March 2007 - Libsmi - lists.ibr.cs.tu-bs.de

libsmi reporting parse error, expecting '$'
by Juergen Schoenwaelder 21 Mar '07

21 Mar '07

Folks, I was getting this error IF-MIB:1: parse error, expecting `$' on several differnt platforms and it finally turned out to be an issue with bison/flex. I do not know the details, but I do know that the combination bison 1.875d and flex 2.5.31 does not work while the combination bison 2.1 and flex 2.5.4 seems to be fine. So if someone runs into similar trouble, make sure you upgrade your build tools... /js -- Juergen Schoenwaelder International University Bremen <http://www.eecs.iu-bremen.de/> P.O. Box 750 561, 28725 Bremen, Germany

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Perl dumper creates malformed code for malformed IMPORTS
by Bill Fenner 21 Mar '07

21 Mar '07

I know, I know, GIGO, and why am I using -k? (I am using -k because some of the problems that force using -k will still produce perfectly useful output. I suspect fixing this would require re-evaluating the severity of quite a few errors; using -k is way easier.)) I have several poorly-extracted MIBs where an I-D header ended up in the middle of the IMPORTS clause, causing a syntax error and several smiImport data structures with a null module ID. Since lastModule==NULL was used as a flag for "did I ever print anything", and strcmp has unpredictable handling for being passed NULL, I just skipped the inside of the loop if the current import's module is NULL. Diff follows. Bill --- dump-perl.c (revision 6635) +++ dump-perl.c (working copy) @@ -617,11 +617,12 @@ for (i = 0, smiImport = smiGetFirstImport(smiModule); smiImport; i++, - lastModule = smiImport->module, smiImport = smiGetNextImport(smiImport)) { if (i == 0) { fprintSegment(f, INDENT, "\"imports\" => [\n", 0); } + if (smiImport->module == NULL) + continue; if ( lastModule == NULL || strcmp(lastModule, smiImport->module)) { if ( lastModule ) { @@ -636,6 +637,7 @@ } fprintSegment(f, 4 * INDENT, "", 0); fprint(f, "\"%s\",\n", smiImport->name); + lastModule = smiImport->module; } if (lastModule) { fprintSegment(f, 3 * INDENT, "],\n", 0);

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Perl dumper truncates DEFVALs with lots of BITS, causing perl syntax errors
by Bill Fenner 13 Mar '07

13 Mar '07

There are two fixed-size buffers in this code path: - getValueString's s[100]. This one is gaily overflowed, with sprintf(&s[strlen(s)], ...) - fprint's s[200]. This one is not overflowed, but this overflow causes the syntax error, since fprint(f, "\"%s\"", getValueString(smiValue, smiType)); loses the trailing quote. My workaround was to change them to s[500] and s[1000], respectively. A more robust workaround might be to output the trailing quote with a different fprint() call, so that a too-long value creates a valid perl program with invalid data. (I don't know if that's better or worse.) If vasprintf() is available, fprint could use that to avoid a fixed-length buffer. I don't have any suggestions for getValueString's fixed-length buffer. A good test case is POLICY-BASED-MANAGEMENT-MIB (RFC 4011)'s pmSchedDay. Bill

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