| 60 |
*************************************************/ |
*************************************************/ |
| 61 |
|
|
| 62 |
/* Scan a parenthesized group and compute the minimum length of subject that |
/* Scan a parenthesized group and compute the minimum length of subject that |
| 63 |
is needed to match it. This is a lower bound; it does not mean there is a |
is needed to match it. This is a lower bound; it does not mean there is a |
| 64 |
string of that length that matches. In UTF8 mode, the result is in characters |
string of that length that matches. In UTF8 mode, the result is in characters |
| 65 |
rather than bytes. |
rather than bytes. |
| 66 |
|
|
| 67 |
Arguments: |
Arguments: |
| 68 |
code pointer to start of group (the bracket) |
code pointer to start of group (the bracket) |
| 69 |
startcode pointer to start of the whole pattern |
startcode pointer to start of the whole pattern |
| 70 |
options the compiling options |
options the compiling options |
| 71 |
|
|
| 72 |
Returns: the minimum length |
Returns: the minimum length |
| 73 |
-1 if \C was encountered |
-1 if \C was encountered |
| 74 |
-2 internal error (missing capturing bracket) |
-2 internal error (missing capturing bracket) |
| 75 |
*/ |
*/ |
| 76 |
|
|
| 77 |
static int |
static int |
| 91 |
for (;;) |
for (;;) |
| 92 |
{ |
{ |
| 93 |
int d, min; |
int d, min; |
| 94 |
uschar *cs, *ce; |
uschar *cs, *ce; |
| 95 |
register int op = *cc; |
register int op = *cc; |
| 96 |
|
|
| 97 |
switch (op) |
switch (op) |
| 98 |
{ |
{ |
| 99 |
case OP_CBRA: |
case OP_CBRA: |
| 100 |
case OP_SCBRA: |
case OP_SCBRA: |
| 101 |
case OP_BRA: |
case OP_BRA: |
| 102 |
case OP_SBRA: |
case OP_SBRA: |
| 103 |
case OP_ONCE: |
case OP_ONCE: |
| 104 |
case OP_COND: |
case OP_COND: |
| 105 |
case OP_SCOND: |
case OP_SCOND: |
| 106 |
d = find_minlength(cc, startcode, options); |
d = find_minlength(cc, startcode, options); |
| 107 |
if (d < 0) return d; |
if (d < 0) return d; |
| 108 |
branchlength += d; |
branchlength += d; |
| 119 |
case OP_KETRMAX: |
case OP_KETRMAX: |
| 120 |
case OP_KETRMIN: |
case OP_KETRMIN: |
| 121 |
case OP_END: |
case OP_END: |
| 122 |
if (length < 0 || (!had_recurse && branchlength < length)) |
if (length < 0 || (!had_recurse && branchlength < length)) |
| 123 |
length = branchlength; |
length = branchlength; |
| 124 |
if (*cc != OP_ALT) return length; |
if (*cc != OP_ALT) return length; |
| 125 |
cc += 1 + LINK_SIZE; |
cc += 1 + LINK_SIZE; |
| 126 |
branchlength = 0; |
branchlength = 0; |
| 127 |
had_recurse = FALSE; |
had_recurse = FALSE; |
| 128 |
break; |
break; |
| 129 |
|
|
| 130 |
/* Skip over assertive subpatterns */ |
/* Skip over assertive subpatterns */ |
| 156 |
case OP_WORD_BOUNDARY: |
case OP_WORD_BOUNDARY: |
| 157 |
cc += _pcre_OP_lengths[*cc]; |
cc += _pcre_OP_lengths[*cc]; |
| 158 |
break; |
break; |
| 159 |
|
|
| 160 |
/* Skip over a subpattern that has a {0} or {0,x} quantifier */ |
/* Skip over a subpattern that has a {0} or {0,x} quantifier */ |
| 161 |
|
|
| 162 |
case OP_BRAZERO: |
case OP_BRAZERO: |
| 163 |
case OP_BRAMINZERO: |
case OP_BRAMINZERO: |
| 164 |
case OP_SKIPZERO: |
case OP_SKIPZERO: |
| 165 |
cc += _pcre_OP_lengths[*cc]; |
cc += _pcre_OP_lengths[*cc]; |
| 166 |
do cc += GET(cc, 1); while (*cc == OP_ALT); |
do cc += GET(cc, 1); while (*cc == OP_ALT); |
| 184 |
if (utf8 && cc[-1] >= 0xc0) cc += _pcre_utf8_table4[cc[-1] & 0x3f]; |
if (utf8 && cc[-1] >= 0xc0) cc += _pcre_utf8_table4[cc[-1] & 0x3f]; |
| 185 |
#endif |
#endif |
| 186 |
break; |
break; |
| 187 |
|
|
| 188 |
case OP_TYPEPLUS: |
case OP_TYPEPLUS: |
| 189 |
case OP_TYPEMINPLUS: |
case OP_TYPEMINPLUS: |
| 190 |
case OP_TYPEPOSPLUS: |
case OP_TYPEPOSPLUS: |
| 191 |
branchlength++; |
branchlength++; |
| 192 |
cc += (cc[1] == OP_PROP || cc[1] == OP_NOTPROP)? 4 : 2; |
cc += (cc[1] == OP_PROP || cc[1] == OP_NOTPROP)? 4 : 2; |
| 193 |
break; |
break; |
| 196 |
need to skip over a multibyte character in UTF8 mode. */ |
need to skip over a multibyte character in UTF8 mode. */ |
| 197 |
|
|
| 198 |
case OP_EXACT: |
case OP_EXACT: |
| 199 |
case OP_NOTEXACT: |
case OP_NOTEXACT: |
| 200 |
branchlength += GET2(cc,1); |
branchlength += GET2(cc,1); |
| 201 |
cc += 4; |
cc += 4; |
| 202 |
#ifdef SUPPORT_UTF8 |
#ifdef SUPPORT_UTF8 |
| 225 |
case OP_ANY: |
case OP_ANY: |
| 226 |
case OP_ALLANY: |
case OP_ALLANY: |
| 227 |
case OP_EXTUNI: |
case OP_EXTUNI: |
| 228 |
case OP_HSPACE: |
case OP_HSPACE: |
| 229 |
case OP_NOT_HSPACE: |
case OP_NOT_HSPACE: |
| 230 |
case OP_VSPACE: |
case OP_VSPACE: |
| 231 |
case OP_NOT_VSPACE: |
case OP_NOT_VSPACE: |
| 232 |
branchlength++; |
branchlength++; |
| 233 |
cc++; |
cc++; |
| 234 |
break; |
break; |
| 235 |
|
|
| 236 |
/* "Any newline" might match two characters */ |
/* "Any newline" might match two characters */ |
| 237 |
|
|
| 238 |
case OP_ANYNL: |
case OP_ANYNL: |
| 239 |
branchlength += 2; |
branchlength += 2; |
| 240 |
cc++; |
cc++; |
| 241 |
break; |
break; |
| 242 |
|
|
| 243 |
/* The single-byte matcher means we can't proceed in UTF-8 mode */ |
/* The single-byte matcher means we can't proceed in UTF-8 mode */ |
| 244 |
|
|
| 248 |
#endif |
#endif |
| 249 |
branchlength++; |
branchlength++; |
| 250 |
cc++; |
cc++; |
| 251 |
break; |
break; |
| 252 |
|
|
| 253 |
/* For repeated character types, we have to test for \p and \P, which have |
/* For repeated character types, we have to test for \p and \P, which have |
| 254 |
an extra two bytes of parameters. */ |
an extra two bytes of parameters. */ |
| 287 |
case OP_CRPLUS: |
case OP_CRPLUS: |
| 288 |
case OP_CRMINPLUS: |
case OP_CRMINPLUS: |
| 289 |
branchlength++; |
branchlength++; |
| 290 |
/* Fall through */ |
/* Fall through */ |
| 291 |
|
|
| 292 |
case OP_CRSTAR: |
case OP_CRSTAR: |
| 293 |
case OP_CRMINSTAR: |
case OP_CRMINSTAR: |
| 294 |
case OP_CRQUERY: |
case OP_CRQUERY: |
| 295 |
case OP_CRMINQUERY: |
case OP_CRMINQUERY: |
| 296 |
cc++; |
cc++; |
| 297 |
break; |
break; |
| 298 |
|
|
| 299 |
case OP_CRRANGE: |
case OP_CRRANGE: |
| 300 |
case OP_CRMINRANGE: |
case OP_CRMINRANGE: |
| 301 |
branchlength += GET2(cc,1); |
branchlength += GET2(cc,1); |
| 302 |
cc += 5; |
cc += 5; |
| 303 |
break; |
break; |
| 304 |
|
|
| 305 |
default: |
default: |
| 306 |
branchlength++; |
branchlength++; |
| 307 |
break; |
break; |
| 308 |
} |
} |
| 309 |
break; |
break; |
| 310 |
|
|
| 311 |
/* Backreferences and subroutine calls are treated in the same way: we find |
/* Backreferences and subroutine calls are treated in the same way: we find |
| 312 |
the minimum length for the subpattern. A recursion, however, causes an |
the minimum length for the subpattern. A recursion, however, causes an |
| 313 |
a flag to be set that causes the length of this branch to be ignored. The |
a flag to be set that causes the length of this branch to be ignored. The |
| 314 |
logic is that a recursion can only make sense if there is another |
logic is that a recursion can only make sense if there is another |
| 315 |
alternation that stops the recursing. That will provide the minimum length |
alternation that stops the recursing. That will provide the minimum length |
| 316 |
(when no recursion happens). A backreference within the group that it is |
(when no recursion happens). A backreference within the group that it is |
| 317 |
referencing behaves in the same way. */ |
referencing behaves in the same way. */ |
| 318 |
|
|
| 319 |
case OP_REF: |
case OP_REF: |
| 320 |
ce = cs = (uschar *)_pcre_find_bracket(startcode, utf8, GET2(cc, 1)); |
ce = cs = (uschar *)_pcre_find_bracket(startcode, utf8, GET2(cc, 1)); |
| 321 |
if (cs == NULL) return -2; |
if (cs == NULL) return -2; |
| 323 |
if (cc > cs && cc < ce) |
if (cc > cs && cc < ce) |
| 324 |
{ |
{ |
| 325 |
d = 0; |
d = 0; |
| 326 |
had_recurse = TRUE; |
had_recurse = TRUE; |
| 327 |
} |
} |
| 328 |
else d = find_minlength(cs, startcode, options); |
else d = find_minlength(cs, startcode, options); |
| 329 |
cc += 3; |
cc += 3; |
| 330 |
|
|
| 331 |
/* Handle repeated back references */ |
/* Handle repeated back references */ |
| 332 |
|
|
| 333 |
switch (*cc) |
switch (*cc) |
| 334 |
{ |
{ |
| 335 |
case OP_CRSTAR: |
case OP_CRSTAR: |
| 339 |
min = 0; |
min = 0; |
| 340 |
cc++; |
cc++; |
| 341 |
break; |
break; |
| 342 |
|
|
| 343 |
case OP_CRRANGE: |
case OP_CRRANGE: |
| 344 |
case OP_CRMINRANGE: |
case OP_CRMINRANGE: |
| 345 |
min = GET2(cc, 1); |
min = GET2(cc, 1); |
| 346 |
cc += 5; |
cc += 5; |
| 347 |
break; |
break; |
| 348 |
|
|
| 349 |
default: |
default: |
| 350 |
min = 1; |
min = 1; |
| 351 |
break; |
break; |
| 352 |
} |
} |
| 353 |
|
|
| 354 |
branchlength += min * d; |
branchlength += min * d; |
| 355 |
break; |
break; |
| 356 |
|
|
| 357 |
case OP_RECURSE: |
case OP_RECURSE: |
| 358 |
cs = ce = (uschar *)startcode + GET(cc, 1); |
cs = ce = (uschar *)startcode + GET(cc, 1); |
| 359 |
if (cs == NULL) return -2; |
if (cs == NULL) return -2; |
| 360 |
do ce += GET(ce, 1); while (*ce == OP_ALT); |
do ce += GET(ce, 1); while (*ce == OP_ALT); |
| 361 |
if (cc > cs && cc < ce) |
if (cc > cs && cc < ce) |
| 362 |
had_recurse = TRUE; |
had_recurse = TRUE; |
| 363 |
else |
else |
| 364 |
branchlength += find_minlength(cs, startcode, options); |
branchlength += find_minlength(cs, startcode, options); |
| 365 |
cc += 1 + LINK_SIZE; |
cc += 1 + LINK_SIZE; |
| 366 |
break; |
break; |
| 367 |
|
|
| 368 |
/* Anything else does not or need not match a character. We can get the |
/* Anything else does not or need not match a character. We can get the |
| 369 |
item's length from the table, but for those that can match zero occurrences |
item's length from the table, but for those that can match zero occurrences |
| 370 |
of a character, we must take special action for UTF-8 characters. */ |
of a character, we must take special action for UTF-8 characters. */ |
| 371 |
|
|
| 372 |
case OP_UPTO: |
case OP_UPTO: |
| 373 |
case OP_NOTUPTO: |
case OP_NOTUPTO: |
| 374 |
case OP_MINUPTO: |
case OP_MINUPTO: |
| 375 |
case OP_NOTMINUPTO: |
case OP_NOTMINUPTO: |
| 376 |
case OP_POSUPTO: |
case OP_POSUPTO: |
| 377 |
case OP_STAR: |
case OP_STAR: |
| 378 |
case OP_MINSTAR: |
case OP_MINSTAR: |
| 379 |
case OP_NOTMINSTAR: |
case OP_NOTMINSTAR: |
| 380 |
case OP_POSSTAR: |
case OP_POSSTAR: |
| 381 |
case OP_NOTPOSSTAR: |
case OP_NOTPOSSTAR: |
| 382 |
case OP_QUERY: |
case OP_QUERY: |
| 383 |
case OP_MINQUERY: |
case OP_MINQUERY: |
| 384 |
case OP_NOTMINQUERY: |
case OP_NOTMINQUERY: |
| 385 |
case OP_POSQUERY: |
case OP_POSQUERY: |
| 386 |
case OP_NOTPOSQUERY: |
case OP_NOTPOSQUERY: |
| 387 |
cc += _pcre_OP_lengths[op]; |
cc += _pcre_OP_lengths[op]; |
| 388 |
#ifdef SUPPORT_UTF8 |
#ifdef SUPPORT_UTF8 |
| 389 |
if (utf8 && cc[-1] >= 0xc0) cc += _pcre_utf8_table4[cc[-1] & 0x3f]; |
if (utf8 && cc[-1] >= 0xc0) cc += _pcre_utf8_table4[cc[-1] & 0x3f]; |
| 390 |
#endif |
#endif |
| 391 |
break; |
break; |
| 392 |
|
|
| 393 |
/* For the record, these are the opcodes that are matched by "default": |
/* For the record, these are the opcodes that are matched by "default": |
| 394 |
OP_ACCEPT, OP_CLOSE, OP_COMMIT, OP_FAIL, OP_PRUNE, OP_SET_SOM, OP_SKIP, |
OP_ACCEPT, OP_CLOSE, OP_COMMIT, OP_FAIL, OP_PRUNE, OP_SET_SOM, OP_SKIP, |
| 395 |
OP_THEN. */ |
OP_THEN. */ |
| 396 |
|
|
| 397 |
default: |
default: |
| 398 |
cc += _pcre_OP_lengths[op]; |
cc += _pcre_OP_lengths[op]; |
| 399 |
break; |
break; |
| 885 |
(re->name_count * re->name_entry_size); |
(re->name_count * re->name_entry_size); |
| 886 |
|
|
| 887 |
/* For an anchored pattern, or an unanchored pattern that has a first char, or |
/* For an anchored pattern, or an unanchored pattern that has a first char, or |
| 888 |
a multiline pattern that matches only at "line starts", there is no point in |
a multiline pattern that matches only at "line starts", there is no point in |
| 889 |
seeking a list of starting bytes. */ |
seeking a list of starting bytes. */ |
| 890 |
|
|
| 891 |
if ((re->options & PCRE_ANCHORED) == 0 && |
if ((re->options & PCRE_ANCHORED) == 0 && |
| 892 |
(re->flags & (PCRE_FIRSTSET|PCRE_STARTLINE)) == 0) |
(re->flags & (PCRE_FIRSTSET|PCRE_STARTLINE)) == 0) |
| 893 |
{ |
{ |
| 894 |
/* Set the character tables in the block that is passed around */ |
/* Set the character tables in the block that is passed around */ |
| 895 |
|
|
| 896 |
tables = re->tables; |
tables = re->tables; |
| 897 |
if (tables == NULL) |
if (tables == NULL) |
| 898 |
(void)pcre_fullinfo(external_re, NULL, PCRE_INFO_DEFAULT_TABLES, |
(void)pcre_fullinfo(external_re, NULL, PCRE_INFO_DEFAULT_TABLES, |
| 899 |
(void *)(&tables)); |
(void *)(&tables)); |
| 900 |
|
|
| 901 |
compile_block.lcc = tables + lcc_offset; |
compile_block.lcc = tables + lcc_offset; |
| 902 |
compile_block.fcc = tables + fcc_offset; |
compile_block.fcc = tables + fcc_offset; |
| 903 |
compile_block.cbits = tables + cbits_offset; |
compile_block.cbits = tables + cbits_offset; |
| 904 |
compile_block.ctypes = tables + ctypes_offset; |
compile_block.ctypes = tables + ctypes_offset; |
| 905 |
|
|
| 906 |
/* See if we can find a fixed set of initial characters for the pattern. */ |
/* See if we can find a fixed set of initial characters for the pattern. */ |
| 907 |
|
|
| 908 |
memset(start_bits, 0, 32 * sizeof(uschar)); |
memset(start_bits, 0, 32 * sizeof(uschar)); |
| 909 |
bits_set = set_start_bits(code, start_bits, |
bits_set = set_start_bits(code, start_bits, |
| 910 |
(re->options & PCRE_CASELESS) != 0, (re->options & PCRE_UTF8) != 0, |
(re->options & PCRE_CASELESS) != 0, (re->options & PCRE_UTF8) != 0, |
| 911 |
&compile_block) == SSB_DONE; |
&compile_block) == SSB_DONE; |
| 912 |
} |
} |
| 913 |
|
|
| 914 |
/* Find the minimum length of subject string. */ |
/* Find the minimum length of subject string. */ |
| 915 |
|
|
| 916 |
min = find_minlength(code, code, re->options); |
min = find_minlength(code, code, re->options); |
| 947 |
study->flags |= PCRE_STUDY_MAPPED; |
study->flags |= PCRE_STUDY_MAPPED; |
| 948 |
memcpy(study->start_bits, start_bits, sizeof(start_bits)); |
memcpy(study->start_bits, start_bits, sizeof(start_bits)); |
| 949 |
} |
} |
| 950 |
|
|
| 951 |
if (min >= 0) |
if (min >= 0) |
| 952 |
{ |
{ |
| 953 |
study->flags |= PCRE_STUDY_MINLEN; |
study->flags |= PCRE_STUDY_MINLEN; |
| 954 |
study->minlength = min; |
study->minlength = min; |
| 955 |
} |
} |
| 956 |
|
|
| 957 |
return extra; |
return extra; |
| 958 |
} |
} |