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Diffstat (limited to 'pcre.c')
| -rw-r--r-- | pcre.c | 3510 |
1 files changed, 3510 insertions, 0 deletions
@@ -0,0 +1,3510 @@ +/************************************************* +* Perl-Compatible Regular Expressions * +*************************************************/ + +/* +This is a library of functions to support regular expressions whose syntax +and semantics are as close as possible to those of the Perl 5 language. See +the file Tech.Notes for some information on the internals. + +Written by: Philip Hazel <ph10@cam.ac.uk> + + Copyright (c) 1997 University of Cambridge + +----------------------------------------------------------------------------- +Permission is granted to anyone to use this software for any purpose on any +computer system, and to redistribute it freely, subject to the following +restrictions: + +1. This software is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. + +2. The origin of this software must not be misrepresented, either by + explicit claim or by omission. + +3. Altered versions must be plainly marked as such, and must not be + misrepresented as being the original software. +----------------------------------------------------------------------------- +*/ + + +/* Define DEBUG to get debugging output on stdout. */ + +/* #define DEBUG */ + + +/* Include the internals header, which itself includes Standard C headers plus +the external pcre header. */ + +#include "internal.h" + + +/* Min and max values for the common repeats; for the maxima, 0 => infinity */ + +static char rep_min[] = { 0, 0, 1, 1, 0, 0 }; +static char rep_max[] = { 0, 0, 0, 0, 1, 1 }; + +/* Text forms of OP_ values and things, for debugging */ + +#ifdef DEBUG +static char *OP_names[] = { "End", "\\A", "\\B", "\\b", "\\D", "\\d", + "\\S", "\\s", "\\W", "\\w", "Cut", "\\Z", "^", "$", "Any", "chars", + "not", + "*", "*?", "+", "+?", "?", "??", "{", "{", "{", + "*", "*?", "+", "+?", "?", "??", "{", "{", "{", + "*", "*?", "+", "+?", "?", "??", "{", "{", "{", + "*", "*?", "+", "+?", "?", "??", "{", "{", + "class", "Ref", + "Alt", "Ket", "KetRmax", "KetRmin", "Assert", "Assert not", "Once", + "Brazero", "Braminzero", "Bra" +}; +#endif + +/* Table for handling escaped characters in the range '0'-'z'. Positive returns +are simple data values; negative values are for special things like \d and so +on. Zero means further processing is needed (for things like \x), or the escape +is invalid. */ + +static short int escapes[] = { + 0, 0, 0, 0, 0, 0, 0, 0, /* 0 - 7 */ + 0, 0, ':', ';', '<', '=', '>', '?', /* 8 - ? */ + '@', -ESC_A, -ESC_B, 0, -ESC_D, 0, 0, 0, /* @ - G */ + 0, 0, 0, 0, 0, 0, 0, 0, /* H - O */ + 0, 0, 0, -ESC_S, 0, 0, 0, -ESC_W, /* P - W */ + 0, 0, -ESC_Z, '[', '\\', ']', '^', '_', /* X - _ */ + '`', 7, -ESC_b, 0, -ESC_d, 27, '\f', 0, /* ` - g */ + 0, 0, 0, 0, 0, 0, '\n', 0, /* h - o */ + 0, 0, '\r', -ESC_s, '\t', 0, 0, -ESC_w, /* p - w */ + 0, 0, 0 /* x - z */ +}; + +/* Definition to allow mutual recursion */ + +static BOOL compile_regex(int, int *,uschar **,uschar **,char **); + +/* Structure for passing "static" information around between the functions +doing the matching, so that they are thread-safe. */ + +typedef struct match_data { + int errorcode; /* As it says */ + int *offset_vector; /* Offset vector */ + int offset_end; /* One past the end */ + BOOL offset_overflow; /* Set if too many extractions */ + BOOL caseless; /* Case-independent flag */ + BOOL runtime_caseless; /* Caseless forced at run time */ + BOOL multiline; /* Multiline flag */ + BOOL notbol; /* NOTBOL flag */ + BOOL noteol; /* NOTEOL flag */ + BOOL dotall; /* Dot matches any char */ + BOOL endonly; /* Dollar not before final \n */ + uschar *start_subject; /* Start of the subject string */ + uschar *end_subject; /* End of the subject string */ + jmp_buf fail_env; /* Environment for longjump() break out */ + uschar *end_match_ptr; /* Subject position at end match */ + int end_offset_top; /* Highwater mark at end of match */ +} match_data; + + + +/************************************************* +* Global variables * +*************************************************/ + +/* PCRE is thread-clean and doesn't use any global variables in the normal +sense. However, it calls memory allocation and free functions via the two +indirections below, which are can be changed by the caller, but are shared +between all threads. */ + +void *(*pcre_malloc)(size_t) = malloc; +void (*pcre_free)(void *) = free; + + + + +/************************************************* +* Return version string * +*************************************************/ + +char * +pcre_version(void) +{ +return PCRE_VERSION; +} + + + + +/************************************************* +* Return info about a compiled pattern * +*************************************************/ + +/* This function picks potentially useful data out of the private +structure. + +Arguments: + external_re points to compiled code + optptr where to pass back the options + first_char where to pass back the first character, + or -1 if multiline and all branches start ^, + or -2 otherwise + +Returns: number of identifying extraction brackets + or negative values on error +*/ + +int +pcre_info(const pcre *external_re, int *optptr, int *first_char) +{ +real_pcre *re = (real_pcre *)external_re; +if (re == NULL) return PCRE_ERROR_NULL; +if (re->magic_number != MAGIC_NUMBER) return PCRE_ERROR_BADMAGIC; +if (optptr != NULL) *optptr = (re->options & PUBLIC_OPTIONS); +if (first_char != NULL) + *first_char = ((re->options & PCRE_FIRSTSET) != 0)? re->first_char : + ((re->options & PCRE_STARTLINE) != 0)? -1 : -2; +return re->top_bracket; +} + + + + +#ifdef DEBUG +/************************************************* +* Debugging function to print chars * +*************************************************/ + +/* Print a sequence of chars in printable format, stopping at the end of the +subject if the requested. + +Arguments: + p points to characters + length number to print + is_subject TRUE if printing from within md->start_subject + md pointer to matching data block, if is_subject is TRUE + +Returns: nothing +*/ + +static pchars(uschar *p, int length, BOOL is_subject, match_data *md) +{ +int c; +if (is_subject && length > md->end_subject - p) length = md->end_subject - p; +while (length-- > 0) + if (isprint(c = *(p++))) printf("%c", c); else printf("\\x%02x", c); +} +#endif + + + + +/************************************************* +* Check subpattern for empty operand * +*************************************************/ + +/* This function checks a bracketed subpattern to see if any of the paths +through it could match an empty string. This is used to diagnose an error if +such a subpattern is followed by a quantifier with an unlimited upper bound. + +Argument: + code points to the opening bracket + +Returns: TRUE or FALSE +*/ + +static BOOL +could_be_empty(uschar *code) +{ +do { + uschar *cc = code + 3; + + /* Scan along the opcodes for this branch; as soon as we find something + that matches a non-empty string, break out and advance to test the next + branch. If we get to the end of the branch, return TRUE for the whole + sub-expression. */ + + for (;;) + { + /* Test an embedded subpattern; if it could not be empty, break the + loop. Otherwise carry on in the branch. */ + + if ((int)(*cc) >= OP_BRA) + { + if (!could_be_empty(cc)) break; + do cc += (cc[1] << 8) + cc[2]; while (*cc == OP_ALT); + cc += 3; + } + + else switch (*cc) + { + /* Reached end of a branch: the subpattern may match the empty string */ + + case OP_ALT: + case OP_KET: + case OP_KETRMAX: + case OP_KETRMIN: + return TRUE; + + /* Skip over assertive subpatterns */ + + case OP_ASSERT: + case OP_ASSERT_NOT: + do cc += (cc[1] << 8) + cc[2]; while (*cc == OP_ALT); + cc += 3; + break; + + /* Skip over things that don't match chars */ + + case OP_SOD: + case OP_EOD: + case OP_CIRC: + case OP_DOLL: + case OP_BRAZERO: + case OP_BRAMINZERO: + case OP_NOT_WORD_BOUNDARY: + case OP_WORD_BOUNDARY: + cc++; + break; + + /* Skip over simple repeats with zero lower bound */ + + case OP_STAR: + case OP_MINSTAR: + case OP_QUERY: + case OP_MINQUERY: + case OP_TYPESTAR: + case OP_TYPEMINSTAR: + case OP_TYPEQUERY: + case OP_TYPEMINQUERY: + cc += 2; + break; + + /* Skip over UPTOs (lower bound is zero) */ + + case OP_UPTO: + case OP_MINUPTO: + case OP_TYPEUPTO: + case OP_TYPEMINUPTO: + cc += 4; + break; + + /* Check a class or a back reference for a zero minimum */ + + case OP_CLASS: + case OP_REF: + cc += (*cc == OP_REF)? 2 : 4 + 2 * cc[2] + cc[3]; + + switch (*cc) + { + case OP_CRSTAR: + case OP_CRMINSTAR: + case OP_CRQUERY: + case OP_CRMINQUERY: + cc++; + break; + + case OP_CRRANGE: + case OP_CRMINRANGE: + if ((cc[1] << 8) + cc[2] != 0) goto NEXT_BRANCH; + cc += 3; + break; + + default: + goto NEXT_BRANCH; + } + break; + + /* Anything else matches at least one character */ + + default: + goto NEXT_BRANCH; + } + } + + NEXT_BRANCH: + code += (code[1] << 8) + code[2]; + } +while (*code == OP_ALT); + +/* No branches match the empty string */ + +return FALSE; +} + + + +/************************************************* +* Handle escapes * +*************************************************/ + +/* This function is called when a \ has been encountered. It either returns a +positive value for a simple escape such as \n, or a negative value which +encodes one of the more complicated things such as \d. On entry, ptr is +pointing at the \. On exit, it is on the final character of the escape +sequence. + +Arguments: + ptrptr points to the pattern position pointer + errorptr points to the pointer to the error message + bracount number of previous extracting brackets + options the options bits + isclass TRUE if inside a character class + +Returns: zero or positive => a data character + negative => a special escape sequence + on error, errorptr is set +*/ + +static int +check_escape(uschar **ptrptr, char **errorptr, int bracount, int options, + BOOL isclass) +{ +uschar *ptr = *ptrptr; +int c = *(++ptr) & 255; /* Ensure > 0 on signed-char systems */ +int i; + +if (c == 0) *errorptr = ERR1; + +/* Digits or letters may have special meaning; all others are literals. */ + +else if (c < '0' || c > 'z') {} + +/* Do an initial lookup in a table. A non-zero result is something that can be +returned immediately. Otherwise further processing may be required. */ + +else if ((i = escapes[c - '0']) != 0) c = i; + +/* Escapes that need further processing, or are illegal. */ + +else + { + uschar *oldptr; + switch (c) + { + /* The handling of escape sequences consisting of a string of digits + starting with one that is not zero is not straightforward. By experiment, + the way Perl works seems to be as follows: + + Outside a character class, the digits are read as a decimal number. If the + number is less than 10, or if there are that many previous extracting + left brackets, then it is a back reference. Otherwise, up to three octal + digits are read to form an escaped byte. Thus \123 is likely to be octal + 123 (cf \0123, which is octal 012 followed by the literal 3). If the octal + value is greater than 377, the least significant 8 bits are taken. Inside a + character class, \ followed by a digit is always an octal number. */ + + case '1': case '2': case '3': case '4': case '5': + case '6': case '7': case '8': case '9': + + if (!isclass) + { + oldptr = ptr; + c -= '0'; + while ((pcre_ctypes[ptr[1]] & ctype_digit) != 0) + c = c * 10 + *(++ptr) - '0'; + if (c < 10 || c <= bracount) + { + c = -(ESC_REF + c); + break; + } + ptr = oldptr; /* Put the pointer back and fall through */ + } + + /* Handle an octal number following \. If the first digit is 8 or 9, Perl + generates a binary zero byte and treats the digit as a following literal. + Thus we have to pull back the pointer by one. */ + + if ((c = *ptr) >= '8') + { + ptr--; + c = 0; + break; + } + + /* \0 always starts an octal number, but we may drop through to here with a + larger first octal digit */ + + case '0': + c -= '0'; + while(i++ < 2 && (pcre_ctypes[ptr[1]] & ctype_digit) != 0 && + ptr[1] != '8' && ptr[1] != '9') + c = c * 8 + *(++ptr) - '0'; + break; + + /* Special escapes not starting with a digit are straightforward */ + + case 'x': + c = 0; + while (i++ < 2 && (pcre_ctypes[ptr[1]] & ctype_xdigit) != 0) + { + ptr++; + c = c * 16 + pcre_lcc[*ptr] - + (((pcre_ctypes[*ptr] & ctype_digit) != 0)? '0' : 'W'); + } + break; + + case 'c': + c = *(++ptr); + if (c == 0) + { + *errorptr = ERR2; + return 0; + } + + /* A letter is upper-cased; then the 0x40 bit is flipped */ + + if (c >= 'a' && c <= 'z') c = pcre_fcc[c]; + c ^= 0x40; + break; + + /* PCRE_EXTRA enables extensions to Perl in the matter of escapes. Any + other alphameric following \ is an error if PCRE_EXTRA was set; otherwise, + for Perl compatibility, it is a literal. */ + + default: + if ((options & PCRE_EXTRA) != 0) switch(c) + { + case 'X': + c = -ESC_X; /* This could be a lookup if it ever got into Perl */ + break; + + default: + *errorptr = ERR3; + break; + } + break; + } + } + +*ptrptr = ptr; +return c; +} + + + +/************************************************* +* Check for counted repeat * +*************************************************/ + +/* This function is called when a '{' is encountered in a place where it might +start a quantifier. It looks ahead to see if it really is a quantifier or not. +It is only a quantifier if it is one of the forms {ddd} {ddd,} or {ddd,ddd} +where the ddds are digits. + +Arguments: + p pointer to the first char after '{' + +Returns: TRUE or FALSE +*/ + +static BOOL +is_counted_repeat(uschar *p) +{ +if ((pcre_ctypes[*p++] & ctype_digit) == 0) return FALSE; +while ((pcre_ctypes[*p] & ctype_digit) != 0) p++; +if (*p == '}') return TRUE; + +if (*p++ != ',') return FALSE; +if (*p == '}') return TRUE; + +if ((pcre_ctypes[*p++] & ctype_digit) == 0) return FALSE; +while ((pcre_ctypes[*p] & ctype_digit) != 0) p++; +return (*p == '}'); +} + + + +/************************************************* +* Read repeat counts * +*************************************************/ + +/* Read an item of the form {n,m} and return the values. This is called only +after is_counted_repeat() has confirmed that a repeat-count quantifier exists, +so the syntax is guaranteed to be correct, but we need to check the values. + +Arguments: + p pointer to first char after '{' + minp pointer to int for min + maxp pointer to int for max + returned as -1 if no max + errorptr points to pointer to error message + +Returns: pointer to '}' on success; + current ptr on error, with errorptr set +*/ + +static uschar * +read_repeat_counts(uschar *p, int *minp, int *maxp, char **errorptr) +{ +int min = 0; +int max = -1; + +while ((pcre_ctypes[*p] & ctype_digit) != 0) min = min * 10 + *p++ - '0'; + +if (*p == '}') max = min; else + { + if (*(++p) != '}') + { + max = 0; + while((pcre_ctypes[*p] & ctype_digit) != 0) max = max * 10 + *p++ - '0'; + if (max < min) + { + *errorptr = ERR4; + return p; + } + } + } + +/* Do paranoid checks, then fill in the required variables, and pass back the +pointer to the terminating '}'. */ + +if (min > 65535 || max > 65535) + *errorptr = ERR5; +else + { + *minp = min; + *maxp = max; + } +return p; +} + + + +/************************************************* +* Compile one branch * +*************************************************/ + +/* Scan the pattern, compiling it into the code vector. + +Arguments: + options the option bits + bracket points to number of brackets used + code points to the pointer to the current code point + ptrptr points to the current pattern pointer + errorptr points to pointer to error message + +Returns: TRUE on success + FALSE, with *errorptr set on error +*/ + +static BOOL +compile_branch(int options, int *brackets, uschar **codeptr, uschar **ptrptr, + char **errorptr) +{ +int repeat_type, op_type; +int repeat_min, repeat_max; +int bravalue, length; +register int c; +register uschar *code = *codeptr; +uschar *ptr = *ptrptr; +uschar *previous = NULL; +uschar *oldptr; +uschar class[32]; + +/* Switch on next character until the end of the branch */ + +for (;; ptr++) + { + BOOL negate_class; + int class_charcount; + int class_lastchar; + + c = *ptr; + if ((options & PCRE_EXTENDED) != 0) + { + if ((pcre_ctypes[c] & ctype_space) != 0) continue; + if (c == '#') + { + while ((c = *(++ptr)) != 0 && c != '\n'); + continue; + } + } + + switch(c) + { + /* The branch terminates at end of string, |, or ). */ + + case 0: + case '|': + case ')': + *codeptr = code; + *ptrptr = ptr; + return TRUE; + + /* Handle single-character metacharacters */ + + case '^': + previous = NULL; + *code++ = OP_CIRC; + break; + + case '$': + previous = NULL; + *code++ = OP_DOLL; + break; + + case '.': + previous = code; + *code++ = OP_ANY; + break; + + /* Character classes. These always build a 32-byte bitmap of the permitted + characters, except in the special case where there is only one character. + For negated classes, we build the map as usual, then invert it at the end. + */ + + case '[': + previous = code; + *code++ = OP_CLASS; + + /* If the first character is '^', set the negation flag */ + + if ((c = *(++ptr)) == '^') + { + negate_class = TRUE; + c = *(++ptr); + } + else negate_class = FALSE; + + /* Keep a count of chars so that we can optimize the case of just a single + character. */ + + class_charcount = 0; + class_lastchar = -1; + + /* Initialize the 32-char bit map to all zeros. We have to build the + map in a temporary bit of store, in case the class contains only 1 + character, because in that case the compiled code doesn't use the + bit map. */ + + memset(class, 0, 32 * sizeof(uschar)); + + /* Process characters until ] is reached. By writing this as a "do" it + means that an initial ] is taken as a data character. */ + + do + { + if (c == 0) + { + *errorptr = ERR6; + goto FAILED; + } + + /* Backslash may introduce a single character, or it may introduce one + of the specials, which just set a flag. Escaped items are checked for + validity in the pre-compiling pass. The sequence \b is a special case. + Inside a class (and only there) it is treated as backslash. Elsewhere + it marks a word boundary. Other escapes have preset maps ready to + or into the one we are building. We assume they have more than one + character in them, so set class_count bigger than one. */ + + if (c == '\\') + { + c = check_escape(&ptr, errorptr, *brackets, options, TRUE); + if (-c == ESC_b) c = '\b'; + else if (c < 0) + { + class_charcount = 10; + switch (-c) + { + case ESC_d: + for (c = 0; c < 32; c++) class[c] |= pcre_cbits[c+cbit_digit]; + continue; + + case ESC_D: + for (c = 0; c < 32; c++) class[c] |= ~pcre_cbits[c+cbit_digit]; + continue; + + case ESC_w: + for (c = 0; c < 32; c++) + class[c] |= (pcre_cbits[c] | pcre_cbits[c+cbit_word]); + continue; + + case ESC_W: + for (c = 0; c < 32; c++) + class[c] |= ~(pcre_cbits[c] | pcre_cbits[c+cbit_word]); + continue; + + case ESC_s: + for (c = 0; c < 32; c++) class[c] |= pcre_cbits[c+cbit_space]; + continue; + + case ESC_S: + for (c = 0; c < 32; c++) class[c] |= ~pcre_cbits[c+cbit_space]; + continue; + + default: + *errorptr = ERR7; + goto FAILED; + } + } + /* Fall through if single character */ + } + + /* A single character may be followed by '-' to form a range. However, + Perl does not permit ']' to be the end of the range. A '-' character + here is treated as a literal. */ + + if (ptr[1] == '-' && ptr[2] != ']') + { + int d; + ptr += 2; + d = *ptr; + + if (d == 0) + { + *errorptr = ERR6; + goto FAILED; + } + + /* The second part of a range can be a single-character escape, but + not any of the other escapes. */ + + if (d == '\\') + { + d = check_escape(&ptr, errorptr, *brackets, options, TRUE); + if (d < 0) + { + if (d == -ESC_b) d = '\b'; else + { + *errorptr = ERR7; + goto FAILED; + } + } + } + + if (d < c) + { + *errorptr = ERR8; + goto FAILED; + } + + for (; c <= d; c++) + { + class[c/8] |= (1 << (c&7)); + if ((options & PCRE_CASELESS) != 0) + { + int uc = pcre_fcc[c]; /* flip case */ + class[uc/8] |= (1 << (uc&7)); + } + class_charcount++; /* in case a one-char range */ + class_lastchar = c; + } + continue; /* Go get the next char in the class */ + } + + /* Handle a lone single character - we can get here for a normal + non-escape char, or after \ that introduces a single character. */ + + class [c/8] |= (1 << (c&7)); + if ((options & PCRE_CASELESS) != 0) + { + c = pcre_fcc[c]; /* flip case */ + class[c/8] |= (1 << (c&7)); + } + class_charcount++; + class_lastchar = c; + } + + /* Loop until ']' reached; the check for end of string happens inside the + loop. This "while" is the end of the "do" above. */ + + while ((c = *(++ptr)) != ']'); + + /* If class_charcount is 1 and class_lastchar is not negative, we saw + precisely one character. This doesn't need the whole 32-byte bit map. + We turn it into a 1-character OP_CHAR if it's positive, or OP_NOT if + it's negative. */ + + if (class_charcount == 1 && class_lastchar >= 0) + { + if (negate_class) + { + code[-1] = OP_NOT; + } + else + { + code[-1] = OP_CHARS; + *code++ = 1; + } + *code++ = class_lastchar; + } + + /* Otherwise, negate the 32-byte map if necessary, and copy it into + the code vector. */ + + else + { + if (negate_class) + for (c = 0; c < 32; c++) code[c] = ~class[c]; + else + memcpy(code, class, 32); + code += 32; + } + break; + + /* Various kinds of repeat */ + + case '{': + if (!is_counted_repeat(ptr+1)) goto NORMAL_CHAR; + ptr = read_repeat_counts(ptr+1, &repeat_min, &repeat_max, errorptr); + if (*errorptr != NULL) goto FAILED; + goto REPEAT; + + case '*': + repeat_min = 0; + repeat_max = -1; + goto REPEAT; + + case '+': + repeat_min = 1; + repeat_max = -1; + goto REPEAT; + + case '?': + repeat_min = 0; + repeat_max = 1; + + REPEAT: + if (previous == NULL) + { + *errorptr = ERR9; + goto FAILED; + } + + /* If the next character is '?' this is a minimizing repeat. Advance to the + next character. */ + + if (ptr[1] == '?') { repeat_type = 1; ptr++; } else repeat_type = 0; + + /* If the maximum is zero then the minimum must also be zero; Perl allows + this case, so we do too - by simply omitting the item altogether. */ + + if (repeat_max == 0) code = previous; + + /* If previous was a string of characters, chop off the last one and use it + as the subject of the repeat. If there was only one character, we can + abolish the previous item altogether. */ + + else if (*previous == OP_CHARS) + { + int len = previous[1]; + if (len == 1) + { + c = previous[2]; + code = previous; + } + else + { + c = previous[len+1]; + previous[1]--; + code--; + } + op_type = 0; /* Use single-char op codes */ + goto OUTPUT_SINGLE_REPEAT; /* Code shared with single character types */ + } + + /* If previous was a single negated character ([^a] or similar), we use + one of the special opcodes, replacing it. The code is shared with single- + character repeats by adding a suitable offset into repeat_type. */ + + else if ((int)*previous == OP_NOT) + { + op_type = OP_NOTSTAR - OP_STAR; /* Use "not" opcodes */ + c = previous[1]; + code = previous; + goto OUTPUT_SINGLE_REPEAT; + } + + /* If previous was a character type match (\d or similar), abolish it and + create a suitable repeat item. The code is shared with single-character + repeats by adding a suitable offset into repeat_type. */ + + else if ((int)*previous < OP_EOD || *previous == OP_ANY) + { + op_type = OP_TYPESTAR - OP_STAR; /* Use type opcodes */ + c = *previous; + code = previous; + + OUTPUT_SINGLE_REPEAT: + repeat_type += op_type; /* Combine both values for many cases */ + + /* A minimum of zero is handled either as the special case * or ?, or as + an UPTO, with the maximum given. */ + + if (repeat_min == 0) + { + if (repeat_max == -1) *code++ = OP_STAR + repeat_type; + else if (repeat_max == 1) *code++ = OP_QUERY + repeat_type; + else + { + *code++ = OP_UPTO + repeat_type; + *code++ = repeat_max >> 8; + *code++ = (repeat_max & 255); + } + } + + /* The case {1,} is handled as the special case + */ + + else if (repeat_min == 1 && repeat_max == -1) + *code++ = OP_PLUS + repeat_type; + + /* The case {n,n} is just an EXACT, while the general case {n,m} is + handled as an EXACT followed by an UPTO. An EXACT of 1 is optimized. */ + + else + { + if (repeat_min != 1) + { + *code++ = OP_EXACT + op_type; /* NB EXACT doesn't have repeat_type */ + *code++ = repeat_min >> 8; + *code++ = (repeat_min & 255); + } + + /* If the mininum is 1 and the previous item was a character string, + we either have to put back the item that got cancelled if the string + length was 1, or add the character back onto the end of a longer + string. For a character type nothing need be done; it will just get put + back naturally. */ + + else if (*previous == OP_CHARS) + { + if (code == previous) code += 2; else previous[1]++; + } + + /* Insert an UPTO if the max is greater than the min. */ + + if (repeat_max != repeat_min) + { + *code++ = c; + repeat_max -= repeat_min; + *code++ = OP_UPTO + repeat_type; + *code++ = repeat_max >> 8; + *code++ = (repeat_max & 255); + } + } + + /* The character or character type itself comes last in all cases. */ + + *code++ = c; + } + + /* If previous was a character class or a back reference, we put the repeat + stuff after it. */ + + else if (*previous == OP_CLASS || *previous == OP_REF) + { + if (repeat_min == 0 && repeat_max == -1) + *code++ = OP_CRSTAR + repeat_type; + else if (repeat_min == 1 && repeat_max == -1) + *code++ = OP_CRPLUS + repeat_type; + else if (repeat_min == 0 && repeat_max == 1) + *code++ = OP_CRQUERY + repeat_type; + else + { + *code++ = OP_CRRANGE + repeat_type; + *code++ = repeat_min >> 8; + *code++ = repeat_min & 255; + if (repeat_max == -1) repeat_max = 0; /* 2-byte encoding for max */ + *code++ = repeat_max >> 8; + *code++ = repeat_max & 255; + } + } + + /* If previous was a bracket group, we may have to replicate it in certain + cases. If the maximum repeat count is unlimited, check that the bracket + group cannot match the empty string, and diagnose an error if it can. */ + + else if ((int)*previous >= OP_BRA) + { + int i; + int length = code - previous; + + if (repeat_max == -1 && could_be_empty(previous)) + { + *errorptr = ERR10; + goto FAILED; + } + + /* If the minimum is greater than zero, and the maximum is unlimited or + equal to the minimum, the first copy remains where it is, and is + replicated up to the minimum number of times. This case includes the + + repeat, but of course no replication is needed in that case. */ + + if (repeat_min > 0 && (repeat_max == -1 || repeat_max == repeat_min)) + { + for (i = 1; i < repeat_min; i++) + { + memcpy(code, previous, length); + code += length; + } + } + + /* If the minimum is zero, stick BRAZERO in front of the first copy. + Then, if there is a fixed upper limit, replicated up to that many times, + sticking BRAZERO in front of all the optional ones. */ + + else + { + if (repeat_min == 0) + { + memmove(previous+1, previous, length); + code++; + *previous++ = OP_BRAZERO + repeat_type; + } + + for (i = 1; i < repeat_min; i++) + { + memcpy(code, previous, length); + code += length; + } + + for (i = (repeat_min > 0)? repeat_min : 1; i < repeat_max; i++) + { + *code++ = OP_BRAZERO + repeat_type; + memcpy(code, previous, length); + code += length; + } + } + + /* If the maximum is unlimited, set a repeater in the final copy. */ + + if (repeat_max == -1) code[-3] = OP_KETRMAX + repeat_type; + } + + /* Else there's some kind of shambles */ + + else + { + *errorptr = ERR11; + goto FAILED; + } + + /* In all case we no longer have a previous item. */ + + previous = NULL; + break; + + + /* Start of nested bracket sub-expression, or comment or lookahead. + First deal with special things that can come after a bracket; all are + introduced by ?, and the appearance of any of them means that this is not a + referencing group. They were checked for validity in the first pass over + the string, so we don't have to check for syntax errors here. */ + + case '(': + previous = code; /* Only real brackets can be repeated */ + if (*(++ptr) == '?') + { + bravalue = OP_BRA; + + switch (*(++ptr)) + { + case '#': + case 'i': + case 'm': + case 's': + case 'x': + ptr++; + while (*ptr != ')') ptr++; + previous = NULL; + continue; + + case ':': /* Non-extracting bracket */ + ptr++; + break; + + case '=': /* Assertions can't be repeated */ + bravalue = OP_ASSERT; + ptr++; + previous = NULL; + break; + + case '!': + bravalue = OP_ASSERT_NOT; + ptr++; + previous = NULL; + break; + + case '>': /* "Match once" brackets */ + if ((options & PCRE_EXTRA) != 0) /* Not yet standard */ + { + bravalue = OP_ONCE; + ptr++; + previous = NULL; + break; + } + /* Else fall through */ + + default: + *errorptr = ERR12; + goto FAILED; + } + } + + /* Else we have a referencing group */ + + else + { + if (++(*brackets) > EXTRACT_MAX) + { + *errorptr = ERR13; + goto FAILED; + } + bravalue = OP_BRA + *brackets; + } + + /* Process nested bracketed re; at end pointer is on the bracket. We copy + code into a non-register variable in order to be able to pass its address + because some compilers complain otherwise. */ + + *code = bravalue; + { + uschar *mcode = code; + if (!compile_regex(options, brackets, &mcode, &ptr, errorptr)) + goto FAILED; + code = mcode; + } + + if (*ptr != ')') + { + *errorptr = ERR14; + goto FAILED; + } + break; + + /* Check \ for being a real metacharacter; if not, fall through and handle + it as a data character at the start of a string. Escape items are checked + for validity in the pre-compiling pass. */ + + case '\\': + oldptr = ptr; + c = check_escape(&ptr, errorptr, *brackets, options, FALSE); + + /* Handle metacharacters introduced by \. For ones like \d, the ESC_ values + are arranged to be the negation of the corresponding OP_values. For the + back references, the values are ESC_REF plus the reference number. Only + back references and those types that consume a character may be repeated. + We can test for values between ESC_b and ESC_Z for the latter; this may + have to change if any new ones are ever created. */ + + if (c < 0) + { + if (-c >= ESC_REF) + { + int refnum = -c - ESC_REF; + if (*brackets < refnum) + { + *errorptr = ERR15; + goto FAILED; + } + previous = code; + *code++ = OP_REF; + *code++ = refnum; + } + else + { + previous = (-c > ESC_b && -c < ESC_X)? code : NULL; + *code++ = -c; + } + continue; + } + + /* Reset and fall through */ + + ptr = oldptr; + c = '\\'; + + /* Handle a run of data characters until a metacharacter is encountered. + The first character is guaranteed not to be whitespace or # when the + extended flag is set. */ + + NORMAL_CHAR: + default: + previous = code; + *code = OP_CHARS; + code += 2; + length = 0; + + do + { + if ((options & PCRE_EXTENDED) != 0) + { + if ((pcre_ctypes[c] & ctype_space) != 0) continue; + if (c == '#') + { + while ((c = *(++ptr)) != 0 && c != '\n'); + if (c == 0) break; + continue; + } + } + + /* Backslash may introduce a data char or a metacharacter. Escaped items + are checked for validity in the pre-compiling pass. Stop the string + before a metaitem. */ + + if (c == '\\') + { + oldptr = ptr; + c = check_escape(&ptr, errorptr, *brackets, options, FALSE); + if (c < 0) { ptr = oldptr; break; } + } + + /* Ordinary character or single-char escape */ + + *code++ = c; + length++; + } + + /* This "while" is the end of the "do" above. */ + + while (length < 255 && (pcre_ctypes[c = *(++ptr)] & ctype_meta) == 0); + + /* Compute the length and set it in the data vector, and advance to + the next state. */ + + previous[1] = length; + ptr--; + break; + } + } /* end of big loop */ + +/* Control never reaches here by falling through, only by a goto for all the +error states. Pass back the position in the pattern so that it can be displayed +to the user for diagnosing the error. */ + +FAILED: +*ptrptr = ptr; +return FALSE; +} + + + + +/************************************************* +* Compile sequence of alternatives * +*************************************************/ + +/* On entry, ptr is pointing past the bracket character, but on return +it points to the closing bracket, or vertical bar, or end of string. +The code variable is pointing at the byte into which the BRA operator has been +stored. + +Argument: + options the option bits + brackets -> int containing the number of extracting brackets used + codeptr -> the address of the current code pointer + ptrptr -> the address of the current pattern pointer + errorptr -> pointer to error message + +Returns: TRUE on success +*/ + +static BOOL +compile_regex(int options, int *brackets, uschar **codeptr, uschar **ptrptr, + char **errorptr) +{ +uschar *ptr = *ptrptr; +uschar *code = *codeptr; +uschar *start_bracket = code; + +for (;;) + { + int length; + uschar *last_branch = code; + + code += 3; + if (!compile_branch(options, brackets, &code, &ptr, errorptr)) + { + *ptrptr = ptr; + return FALSE; + } + + /* Fill in the length of the last branch */ + + length = code - last_branch; + last_branch[1] = length >> 8; + last_branch[2] = length & 255; + + /* Reached end of expression, either ')' or end of pattern. Insert a + terminating ket and the length of the whole bracketed item, and return, + leaving the pointer at the terminating char. */ + + if (*ptr != '|') + { + length = code - start_bracket; + *code++ = OP_KET; + *code++ = length >> 8; + *code++ = length & 255; + *codeptr = code; + *ptrptr = ptr; + return TRUE; + } + + /* Another branch follows; insert an "or" node and advance the pointer. */ + + *code = OP_ALT; + ptr++; + } +/* Control never reaches here */ +} + + + +/************************************************* +* Check for anchored expression * +*************************************************/ + +/* Try to find out if this is an anchored regular expression. Consider each +alternative branch. If they all start with OP_SOD or OP_CIRC, or with a bracket +all of whose alternatives start with OP_SOD or OP_CIRC (recurse ad lib), then +it's anchored. However, if this is a multiline pattern, then only OP_SOD +counts, since OP_CIRC can match in the middle. + +A branch is also implicitly anchored if it starts with .* because that will try +the rest of the pattern at all possible matching points, so there is no point +trying them again. + +Argument: points to start of expression (the bracket) +Returns: TRUE or FALSE +*/ + +static BOOL +is_anchored(register uschar *code, BOOL multiline) +{ +do { + int op = (int)code[3]; + if (op >= OP_BRA || op == OP_ASSERT || op == OP_ONCE) + { if (!is_anchored(code+3, multiline)) return FALSE; } + else if (op == OP_TYPESTAR || op == OP_TYPEMINSTAR) + { if (code[4] != OP_ANY) return FALSE; } + else if (op != OP_SOD && (multiline || op != OP_CIRC)) return FALSE; + code += (code[1] << 8) + code[2]; + } +while (*code == OP_ALT); +return TRUE; +} + + + +/************************************************* +* Check for start with \n line expression * +*************************************************/ + +/* This is called for multiline expressions to try to find out if every branch +starts with ^ so that "first char" processing can be done to speed things up. + +Argument: points to start of expression (the bracket) +Returns: TRUE or FALSE +*/ + +static BOOL +is_startline(uschar *code) +{ +do { + if ((int)code[3] >= OP_BRA || code[3] == OP_ASSERT) + { if (!is_startline(code+3)) return FALSE; } + else if (code[3] != OP_CIRC) return FALSE; + code += (code[1] << 8) + code[2]; + } +while (*code == OP_ALT); +return TRUE; +} + + + +/************************************************* +* Check for fixed first char * +*************************************************/ + +/* Try to find out if there is a fixed first character. This is called for +unanchored expressions, as it speeds up their processing quite considerably. +Consider each alternative branch. If they all start with the same char, or with +a bracket all of whose alternatives start with the same char (recurse ad lib), +then we return that char, otherwise -1. + +Argument: points to start of expression (the bracket) +Returns: -1 or the fixed first char +*/ + +static int +find_firstchar(uschar *code) +{ +register int c = -1; +do + { + register int charoffset = 4; + + if ((int)code[3] >= OP_BRA || code[3] == OP_ASSERT) + { + register int d; + if ((d = find_firstchar(code+3)) < 0) return -1; + if (c < 0) c = d; else if (c != d) return -1; + } + + else switch(code[3]) + { + default: + return -1; + + case OP_EXACT: /* Fall through */ + charoffset++; + + case OP_CHARS: /* Fall through */ + charoffset++; + + case OP_PLUS: + case OP_MINPLUS: + if (c < 0) c = code[charoffset]; else if (c != code[charoffset]) return -1; + break; + } + code += (code[1] << 8) + code[2]; + } +while (*code == OP_ALT); +return c; +} + + + +/************************************************* +* Compile a Regular Expression * +*************************************************/ + +/* This function takes a string and returns a pointer to a block of store +holding a compiled version of the expression. + +Arguments: + pattern the regular expression + options various option bits + errorptr pointer to pointer to error text + erroroffset ptr offset in pattern where error was detected + +Returns: pointer to compiled data block, or NULL on error, + with errorptr and erroroffset set +*/ + +pcre * +pcre_compile(const char *pattern, int options, char **errorptr, + int *erroroffset) +{ +real_pcre *re; +int spaces = 0; +int length = 3; /* For initial BRA plus length */ +int runlength; +int c, size; +int bracount = 0; +int brastack[200]; +int brastackptr = 0; +int top_backref = 0; +uschar *code, *ptr; + +#ifdef DEBUG +uschar *code_base, *code_end; +#endif + +/* We can't pass back an error message if errorptr is NULL; I guess the best we +can do is just return NULL. */ + +if (errorptr == NULL) return NULL; +*errorptr = NULL; + +/* However, we can give a message for this error */ + +if (erroroffset == NULL) + { + *errorptr = ERR16; + return NULL; + } +*erroroffset = 0; + +if ((options & ~PUBLIC_OPTIONS) != 0) + { + *errorptr = ERR17; + return NULL; + } + +#ifdef DEBUG +printf("------------------------------------------------------------------\n"); +printf("%s\n", pattern); +#endif + +/* The first thing to do is to make a pass over the pattern to compute the +amount of store required to hold the compiled code. This does not have to be +perfect as long as errors are overestimates. At the same time we can detect any +internal flag settings. Make an attempt to correct for any counted white space +if an "extended" flag setting appears late in the pattern. We can't be so +clever for #-comments. */ + +ptr = (uschar *)(pattern - 1); +while ((c = *(++ptr)) != 0) + { + int min, max; + int class_charcount; + + if ((pcre_ctypes[c] & ctype_space) != 0) + { + if ((options & PCRE_EXTENDED) != 0) continue; + spaces++; + } + + if (c == '#' && (options & PCRE_EXTENDED) != 0) + { + while ((c = *(++ptr)) != 0 && c != '\n'); + continue; + } + + switch(c) + { + /* A backslashed item may be an escaped "normal" character or a + character type. For a "normal" character, put the pointers and + character back so that tests for whitespace etc. in the input + are done correctly. */ + + case '\\': + { + uschar *save_ptr = ptr; + c = check_escape(&ptr, errorptr, bracount, options, FALSE); + if (*errorptr != NULL) goto PCRE_ERROR_RETURN; + if (c >= 0) + { + ptr = save_ptr; + c = '\\'; + goto NORMAL_CHAR; + } + } + length++; + + /* A back reference needs an additional char, plus either one or 5 + bytes for a repeat. We also need to keep the value of the highest + back reference. */ + + if (c <= -ESC_REF) + { + int refnum = -c - ESC_REF; + if (refnum > top_backref) top_backref = refnum; + length++; /* For single back reference */ + if (ptr[1] == '{' && is_counted_repeat(ptr+2)) + { + ptr = read_repeat_counts(ptr+2, &min, &max, errorptr); + if (*errorptr != NULL) goto PCRE_ERROR_RETURN; + if ((min == 0 && (max == 1 || max == -1)) || + (min == 1 && max == -1)) + length++; + else length += 5; + if (ptr[1] == '?') ptr++; + } + } + continue; + + case '^': + case '.': + case '$': + case '*': /* These repeats won't be after brackets; */ + case '+': /* those are handled separately */ + case '?': + length++; + continue; + + /* This covers the cases of repeats after a single char, metachar, class, + or back reference. */ + + case '{': + if (!is_counted_repeat(ptr+1)) goto NORMAL_CHAR; + ptr = read_repeat_counts(ptr+1, &min, &max, errorptr); + if (*errorptr != NULL) goto PCRE_ERROR_RETURN; + if ((min == 0 && (max == 1 || max == -1)) || + (min == 1 && max == -1)) + length++; + else + { + length--; /* Uncount the original char or metachar */ + if (min == 1) length++; else if (min > 0) length += 4; + if (max > 0) length += 4; else length += 2; + } + if (ptr[1] == '?') ptr++; + continue; + + /* An alternation contains an offset to the next branch or ket. */ + case '|': + length += 3; + continue; + + /* A character class uses 33 characters. Don't worry about character types + that aren't allowed in classes - they'll get picked up during the compile. + A character class that contains only one character uses 2 or 3 bytes, + depending on whether it is negated or not. Notice this where we can. */ + + case '[': + class_charcount = 0; + if (*(++ptr) == '^') ptr++; + do + { + if (*ptr == '\\') + { + int c = check_escape(&ptr, errorptr, bracount, options, TRUE); + if (*errorptr != NULL) goto PCRE_ERROR_RETURN; + if (-c == ESC_b) class_charcount++; else class_charcount = 10; + } + else class_charcount++; + ptr++; + } + while (*ptr != 0 && *ptr != ']'); + + /* Repeats for negated single chars are handled by the general code */ + + if (class_charcount == 1) length += 3; else + { + length += 33; + + /* A repeat needs either 1 or 5 bytes. */ + + if (ptr[1] == '{' && is_counted_repeat(ptr+2)) + { + ptr = read_repeat_counts(ptr+2, &min, &max, errorptr); + if (*errorptr != NULL) goto PCRE_ERROR_RETURN; + if ((min == 0 && (max == 1 || max == -1)) || + (min == 1 && max == -1)) + length++; + else length += 5; + if (ptr[1] == '?') ptr++; + } + } + continue; + + /* Brackets may be genuine groups or special things */ + + case '(': + + /* Handle special forms of bracket, which all start (? */ + + if (ptr[1] == '?') switch (c = ptr[2]) + { + /* Skip over comments entirely */ + case '#': + ptr += 3; + while (*ptr != 0 && *ptr != ')') ptr++; + if (*ptr == 0) + { + *errorptr = ERR18; + goto PCRE_ERROR_RETURN; + } + continue; + + /* Non-referencing groups and lookaheads just move the pointer on, and + then behave like a non-special bracket, except that they don't increment + the count of extracting brackets. */ + + case ':': + case '=': + case '!': + ptr += 2; + break; + + /* Ditto for the "once only" bracket, allowed only if the extra bit + is set. */ + + case '>': + if ((options & PCRE_EXTRA) != 0) + { + ptr += 2; + break; + } + /* Else fall thourh */ + + /* Else loop setting valid options until ) is met. Anything else is an + error. */ + + default: + ptr += 2; + for (;; ptr++) + { + if ((c = *ptr) == 'i') + { + options |= PCRE_CASELESS; + continue; + } + else if ((c = *ptr) == 'm') + { + options |= PCRE_MULTILINE; + continue; + } + else if (c == 's') + { + options |= PCRE_DOTALL; + continue; + } + else if (c == 'x') + { + options |= PCRE_EXTENDED; + length -= spaces; /* Already counted spaces */ + continue; + } + else if (c == ')') break; + + *errorptr = ERR12; + goto PCRE_ERROR_RETURN; + } + continue; /* End of this bracket handling */ + } + + /* Extracting brackets must be counted so we can process escapes in a + Perlish way. */ + + else bracount++; + + /* Non-special forms of bracket. Save length for computing whole length + at end if there's a repeat that requires duplication of the group. */ + + if (brastackptr >= sizeof(brastack)/sizeof(int)) + { + *errorptr = ERR19; + goto PCRE_ERROR_RETURN; + } + + brastack[brastackptr++] = length; + length += 3; + continue; + + /* Handle ket. Look for subsequent max/min; for certain sets of values we + have to replicate this bracket up to that many times. */ + + case ')': + length += 3; + { + int min = 1; + int max = 1; + int duplength = length - brastack[--brastackptr]; + + /* Leave ptr at the final char; for read_repeat_counts this happens + automatically; for the others we need an increment. */ + + if ((c = ptr[1]) == '{' && is_counted_repeat(ptr+2)) + { + ptr = read_repeat_counts(ptr+2, &min, &max, errorptr); + if (*errorptr != NULL) goto PCRE_ERROR_RETURN; + } + else if (c == '*') { min = 0; max = -1; ptr++; } + else if (c == '+') { max = -1; ptr++; } + else if (c == '?') { min = 0; ptr++; } + + /* If there is a minimum > 1 we have to replicate up to min-1 times; if + there is a limited maximum we have to replicate up to max-1 times and + allow for a BRAZERO item before each optional copy, as we also have to + do before the first copy if the minimum is zero. */ + + if (min == 0) length++; + else if (min > 1) length += (min - 1) * duplength; + if (max > min) length += (max - min) * (duplength + 1); + } + + continue; + + /* Non-special character. For a run of such characters the length required + is the number of characters + 2, except that the maximum run length is 255. + We won't get a skipped space or a non-data escape or the start of a # + comment as the first character, so the length can't be zero. */ + + NORMAL_CHAR: + default: + length += 2; + runlength = 0; + do + { + if ((pcre_ctypes[c] & ctype_space) != 0) + { + if ((options & PCRE_EXTENDED) != 0) continue; + spaces++; + } + + if (c == '#' && (options & PCRE_EXTENDED) != 0) + { + while ((c = *(++ptr)) != 0 && c != '\n'); + continue; + } + + /* Backslash may introduce a data char or a metacharacter; stop the + string before the latter. */ + + if (c == '\\') + { + uschar *saveptr = ptr; + c = check_escape(&ptr, errorptr, bracount, options, FALSE); + if (*errorptr != NULL) goto PCRE_ERROR_RETURN; + if (c < 0) { ptr = saveptr; break; } + } + + /* Ordinary character or single-char escape */ + + runlength++; + } + + /* This "while" is the end of the "do" above. */ + + while (runlength < 255 && (pcre_ctypes[c = *(++ptr)] & ctype_meta) == 0); + + ptr--; + length += runlength; + continue; + } + } + +length += 4; /* For final KET and END */ + +if (length > 65539) + { + *errorptr = ERR20; + return NULL; + } + +/* Compute the size of data block needed and get it, either from malloc or +externally provided function. Put in the magic number and the options. */ + +size = length + offsetof(real_pcre, code); +re = (real_pcre *)(pcre_malloc)(size); + +if (re == NULL) + { + *errorptr = ERR21; + return NULL; + } + +re->magic_number = MAGIC_NUMBER; +re->options = options; + +/* Set up a starting, non-extracting bracket, then compile the expression. On +error, *errorptr will be set non-NULL, so we don't need to look at the result +of the function here. */ + +ptr = (uschar *)pattern; +code = re->code; +*code = OP_BRA; +bracount = 0; +(void)compile_regex(options, &bracount, &code, &ptr, errorptr); +re->top_bracket = bracount; +re->top_backref = top_backref; + +/* If not reached end of pattern on success, there's an excess bracket. */ + +if (*errorptr == NULL && *ptr != 0) *errorptr = ERR22; + +/* Fill in the terminating state and check for disastrous overflow, but +if debugging, leave the test till after things are printed out. */ + +*code++ = OP_END; + +#ifndef DEBUG +if (code - re->code > length) *errorptr = ERR23; +#endif + +/* Failed to compile */ + +if (*errorptr != NULL) + { + (pcre_free)(re); + PCRE_ERROR_RETURN: + *erroroffset = ptr - (uschar *)pattern; + return NULL; + } + +/* If the anchored option was not passed, set flag if we can determine that it +is anchored by virtue of ^ characters or \A or anything else. Otherwise, see if +we can determine what the first character has to be, because that speeds up +unanchored matches no end. In the case of multiline matches, an alternative is +to set the PCRE_STARTLINE flag if all branches start with ^. */ + +if ((options & PCRE_ANCHORED) == 0) + { + if (is_anchored(re->code, (options & PCRE_MULTILINE) != 0)) + re->options |= PCRE_ANCHORED; + else + { + int c = find_firstchar(re->code); + if (c >= 0) + { + re->first_char = c; + re->options |= PCRE_FIRSTSET; + } + else if (is_startline(re->code)) + re->options |= PCRE_STARTLINE; + } + } + +/* Print out the compiled data for debugging */ + +#ifdef DEBUG + +printf("Length = %d top_bracket = %d top_backref=%d\n", + length, re->top_bracket, re->top_backref); + +if (re->options != 0) + { + printf("%s%s%s%s%s%s%s\n", + ((re->options & PCRE_ANCHORED) != 0)? "anchored " : "", + ((re->options & PCRE_CASELESS) != 0)? "caseless " : "", + ((re->options & PCRE_EXTENDED) != 0)? "extended " : "", + ((re->options & PCRE_MULTILINE) != 0)? "multiline " : "", + ((re->options & PCRE_DOTALL) != 0)? "dotall " : "", + ((re->options & PCRE_DOLLAR_ENDONLY) != 0)? "endonly " : "", + ((re->options & PCRE_EXTRA) != 0)? "extra " : ""); + } + +if ((re->options & PCRE_FIRSTSET) != 0) + { + if (isprint(re->first_char)) printf("First char = %c\n", re->first_char); + else printf("First char = \\x%02x\n", re->first_char); + } + +code_end = code; +code_base = code = re->code; + +while (code < code_end) + { + int charlength; + + printf("%3d ", code - code_base); + + if (*code >= OP_BRA) + { + printf("%3d Bra %d", (code[1] << 8) + code[2], *code - OP_BRA); + code += 2; + } + + else switch(*code) + { + case OP_CHARS: + charlength = *(++code); + printf("%3d ", charlength); + while (charlength-- > 0) + if (isprint(c = *(++code))) printf("%c", c); else printf("\\x%02x", c); + break; + + case OP_KETRMAX: + case OP_KETRMIN: + case OP_ALT: + case OP_KET: + case OP_ASSERT: + case OP_ASSERT_NOT: + case OP_ONCE: + printf("%3d %s", (code[1] << 8) + code[2], OP_names[*code]); + code += 2; + break; + + case OP_STAR: + case OP_MINSTAR: + case OP_PLUS: + case OP_MINPLUS: + case OP_QUERY: + case OP_MINQUERY: + case OP_TYPESTAR: + case OP_TYPEMINSTAR: + case OP_TYPEPLUS: + case OP_TYPEMINPLUS: + case OP_TYPEQUERY: + case OP_TYPEMINQUERY: + if (*code >= OP_TYPESTAR) + printf(" %s", OP_names[code[1]]); + else if (isprint(c = code[1])) printf(" %c", c); + else printf(" \\x%02x", c); + printf("%s", OP_names[*code++]); + break; + + case OP_EXACT: + case OP_UPTO: + case OP_MINUPTO: + if (isprint(c = code[3])) printf(" %c{", c); + else printf(" \\x%02x{", c); + if (*code != OP_EXACT) printf(","); + printf("%d}", (code[1] << 8) + code[2]); + if (*code == OP_MINUPTO) printf("?"); + code += 3; + break; + + case OP_TYPEEXACT: + case OP_TYPEUPTO: + case OP_TYPEMINUPTO: + printf(" %s{", OP_names[code[3]]); + if (*code != OP_TYPEEXACT) printf(","); + printf("%d}", (code[1] << 8) + code[2]); + if (*code == OP_TYPEMINUPTO) printf("?"); + code += 3; + break; + + case OP_NOT: + if (isprint(c = *(++code))) printf(" [^%c]", c); + else printf(" [^\\x%02x]", c); + break; + + case OP_NOTSTAR: + case OP_NOTMINSTAR: + case OP_NOTPLUS: + case OP_NOTMINPLUS: + case OP_NOTQUERY: + case OP_NOTMINQUERY: + if (isprint(c = code[1])) printf(" [^%c]", c); + else printf(" [^\\x%02x]", c); + printf("%s", OP_names[*code++]); + break; + + case OP_NOTEXACT: + case OP_NOTUPTO: + case OP_NOTMINUPTO: + if (isprint(c = code[3])) printf(" [^%c]{", c); + else printf(" [^\\x%02x]{", c); + if (*code != OP_NOTEXACT) printf(","); + printf("%d}", (code[1] << 8) + code[2]); + if (*code == OP_NOTMINUPTO) printf("?"); + code += 3; + break; + + case OP_REF: + printf(" \\%d", *(++code)); + break; + + case OP_CLASS: + { + int i, min, max; + + code++; + printf(" ["); + + for (i = 0; i < 256; i++) + { + if ((code[i/8] & (1 << (i&7))) != 0) + { + int j; + for (j = i+1; j < 256; j++) + if ((code[j/8] & (1 << (j&7))) == 0) break; + if (i == '-' || i == ']') printf("\\"); + if (isprint(i)) printf("%c", i); else printf("\\x%02x", i); + if (--j > i) + { + printf("-"); + if (j == '-' || j == ']') printf("\\"); + if (isprint(j)) printf("%c", j); else printf("\\x%02x", j); + } + i = j; + } + } + printf("]"); + code += 32; + + switch(*code) + { + case OP_CRSTAR: + case OP_CRMINSTAR: + case OP_CRPLUS: + case OP_CRMINPLUS: + case OP_CRQUERY: + case OP_CRMINQUERY: + printf("%s", OP_names[*code]); + break; + + case OP_CRRANGE: + case OP_CRMINRANGE: + min = (code[1] << 8) + code[2]; + max = (code[3] << 8) + code[4]; + if (max == 0) printf("{%d,}", min); + else printf("{%d,%d}", min, max); + if (*code == OP_CRMINRANGE) printf("?"); + code += 4; + break; + + default: + code--; + } + } + break; + + /* Anything else is just a one-node item */ + + default: + printf(" %s", OP_names[*code]); + break; + } + + code++; + printf("\n"); + } +printf("------------------------------------------------------------------\n"); + +/* This check is done here in the debugging case so that the code that +was compiled can be seen. */ + +if (code - re->code > length) + { + *errorptr = ERR23; + (pcre_free)(re); + *erroroffset = ptr - (uschar *)pattern; + return NULL; + } +#endif + +return (pcre *)re; +} + + + +/************************************************* +* Match a character type * +*************************************************/ + +/* Not used in all the places it might be as it's sometimes faster +to put the code inline. + +Arguments: + type the character type + c the character + dotall the dotall flag + +Returns: TRUE if character is of the type +*/ + +static BOOL +match_type(int type, int c, BOOL dotall) +{ + +#ifdef DEBUG +if (isprint(c)) printf("matching subject %c against ", c); + else printf("matching subject \\x%02x against ", c); +printf("%s\n", OP_names[type]); +#endif + +switch(type) + { + case OP_ANY: return dotall || c != '\n'; + case OP_NOT_DIGIT: return (pcre_ctypes[c] & ctype_digit) == 0; + case OP_DIGIT: return (pcre_ctypes[c] & ctype_digit) != 0; + case OP_NOT_WHITESPACE: return (pcre_ctypes[c] & ctype_space) == 0; + case OP_WHITESPACE: return (pcre_ctypes[c] & ctype_space) != 0; + case OP_NOT_WORDCHAR: return (pcre_ctypes[c] & ctype_word) == 0; + case OP_WORDCHAR: return (pcre_ctypes[c] & ctype_word) != 0; + } +return FALSE; +} + + + +/************************************************* +* Match a back-reference * +*************************************************/ + +/* If a back reference hasn't been set, the match fails. + +Arguments: + number reference number + eptr points into the subject + length length to be matched + md points to match data block + +Returns: TRUE if matched +*/ + +static BOOL +match_ref(int number, register uschar *eptr, int length, match_data *md) +{ +uschar *p = md->start_subject + md->offset_vector[number]; + +#ifdef DEBUG +if (eptr >= md->end_subject) + printf("matching subject <null>"); +else + { + printf("matching subject "); + pchars(eptr, length, TRUE, md); + } +printf(" against backref "); +pchars(p, length, FALSE, md); +printf("\n"); +#endif + +/* Always fail if not enough characters left */ + +if (length > md->end_subject - p) return FALSE; + +/* Separate the caselesss case for speed */ + +if (md->caseless) + { while (length-- > 0) if (pcre_lcc[*p++] != pcre_lcc[*eptr++]) return FALSE; } +else + { while (length-- > 0) if (*p++ != *eptr++) return FALSE; } + +return TRUE; +} + + + +/************************************************* +* Match from current position * +*************************************************/ + +/* On entry ecode points to the first opcode, and eptr to the first character. + +Arguments: + eptr pointer in subject + ecode position in code + offset_top current top pointer + md pointer to "static" info for the match + +Returns: TRUE if matched +*/ + +static BOOL +match(register uschar *eptr, register uschar *ecode, int offset_top, + match_data *md) +{ +for (;;) + { + int min, max, ctype; + register int i; + register int c; + BOOL minimize; + + /* Opening bracket. Check the alternative branches in turn, failing if none + match. We have to set the start offset if required and there is space + in the offset vector so that it is available for subsequent back references + if the bracket matches. However, if the bracket fails, we must put back the + previous value of both offsets in case they were set by a previous copy of + the same bracket. Don't worry about setting the flag for the error case here; + that is handled in the code for KET. */ + + if ((int)*ecode >= OP_BRA) + { + int number = (*ecode - OP_BRA) << 1; + int save_offset1, save_offset2; + + #ifdef DEBUG + printf("start bracket %d\n", number/2); + #endif + + if (number > 0 && number < md->offset_end) + { + save_offset1 = md->offset_vector[number]; + save_offset2 = md->offset_vector[number+1]; + md->offset_vector[number] = eptr - md->start_subject; + + #ifdef DEBUG + printf("saving %d %d\n", save_offset1, save_offset2); + #endif + } + + /* Recurse for all the alternatives. */ + + do + { + if (match(eptr, ecode+3, offset_top, md)) return TRUE; + ecode += (ecode[1] << 8) + ecode[2]; + } + while (*ecode == OP_ALT); + + #ifdef DEBUG + printf("bracket %d failed\n", number/2); + #endif + + if (number > 0 && number < md->offset_end) + { + md->offset_vector[number] = save_offset1; + md->offset_vector[number+1] = save_offset2; + } + + return FALSE; + } + + /* Other types of node can be handled by a switch */ + + switch(*ecode) + { + case OP_END: + md->end_match_ptr = eptr; /* Record where we ended */ + md->end_offset_top = offset_top; /* and how many extracts were taken */ + return TRUE; + + /* The equivalent of Prolog's "cut" - if the rest doesn't match, the + whole thing doesn't match, so we have to get out via a longjmp(). */ + + case OP_CUT: + if (match(eptr, ecode+1, offset_top, md)) return TRUE; + longjmp(md->fail_env, 1); + + /* Assertion brackets. Check the alternative branches in turn - the + matching won't pass the KET for an assertion. If any one branch matches, + the assertion is true. */ + + case OP_ASSERT: + do + { + if (match(eptr, ecode+3, offset_top, md)) break; + ecode += (ecode[1] << 8) + ecode[2]; + } + while (*ecode == OP_ALT); + if (*ecode == OP_KET) return FALSE; + + /* Continue from after the assertion, updating the offsets high water + mark, since extracts may have been taken during the assertion. */ + + do ecode += (ecode[1] << 8) + ecode[2]; while (*ecode == OP_ALT); + ecode += 3; + offset_top = md->end_offset_top; + continue; + + /* Negative assertion: all branches must fail to match */ + + case OP_ASSERT_NOT: + do + { + if (match(eptr, ecode+3, offset_top, md)) return FALSE; + ecode += (ecode[1] << 8) + ecode[2]; + } + while (*ecode == OP_ALT); + ecode += 3; + continue; + + /* "Once" brackets are like assertion brackets except that after a match, + the point in the subject string is not moved back. Thus there can never be + a back into the brackets. Check the alternative branches in turn - the + matching won't pass the KET for this kind of subpattern. If any one branch + matches, we carry on, leaving the subject pointer. */ + + case OP_ONCE: + do + { + if (match(eptr, ecode+3, offset_top, md)) break; + ecode += (ecode[1] << 8) + ecode[2]; + } + while (*ecode == OP_ALT); + if (*ecode == OP_KET) return FALSE; + + /* Continue as from after the assertion, updating the offsets high water + mark, since extracts may have been taken. */ + + do ecode += (ecode[1] << 8) + ecode[2]; while (*ecode == OP_ALT); + ecode += 3; + offset_top = md->end_offset_top; + eptr = md->end_match_ptr; + continue; + + /* An alternation is the end of a branch; scan along to find the end of the + bracketed group and go to there. */ + + case OP_ALT: + do ecode += (ecode[1] << 8) + ecode[2]; while (*ecode == OP_ALT); + break; + + /* BRAZERO and BRAMINZERO occur just before a bracket group, indicating + that it may occur zero times. It may repeat infinitely, or not at all - + i.e. it could be ()* or ()? in the pattern. Brackets with fixed upper + repeat limits are compiled as a number of copies, with the optional ones + preceded by BRAZERO or BRAMINZERO. */ + + case OP_BRAZERO: + { + uschar *next = ecode+1; + if (match(eptr, next, offset_top, md)) return TRUE; + do next += (next[1] << 8) + next[2]; while (*next == OP_ALT); + ecode = next + 3; + } + break; + + case OP_BRAMINZERO: + { + uschar *next = ecode+1; + do next += (next[1] << 8) + next[2]; while (*next == OP_ALT); + if (match(eptr, next+3, offset_top, md)) return TRUE; + ecode++; + } + break;; + + /* End of a group, repeated or non-repeating. If we are at the end of + an assertion "group", stop matching and return TRUE, but record the + current high water mark for use by positive assertions. */ + + case OP_KET: + case OP_KETRMIN: + case OP_KETRMAX: + { + int number; + uschar *prev = ecode - (ecode[1] << 8) - ecode[2]; + + if (*prev == OP_ASSERT || *prev == OP_ASSERT_NOT || *prev == OP_ONCE) + { + md->end_match_ptr = eptr; /* For ONCE */ + md->end_offset_top = offset_top; + return TRUE; + } + + /* In all other cases we have to check the group number back at the + start and if necessary complete handling an extraction by setting the + final offset and bumping the high water mark. */ + + number = (*prev - OP_BRA) << 1; + + #ifdef DEBUG + printf("end bracket %d\n", number/2); + #endif + + if (number > 0) + { + if (number >= md->offset_end) md->offset_overflow = TRUE; else + { + md->offset_vector[number+1] = eptr - md->start_subject; + if (offset_top <= number) offset_top = number + 2; + } + } + + /* For a non-repeating ket, just advance to the next node and continue at + this level. */ + + if (*ecode == OP_KET) + { + ecode += 3; + break; + } + + /* The repeating kets try the rest of the pattern or restart from the + preceding bracket, in the appropriate order. */ + + if (*ecode == OP_KETRMIN) + { + if (match(eptr, ecode+3, offset_top, md) || + match(eptr, prev, offset_top, md)) return TRUE; + } + else /* OP_KETRMAX */ + { + if (match(eptr, prev, offset_top, md) || + match(eptr, ecode+3, offset_top, md)) return TRUE; + } + } + return FALSE; + + /* Start of subject unless notbol, or after internal newline if multiline */ + + case OP_CIRC: + if (md->notbol && eptr == md->start_subject) return FALSE; + if (md->multiline) + { + if (eptr != md->start_subject && eptr[-1] != '\n') return FALSE; + ecode++; + break; + } + /* ... else fall through */ + + /* Start of subject assertion */ + + case OP_SOD: + if (eptr != md->start_subject) return FALSE; + ecode++; + break; + + /* Assert before internal newline if multiline, or before + a terminating newline unless endonly is set, else end of subject unless + noteol is set. */ + + case OP_DOLL: + if (md->noteol && eptr >= md->end_subject) return FALSE; + if (md->multiline) + { + if (eptr < md->end_subject && *eptr != '\n') return FALSE; + ecode++; + break; + } + else if (!md->endonly) + { + if (eptr < md->end_subject - 1 || + (eptr == md->end_subject - 1 && *eptr != '\n')) return FALSE; + ecode++; + break; + } + /* ... else fall through */ + + /* End of subject assertion */ + + case OP_EOD: + if (eptr < md->end_subject) return FALSE; + ecode++; + break; + + /* Word boundary assertions */ + + case OP_NOT_WORD_BOUNDARY: + case OP_WORD_BOUNDARY: + { + BOOL prev_is_word = (eptr != md->start_subject) && + ((pcre_ctypes[eptr[-1]] & ctype_word) != 0); + BOOL cur_is_word = (eptr < md->end_subject) && + ((pcre_ctypes[*eptr] & ctype_word) != 0); + if ((*ecode++ == OP_WORD_BOUNDARY)? + cur_is_word == prev_is_word : cur_is_word != prev_is_word) + return FALSE; + } + break; + + /* Match a single character type; inline for speed */ + + case OP_ANY: + if (!md->dotall && eptr < md->end_subject && *eptr == '\n') return FALSE; + if (eptr++ >= md->end_subject) return FALSE; + ecode++; + break; + + case OP_NOT_DIGIT: + if (eptr >= md->end_subject || (pcre_ctypes[*eptr++] & ctype_digit) != 0) + return FALSE; + ecode++; + break; + + case OP_DIGIT: + if (eptr >= md->end_subject || (pcre_ctypes[*eptr++] & ctype_digit) == 0) + return FALSE; + ecode++; + break; + + case OP_NOT_WHITESPACE: + if (eptr >= md->end_subject || (pcre_ctypes[*eptr++] & ctype_space) != 0) + return FALSE; + ecode++; + break; + + case OP_WHITESPACE: + if (eptr >= md->end_subject || (pcre_ctypes[*eptr++] & ctype_space) == 0) + return FALSE; + ecode++; + break; + + case OP_NOT_WORDCHAR: + if (eptr >= md->end_subject || (pcre_ctypes[*eptr++] & ctype_word) != 0) + return FALSE; + ecode++; + break; + + case OP_WORDCHAR: + if (eptr >= md->end_subject || (pcre_ctypes[*eptr++] & ctype_word) == 0) + return FALSE; + ecode++; + break; + + /* Match a back reference, possibly repeatedly. Look past the end of the + item to see if there is repeat information following. The code is similar + to that for character classes, but repeated for efficiency. Then obey + similar code to character type repeats - written out again for speed. + However, if the referenced string is the empty string, always treat + it as matched, any number of times (otherwise there could be infinite + loops). */ + + case OP_REF: + { + int length; + int number = ecode[1] << 1; /* Doubled reference number */ + ecode += 2; /* Advance past the item */ + + if (number >= offset_top || md->offset_vector[number] < 0) + { + md->errorcode = PCRE_ERROR_BADREF; + return FALSE; + } + + length = md->offset_vector[number+1] - md->offset_vector[number]; + + switch (*ecode) + { + case OP_CRSTAR: + case OP_CRMINSTAR: + case OP_CRPLUS: + case OP_CRMINPLUS: + case OP_CRQUERY: + case OP_CRMINQUERY: + c = *ecode++ - OP_CRSTAR; + minimize = (c & 1) != 0; + min = rep_min[c]; /* Pick up values from tables; */ + max = rep_max[c]; /* zero for max => infinity */ + if (max == 0) max = INT_MAX; + break; + + case OP_CRRANGE: + case OP_CRMINRANGE: + minimize = (*ecode == OP_CRMINRANGE); + min = (ecode[1] << 8) + ecode[2]; + max = (ecode[3] << 8) + ecode[4]; + if (max == 0) max = INT_MAX; + ecode += 5; + break; + + default: /* No repeat follows */ + if (!match_ref(number, eptr, length, md)) return FALSE; + eptr += length; + continue; /* With the main loop */ + } + + /* If the length of the reference is zero, just continue with the + main loop. */ + + if (length == 0) continue; + + /* First, ensure the minimum number of matches are present. We get back + the length of the reference string explicitly rather than passing the + address of eptr, so that eptr can be a register variable. */ + + for (i = 1; i <= min; i++) + { + if (!match_ref(number, eptr, length, md)) return FALSE; + eptr += length; + } + + /* If min = max, continue at the same level without recursion. + They are not both allowed to be zero. */ + + if (min == max) continue; + + /* If minimizing, keep trying and advancing the pointer */ + + if (minimize) + { + for (i = min;; i++) + { + if (match(eptr, ecode, offset_top, md)) return TRUE; + if (i >= max || !match_ref(number, eptr, length, md)) + return FALSE; + eptr += length; + } + /* Control never gets here */ + } + + /* If maximizing, find the longest string and work backwards */ + + else + { + uschar *pp = eptr; + for (i = min; i < max; i++) + { + if (!match_ref(number, eptr, length, md)) break; + eptr += length; + } + while (eptr >= pp) + { + if (match(eptr, ecode, offset_top, md)) return TRUE; + eptr -= length; + } + return FALSE; + } + } + /* Control never gets here */ + + /* Match a character class, possibly repeatedly. Look past the end of the + item to see if there is repeat information following. Then obey similar + code to character type repeats - written out again for speed. If caseless + matching was set at runtime but not at compile time, we have to check both + versions of a character. */ + + case OP_CLASS: + { + uschar *data = ecode + 1; /* Save for matching */ + ecode += 33; /* Advance past the item */ + + switch (*ecode) + { + case OP_CRSTAR: + case OP_CRMINSTAR: + case OP_CRPLUS: + case OP_CRMINPLUS: + case OP_CRQUERY: + case OP_CRMINQUERY: + c = *ecode++ - OP_CRSTAR; + minimize = (c & 1) != 0; + min = rep_min[c]; /* Pick up values from tables; */ + max = rep_max[c]; /* zero for max => infinity */ + if (max == 0) max = INT_MAX; + break; + + case OP_CRRANGE: + case OP_CRMINRANGE: + minimize = (*ecode == OP_CRMINRANGE); + min = (ecode[1] << 8) + ecode[2]; + max = (ecode[3] << 8) + ecode[4]; + if (max == 0) max = INT_MAX; + ecode += 5; + break; + + default: /* No repeat follows */ + if (eptr >= md->end_subject) return FALSE; + c = *eptr++; + if ((data[c/8] & (1 << (c&7))) != 0) continue; /* With main loop */ + if (md->runtime_caseless) + { + c = pcre_fcc[c]; + if ((data[c/8] & (1 << (c&7))) != 0) continue; /* With main loop */ + } + return FALSE; + } + + /* First, ensure the minimum number of matches are present. */ + + for (i = 1; i <= min; i++) + { + if (eptr >= md->end_subject) return FALSE; + c = *eptr++; + if ((data[c/8] & (1 << (c&7))) != 0) continue; + if (md->runtime_caseless) + { + c = pcre_fcc[c]; + if ((data[c/8] & (1 << (c&7))) != 0) continue; + } + return FALSE; + } + + /* If max == min we can continue with the main loop without the + need to recurse. */ + + if (min == max) continue; + + /* If minimizing, keep testing the rest of the expression and advancing + the pointer while it matches the class. */ + + if (minimize) + { + for (i = min;; i++) + { + if (match(eptr, ecode, offset_top, md)) return TRUE; + if (i >= max || eptr >= md->end_subject) return FALSE; + c = *eptr++; + if ((data[c/8] & (1 << (c&7))) != 0) continue; + if (md->runtime_caseless) + { + c = pcre_fcc[c]; + if ((data[c/8] & (1 << (c&7))) != 0) continue; + } + return FALSE; + } + /* Control never gets here */ + } + + /* If maximizing, find the longest possible run, then work backwards. */ + + else + { + uschar *pp = eptr; + for (i = min; i < max; eptr++, i++) + { + if (eptr >= md->end_subject) break; + c = *eptr; + if ((data[c/8] & (1 << (c&7))) != 0) continue; + if (md->runtime_caseless) + { + c = pcre_fcc[c]; + if ((data[c/8] & (1 << (c&7))) != 0) continue; + } + break; + } + + while (eptr >= pp) + if (match(eptr--, ecode, offset_top, md)) return TRUE; + return FALSE; + } + } + /* Control never gets here */ + + /* Match a run of characters */ + + case OP_CHARS: + { + register int length = ecode[1]; + ecode += 2; + + #ifdef DEBUG + if (eptr >= md->end_subject) + printf("matching subject <null> against pattern "); + else + { + printf("matching subject "); + pchars(eptr, length, TRUE, md); + printf(" against pattern "); + } + pchars(ecode, length, FALSE, md); + printf("\n"); + #endif + + if (length > md->end_subject - eptr) return FALSE; + if (md->caseless) + { + while (length-- > 0) if (pcre_lcc[*ecode++] != pcre_lcc[*eptr++]) return FALSE; + } + else + { + while (length-- > 0) if (*ecode++ != *eptr++) return FALSE; + } + } + break; + + /* Match a single character repeatedly; different opcodes share code. */ + + case OP_EXACT: + min = max = (ecode[1] << 8) + ecode[2]; + ecode += 3; + goto REPEATCHAR; + + case OP_UPTO: + case OP_MINUPTO: + min = 0; + max = (ecode[1] << 8) + ecode[2]; + minimize = *ecode == OP_MINUPTO; + ecode += 3; + goto REPEATCHAR; + + case OP_STAR: + case OP_MINSTAR: + case OP_PLUS: + case OP_MINPLUS: + case OP_QUERY: + case OP_MINQUERY: + c = *ecode++ - OP_STAR; + minimize = (c & 1) != 0; + min = rep_min[c]; /* Pick up values from tables; */ + max = rep_max[c]; /* zero for max => infinity */ + if (max == 0) max = INT_MAX; + + /* Common code for all repeated single-character matches. We can give + up quickly if there are fewer than the minimum number of characters left in + the subject. */ + + REPEATCHAR: + if (min > md->end_subject - eptr) return FALSE; + c = *ecode++; + + /* The code is duplicated for the caseless and caseful cases, for speed, + since matching characters is likely to be quite common. First, ensure the + minimum number of matches are present. If min = max, continue at the same + level without recursing. Otherwise, if minimizing, keep trying the rest of + the expression and advancing one matching character if failing, up to the + maximum. Alternatively, if maximizing, find the maximum number of + characters and work backwards. */ + + #ifdef DEBUG + printf("matching %c{%d,%d} against subject %.*s\n", c, min, max, + max, eptr); + #endif + + if (md->caseless) + { + c = pcre_lcc[c]; + for (i = 1; i <= min; i++) if (c != pcre_lcc[*eptr++]) return FALSE; + if (min == max) continue; + if (minimize) + { + for (i = min;; i++) + { + if (match(eptr, ecode, offset_top, md)) return TRUE; + if (i >= max || eptr >= md->end_subject || c != pcre_lcc[*eptr++]) + return FALSE; + } + /* Control never gets here */ + } + else + { + uschar *pp = eptr; + for (i = min; i < max; i++) + { + if (eptr >= md->end_subject || c != pcre_lcc[*eptr]) break; + eptr++; + } + while (eptr >= pp) + if (match(eptr--, ecode, offset_top, md)) return TRUE; + return FALSE; + } + /* Control never gets here */ + } + + /* Caseful comparisons */ + + else + { + for (i = 1; i <= min; i++) if (c != *eptr++) return FALSE; + if (min == max) continue; + if (minimize) + { + for (i = min;; i++) + { + if (match(eptr, ecode, offset_top, md)) return TRUE; + if (i >= max || eptr >= md->end_subject || c != *eptr++) return FALSE; + } + /* Control never gets here */ + } + else + { + uschar *pp = eptr; + for (i = min; i < max; i++) + { + if (eptr >= md->end_subject || c != *eptr) break; + eptr++; + } + while (eptr >= pp) + if (match(eptr--, ecode, offset_top, md)) return TRUE; + return FALSE; + } + } + /* Control never gets here */ + + /* Match a negated single character */ + + case OP_NOT: + if (eptr > md->end_subject) return FALSE; + ecode++; + if (md->caseless) + { + if (pcre_lcc[*ecode++] == pcre_lcc[*eptr++]) return FALSE; + } + else + { + if (*ecode++ == *eptr++) return FALSE; + } + break; + + /* Match a negated single character repeatedly. This is almost a repeat of + the code for a repeated single character, but I haven't found a nice way of + commoning these up that doesn't require a test of the positive/negative + option for each character match. Maybe that wouldn't add very much to the + time taken, but character matching *is* what this is all about... */ + + case OP_NOTEXACT: + min = max = (ecode[1] << 8) + ecode[2]; + ecode += 3; + goto REPEATNOTCHAR; + + case OP_NOTUPTO: + case OP_NOTMINUPTO: + min = 0; + max = (ecode[1] << 8) + ecode[2]; + minimize = *ecode == OP_NOTMINUPTO; + ecode += 3; + goto REPEATNOTCHAR; + + case OP_NOTSTAR: + case OP_NOTMINSTAR: + case OP_NOTPLUS: + case OP_NOTMINPLUS: + case OP_NOTQUERY: + case OP_NOTMINQUERY: + c = *ecode++ - OP_NOTSTAR; + minimize = (c & 1) != 0; + min = rep_min[c]; /* Pick up values from tables; */ + max = rep_max[c]; /* zero for max => infinity */ + if (max == 0) max = INT_MAX; + + /* Common code for all repeated single-character matches. We can give + up quickly if there are fewer than the minimum number of characters left in + the subject. */ + + REPEATNOTCHAR: + if (min > md->end_subject - eptr) return FALSE; + c = *ecode++; + + /* The code is duplicated for the caseless and caseful cases, for speed, + since matching characters is likely to be quite common. First, ensure the + minimum number of matches are present. If min = max, continue at the same + level without recursing. Otherwise, if minimizing, keep trying the rest of + the expression and advancing one matching character if failing, up to the + maximum. Alternatively, if maximizing, find the maximum number of + characters and work backwards. */ + + #ifdef DEBUG + printf("negative matching %c{%d,%d} against subject %.*s\n", c, min, max, + max, eptr); + #endif + + if (md->caseless) + { + c = pcre_lcc[c]; + for (i = 1; i <= min; i++) if (c == pcre_lcc[*eptr++]) return FALSE; + if (min == max) continue; + if (minimize) + { + for (i = min;; i++) + { + if (match(eptr, ecode, offset_top, md)) return TRUE; + if (i >= max || eptr >= md->end_subject || c == pcre_lcc[*eptr++]) + return FALSE; + } + /* Control never gets here */ + } + else + { + uschar *pp = eptr; + for (i = min; i < max; i++) + { + if (eptr >= md->end_subject || c == pcre_lcc[*eptr]) break; + eptr++; + } + while (eptr >= pp) + if (match(eptr--, ecode, offset_top, md)) return TRUE; + return FALSE; + } + /* Control never gets here */ + } + + /* Caseful comparisons */ + + else + { + for (i = 1; i <= min; i++) if (c == *eptr++) return FALSE; + if (min == max) continue; + if (minimize) + { + for (i = min;; i++) + { + if (match(eptr, ecode, offset_top, md)) return TRUE; + if (i >= max || eptr >= md->end_subject || c == *eptr++) return FALSE; + } + /* Control never gets here */ + } + else + { + uschar *pp = eptr; + for (i = min; i < max; i++) + { + if (eptr >= md->end_subject || c == *eptr) break; + eptr++; + } + while (eptr >= pp) + if (match(eptr--, ecode, offset_top, md)) return TRUE; + return FALSE; + } + } + /* Control never gets here */ + + /* Match a single character type repeatedly; several different opcodes + share code. This is very similar to the code for single characters, but we + repeat it in the interests of efficiency. */ + + case OP_TYPEEXACT: + min = max = (ecode[1] << 8) + ecode[2]; + minimize = TRUE; + ecode += 3; + goto REPEATTYPE; + + case OP_TYPEUPTO: + case OP_TYPEMINUPTO: + min = 0; + max = (ecode[1] << 8) + ecode[2]; + minimize = *ecode == OP_TYPEMINUPTO; + ecode += 3; + goto REPEATTYPE; + + case OP_TYPESTAR: + case OP_TYPEMINSTAR: + case OP_TYPEPLUS: + case OP_TYPEMINPLUS: + case OP_TYPEQUERY: + case OP_TYPEMINQUERY: + c = *ecode++ - OP_TYPESTAR; + minimize = (c & 1) != 0; + min = rep_min[c]; /* Pick up values from tables; */ + max = rep_max[c]; /* zero for max => infinity */ + if (max == 0) max = INT_MAX; + + /* Common code for all repeated single character type matches */ + + REPEATTYPE: + ctype = *ecode++; /* Code for the character type */ + + /* First, ensure the minimum number of matches are present. Use inline + code for maximizing the speed, and do the type test once at the start + (i.e. keep it out of the loop). Also test that there are at least the + minimum number of characters before we start. */ + + if (min > md->end_subject - eptr) return FALSE; + if (min > 0) switch(ctype) + { + case OP_ANY: + if (!md->dotall) + { for (i = 1; i <= min; i++) if (*eptr++ == '\n') return FALSE; } + else eptr += min; + break; + + case OP_NOT_DIGIT: + for (i = 1; i <= min; i++) + if ((pcre_ctypes[*eptr++] & ctype_digit) != 0) return FALSE; + break; + + case OP_DIGIT: + for (i = 1; i <= min; i++) + if ((pcre_ctypes[*eptr++] & ctype_digit) == 0) return FALSE; + break; + + case OP_NOT_WHITESPACE: + for (i = 1; i <= min; i++) + if ((pcre_ctypes[*eptr++] & ctype_space) != 0) return FALSE; + break; + + case OP_WHITESPACE: + for (i = 1; i <= min; i++) + if ((pcre_ctypes[*eptr++] & ctype_space) == 0) return FALSE; + break; + + case OP_NOT_WORDCHAR: + for (i = 1; i <= min; i++) if ((pcre_ctypes[*eptr++] & ctype_word) != 0) + return FALSE; + break; + + case OP_WORDCHAR: + for (i = 1; i <= min; i++) if ((pcre_ctypes[*eptr++] & ctype_word) == 0) + return FALSE; + break; + } + + /* If min = max, continue at the same level without recursing */ + + if (min == max) continue; + + /* If minimizing, we have to test the rest of the pattern before each + subsequent match, so inlining isn't much help; just use the function. */ + + if (minimize) + { + for (i = min;; i++) + { + if (match(eptr, ecode, offset_top, md)) return TRUE; + if (i >= max || eptr >= md->end_subject || + !match_type(ctype, *eptr++, md->dotall)) + return FALSE; + } + /* Control never gets here */ + } + + /* If maximizing it is worth using inline code for speed, doing the type + test once at the start (i.e. keep it out of the loop). */ + + else + { + uschar *pp = eptr; + switch(ctype) + { + case OP_ANY: + if (!md->dotall) + { + for (i = min; i < max; i++) + { + if (eptr >= md->end_subject || *eptr == '\n') break; + eptr++; + } + } + else + { + c = max - min; + if (c > md->end_subject - eptr) c = md->end_subject - eptr; + eptr += c; + } + break; + + case OP_NOT_DIGIT: + for (i = min; i < max; i++) + { + if (eptr >= md->end_subject || (pcre_ctypes[*eptr] & ctype_digit) != 0) + break; + eptr++; + } + break; + + case OP_DIGIT: + for (i = min; i < max; i++) + { + if (eptr >= md->end_subject || (pcre_ctypes[*eptr] & ctype_digit) == 0) + break; + eptr++; + } + break; + + case OP_NOT_WHITESPACE: + for (i = min; i < max; i++) + { + if (eptr >= md->end_subject || (pcre_ctypes[*eptr] & ctype_space) != 0) + break; + eptr++; + } + break; + + case OP_WHITESPACE: + for (i = min; i < max; i++) + { + if (eptr >= md->end_subject || (pcre_ctypes[*eptr] & ctype_space) == 0) + break; + eptr++; + } + break; + + case OP_NOT_WORDCHAR: + for (i = min; i < max; i++) + { + if (eptr >= md->end_subject || (pcre_ctypes[*eptr] & ctype_word) != 0) + break; + eptr++; + } + break; + + case OP_WORDCHAR: + for (i = min; i < max; i++) + { + if (eptr >= md->end_subject || (pcre_ctypes[*eptr] & ctype_word) == 0) + break; + eptr++; + } + break; + } + + while (eptr >= pp) + if (match(eptr--, ecode, offset_top, md)) return TRUE; + return FALSE; + } + /* Control never gets here */ + + /* There's been some horrible disaster. */ + + default: + #ifdef DEBUG + printf("Unknown opcode %d\n", *ecode); + #endif + md->errorcode = PCRE_ERROR_UNKNOWN_NODE; + return FALSE; + } + + /* Do not stick any code in here without much thought; it is assumed + that "continue" in the code above comes out to here to repeat the main + loop. */ + + } /* End of main loop */ +/* Control never reaches here */ +} + + + +/************************************************* +* Execute a Regular Expression * +*************************************************/ + +/* This function applies a compiled re to a subject string and picks out +portions of the string if it matches. Two elements in the vector are set for +each substring: the offsets to the start and end of the substring. + +Arguments: + external_re points to the compiled expression + external_extra points to "hints" from pcre_study() or is NULL + subject points to the subject string + length length of subject string (may contain binary zeros) + options option bits + offsets points to a vector of ints to be filled in with offsets + offsetcount the number of elements in the vector + +Returns: > 0 => success; value is the number of elements filled in + = 0 => success, but offsets is not big enough + -1 => failed to match + < -1 => some kind of unexpected problem +*/ + +int +pcre_exec(const pcre *external_re, const pcre_extra *external_extra, + const char *subject, int length, int options, int *offsets, int offsetcount) +{ +int resetcount; +int ocount = offsetcount; +int first_char = -1; +match_data match_block; +uschar *start_bits = NULL; +uschar *start_match = (uschar *)subject; +uschar *end_subject; +real_pcre *re = (real_pcre *)external_re; +real_pcre_extra *extra = (real_pcre_extra *)external_extra; +BOOL anchored = ((re->options | options) & PCRE_ANCHORED) != 0; +BOOL startline = (re->options & PCRE_STARTLINE) != 0; + +if ((options & ~PUBLIC_EXEC_OPTIONS) != 0) return PCRE_ERROR_BADOPTION; + +if (re == NULL || subject == NULL || + (offsets == NULL && offsetcount > 0)) return PCRE_ERROR_NULL; +if (re->magic_number != MAGIC_NUMBER) return PCRE_ERROR_BADMAGIC; + +match_block.start_subject = (uschar *)subject; +match_block.end_subject = match_block.start_subject + length; +end_subject = match_block.end_subject; + +match_block.caseless = ((re->options | options) & PCRE_CASELESS) != 0; +match_block.runtime_caseless = match_block.caseless && + (re->options & PCRE_CASELESS) == 0; + +match_block.multiline = ((re->options | options) & PCRE_MULTILINE) != 0; +match_block.dotall = ((re->options | options) & PCRE_DOTALL) != 0; +match_block.endonly = ((re->options | options) & PCRE_DOLLAR_ENDONLY) != 0; + +match_block.notbol = (options & PCRE_NOTBOL) != 0; +match_block.noteol = (options & PCRE_NOTEOL) != 0; + +match_block.errorcode = PCRE_ERROR_NOMATCH; /* Default error */ + +/* If the expression has got more back references than the offsets supplied can +hold, we get a temporary bit of working store to use during the matching. +Otherwise, we can use the vector supplied, rounding down the size of it to a +multiple of 2. */ + +ocount &= (-2); +if (re->top_backref > 0 && re->top_backref + 1 >= ocount/2) + { + ocount = re->top_backref * 2 + 2; + match_block.offset_vector = (pcre_malloc)(ocount * sizeof(int)); + if (match_block.offset_vector == NULL) return PCRE_ERROR_NOMEMORY; + #ifdef DEBUG + printf("Got memory to hold back references\n"); + #endif + } +else match_block.offset_vector = offsets; + +match_block.offset_end = ocount; +match_block.offset_overflow = FALSE; + +/* Compute the minimum number of offsets that we need to reset each time. Doing +this makes a huge difference to execution time when there aren't many brackets +in the pattern. */ + +resetcount = 2 + re->top_bracket * 2; +if (resetcount > offsetcount) resetcount = ocount; + +/* If MULTILINE is set at exec time but was not set at compile time, and the +anchored flag is set, we must re-check because a setting provoked by ^ in the +pattern is not right in multi-line mode. Calling is_anchored() again here does +the right check, because multiline is now set. If it now yields FALSE, the +expression must have had ^ starting some of its branches. Check to see if +that is true for *all* branches, and if so, set the startline flag. */ + +if (match_block. multiline && anchored && (re->options & PCRE_MULTILINE) == 0 && + !is_anchored(re->code, match_block.multiline)) + { + anchored = FALSE; + if (is_startline(re->code)) startline = TRUE; + } + +/* Set up the first character to match, if available. The first_char value is +never set for an anchored regular expression, but the anchoring may be forced +at run time, so we have to test for anchoring. The first char may be unset for +an unanchored pattern, of course. If there's no first char and the pattern was +studied, the may be a bitmap of possible first characters. However, we can +use this only if the caseless state of the studying was correct. */ + +if (!anchored) + { + if ((re->options & PCRE_FIRSTSET) != 0) + { + first_char = re->first_char; + if (match_block.caseless) first_char = pcre_lcc[first_char]; + } + else + if (!startline && extra != NULL && + (extra->options & PCRE_STUDY_MAPPED) != 0 && + ((extra->options & PCRE_STUDY_CASELESS) != 0) == match_block.caseless) + start_bits = extra->start_bits; + } + +/* Loop for unanchored matches; for anchored regexps the loop runs just once. */ + +do + { + register int *iptr = match_block.offset_vector; + register int *iend = iptr + resetcount; + + /* Reset the maximum number of extractions we might see. */ + + while (iptr < iend) *iptr++ = -1; + + /* Advance to a unique first char if possible */ + + if (first_char >= 0) + { + if (match_block.caseless) + while (start_match < end_subject && pcre_lcc[*start_match] != first_char) + start_match++; + else + while (start_match < end_subject && *start_match != first_char) + start_match++; + } + + /* Or to just after \n for a multiline match if possible */ + + else if (startline) + { + if (start_match > match_block.start_subject) + { + while (start_match < end_subject && start_match[-1] != '\n') + start_match++; + } + } + + /* Or to a non-unique first char */ + + else if (start_bits != NULL) + { + while (start_match < end_subject) + { + register int c = *start_match; + if ((start_bits[c/8] & (1 << (c&7))) == 0) start_match++; else break; + } + } + + #ifdef DEBUG + printf(">>>> Match against: "); + pchars(start_match, end_subject - start_match, TRUE, &match_block); + printf("\n"); + #endif + + /* When a match occurs, substrings will be set for all internal extractions; + we just need to set up the whole thing as substring 0 before returning. If + there were too many extractions, set the return code to zero. In the case + where we had to get some local store to hold offsets for backreferences, copy + those back references that we can. In this case there need not be overflow + if certain parts of the pattern were not used. + + Before starting the match, we have to set up a longjmp() target to enable + the "cut" operation to fail a match completely without backtracking. */ + + if (setjmp(match_block.fail_env) == 0 && + match(start_match, re->code, 2, &match_block)) + { + int rc; + + if (ocount != offsetcount) + { + if (offsetcount >= 4) + { + memcpy(offsets + 2, match_block.offset_vector + 2, + (offsetcount - 2) * sizeof(int)); + #ifdef DEBUG + printf("Copied offsets; freeing temporary memory\n"); + #endif + } + if (match_block.end_offset_top > offsetcount) + match_block.offset_overflow = TRUE; + + #ifdef DEBUG + printf("Freeing temporary memory\n"); + #endif + + (pcre_free)(match_block.offset_vector); + } + + rc = match_block.offset_overflow? 0 : match_block.end_offset_top/2; + + if (match_block.offset_end < 2) rc = 0; else + { + offsets[0] = start_match - match_block.start_subject; + offsets[1] = match_block.end_match_ptr - match_block.start_subject; + } + + #ifdef DEBUG + printf(">>>> returning %d\n", rc); + #endif + return rc; + } + } +while (!anchored && + match_block.errorcode == PCRE_ERROR_NOMATCH && + start_match++ < end_subject); + +#ifdef DEBUG +printf(">>>> returning %d\n", match_block.errorcode); +#endif + +return match_block.errorcode; +} + +/* End of pcre.c */ |