src/kwset.c (kwsincr, kwsprep): obstack_alloc()-related fixes

[Charles Levert]

Proposed patch; I'll write a ChangeLog entry if
it's accepted.

The added call to obstack_free() will pop the top
allocation off the obstack, which just succeeded
before the last one failed.  It's just to keep
things clean.



--- src/kwset.c 2005-07-04 01:14:37 -0400
+++ src/kwset.c 2005-07-04 09:39:09 -0400
@@ -176,7 +176,10 @@ kwsincr (kwset_t kws, char const *text, 
          link->trie = (struct trie *) obstack_alloc(&kwset->obstack,
                                                     sizeof (struct trie));
          if (!link->trie)
-           return _("memory exhausted");
+           {
+             obstack_free(&kwset->obstack, link);
+             return _("memory exhausted");
+           }
          link->trie->accepting = 0;
          link->trie->links = NULL;
          link->trie->parent = trie;
@@ -397,6 +400,8 @@ kwsprep (kwset_t kws)
 
       /* Looking for just one string.  Extract it from the trie. */
       kwset->target = obstack_alloc(&kwset->obstack, kwset->mind);
+      if (!kwset->target)
+       return _("memory exhausted");
       for (i = kwset->mind - 1, curr = kwset->trie; i >= 0; --i)
        {
          kwset->target[i] = curr->links->label;