diff options
Diffstat (limited to 'src/backend/regex/regexec.c')
| -rw-r--r-- | src/backend/regex/regexec.c | 21 |
1 files changed, 16 insertions, 5 deletions
diff --git a/src/backend/regex/regexec.c b/src/backend/regex/regexec.c index ee16a5ef412..0f14d5ba01e 100644 --- a/src/backend/regex/regexec.c +++ b/src/backend/regex/regexec.c @@ -426,6 +426,7 @@ cfindloop(struct vars * v, close = v->search_start; do { + /* Search with the search RE for match range at/beyond "close" */ MDEBUG(("\ncsearch at %ld\n", LOFF(close))); close = shortest(v, s, close, close, v->stop, &cold, (int *) NULL); if (ISERR()) @@ -434,10 +435,11 @@ cfindloop(struct vars * v, return v->err; } if (close == NULL) - break; /* NOTE BREAK */ + break; /* no more possible match anywhere */ assert(cold != NULL); open = cold; cold = NULL; + /* Search for matches starting between "open" and "close" inclusive */ MDEBUG(("cbetween %ld and %ld\n", LOFF(open), LOFF(close))); for (begin = open; begin <= close; begin++) { @@ -446,6 +448,7 @@ cfindloop(struct vars * v, estop = v->stop; for (;;) { + /* Here we use the top node's detailed RE */ if (shorter) end = shortest(v, d, begin, estart, estop, (chr **) NULL, &hitend); @@ -460,8 +463,9 @@ cfindloop(struct vars * v, if (hitend && cold == NULL) cold = begin; if (end == NULL) - break; /* NOTE BREAK OUT */ + break; /* no match with this begin point, try next */ MDEBUG(("tentative end %ld\n", LOFF(end))); + /* Dissect the potential match to see if it really matches */ zapsubs(v->pmatch, v->nmatch); zapmem(v, v->g->tree); er = cdissect(v, v->g->tree, begin, end); @@ -481,21 +485,28 @@ cfindloop(struct vars * v, *coldp = cold; return er; } - /* try next shorter/longer match with same begin point */ + /* Try next longer/shorter match with same begin point */ if (shorter) { if (end == estop) - break; /* NOTE BREAK OUT */ + break; /* no more, so try next begin point */ estart = end + 1; } else { if (end == begin) - break; /* NOTE BREAK OUT */ + break; /* no more, so try next begin point */ estop = end - 1; } } /* end loop over endpoint positions */ } /* end loop over beginning positions */ + + /* + * If we get here, there is no possible match starting at or before + * "close", so consider matches beyond that. We'll do a fresh search + * with the search RE to find a new promising match range. + */ + close++; } while (close < v->stop); *coldp = cold; |