diff options
Diffstat (limited to 'Src/pattern.c')
| -rw-r--r-- | Src/pattern.c | 23 |
1 files changed, 21 insertions, 2 deletions
diff --git a/Src/pattern.c b/Src/pattern.c index 3edda1772..1e0ae88d9 100644 --- a/Src/pattern.c +++ b/Src/pattern.c @@ -2987,14 +2987,15 @@ patmatch(Upat prog) case P_EXCSYNC: /* See the P_EXCLUDE code below for where syncptr comes from */ { - unsigned char *syncptr; + unsigned char *syncstart, *syncptr, *ptr; Upat after; after = P_OPERAND(scan); DPUTS(!P_ISEXCLUDE(after), "BUG: EXCSYNC not followed by EXCLUDE."); DPUTS(!P_OPERAND(after)->p, "BUG: EXCSYNC not handled by EXCLUDE"); - syncptr = P_OPERAND(after)->p + (patinput - patinstart); + syncstart = P_OPERAND(after)->p; + syncptr = syncstart + (patinput - patinstart); /* * If we already matched from here, this time we fail. * See WBRANCH code for story about error count. @@ -3009,6 +3010,23 @@ patmatch(Upat prog) * failed anyway. */ *syncptr = errsfound + 1; + /* + * Because of backtracking, any match before this point + * can't apply to the current branch we're on so is now + * a failure --- this can happen if, on a previous + * branch, we initially marked a success before failing + * on a later part of the pattern after marking up the + * P_EXCSYNC (even an end anchor will have this effect). + * To make sure we record the current match point + * correctly, mark those down now. + * + * This might have side effects on the efficiency of + * pathological cases involving nested branches. To + * fix that we'd probably need to record matches on + * different branches separately. + */ + for (ptr = syncstart; ptr < syncptr; ++ptr) + *ptr = 0; } break; case P_EXCEND: @@ -3673,6 +3691,7 @@ mb_patmatchrange(char *range, wchar_t ch, int zmb_ind, wint_t *indptr, int *mtp) return 1; break; case PP_IDENT: + /* Could use INAMESPC here? */ if (wcsitype(ch, IIDENT)) return 1; break; |