diff options
Diffstat (limited to 'generic/regc_nfa.c')
| -rw-r--r-- | generic/regc_nfa.c | 35 |
1 files changed, 5 insertions, 30 deletions
diff --git a/generic/regc_nfa.c b/generic/regc_nfa.c index 14ee077..8143181 100644 --- a/generic/regc_nfa.c +++ b/generic/regc_nfa.c @@ -575,7 +575,7 @@ struct state *s; static VOID dupnfa(nfa, start, stop, from, to) struct nfa *nfa; -struct state *start; /* duplicate starting here */ +struct state *start; /* duplicate of subNFA starting here */ struct state *stop; /* and stopping here */ struct state *from; /* stringing duplicate from here */ struct state *to; /* to here */ @@ -1161,7 +1161,8 @@ struct nfa *nfa; struct arc *a; struct arc *aa; - /* can the NFA match the empty string? */ + if (nfa->pre->outs == NULL) + return REG_UIMPOSSIBLE; for (a = nfa->pre->outs; a != NULL; a = a->outchain) for (aa = a->to->outs; aa != NULL; aa = aa->outchain) if (aa->to == nfa->post) @@ -1170,29 +1171,6 @@ struct nfa *nfa; } /* - - isempty - is a sub-NFA composed only of EMPTY arcs? - * Somewhat limited implementation, makes assumptions. - ^ static int isempty(struct state *, struct state *); - */ -static int -isempty(begin, end) -struct state *begin; -struct state *end; -{ - struct state *s; - - for (s = begin; s != end; s = s->outs->to) { - if (s->nouts != 1) - return 0; - assert(s->outs != NULL); - if (s->outs->type != EMPTY) - return 0; - } - - return 1; -} - -/* - compact - compact an NFA ^ static VOID compact(struct nfa *, struct cnfa *); */ @@ -1305,19 +1283,16 @@ struct carc *last; /* - freecnfa - free a compacted NFA - ^ static VOID freecnfa(struct cnfa *, int); + ^ static VOID freecnfa(struct cnfa *); */ static VOID -freecnfa(cnfa, dynalloc) +freecnfa(cnfa) struct cnfa *cnfa; -int dynalloc; /* is the cnfa struct itself dynamic? */ { assert(cnfa->nstates != 0); /* not empty already */ cnfa->nstates = 0; FREE(cnfa->states); FREE(cnfa->arcs); - if (dynalloc) - FREE(cnfa); } /* |