diff options
Diffstat (limited to 'pcre.c')
| -rw-r--r-- | pcre.c | 157 |
1 files changed, 108 insertions, 49 deletions
@@ -145,6 +145,21 @@ static BOOL compile_regex(int, int, int *, uschar **, const uschar **, const char **, BOOL, int, int *, int *, compile_data *); +/* Structure for building a chain of data that actually lives on the +stack, for holding the values of the subject pointer at the start of each +subpattern, so as to detect when an empty string has been matched by a +subpattern - to break infinite loops. */ + +typedef struct eptrblock { + struct eptrblock *prev; + const uschar *saved_eptr; +} eptrblock; + +/* Flag bits for the match() function */ + +#define match_condassert 0x01 /* Called to check a condition assertion */ +#define match_isgroup 0x02 /* Set if start of bracketed group */ + /************************************************* @@ -855,7 +870,9 @@ for (;; ptr++) if ((cd->ctypes[c] & ctype_space) != 0) continue; if (c == '#') { - while ((c = *(++ptr)) != 0 && c != '\n'); + /* The space before the ; is to avoid a warning on a silly compiler + on the Macintosh. */ + while ((c = *(++ptr)) != 0 && c != '\n') ; continue; } } @@ -1795,7 +1812,9 @@ for (;; ptr++) if ((cd->ctypes[c] & ctype_space) != 0) continue; if (c == '#') { - while ((c = *(++ptr)) != 0 && c != '\n'); + /* The space before the ; is to avoid a warning on a silly compiler + on the Macintosh. */ + while ((c = *(++ptr)) != 0 && c != '\n') ; if (c == 0) break; continue; } @@ -2313,7 +2332,9 @@ while ((c = *(++ptr)) != 0) if ((compile_block.ctypes[c] & ctype_space) != 0) continue; if (c == '#') { - while ((c = *(++ptr)) != 0 && c != '\n'); + /* The space before the ; is to avoid a warning on a silly compiler + on the Macintosh. */ + while ((c = *(++ptr)) != 0 && c != '\n') ; continue; } } @@ -2523,8 +2544,8 @@ while ((c = *(++ptr)) != 0) else /* An assertion must follow */ { ptr++; /* Can treat like ':' as far as spacing is concerned */ - - if (ptr[2] != '?' || strchr("=!<", ptr[3]) == NULL) + if (ptr[2] != '?' || + (ptr[3] != '=' && ptr[3] != '!' && ptr[3] != '<') ) { ptr += 2; /* To get right offset in message */ *errorptr = ERR28; @@ -2737,7 +2758,9 @@ while ((c = *(++ptr)) != 0) if ((compile_block.ctypes[c] & ctype_space) != 0) continue; if (c == '#') { - while ((c = *(++ptr)) != 0 && c != '\n'); + /* The space before the ; is to avoid a warning on a silly compiler + on the Macintosh. */ + while ((c = *(++ptr)) != 0 && c != '\n') ; continue; } } @@ -3195,18 +3218,36 @@ Arguments: offset_top current top pointer md pointer to "static" info for the match ims current /i, /m, and /s options - condassert TRUE if called to check a condition assertion - eptrb eptr at start of last bracket + eptrb pointer to chain of blocks containing eptr at start of + brackets - for testing for empty matches + flags can contain + match_condassert - this is an assertion condition + match_isgroup - this is the start of a bracketed group Returns: TRUE if matched */ static BOOL match(register const uschar *eptr, register const uschar *ecode, - int offset_top, match_data *md, unsigned long int ims, BOOL condassert, - const uschar *eptrb) + int offset_top, match_data *md, unsigned long int ims, eptrblock *eptrb, + int flags) { unsigned long int original_ims = ims; /* Save for resetting on ')' */ +eptrblock newptrb; + +/* At the start of a bracketed group, add the current subject pointer to the +stack of such pointers, to be re-instated at the end of the group when we hit +the closing ket. When match() is called in other circumstances, we don't add to +the stack. */ + +if ((flags & match_isgroup) != 0) + { + newptrb.prev = eptrb; + newptrb.saved_eptr = eptr; + eptrb = &newptrb; + } + +/* Now start processing the operations. */ for (;;) { @@ -3252,7 +3293,8 @@ for (;;) do { - if (match(eptr, ecode+3, offset_top, md, ims, FALSE, eptr)) return TRUE; + if (match(eptr, ecode+3, offset_top, md, ims, eptrb, match_isgroup)) + return TRUE; ecode += (ecode[1] << 8) + ecode[2]; } while (*ecode == OP_ALT); @@ -3278,7 +3320,8 @@ for (;;) DPRINTF(("start bracket 0\n")); do { - if (match(eptr, ecode+3, offset_top, md, ims, FALSE, eptr)) return TRUE; + if (match(eptr, ecode+3, offset_top, md, ims, eptrb, match_isgroup)) + return TRUE; ecode += (ecode[1] << 8) + ecode[2]; } while (*ecode == OP_ALT); @@ -3297,7 +3340,7 @@ for (;;) return match(eptr, ecode + ((offset < offset_top && md->offset_vector[offset] >= 0)? 5 : 3 + (ecode[1] << 8) + ecode[2]), - offset_top, md, ims, FALSE, eptr); + offset_top, md, ims, eptrb, match_isgroup); } /* The condition is an assertion. Call match() to evaluate it - setting @@ -3305,13 +3348,14 @@ for (;;) else { - if (match(eptr, ecode+3, offset_top, md, ims, TRUE, NULL)) + if (match(eptr, ecode+3, offset_top, md, ims, NULL, + match_condassert | match_isgroup)) { ecode += 3 + (ecode[4] << 8) + ecode[5]; while (*ecode == OP_ALT) ecode += (ecode[1] << 8) + ecode[2]; } else ecode += (ecode[1] << 8) + ecode[2]; - return match(eptr, ecode+3, offset_top, md, ims, FALSE, eptr); + return match(eptr, ecode+3, offset_top, md, ims, eptrb, match_isgroup); } /* Control never reaches here */ @@ -3348,7 +3392,7 @@ for (;;) case OP_ASSERTBACK: do { - if (match(eptr, ecode+3, offset_top, md, ims, FALSE, NULL)) break; + if (match(eptr, ecode+3, offset_top, md, ims, NULL, match_isgroup)) break; ecode += (ecode[1] << 8) + ecode[2]; } while (*ecode == OP_ALT); @@ -3356,7 +3400,7 @@ for (;;) /* If checking an assertion for a condition, return TRUE. */ - if (condassert) return TRUE; + if ((flags & match_condassert) != 0) return TRUE; /* Continue from after the assertion, updating the offsets high water mark, since extracts may have been taken during the assertion. */ @@ -3372,12 +3416,14 @@ for (;;) case OP_ASSERTBACK_NOT: do { - if (match(eptr, ecode+3, offset_top, md, ims, FALSE, NULL)) return FALSE; + if (match(eptr, ecode+3, offset_top, md, ims, NULL, match_isgroup)) + return FALSE; ecode += (ecode[1] << 8) + ecode[2]; } while (*ecode == OP_ALT); - if (condassert) return TRUE; + if ((flags & match_condassert) != 0) return TRUE; + ecode += 3; continue; @@ -3423,7 +3469,8 @@ for (;;) for (i = 1; i <= c; i++) save[i] = md->offset_vector[md->offset_end - i]; - rc = match(eptr, md->start_pattern, offset_top, md, ims, FALSE, eptrb); + rc = match(eptr, md->start_pattern, offset_top, md, ims, eptrb, + match_isgroup); for (i = 1; i <= c; i++) md->offset_vector[md->offset_end - i] = save[i]; if (save != stacksave) (pcre_free)(save); @@ -3449,10 +3496,12 @@ for (;;) case OP_ONCE: { const uschar *prev = ecode; + const uschar *saved_eptr = eptr; do { - if (match(eptr, ecode+3, offset_top, md, ims, FALSE, eptr)) break; + if (match(eptr, ecode+3, offset_top, md, ims, eptrb, match_isgroup)) + break; ecode += (ecode[1] << 8) + ecode[2]; } while (*ecode == OP_ALT); @@ -3475,7 +3524,7 @@ for (;;) 5.005. If there is an options reset, it will get obeyed in the normal course of events. */ - if (*ecode == OP_KET || eptr == eptrb) + if (*ecode == OP_KET || eptr == saved_eptr) { ecode += 3; break; @@ -3494,13 +3543,14 @@ for (;;) if (*ecode == OP_KETRMIN) { - if (match(eptr, ecode+3, offset_top, md, ims, FALSE, eptr) || - match(eptr, prev, offset_top, md, ims, FALSE, eptr)) return TRUE; + if (match(eptr, ecode+3, offset_top, md, ims, eptrb, 0) || + match(eptr, prev, offset_top, md, ims, eptrb, match_isgroup)) + return TRUE; } else /* OP_KETRMAX */ { - if (match(eptr, prev, offset_top, md, ims, FALSE, eptr) || - match(eptr, ecode+3, offset_top, md, ims, FALSE, eptr)) return TRUE; + if (match(eptr, prev, offset_top, md, ims, eptrb, match_isgroup) || + match(eptr, ecode+3, offset_top, md, ims, eptrb, 0)) return TRUE; } } return FALSE; @@ -3521,7 +3571,8 @@ for (;;) case OP_BRAZERO: { const uschar *next = ecode+1; - if (match(eptr, next, offset_top, md, ims, FALSE, eptr)) return TRUE; + if (match(eptr, next, offset_top, md, ims, eptrb, match_isgroup)) + return TRUE; do next += (next[1] << 8) + next[2]; while (*next == OP_ALT); ecode = next + 3; } @@ -3531,7 +3582,8 @@ for (;;) { const uschar *next = ecode+1; do next += (next[1] << 8) + next[2]; while (*next == OP_ALT); - if (match(eptr, next+3, offset_top, md, ims, FALSE, eptr)) return TRUE; + if (match(eptr, next+3, offset_top, md, ims, eptrb, match_isgroup)) + return TRUE; ecode++; } break; @@ -3546,6 +3598,9 @@ for (;;) case OP_KETRMAX: { const uschar *prev = ecode - (ecode[1] << 8) - ecode[2]; + const uschar *saved_eptr = eptrb->saved_eptr; + + eptrb = eptrb->prev; /* Back up the stack of bracket start pointers */ if (*prev == OP_ASSERT || *prev == OP_ASSERT_NOT || *prev == OP_ASSERTBACK || *prev == OP_ASSERTBACK_NOT || @@ -3565,7 +3620,10 @@ for (;;) int number = *prev - OP_BRA; int offset = number << 1; - DPRINTF(("end bracket %d\n", number)); +#ifdef DEBUG + printf("end bracket %d", number); + printf("\n"); +#endif if (number > 0) { @@ -3591,7 +3649,7 @@ for (;;) 5.005. If there is an options reset, it will get obeyed in the normal course of events. */ - if (*ecode == OP_KET || eptr == eptrb) + if (*ecode == OP_KET || eptr == saved_eptr) { ecode += 3; break; @@ -3602,13 +3660,14 @@ for (;;) if (*ecode == OP_KETRMIN) { - if (match(eptr, ecode+3, offset_top, md, ims, FALSE, eptr) || - match(eptr, prev, offset_top, md, ims, FALSE, eptr)) return TRUE; + if (match(eptr, ecode+3, offset_top, md, ims, eptrb, 0) || + match(eptr, prev, offset_top, md, ims, eptrb, match_isgroup)) + return TRUE; } else /* OP_KETRMAX */ { - if (match(eptr, prev, offset_top, md, ims, FALSE, eptr) || - match(eptr, ecode+3, offset_top, md, ims, FALSE, eptr)) return TRUE; + if (match(eptr, prev, offset_top, md, ims, eptrb, match_isgroup) || + match(eptr, ecode+3, offset_top, md, ims, eptrb, 0)) return TRUE; } } return FALSE; @@ -3819,7 +3878,7 @@ for (;;) { for (i = min;; i++) { - if (match(eptr, ecode, offset_top, md, ims, FALSE, eptrb)) + if (match(eptr, ecode, offset_top, md, ims, eptrb, 0)) return TRUE; if (i >= max || !match_ref(offset, eptr, length, md, ims)) return FALSE; @@ -3840,7 +3899,7 @@ for (;;) } while (eptr >= pp) { - if (match(eptr, ecode, offset_top, md, ims, FALSE, eptrb)) + if (match(eptr, ecode, offset_top, md, ims, eptrb, 0)) return TRUE; eptr -= length; } @@ -3911,7 +3970,7 @@ for (;;) { for (i = min;; i++) { - if (match(eptr, ecode, offset_top, md, ims, FALSE, eptrb)) + if (match(eptr, ecode, offset_top, md, ims, eptrb, 0)) return TRUE; if (i >= max || eptr >= md->end_subject) return FALSE; c = *eptr++; @@ -3935,7 +3994,7 @@ for (;;) } while (eptr >= pp) - if (match(eptr--, ecode, offset_top, md, ims, FALSE, eptrb)) + if (match(eptr--, ecode, offset_top, md, ims, eptrb, 0)) return TRUE; return FALSE; } @@ -4032,7 +4091,7 @@ for (;;) { for (i = min;; i++) { - if (match(eptr, ecode, offset_top, md, ims, FALSE, eptrb)) + if (match(eptr, ecode, offset_top, md, ims, eptrb, 0)) return TRUE; if (i >= max || eptr >= md->end_subject || c != md->lcc[*eptr++]) @@ -4049,7 +4108,7 @@ for (;;) eptr++; } while (eptr >= pp) - if (match(eptr--, ecode, offset_top, md, ims, FALSE, eptrb)) + if (match(eptr--, ecode, offset_top, md, ims, eptrb, 0)) return TRUE; return FALSE; } @@ -4066,7 +4125,7 @@ for (;;) { for (i = min;; i++) { - if (match(eptr, ecode, offset_top, md, ims, FALSE, eptrb)) + if (match(eptr, ecode, offset_top, md, ims, eptrb, 0)) return TRUE; if (i >= max || eptr >= md->end_subject || c != *eptr++) return FALSE; } @@ -4081,7 +4140,7 @@ for (;;) eptr++; } while (eptr >= pp) - if (match(eptr--, ecode, offset_top, md, ims, FALSE, eptrb)) + if (match(eptr--, ecode, offset_top, md, ims, eptrb, 0)) return TRUE; return FALSE; } @@ -4163,7 +4222,7 @@ for (;;) { for (i = min;; i++) { - if (match(eptr, ecode, offset_top, md, ims, FALSE, eptrb)) + if (match(eptr, ecode, offset_top, md, ims, eptrb, 0)) return TRUE; if (i >= max || eptr >= md->end_subject || c == md->lcc[*eptr++]) @@ -4180,7 +4239,7 @@ for (;;) eptr++; } while (eptr >= pp) - if (match(eptr--, ecode, offset_top, md, ims, FALSE, eptrb)) + if (match(eptr--, ecode, offset_top, md, ims, eptrb, 0)) return TRUE; return FALSE; } @@ -4197,7 +4256,7 @@ for (;;) { for (i = min;; i++) { - if (match(eptr, ecode, offset_top, md, ims, FALSE, eptrb)) + if (match(eptr, ecode, offset_top, md, ims, eptrb, 0)) return TRUE; if (i >= max || eptr >= md->end_subject || c == *eptr++) return FALSE; } @@ -4212,7 +4271,7 @@ for (;;) eptr++; } while (eptr >= pp) - if (match(eptr--, ecode, offset_top, md, ims, FALSE, eptrb)) + if (match(eptr--, ecode, offset_top, md, ims, eptrb, 0)) return TRUE; return FALSE; } @@ -4312,7 +4371,7 @@ for (;;) { for (i = min;; i++) { - if (match(eptr, ecode, offset_top, md, ims, FALSE, eptrb)) return TRUE; + if (match(eptr, ecode, offset_top, md, ims, eptrb, 0)) return TRUE; if (i >= max || eptr >= md->end_subject) return FALSE; c = *eptr++; @@ -4431,7 +4490,7 @@ for (;;) } while (eptr >= pp) - if (match(eptr--, ecode, offset_top, md, ims, FALSE, eptrb)) + if (match(eptr--, ecode, offset_top, md, ims, eptrb, 0)) return TRUE; return FALSE; } @@ -4717,7 +4776,7 @@ do if certain parts of the pattern were not used. */ match_block.start_match = start_match; - if (!match(start_match, re->code, 2, &match_block, ims, FALSE, start_match)) + if (!match(start_match, re->code, 2, &match_block, ims, NULL, match_isgroup)) continue; /* Copy the offset information from temporary store if necessary */ |