ptr++ - '0';
4057
4058 if (*ptr != ')')
4059 {
4060 *errorcodeptr = ERR29;
4061 goto FAILED;
4062 }
4063
4064 if (refsign == '-')
4065 {
4066 if (recno == 0)
4067 {
4068 *errorcodeptr = ERR58;
4069 goto FAILED;
4070 }
4071 recno = cd->bracount - recno + 1;
4072 if (recno <= 0)
4073 {
4074 *errorcodeptr = ERR15;
4075 goto FAILED;
4076 }
4077 }
4078 else if (refsign == '+')
4079 {
4080 if (recno == 0)
4081 {
4082 *errorcodeptr = ERR58;
4083 goto FAILED;
4084 }
4085 recno += cd->bracount;
4086 }
4087
4088 /* Come here from code above that handles a named recursion */
4089
4090 HANDLE_RECURSION:
4091
4092 previous = code;
4093 called = cd->start_code;
4094
4095 /* When we are actually compiling, find the bracket that is being
4096 referenced. Temporarily end the regex in case it doesn't exist before
4097 this point. If we end up with a forward reference, first check that
4098 the bracket does occur later so we can give the error (and position)
4099 now. Then remember this forward reference in the workspace so it can
4100 be filled in at the end. */
4101
4102 if (lengthptr == NULL)
4103 {
4104 *code = OP_END;
4105 if (recno != 0) called = find_bracket(cd->start_code, utf8, recno);
4106
4107 /* Forward reference */
4108
4109 if (called == NULL)
4110 {
4111 if (find_parens(ptr, cd->bracount, NULL, recno,
4112 (options & PCRE_EXTENDED) != 0) < 0)
4113 {
4114 *errorcodeptr = ERR15;
4115 goto FAILED;
4116 }
4117 called = cd->start_code + recno;
4118 PUTINC(cd->hwm, 0, code + 2 + LINK_SIZE - cd->start_code);
4119 }
4120
4121 /* If not a forward reference, and the subpattern is still open,
4122 this is a recursive call. We check to see if this is a left
4123 recursion that could loop for ever, and diagnose that case. */
4124
4125 else if (GET(called, 1) == 0 &&
4126 could_be_empty(called, code, bcptr, utf8))
4127 {
4128 *errorcodeptr = ERR40;
4129 goto FAILED;
4130 }
4131 }
4132
4133 /* Insert the recursion/subroutine item, automatically wrapped inside
4134 "once" brackets. Set up a "previous group" length so that a
4135 subsequent quantifier will work. */
4136
4137 *code = OP_ONCE;
4138 PUT(code, 1, 2 + 2*LINK_SIZE);
4139 code += 1 + LINK_SIZE;
4140
4141 *code = OP_RECURSE;
4142 PUT(code, 1, called - cd->start_code);
4143 code += 1 + LINK_SIZE;
4144
4145 *code = OP_KET;
4146 PUT(code, 1, 2 + 2*LINK_SIZE);
4147 code += 1 + LINK_SIZE;
4148
4149 length_prevgroup = 3 + 3*LINK_SIZE;
4150 }
4151
4152 /* Can't determine a first byte now */
4153
4154 if (firstbyte == REQ_UNSET) firstbyte = REQ_NONE;
4155 continue;
4156
4157
4158 /* ------------------------------------------------------------ */
4159 default: /* Other characters: check option setting */
4160 OTHER_CHAR_AFTER_QUERY:
4161 set = unset = 0;
4162 optset = &set;
4163
4164 while (*ptr != ')' && *ptr != ':')
4165 {
4166 switch (*ptr++)
4167 {
4168 case '-': optset = &unset; break;
4169
4170 case 'J': /* Record that it changed in the external options */
4171 *optset |= PCRE_DUPNAMES;
4172 cd->external_options |= PCRE_JCHANGED;
4173 break;
4174
4175 case 'i': *optset |= PCRE_CASELESS; break;
4176 case 'm': *optset |= PCRE_MULTILINE; break;
4177 case 's': *optset |= PCRE_DOTALL; break;
4178 case 'x': *optset |= PCRE_EXTENDED; break;
4179 case 'U': *optset |= PCRE_UNGREEDY; break;
4180 case 'X': *optset |= PCRE_EXTRA; break;
4181
4182 default: *errorcodeptr = ERR12;
4183 ptr--; /* Correct the offset */
4184 goto FAILED;
4185 }
4186 }
4187
4188 /* Set up the changed option bits, but don't change anything yet. */
4189
4190 newoptions = (options | set) & (~unset);
4191
4192 /* If the options ended with ')' this is not the start of a nested
4193 group with option changes, so the options change at this level. If this
4194 item is right at the start of the pattern, the options can be
4195 abstracted and made external in the pre-compile phase, and ignored in
4196 the compile phase. This can be helpful when matching -- for instance in
4197 caseless checking of required bytes.
4198
4199 If the code pointer is not (cd->start_code + 1 + LINK_SIZE), we are
4200 definitely *not* at the start of the pattern because something has been
4201 compiled. In the pre-compile phase, however, the code pointer can have
4202 that value after the start, because it gets reset as code is discarded
4203 during the pre-compile. However, this can happen only at top level - if
4204 we are within parentheses, the starting BRA will still be present. At
4205 any parenthesis level, the length value can be used to test if anything
4206 has been compiled at that level. Thus, a test for both these conditions
4207 is necessary to ensure we correctly detect the start of the pattern in
4208 both phases.
4209
4210 If we are not at the pattern start, compile code to change the ims
4211 options if this setting actually changes any of them. We also pass the
4212 new setting back so that it can be put at the start of any following
4213 branches, and when this group ends (if we are in a group), a resetting
4214 item can be compiled. */
4215
4216 if (*ptr == ')')
4217 {
4218 if (code == cd->start_code + 1 + LINK_SIZE &&
4219 (lengthptr == NULL || *lengthptr == 2 + 2*LINK_SIZE))
4220 {
4221 cd->external_options = newoptions;
4222 options = newoptions;
4223 }
4224 else
4225 {
4226 if ((options & PCRE_IMS) != (newoptions & PCRE_IMS))
4227 {
4228 *code++ = OP_OPT;
4229 *code++ = newoptions & PCRE_IMS;
4230 }
4231
4232 /* Change options at this level, and pass them back for use
4233 in subsequent branches. Reset the greedy defaults and the case
4234 value for firstbyte and reqbyte. */
4235
4236 *optionsptr = options = newoptions;
4237 greedy_default = ((newoptions & PCRE_UNGREEDY) != 0);
4238 greedy_non_default = greedy_default ^ 1;
4239 req_caseopt = ((options & PCRE_CASELESS) != 0)? REQ_CASELESS : 0;
4240 }
4241
4242 previous = NULL; /* This item can't be repeated */
4243 continue; /* It is complete */
4244 }
4245
4246 /* If the options ended with ':' we are heading into a nested group
4247 with possible change of options. Such groups are non-capturing and are
4248 not assertions of any kind. All we need to do is skip over the ':';
4249 the newoptions value is handled below. */
4250
4251 bravalue = OP_BRA;
4252 ptr++;
4253 } /* End of switch for character following (? */
4254 } /* End of (? handling */
4255
4256 /* Opening parenthesis not followed by '?'. If PCRE_NO_AUTO_CAPTURE is set,
4257 all unadorned brackets become non-capturing and behave like (?:...)
4258 brackets. */
4259
4260 else if ((options & PCRE_NO_AUTO_CAPTURE) != 0)
4261 {
4262 bravalue = OP_BRA;
4263 }
4264
4265 /* Else we have a capturing group. */
4266
4267 else
4268 {
4269 NUMBERED_GROUP:
4270 cd->bracount += 1;
4271 PUT2(code, 1+LINK_SIZE, cd->bracount);
4272 skipbytes = 2;
4273 }
4274
4275 /* Process nested bracketed regex. Assertions may not be repeated, but
4276 other kinds can be. All their opcodes are >= OP_ONCE. We copy code into a
4277 non-register variable in order to be able to pass its address because some
4278 compilers complain otherwise. Pass in a new setting for the ims options if
4279 they have changed. */
4280
4281 previous = (bravalue >= OP_ONCE)? code : NULL;
4282 *code = bravalue;
4283 tempcode = code;
4284 tempreqvary = cd->req_varyopt; /* Save value before bracket */
4285 length_prevgroup = 0; /* Initialize for pre-compile phase */
4286
4287 if (!compile_regex(
4288 newoptions, /* The complete new option state */
4289 options & PCRE_IMS, /* The previous ims option state */
4290 &tempcode, /* Where to put code (updated) */
4291 &ptr, /* Input pointer (updated) */
4292 errorcodeptr, /* Where to put an error message */
4293 (bravalue == OP_ASSERTBACK ||
4294 bravalue == OP_ASSERTBACK_NOT), /* TRUE if back assert */
4295 skipbytes, /* Skip over bracket number */
4296 &subfirstbyte, /* For possible first char */
4297 &subreqbyte, /* For possible last char */
4298 bcptr, /* Current branch chain */
4299 cd, /* Tables block */
4300 (lengthptr == NULL)? NULL : /* Actual compile phase */
4301 &length_prevgroup /* Pre-compile phase */
4302 ))
4303 goto FAILED;
4304
4305 /* At the end of compiling, code is still pointing to the start of the
4306 group, while tempcode has been updated to point past the end of the group
4307 and any option resetting that may follow it. The pattern pointer (ptr)
4308 is on the bracket. */
4309
4310 /* If this is a conditional bracket, check that there are no more than
4311 two branches in the group, or just one if it's a DEFINE group. */
4312
4313 if (bravalue == OP_COND)
4314 {
4315 uschar *tc = code;
4316 int condcount = 0;
4317
4318 do {
4319 condcount++;
4320 tc += GET(tc,1);
4321 }
4322 while (*tc != OP_KET);
4323
4324 /* A DEFINE group is never obeyed inline (the "condition" is always
4325 false). It must have only one branch. */
4326
4327 if (code[LINK_SIZE+1] == OP_DEF)
4328 {
4329 if (condcount > 1)
4330 {
4331 *errorcodeptr = ERR54;
4332 goto FAILED;
4333 }
4334 bravalue = OP_DEF; /* Just a flag to suppress char handling below */
4335 }
4336
4337 /* A "normal" conditional group. If there is just one branch, we must not
4338 make use of its firstbyte or reqbyte, because this is equivalent to an
4339 empty second branch. */
4340
4341 else
4342 {
4343 if (condcount > 2)
4344 {
4345 *errorcodeptr = ERR27;
4346 goto FAILED;
4347 }
4348 if (condcount == 1) subfirstbyte = subreqbyte = REQ_NONE;
4349 }
4350 }
4351
4352 /* Error if hit end of pattern */
4353
4354 if (*ptr != ')')
4355 {
4356 *errorcodeptr = ERR14;
4357 goto FAILED;
4358 }
4359
4360 /* In the pre-compile phase, update the length by the length of the nested
4361 group, less the brackets at either end. Then reduce the compiled code to
4362 just the brackets so that it doesn't use much memory if it is duplicated by
4363 a quantifier. */
4364
4365 if (lengthptr != NULL)
4366 {
4367 *lengthptr += length_prevgroup - 2 - 2*LINK_SIZE;
4368 code++;
4369 PUTINC(code, 0, 1 + LINK_SIZE);
4370 *code++ = OP_KET;
4371 PUTINC(code, 0, 1 + LINK_SIZE);
4372 }
4373
4374 /* Otherwise update the main code pointer to the end of the group. */
4375
4376 else code = tempcode;
4377
4378 /* For a DEFINE group, required and first character settings are not
4379 relevant. */
4380
4381 if (bravalue == OP_DEF) break;
4382
4383 /* Handle updating of the required and first characters for other types of
4384 group. Update for normal brackets of all kinds, and conditions with two
4385 branches (see code above). If the bracket is followed by a quantifier with
4386 zero repeat, we have to back off. Hence the definition of zeroreqbyte and
4387 zerofirstbyte outside the main loop so that they can be accessed for the
4388 back off. */
4389
4390 zeroreqbyte = reqbyte;
4391 zerofirstbyte = firstbyte;
4392 groupsetfirstbyte = FALSE;
4393
4394 if (bravalue >= OP_ONCE)
4395 {
4396 /* If we have not yet set a firstbyte in this branch, take it from the
4397 subpattern, remembering that it was set here so that a repeat of more
4398 than one can replicate it as reqbyte if necessary. If the subpattern has
4399 no firstbyte, set "none" for the whole branch. In both cases, a zero
4400 repeat forces firstbyte to "none". */
4401
4402 if (firstbyte == REQ_UNSET)
4403 {
4404 if (subfirstbyte >= 0)
4405 {
4406 firstbyte = subfirstbyte;
4407 groupsetfirstbyte = TRUE;
4408 }
4409 else firstbyte = REQ_NONE;
4410 zerofirstbyte = REQ_NONE;
4411 }
4412
4413 /* If firstbyte was previously set, convert the subpattern's firstbyte
4414 into reqbyte if there wasn't one, using the vary flag that was in
4415 existence beforehand. */
4416
4417 else if (subfirstbyte >= 0 && subreqbyte < 0)
4418 subreqbyte = subfirstbyte | tempreqvary;
4419
4420 /* If the subpattern set a required byte (or set a first byte that isn't
4421 really the first byte - see above), set it. */
4422
4423 if (subreqbyte >= 0) reqbyte = subreqbyte;
4424 }
4425
4426 /* For a forward assertion, we take the reqbyte, if set. This can be
4427 helpful if the pattern that follows the assertion doesn't set a different
4428 char. For example, it's useful for /(?=abcde).+/. We can't set firstbyte
4429 for an assertion, however because it leads to incorrect effect for patterns
4430 such as /(?=a)a.+/ when the "real" "a" would then become a reqbyte instead
4431 of a firstbyte. This is overcome by a scan at the end if there's no
4432 firstbyte, looking for an asserted first char. */
4433
4434 else if (bravalue == OP_ASSERT && subreqbyte >= 0) reqbyte = subreqbyte;
4435 break; /* End of processing '(' */
4436
4437
4438 /* ===================================================================*/
4439 /* Handle metasequences introduced by \. For ones like \d, the ESC_ values
4440 are arranged to be the negation of the corresponding OP_values. For the
4441 back references, the values are ESC_REF plus the reference number. Only
4442 back references and those types that consume a character may be repeated.
4443 We can test for values between ESC_b and ESC_Z for the latter; this may
4444 have to change if any new ones are ever created. */
4445
4446 case '\\':
4447 tempptr = ptr;
4448 c = check_escape(&ptr, errorcodeptr, cd->bracount, options, FALSE);
4449 if (*errorcodeptr != 0) goto FAILED;
4450
4451 if (c < 0)
4452 {
4453 if (-c == ESC_Q) /* Handle start of quoted string */
4454 {
4455 if (ptr[1] == '\\' && ptr[2] == 'E') ptr += 2; /* avoid empty string */
4456 else inescq = TRUE;
4457 continue;
4458 }
4459
4460 if (-c == ESC_E) continue; /* Perl ignores an orphan \E */
4461
4462 /* For metasequences that actually match a character, we disable the
4463 setting of a first character if it hasn't already been set. */
4464
4465 if (firstbyte == REQ_UNSET && -c > ESC_b && -c < ESC_Z)
4466 firstbyte = REQ_NONE;
4467
4468 /* Set values to reset to if this is followed by a zero repeat. */
4469
4470 zerofirstbyte = firstbyte;
4471 zeroreqbyte = reqbyte;
4472
4473 /* \k<name> or \k'name' is a back reference by name (Perl syntax) */
4474
4475 if (-c == ESC_k && (ptr[1] == '<' || ptr[1] == '\''))
4476 {
4477 is_recurse = FALSE;
4478 terminator = (*(++ptr) == '<')? '>' : '\'';
4479 goto NAMED_REF_OR_RECURSE;
4480 }
4481
4482 /* Back references are handled specially; must disable firstbyte if
4483 not set to cope with cases like (?=(\w+))\1: which would otherwise set
4484 ':' later. */
4485
4486 if (-c >= ESC_REF)
4487 {
4488 recno = -c - ESC_REF;
4489
4490 HANDLE_REFERENCE: /* Come here from named backref handling */
4491 if (firstbyte == REQ_UNSET) firstbyte = REQ_NONE;
4492 previous = code;
4493 *code++ = OP_REF;
4494 PUT2INC(code, 0, recno);
4495 cd->backref_map |= (recno < 32)? (1 << recno) : 1;
4496 if (recno > cd->top_backref) cd->top_backref = recno;
4497 }
4498
4499 /* So are Unicode property matches, if supported. */
4500
4501 #ifdef SUPPORT_UCP
4502 else if (-c == ESC_P || -c == ESC_p)
4503 {
4504 BOOL negated;
4505 int pdata;
4506 int ptype = get_ucp(&ptr, &negated, &pdata, errorcodeptr);
4507 if (ptype < 0) goto FAILED;
4508 previous = code;
4509 *code++ = ((-c == ESC_p) != negated)? OP_PROP : OP_NOTPROP;
4510 *code++ = ptype;
4511 *code++ = pdata;
4512 }
4513 #else
4514
4515 /* If Unicode properties are not supported, \X, \P, and \p are not
4516 allowed. */
4517
4518 else if (-c == ESC_X || -c == ESC_P || -c == ESC_p)
4519 {
4520 *errorcodeptr = ERR45;
4521 goto FAILED;
4522 }
4523 #endif
4524
4525 /* For the rest (including \X when Unicode properties are supported), we
4526 can obtain the OP value by negating the escape value. */
4527
4528 else
4529 {
4530 previous = (-c > ESC_b && -c < ESC_Z)? code : NULL;
4531 *code++ = -c;
4532 }
4533 continue;
4534 }
4535
4536 /* We have a data character whose value is in c. In UTF-8 mode it may have
4537 a value > 127. We set its representation in the length/buffer, and then
4538 handle it as a data character. */
4539
4540 #ifdef SUPPORT_UTF8
4541 if (utf8 && c > 127)
4542 mclength = _pcre_ord2utf8(c, mcbuffer);
4543 else
4544 #endif
4545
4546 {
4547 mcbuffer[0] = c;
4548 mclength = 1;
4549 }
4550 goto ONE_CHAR;
4551
4552
4553 /* ===================================================================*/
4554 /* Handle a literal character. It is guaranteed not to be whitespace or #
4555 when the extended flag is set. If we are in UTF-8 mode, it may be a
4556 multi-byte literal character. */
4557
4558 default:
4559 NORMAL_CHAR:
4560 mclength = 1;
4561 mcbuffer[0] = c;
4562
4563 #ifdef SUPPORT_UTF8
4564 if (utf8 && c >= 0xc0)
4565 {
4566 while ((ptr[1] & 0xc0) == 0x80)
4567 mcbuffer[mclength++] = *(++ptr);
4568 }
4569 #endif
4570
4571 /* At this point we have the character's bytes in mcbuffer, and the length
4572 in mclength. When not in UTF-8 mode, the length is always 1. */
4573
4574 ONE_CHAR:
4575 previous = code;
4576 *code++ = ((options & PCRE_CASELESS) != 0)? OP_CHARNC : OP_CHAR;
4577 for (c = 0; c < mclength; c++) *code++ = mcbuffer[c];
4578
4579 /* Set the first and required bytes appropriately. If no previous first
4580 byte, set it from this character, but revert to none on a zero repeat.
4581 Otherwise, leave the firstbyte value alone, and don't change it on a zero
4582 repeat. */
4583
4584 if (firstbyte == REQ_UNSET)
4585 {
4586 zerofirstbyte = REQ_NONE;
4587 zeroreqbyte = reqbyte;
4588
4589 /* If the character is more than one byte long, we can set firstbyte
4590 only if it is not to be matched caselessly. */
4591
4592 if (mclength == 1 || req_caseopt == 0)
4593 {
4594 firstbyte = mcbuffer[0] | req_caseopt;
4595 if (mclength != 1) reqbyte = code[-1] | cd->req_varyopt;
4596 }
4597 else firstbyte = reqbyte = REQ_NONE;
4598 }
4599
4600 /* firstbyte was previously set; we can set reqbyte only the length is
4601 1 or the matching is caseful. */
4602
4603 else
4604 {
4605 zerofirstbyte = firstbyte;
4606 zeroreqbyte = reqbyte;
4607 if (mclength == 1 || req_caseopt == 0)
4608 reqbyte = code[-1] | req_caseopt | cd->req_varyopt;
4609 }
4610
4611 break; /* End of literal character handling */
4612 }
4613 } /* end of big loop */
4614
4615
4616 /* Control never reaches here by falling through, only by a goto for all the
4617 error states. Pass back the position in the pattern so that it can be displayed
4618 to the user for diagnosing the error. */
4619
4620 FAILED:
4621 *ptrptr = ptr;
4622 return FALSE;
4623 }
4624
4625
4626
4627
4628 /*************************************************
4629 * Compile sequence of alternatives *
4630 *************************************************/
4631
4632 /* On entry, ptr is pointing past the bracket character, but on return it
4633 points to the closing bracket, or vertical bar, or end of string. The code
4634 variable is pointing at the byte into which the BRA operator has been stored.
4635 If the ims options are changed at the start (for a (?ims: group) or during any
4636 branch, we need to insert an OP_OPT item at the start of every following branch
4637 to ensure they get set correctly at run time, and also pass the new options
4638 into every subsequent branch compile.
4639
4640 This function is used during the pre-compile phase when we are trying to find
4641 out the amount of memory needed, as well as during the real compile phase. The
4642 value of lengthptr distinguishes the two phases.
4643
4644 Argument:
4645 options option bits, including any changes for this subpattern
4646 oldims previous settings of ims option bits
4647 codeptr -> the address of the current code pointer
4648 ptrptr -> the address of the current pattern pointer
4649 errorcodeptr -> pointer to error code variable
4650 lookbehind TRUE if this is a lookbehind assertion
4651 skipbytes skip this many bytes at start (for brackets and OP_COND)
4652 firstbyteptr place to put the first required character, or a negative number
4653 reqbyteptr place to put the last required character, or a negative number
4654 bcptr pointer to the chain of currently open branches
4655 cd points to the data block with tables pointers etc.
4656 lengthptr NULL during the real compile phase
4657 points to length accumulator during pre-compile phase
4658
4659 Returns: TRUE on success
4660 */
4661
4662 static BOOL
4663 compile_regex(int options, int oldims, uschar **codeptr, const uschar **ptrptr,
4664 int *errorcodeptr, BOOL lookbehind, int skipbytes, int *firstbyteptr,
4665 int *reqbyteptr, branch_chain *bcptr, compile_data *cd, int *lengthptr)
4666 {
4667 const uschar *ptr = *ptrptr;
4668 uschar *code = *codeptr;
4669 uschar *last_branch = code;
4670 uschar *start_bracket = code;
4671 uschar *reverse_count = NULL;
4672 int firstbyte, reqbyte;
4673 int branchfirstbyte, branchreqbyte;
4674 int length;
4675 branch_chain bc;
4676
4677 bc.outer = bcptr;
4678 bc.current = code;
4679
4680 firstbyte = reqbyte = REQ_UNSET;
4681
4682 /* Accumulate the length for use in the pre-compile phase. Start with the
4683 length of the BRA and KET and any extra bytes that are required at the
4684 beginning. We accumulate in a local variable to save frequent testing of
4685 lenthptr for NULL. We cannot do this by looking at the value of code at the
4686 start and end of each alternative, because compiled items are discarded during
4687 the pre-compile phase so that the work space is not exceeded. */
4688
4689 length = 2 + 2*LINK_SIZE + skipbytes;
4690
4691 /* WARNING: If the above line is changed for any reason, you must also change
4692 the code that abstracts option settings at the start of the pattern and makes
4693 them global. It tests the value of length for (2 + 2*LINK_SIZE) in the
4694 pre-compile phase to find out whether anything has yet been compiled or not. */
4695
4696 /* Offset is set zero to mark that this bracket is still open */
4697
4698 PUT(code, 1, 0);
4699 code += 1 + LINK_SIZE + skipbytes;
4700
4701 /* Loop for each alternative branch */
4702
4703 for (;;)
4704 {
4705 /* Handle a change of ims options at the start of the branch */
4706
4707 if ((options & PCRE_IMS) != oldims)
4708 {
4709 *code++ = OP_OPT;
4710 *code++ = options & PCRE_IMS;
4711 length += 2;
4712 }
4713
4714 /* Set up dummy OP_REVERSE if lookbehind assertion */
4715
4716 if (lookbehind)
4717 {
4718 *code++ = OP_REVERSE;
4719 reverse_count = code;
4720 PUTINC(code, 0, 0);
4721 length += 1 + LINK_SIZE;
4722 }
4723
4724 /* Now compile the branch; in the pre-compile phase its length gets added
4725 into the length. */
4726
4727 if (!compile_branch(&options, &code, &ptr, errorcodeptr, &branchfirstbyte,
4728 &branchreqbyte, &bc, cd, (lengthptr == NULL)? NULL : &length))
4729 {
4730 *ptrptr = ptr;
4731 return FALSE;
4732 }
4733
4734 /* In the real compile phase, there is some post-processing to be done. */
4735
4736 if (lengthptr == NULL)
4737 {
4738 /* If this is the first branch, the firstbyte and reqbyte values for the
4739 branch become the values for the regex. */
4740
4741 if (*last_branch != OP_ALT)
4742 {
4743 firstbyte = branchfirstbyte;
4744 reqbyte = branchreqbyte;
4745 }
4746
4747 /* If this is not the first branch, the first char and reqbyte have to
4748 match the values from all the previous branches, except that if the
4749 previous value for reqbyte didn't have REQ_VARY set, it can still match,
4750 and we set REQ_VARY for the regex. */
4751
4752 else
4753 {
4754 /* If we previously had a firstbyte, but it doesn't match the new branch,
4755 we have to abandon the firstbyte for the regex, but if there was
4756 previously no reqbyte, it takes on the value of the old firstbyte. */
4757
4758 if (firstbyte >= 0 && firstbyte != branchfirstbyte)
4759 {
4760 if (reqbyte < 0) reqbyte = firstbyte;
4761 firstbyte = REQ_NONE;
4762 }
4763
4764 /* If we (now or from before) have no firstbyte, a firstbyte from the
4765 branch becomes a reqbyte if there isn't a branch reqbyte. */
4766
4767 if (firstbyte < 0 && branchfirstbyte >= 0 && branchreqbyte < 0)
4768 branchreqbyte = branchfirstbyte;
4769
4770 /* Now ensure that the reqbytes match */
4771
4772 if ((reqbyte & ~REQ_VARY) != (branchreqbyte & ~REQ_VARY))
4773 reqbyte = REQ_NONE;
4774 else reqbyte |= branchreqbyte; /* To "or" REQ_VARY */
4775 }
4776
4777 /* If lookbehind, check that this branch matches a fixed-length string, and
4778 put the length into the OP_REVERSE item. Temporarily mark the end of the
4779 branch with OP_END. */
4780
4781 if (lookbehind)
4782 {
4783 int fixed_length;
4784 *code = OP_END;
4785 fixed_length = find_fixedlength(last_branch, options);
4786 DPRINTF(("fixed length = %d\n", fixed_length));
4787 if (fixed_length < 0)
4788 {
4789 *errorcodeptr = (fixed_length == -2)? ERR36 : ERR25;
4790 *ptrptr = ptr;
4791 return FALSE;
4792 }
4793 PUT(reverse_count, 0, fixed_length);
4794 }
4795 }
4796
4797 /* Reached end of expression, either ')' or end of pattern. Go back through
4798 the alternative branches and reverse the chain of offsets, with the field in
4799 the BRA item now becoming an offset to the first alternative. If there are
4800 no alternatives, it points to the end of the group. The length in the
4801 terminating ket is always the length of the whole bracketed item. If any of
4802 the ims options were changed inside the group, compile a resetting op-code
4803 following, except at the very end of the pattern. Return leaving the pointer
4804 at the terminating char. */
4805
4806 if (*ptr != '|')
4807 {
4808 int branch_length = code - last_branch;
4809 do
4810 {
4811 int prev_length = GET(last_branch, 1);
4812 PUT(last_branch, 1, branch_length);
4813 branch_length = prev_length;
4814 last_branch -= branch_length;
4815 }
4816 while (branch_length > 0);
4817
4818 /* Fill in the ket */
4819
4820 *code = OP_KET;
4821 PUT(code, 1, code - start_bracket);
4822 code += 1 + LINK_SIZE;
4823
4824 /* Resetting option if needed */
4825
4826 if ((options & PCRE_IMS) != oldims && *ptr == ')')
4827 {
4828 *code++ = OP_OPT;
4829 *code++ = oldims;
4830 length += 2;
4831 }
4832
4833 /* Set values to pass back */
4834
4835 *codeptr = code;
4836 *ptrptr = ptr;
4837 *firstbyteptr = firstbyte;
4838 *reqbyteptr = reqbyte;
4839 if (lengthptr != NULL) *lengthptr += length;
4840 return TRUE;
4841 }
4842
4843 /* Another branch follows; insert an "or" node. Its length field points back
4844 to the previous branch while the bracket remains open. At the end the chain
4845 is reversed. It's done like this so that the start of the bracket has a
4846 zero offset until it is closed, making it possible to detect recursion. */
4847
4848 *code = OP_ALT;
4849 PUT(code, 1, code - last_branch);
4850 bc.current = last_branch = code;
4851 code += 1 + LINK_SIZE;
4852 ptr++;
4853 length += 1 + LINK_SIZE;
4854 }
4855 /* Control never reaches here */
4856 }
4857
4858
4859
4860
4861 /*************************************************
4862 * Check for anchored expression *
4863 *************************************************/
4864
4865 /* Try to find out if this is an anchored regular expression. Consider each
4866 alternative branch. If they all start with OP_SOD or OP_CIRC, or with a bracket
4867 all of whose alternatives start with OP_SOD or OP_CIRC (recurse ad lib), then
4868 it's anchored. However, if this is a multiline pattern, then only OP_SOD
4869 counts, since OP_CIRC can match in the middle.
4870
4871 We can also consider a regex to be anchored if OP_SOM starts all its branches.
4872 This is the code for \G, which means "match at start of match position, taking
4873 into account the match offset".
4874
4875 A branch is also implicitly anchored if it starts with .* and DOTALL is set,
4876 because that will try the rest of the pattern at all possible matching points,
4877 so there is no point trying again.... er ....
4878
4879 .... except when the .* appears inside capturing parentheses, and there is a
4880 subsequent back reference to those parentheses. We haven't enough information
4881 to catch that case precisely.
4882
4883 At first, the best we could do was to detect when .* was in capturing brackets
4884 and the highest back reference was greater than or equal to that level.
4885 However, by keeping a bitmap of the first 31 back references, we can catch some
4886 of the more common cases more precisely.
4887
4888 Arguments:
4889 code points to start of expression (the bracket)
4890 options points to the options setting
4891 bracket_map a bitmap of which brackets we are inside while testing; this
4892 handles up to substring 31; after that we just have to take
4893 the less precise approach
4894 backref_map the back reference bitmap
4895
4896 Returns: TRUE or FALSE
4897 */
4898
4899 static BOOL
4900 is_anchored(register const uschar *code, int *options, unsigned int bracket_map,
4901 unsigned int backref_map)
4902 {
4903 do {
4904 const uschar *scode = first_significant_code(code + _pcre_OP_lengths[*code],
4905 options, PCRE_MULTILINE, FALSE);
4906 register int op = *scode;
4907
4908 /* Non-capturing brackets */
4909
4910 if (op == OP_BRA)
4911 {
4912 if (!is_anchored(scode, options, bracket_map, backref_map)) return FALSE;
4913 }
4914
4915 /* Capturing brackets */
4916
4917 else if (op == OP_CBRA)
4918 {
4919 int n = GET2(scode, 1+LINK_SIZE);
4920 int new_map = bracket_map | ((n < 32)? (1 << n) : 1);
4921 if (!is_anchored(scode, options, new_map, backref_map)) return FALSE;
4922 }
4923
4924 /* Other brackets */
4925
4926 else if (op == OP_ASSERT || op == OP_ONCE || op == OP_COND)
4927 {
4928 if (!is_anchored(scode, options, bracket_map, backref_map)) return FALSE;
4929 }
4930
4931 /* .* is not anchored unless DOTALL is set and it isn't in brackets that
4932 are or may be referenced. */
4933
4934 else if ((op == OP_TYPESTAR || op == OP_TYPEMINSTAR ||
4935 op == OP_TYPEPOSSTAR) &&
4936 (*options & PCRE_DOTALL) != 0)
4937 {
4938 if (scode[1] != OP_ANY || (bracket_map & backref_map) != 0) return FALSE;
4939 }
4940
4941 /* Check for explicit anchoring */
4942
4943 else if (op != OP_SOD && op != OP_SOM &&
4944 ((*options & PCRE_MULTILINE) != 0 || op != OP_CIRC))
4945 return FALSE;
4946 code += GET(code, 1);
4947 }
4948 while (*code == OP_ALT); /* Loop for each alternative */
4949 return TRUE;
4950 }
4951
4952
4953
4954 /*************************************************
4955 * Check for starting with ^ or .* *
4956 *************************************************/
4957
4958 /* This is called to find out if every branch starts with ^ or .* so that
4959 "first char" processing can be done to speed things up in multiline
4960 matching and for non-DOTALL patterns that start with .* (which must start at
4961 the beginning or after \n). As in the case of is_anchored() (see above), we
4962 have to take account of back references to capturing brackets that contain .*
4963 because in that case we can't make the assumption.
4964
4965 Arguments:
4966 code points to start of expression (the bracket)
4967 bracket_map a bitmap of which brackets we are inside while testing; this
4968 handles up to substring 31; after that we just have to take
4969 the less precise approach
4970 backref_map the back reference bitmap
4971
4972 Returns: TRUE or FALSE
4973 */
4974
4975 static BOOL
4976 is_startline(const uschar *code, unsigned int bracket_map,
4977 unsigned int backref_map)
4978 {
4979 do {
4980 const uschar *scode = first_significant_code(code + _pcre_OP_lengths[*code],
4981 NULL, 0, FALSE);
4982 register int op = *scode;
4983
4984 /* Non-capturing brackets */
4985
4986 if (op == OP_BRA)
4987 {
4988 if (!is_startline(scode, bracket_map, backref_map)) return FALSE;
4989 }
4990
4991 /* Capturing brackets */
4992
4993 else if (op == OP_CBRA)
4994 {
4995 int n = GET2(scode, 1+LINK_SIZE);
4996 int new_map = bracket_map | ((n < 32)? (1 << n) : 1);
4997 if (!is_startline(scode, new_map, backref_map)) return FALSE;
4998 }
4999
5000 /* Other brackets */
5001
5002 else if (op == OP_ASSERT || op == OP_ONCE || op == OP_COND)
5003 { if (!is_startline(scode, bracket_map, backref_map)) return FALSE; }
5004
5005 /* .* means "start at start or after \n" if it isn't in brackets that
5006 may be referenced. */
5007
5008 else if (op == OP_TYPESTAR || op == OP_TYPEMINSTAR || op == OP_TYPEPOSSTAR)
5009 {
5010 if (scode[1] != OP_ANY || (bracket_map & backref_map) != 0) return FALSE;
5011 }
5012
5013 /* Check for explicit circumflex */
5014
5015 else if (op != OP_CIRC) return FALSE;
5016
5017 /* Move on to the next alternative */
5018
5019 code += GET(code, 1);
5020 }
5021 while (*code == OP_ALT); /* Loop for each alternative */
5022 return TRUE;
5023 }
5024
5025
5026
5027 /*************************************************
5028 * Check for asserted fixed first char *
5029 *************************************************/
5030
5031 /* During compilation, the "first char" settings from forward assertions are
5032 discarded, because they can cause conflicts with actual literals that follow.
5033 However, if we end up without a first char setting for an unanchored pattern,
5034 it is worth scanning the regex to see if there is an initial asserted first
5035 char. If all branches start with the same asserted char, or with a bracket all
5036 of whose alternatives start with the same asserted char (recurse ad lib), then
5037 we return that char, otherwise -1.
5038
5039 Arguments:
5040 code points to start of expression (the bracket)
5041 options pointer to the options (used to check casing changes)
5042 inassert TRUE if in an assertion
5043
5044 Returns: -1 or the fixed first char
5045 */
5046
5047 static int
5048 find_firstassertedchar(const uschar *code, int *options, BOOL inassert)
5049 {
5050 register int c = -1;
5051 do {
5052 int d;
5053 const uschar *scode =
5054 first_significant_code(code + 1+LINK_SIZE, options, PCRE_CASELESS, TRUE);
5055 register int op = *scode;
5056
5057 switch(op)
5058 {
5059 default:
5060 return -1;
5061
5062 case OP_BRA:
5063 case OP_CBRA:
5064 case OP_ASSERT:
5065 case OP_ONCE:
5066 case OP_COND:
5067 if ((d = find_firstassertedchar(scode, options, op == OP_ASSERT)) < 0)
5068 return -1;
5069 if (c < 0) c = d; else if (c != d) return -1;
5070 break;
5071
5072 case OP_EXACT: /* Fall through */
5073 scode += 2;
5074
5075 case OP_CHAR:
5076 case OP_CHARNC:
5077 case OP_PLUS:
5078 case OP_MINPLUS:
5079 case OP_POSPLUS:
5080 if (!inassert) return -1;
5081 if (c < 0)
5082 {
5083 c = scode[1];
5084 if ((*options & PCRE_CASELESS) != 0) c |= REQ_CASELESS;
5085 }
5086 else if (c != scode[1]) return -1;
5087 break;
5088 }
5089
5090 code += GET(code, 1);
5091 }
5092 while (*code == OP_ALT);
5093 return c;
5094 }
5095
5096
5097
5098 /*************************************************
5099 * Compile a Regular Expression *
5100 *************************************************/
5101
5102 /* This function takes a string and returns a pointer to a block of store
5103 holding a compiled version of the expression. The original API for this
5104 function had no error code return variable; it is retained for backwards
5105 compatibility. The new function is given a new name.
5106
5107 Arguments:
5108 pattern the regular expression
5109 options various option bits
5110 errorcodeptr pointer to error code variable (pcre_compile2() only)
5111 can be NULL if you don't want a code value
5112 errorptr pointer to pointer to error text
5113 erroroffset ptr offset in pattern where error was detected
5114 tables pointer to character tables or NULL
5115
5116 Returns: pointer to compiled data block, or NULL on error,
5117 with errorptr and erroroffset set
5118 */
5119
5120 PCRE_EXP_DEFN pcre *
5121 pcre_compile(const char *pattern, int options, const char **errorptr,
5122 int *erroroffset, const unsigned char *tables)
5123 {
5124 return pcre_compile2(pattern, options, NULL, errorptr, erroroffset, tables);
5125 }
5126
5127
5128 PCRE_EXP_DEFN pcre *
5129 pcre_compile2(const char *pattern, int options, int *errorcodeptr,
5130 const char **errorptr, int *erroroffset, const unsigned char *tables)
5131 {
5132 real_pcre *re;
5133 int length = 1; /* For final END opcode */
5134 int firstbyte, reqbyte, newline;
5135 int errorcode = 0;
5136 #ifdef SUPPORT_UTF8
5137 BOOL utf8;
5138 #endif
5139 size_t size;
5140 uschar *code;
5141 const uschar *codestart;
5142 const uschar *ptr;
5143 compile_data compile_block;
5144 compile_data *cd = &compile_block;
5145
5146 /* This space is used for "compiling" into during the first phase, when we are
5147 computing the amount of memory that is needed. Compiled items are thrown away
5148 as soon as possible, so that a fairly large buffer should be sufficient for
5149 this purpose. The same space is used in the second phase for remembering where
5150 to fill in forward references to subpatterns. */
5151
5152 uschar cworkspace[COMPILE_WORK_SIZE];
5153
5154
5155 /* Set this early so that early errors get offset 0. */
5156
5157 ptr = (const uschar *)pattern;
5158
5159 /* We can't pass back an error message if errorptr is NULL; I guess the best we
5160 can do is just return NULL, but we can set a code value if there is a code
5161 pointer. */
5162
5163 if (errorptr == NULL)
5164 {
5165 if (errorcodeptr != NULL) *errorcodeptr = 99;
5166 return NULL;
5167 }
5168
5169 *errorptr = NULL;
5170 if (errorcodeptr != NULL) *errorcodeptr = ERR0;
5171
5172 /* However, we can give a message for this error */
5173
5174 if (erroroffset == NULL)
5175 {
5176 errorcode = ERR16;
5177 goto PCRE_EARLY_ERROR_RETURN2;
5178 }
5179
5180 *erroroffset = 0;
5181
5182 /* Can't support UTF8 unless PCRE has been compiled to include the code. */
5183
5184 #ifdef SUPPORT_UTF8
5185 utf8 = (options & PCRE_UTF8) != 0;
5186 if (utf8 && (options & PCRE_NO_UTF8_CHECK) == 0 &&
5187 (*erroroffset = _pcre_valid_utf8((uschar *)pattern, -1)) >= 0)
5188 {
5189 errorcode = ERR44;
5190 goto PCRE_EARLY_ERROR_RETURN2;
5191 }
5192 #else
5193 if ((options & PCRE_UTF8) != 0)
5194 {
5195 errorcode = ERR32;
5196 goto PCRE_EARLY_ERROR_RETURN;
5197 }
5198 #endif
5199
5200 if ((options & ~PUBLIC_OPTIONS) != 0)
5201 {
5202 errorcode = ERR17;
5203 goto PCRE_EARLY_ERROR_RETURN;
5204 }
5205
5206 /* Set up pointers to the individual character tables */
5207
5208 if (tables == NULL) tables = _pcre_default_tables;
5209 cd->lcc = tables + lcc_offset;
5210 cd->fcc = tables + fcc_offset;
5211 cd->cbits = tables + cbits_offset;
5212 cd->ctypes = tables + ctypes_offset;
5213
5214 /* Handle different types of newline. The three bits give seven cases. The
5215 current code allows for fixed one- or two-byte sequences, plus "any" and
5216 "anycrlf". */
5217
5218 switch (options & (PCRE_NEWLINE_CRLF | PCRE_NEWLINE_ANY))
5219 {
5220 case 0: newline = NEWLINE; break; /* Compile-time default */
5221 case PCRE_NEWLINE_CR: newline = '\r'; break;
5222 case PCRE_NEWLINE_LF: newline = '\n'; break;
5223 case PCRE_NEWLINE_CR+
5224 PCRE_NEWLINE_LF: newline = ('\r' << 8) | '\n'; break;
5225 case PCRE_NEWLINE_ANY: newline = -1; break;
5226 case PCRE_NEWLINE_ANYCRLF: newline = -2; break;
5227 default: errorcode = ERR56; goto PCRE_EARLY_ERROR_RETURN;
5228 }
5229
5230 if (newline == -2)
5231 {
5232 cd->nltype = NLTYPE_ANYCRLF;
5233 }
5234 else if (newline < 0)
5235 {
5236 cd->nltype = NLTYPE_ANY;
5237 }
5238 else
5239 {
5240 cd->nltype = NLTYPE_FIXED;
5241 if (newline > 255)
5242 {
5243 cd->nllen = 2;
5244 cd->nl[0] = (newline >> 8) & 255;
5245 cd->nl[1] = newline & 255;
5246 }
5247 else
5248 {
5249 cd->nllen = 1;
5250 cd->nl[0] = newline;
5251 }
5252 }
5253
5254 /* Maximum back reference and backref bitmap. The bitmap records up to 31 back
5255 references to help in deciding whether (.*) can be treated as anchored or not.
5256 */
5257
5258 cd->top_backref = 0;
5259 cd->backref_map = 0;
5260
5261 /* Reflect pattern for debugging output */
5262
5263 DPRINTF(("------------------------------------------------------------------\n"));
5264 DPRINTF(("%s\n", pattern));
5265
5266 /* Pretend to compile the pattern while actually just accumulating the length
5267 of memory required. This behaviour is triggered by passing a non-NULL final
5268 argument to compile_regex(). We pass a block of workspace (cworkspace) for it
5269 to compile parts of the pattern into; the compiled code is discarded when it is
5270 no longer needed, so hopefully this workspace will never overflow, though there
5271 is a test for its doing so. */
5272
5273 cd->bracount = 0;
5274 cd->names_found = 0;
5275 cd->name_entry_size = 0;
5276 cd->name_table = NULL;
5277 cd->start_workspace = cworkspace;
5278 cd->start_code = cworkspace;
5279 cd->hwm = cworkspace;
5280 cd->start_pattern = (const uschar *)pattern;
5281 cd->end_pattern = (const uschar *)(pattern + strlen(pattern));
5282 cd->req_varyopt = 0;
5283 cd->nopartial = FALSE;
5284 cd->external_options = options;
5285
5286 /* Now do the pre-compile. On error, errorcode will be set non-zero, so we
5287 don't need to look at the result of the function here. The initial options have
5288 been put into the cd block so that they can be changed if an option setting is
5289 found within the regex right at the beginning. Bringing initial option settings
5290 outside can help speed up starting point checks. */
5291
5292 code = cworkspace;
5293 *code = OP_BRA;
5294 (void)compile_regex(cd->external_options, cd->external_options & PCRE_IMS,
5295 &code, &ptr, &errorcode, FALSE, 0, &firstbyte, &reqbyte, NULL, cd, &length);
5296 if (errorcode != 0) goto PCRE_EARLY_ERROR_RETURN;
5297
5298 DPRINTF(("end pre-compile: length=%d workspace=%d\n", length,
5299 cd->hwm - cworkspace));
5300
5301 if (length > MAX_PATTERN_SIZE)
5302 {
5303 errorcode = ERR20;
5304 goto PCRE_EARLY_ERROR_RETURN;
5305 }
5306
5307 /* Compute the size of data block needed and get it, either from malloc or
5308 externally provided function. Integer overflow should no longer be possible
5309 because nowadays we limit the maximum value of cd->names_found and
5310 cd->name_entry_size. */
5311
5312 size = length + sizeof(real_pcre) + cd->names_found * (cd->name_entry_size + 3);
5313 re = (real_pcre *)(pcre_malloc)(size);
5314
5315 if (re == NULL)
5316 {
5317 errorcode = ERR21;
5318 goto PCRE_EARLY_ERROR_RETURN;
5319 }
5320
5321 /* Put in the magic number, and save the sizes, initial options, and character
5322 table pointer. NULL is used for the default character tables. The nullpad field
5323 is at the end; it's there to help in the case when a regex compiled on a system
5324 with 4-byte pointers is run on another with 8-byte pointers. */
5325
5326 re->magic_number = MAGIC_NUMBER;
5327 re->size = size;
5328 re->options = cd->external_options;
5329 re->dummy1 = 0;
5330 re->first_byte = 0;
5331 re->req_byte = 0;
5332 re->name_table_offset = sizeof(real_pcre);
5333 re->name_entry_size = cd->name_entry_size;
5334 re->name_count = cd->names_found;
5335 re->ref_count = 0;
5336 re->tables = (tables == _pcre_default_tables)? NULL : tables;
5337 re->nullpad = NULL;
5338
5339 /* The starting points of the name/number translation table and of the code are
5340 passed around in the compile data block. The start/end pattern and initial
5341 options are already set from the pre-compile phase, as is the name_entry_size
5342 field. Reset the bracket count and the names_found field. Also reset the hwm
5343 field; this time it's used for remembering forward references to subpatterns.
5344 */
5345
5346 cd->bracount = 0;
5347 cd->names_found = 0;
5348 cd->name_table = (uschar *)re + re->name_table_offset;
5349 codestart = cd->name_table + re->name_entry_size * re->name_count;
5350 cd->start_code = codestart;
5351 cd->hwm = cworkspace;
5352 cd->req_varyopt = 0;
5353 cd->nopartial = FALSE;
5354
5355 /* Set up a starting, non-extracting bracket, then compile the expression. On
5356 error, errorcode will be set non-zero, so we don't need to look at the result
5357 of the function here. */
5358
5359 ptr = (const uschar *)pattern;
5360 code = (uschar *)codestart;
5361 *code = OP_BRA;
5362 (void)compile_regex(re->options, re->options & PCRE_IMS, &code, &ptr,
5363 &errorcode, FALSE, 0, &firstbyte, &reqbyte, NULL, cd, NULL);
5364 re->top_bracket = cd->bracount;
5365 re->top_backref = cd->top_backref;
5366
5367 if (cd->nopartial) re->options |= PCRE_NOPARTIAL;
5368
5369 /* If not reached end of pattern on success, there's an excess bracket. */
5370
5371 if (errorcode == 0 && *ptr != 0) errorcode = ERR22;
5372
5373 /* Fill in the terminating state and check for disastrous overflow, but
5374 if debugging, leave the test till after things are printed out. */
5375
5376 *code++ = OP_END;
5377
5378 #ifndef DEBUG
5379 if (code - codestart > length) errorcode = ERR23;
5380 #endif
5381
5382 /* Fill in any forward references that are required. */
5383
5384 while (errorcode == 0 && cd->hwm > cworkspace)
5385 {
5386 int offset, recno;
5387 const uschar *groupptr;
5388 cd->hwm -= LINK_SIZE;
5389 offset = GET(cd->hwm, 0);
5390 recno = GET(codestart, offset);
5391 groupptr = find_bracket(codestart, (re->options & PCRE_UTF8) != 0, recno);
5392 if (groupptr == NULL) errorcode = ERR53;
5393 else PUT(((uschar *)codestart), offset, groupptr - codestart);
5394 }
5395
5396 /* Give an error if there's back reference to a non-existent capturing
5397 subpattern. */
5398
5399 if (errorcode == 0 && re->top_backref > re->top_bracket) errorcode = ERR15;
5400
5401 /* Failed to compile, or error while post-processing */
5402
5403 if (errorcode != 0)
5404 {
5405 (pcre_free)(re);
5406 PCRE_EARLY_ERROR_RETURN:
5407 *erroroffset = ptr - (const uschar *)pattern;
5408 PCRE_EARLY_ERROR_RETURN2:
5409 *errorptr = error_texts[errorcode];
5410 if (errorcodeptr != NULL) *errorcodeptr = errorcode;
5411 return NULL;
5412 }
5413
5414 /* If the anchored option was not passed, set the flag if we can determine that
5415 the pattern is anchored by virtue of ^ characters or \A or anything else (such
5416 as starting with .* when DOTALL is set).
5417
5418 Otherwise, if we know what the first byte has to be, save it, because that
5419 speeds up unanchored matches no end. If not, see if we can set the
5420 PCRE_STARTLINE flag. This is helpful for multiline matches when all branches
5421 start with ^. and also when all branches start with .* for non-DOTALL matches.
5422 */
5423
5424 if ((re->options & PCRE_ANCHORED) == 0)
5425 {
5426 int temp_options = re->options; /* May get changed during these scans */
5427 if (is_anchored(codestart, &temp_options, 0, cd->backref_map))
5428 re->options |= PCRE_ANCHORED;
5429 else
5430 {
5431 if (firstbyte < 0)
5432 firstbyte = find_firstassertedchar(codestart, &temp_options, FALSE);
5433 if (firstbyte >= 0) /* Remove caseless flag for non-caseable chars */
5434 {
5435 int ch = firstbyte & 255;
5436 re->first_byte = ((firstbyte & REQ_CASELESS) != 0 &&
5437 cd->fcc[ch] == ch)? ch : firstbyte;
5438 re->options |= PCRE_FIRSTSET;
5439 }
5440 else if (is_startline(codestart, 0, cd->backref_map))
5441 re->options |= PCRE_STARTLINE;
5442 }
5443 }
5444
5445 /* For an anchored pattern, we use the "required byte" only if it follows a
5446 variable length item in the regex. Remove the caseless flag for non-caseable
5447 bytes. */
5448
5449 if (reqbyte >= 0 &&
5450 ((re->options & PCRE_ANCHORED) == 0 || (reqbyte & REQ_VARY) != 0))
5451 {
5452 int ch = reqbyte & 255;
5453 re->req_byte = ((reqbyte & REQ_CASELESS) != 0 &&
5454 cd->fcc[ch] == ch)? (reqbyte & ~REQ_CASELESS) : reqbyte;
5455 re->options |= PCRE_REQCHSET;
5456 }
5457
5458 /* Print out the compiled data if debugging is enabled. This is never the
5459 case when building a production library. */
5460
5461 #ifdef DEBUG
5462
5463 printf("Length = %d top_bracket = %d top_backref = %d\n",
5464 length, re->top_bracket, re->top_backref);
5465
5466 if (re->options != 0)
5467 {
5468 printf("%s%s%s%s%s%s%s%s%s\n",
5469 ((re->options & PCRE_NOPARTIAL) != 0)? "nopartial " : "",
5470 ((re->options & PCRE_ANCHORED) != 0)? "anchored " : "",
5471 ((re->options & PCRE_CASELESS) != 0)? "caseless " : "",
5472 ((re->options & PCRE_EXTENDED) != 0)? "extended " : "",
5473 ((re->options & PCRE_MULTILINE) != 0)? "multiline " : "",
5474 ((re->options & PCRE_DOTALL) != 0)? "dotall " : "",
5475 ((re->options & PCRE_DOLLAR_ENDONLY) != 0)? "endonly " : "",
5476 ((re->options & PCRE_EXTRA) != 0)? "extra " : "",
5477 ((re->options & PCRE_UNGREEDY) != 0)? "ungreedy " : "");
5478 }
5479
5480 if ((re->options & PCRE_FIRSTSET) != 0)
5481 {
5482 int ch = re->first_byte & 255;
5483 const char *caseless = ((re->first_byte & REQ_CASELESS) == 0)?
5484 "" : " (caseless)";
5485 if (isprint(ch)) printf("First char = %c%s\n", ch, caseless);
5486 else printf("First char = \\x%02x%s\n", ch, caseless);
5487 }
5488
5489 if ((re->options & PCRE_REQCHSET) != 0)
5490 {
5491 int ch = re->req_byte & 255;
5492 const char *caseless = ((re->req_byte & REQ_CASELESS) == 0)?
5493 "" : " (caseless)";
5494 if (isprint(ch)) printf("Req char = %c%s\n", ch, caseless);
5495 else printf("Req char = \\x%02x%s\n", ch, caseless);
5496 }
5497
5498 pcre_printint(re, stdout, TRUE);
5499
5500 /* This check is done here in the debugging case so that the code that
5501 was compiled can be seen. */
5502
5503 if (code - codestart > length)
5504 {
5505 (pcre_free)(re);
5506 *errorptr = error_texts[ERR23];
5507 *erroroffset = ptr - (uschar *)pattern;
5508 if (errorcodeptr != NULL) *errorcodeptr = ERR23;
5509 return NULL;
5510 }
5511 #endif /* DEBUG */
5512
5513 return (pcre *)re;
5514 }
5515
5516 /* End of pcre_compile.c */

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