Avoid core dump on empty thesaurus dictionary.

Per report from Robert Gravsjö.

diff --git a/src/backend/tsearch/dict_thesaurus.c b/src/backend/tsearch/dict_thesaurus.c
index 4befc72989d04be853eeb3238a7bb5f35af509c6..cfa8be8d12d7139c768fb271770b68c93ea85f46 100644 (file)
--- a/src/backend/tsearch/dict_thesaurus.c
+++ b/src/backend/tsearch/dict_thesaurus.c
@@ -7,7 +7,7 @@
  *
  *
  * IDENTIFICATION
- *       $PostgreSQL: pgsql/src/backend/tsearch/dict_thesaurus.c,v 1.14 2009/07/16 06:33:44 petere Exp $
+ *       $PostgreSQL: pgsql/src/backend/tsearch/dict_thesaurus.c,v 1.15 2009/11/30 16:38:31 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -57,8 +57,8 @@ typedef struct
 
        /* Array to search lexeme by exact match */
        TheLexeme  *wrds;
-       int                     nwrds;
-       int                     ntwrds;
+       int                     nwrds;                  /* current number of words */
+       int                     ntwrds;                 /* allocated array length */
 
        /*
         * Storage of substituted result, n-th element is for n-th expression
@@ -298,7 +298,6 @@ thesaurusRead(char *filename, DictThesaurus *d)
 static TheLexeme *
 addCompiledLexeme(TheLexeme *newwrds, int *nnw, int *tnm, TSLexeme *lexeme, LexemeInfo *src, uint16 tnvariant)
 {
-
        if (*nnw >= *tnm)
        {
                *tnm *= 2;
@@ -453,7 +452,8 @@ compileTheLexeme(DictThesaurus *d)
                pfree(d->wrds[i].entries);
        }
 
-       pfree(d->wrds);
+       if (d->wrds)
+               pfree(d->wrds);
        d->wrds = newwrds;
        d->nwrds = nnw;
        d->ntwrds = tnm;