Fix bogus code in contrib/ tsearch dictionary examples.

Both dict_int and dict_xsyn were blithely assuming that whatever memory
palloc gives back will be pre-zeroed.  This would typically work for
just about long enough to run their regression tests, and no longer :-(.

The pre-9.0 code in dict_xsyn was even lamer than that, as it would
happily give back a pointer to the result of palloc(0), encouraging
its caller to access off the end of memory.  Again, this would just
barely fail to fail as long as memory contained nothing but zeroes.

Per a report from Rodrigo Hjort that code based on these examples
didn't work reliably.

diff --git a/contrib/dict_int/dict_int.c b/contrib/dict_int/dict_int.c
index c4ad6ef343e1c32b7fded47b0894a4e97b9d8b9d..ed82d83004c0ddb15f6d24ee9f85676a633bb39f 100644 (file)
--- a/contrib/dict_int/dict_int.c
+++ b/contrib/dict_int/dict_int.c
@@ -73,7 +73,7 @@ dintdict_lexize(PG_FUNCTION_ARGS)
        DictInt    *d = (DictInt *) PG_GETARG_POINTER(0);
        char       *in = (char *) PG_GETARG_POINTER(1);
        char       *txt = pnstrdup(in, PG_GETARG_INT32(2));
-       TSLexeme   *res = palloc(sizeof(TSLexeme) * 2);
+       TSLexeme   *res = palloc0(sizeof(TSLexeme) * 2);
 
        res[1].lexeme = NULL;
        if (PG_GETARG_INT32(2) > d->maxlen)

diff --git a/contrib/dict_xsyn/dict_xsyn.c b/contrib/dict_xsyn/dict_xsyn.c
index ded20facd47cb1ed01559dcc824726754e9a124e..18301effc7c8176922f841c49918c3fe8dbdb817 100644 (file)
--- a/contrib/dict_xsyn/dict_xsyn.c
+++ b/contrib/dict_xsyn/dict_xsyn.c
@@ -245,6 +245,8 @@ dxsyn_lexize(PG_FUNCTION_ARGS)
                        if (pos != value || d->keeporig)
                        {
                                res[nsyns].lexeme = pnstrdup(syn, end - syn);
+                               res[nsyns].nvariant = 0;
+                               res[nsyns].flags = 0;
                                nsyns++;
                        }