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| author | Nick Wellnhofer <wellnhofer@aevum.de> | 2023-03-09 05:25:09 +0100 |
|---|---|---|
| committer | Nick Wellnhofer <wellnhofer@aevum.de> | 2023-04-30 22:36:33 +0200 |
| commit | 9f7b114232904a7d0e304bff30ed4b255f34a572 (patch) | |
| tree | 545a36982678624ad3bfde5762289d23a5189695 | |
| parent | 4f49017e37c489397ebc6995fab0fe56a339bd9f (diff) | |
| download | libxml2-9f7b114232904a7d0e304bff30ed4b255f34a572.tar.gz | |
regexp: Fix cycle check in xmlFAReduceEpsilonTransitions
The visited flag must only be reset after the first call to
xmlFAReduceEpsilonTransitions has finished. Visiting states multiple
times could lead to unnecessary processing of duplicate transitions.
Similar to 68eadabd.
| -rw-r--r-- | xmlregexp.c | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/xmlregexp.c b/xmlregexp.c index 5638ddc6..ddae0851 100644 --- a/xmlregexp.c +++ b/xmlregexp.c @@ -1864,7 +1864,32 @@ xmlFAReduceEpsilonTransitions(xmlRegParserCtxtPtr ctxt, int fromnr, } } } +} + +/** + * xmlFAFinishReduceEpsilonTransitions: + * @ctxt: a regexp parser context + * @fromnr: the from state + * @tonr: the to state + * @counter: should that transition be associated to a counted + * + */ +static void +xmlFAFinishReduceEpsilonTransitions(xmlRegParserCtxtPtr ctxt, int tonr) { + int transnr; + xmlRegStatePtr to; + + to = ctxt->states[tonr]; + if ((to->mark == XML_REGEXP_MARK_START) || + (to->mark == XML_REGEXP_MARK_NORMAL)) + return; + to->mark = XML_REGEXP_MARK_NORMAL; + for (transnr = 0;transnr < to->nbTrans;transnr++) { + xmlRegTransPtr t1 = &to->trans[transnr]; + if ((t1->to >= 0) && (t1->atom == NULL)) + xmlFAFinishReduceEpsilonTransitions(ctxt, t1->to); + } } /** @@ -2016,6 +2041,7 @@ xmlFAEliminateEpsilonTransitions(xmlRegParserCtxtPtr ctxt) { state->mark = XML_REGEXP_MARK_START; xmlFAReduceEpsilonTransitions(ctxt, statenr, newto, state->trans[transnr].counter); + xmlFAFinishReduceEpsilonTransitions(ctxt, newto); state->mark = XML_REGEXP_MARK_NORMAL; #ifdef DEBUG_REGEXP_GRAPH } else { |