PERFORCE change 127141 for review

[Fredrik Lindberg]

http://perforce.freebsd.org/chv.cgi?CH=127141

Change 127141 by fli at fli_nexus on 2007/10/03 21:01:46

	- Add hashtbl_flush() that flushes all entries without
	  destroying the table itself.
	- Add missing checks for failed memory allocations.
	- Plug a memory leak, some memory wasn't freed properly
	  when the table was destroyed.

Affected files ...

.. //depot/projects/soc2007/fli-mdns_sd/mdnsd/hash.c#7 edit
.. //depot/projects/soc2007/fli-mdns_sd/mdnsd/hash.h#7 edit

Differences ...

==== //depot/projects/soc2007/fli-mdns_sd/mdnsd/hash.c#7 (text+ko) ====

@@ -248,6 +248,8 @@
 		len = 1 << ht->ht_alloc_size;
 		hep = malloc(sizeof(struct he_pool) +
 		    (sizeof(struct hashentry) * len));
+		if (hep == NULL)
+			return (NULL);
 		hep->hep_size = len;
 		hep->hep_pos = 0;
 		SLIST_INSERT_HEAD(&ht->ht_new, hep, hep_next);
@@ -291,6 +293,8 @@
 	ht->ht_mask = ht->ht_tblsz - 1;
 
 	bkts = malloc(sizeof(struct hashbkt) * ht->ht_tblsz);
+	if (bkts == NULL)
+		return;
 	for (i = 0; i < ht->ht_tblsz; i++) {
 		TAILQ_INIT(&bkts[i].hb_table);
 		bkts[i].hb_len = 0;
@@ -320,6 +324,8 @@
 	size_t i;
 
 	ht->ht_bkts = malloc(sizeof(struct hashbkt) * len);
+	if (ht->ht_bkts == NULL)
+		return (-1);
 	ht->ht_tblsz = len;
 	ht->ht_grow = growsz;
 	ht->ht_col = col;
@@ -342,16 +348,9 @@
 void
 hashtbl_destroy(struct hashtbl *ht)
 {
-	struct hashentry *he;
 	struct he_pool *hep, *hep2;
-	size_t i;
 
-	for (i = 0; i < ht->ht_tblsz; i++) {
-		TAILQ_FOREACH(he, &ht->ht_bkts[i].hb_table, he_next) {
-			if (he->he_flags & HASHTBL_KEYDUP)
-				free(he->he_key.vol);
-		}
-	}
+	hashtbl_flush(ht);
 	SLIST_FOREACH_SAFE(hep, &ht->ht_new, hep_next, hep2) {
 		free(hep);
 	}
@@ -401,6 +400,8 @@
 		return (-1);
 
 	he = alloc_he(ht);
+	if (he == NULL)
+		return (-1);
 
 	he->he_hash = hval;
 	hval &= ht->ht_mask;
@@ -408,6 +409,8 @@
 
 	if (flags & HASHTBL_KEYDUP) {
 		he->he_key.vol = malloc(keylen);
+		if (he->he_key.vol == NULL)
+			return (-1);
 		memcpy(he->he_key.vol, key, keylen);
 	}
 	else {
@@ -512,3 +515,23 @@
 		}
 	}
 }
+
+/*
+ * Flush all entries in table without destroying it
+ *   ht - hash table
+ */
+void
+hashtbl_flush(struct hashtbl *ht)
+{
+	struct hashentry *he, *he2;
+	size_t i;
+
+	for (i = 0; i < ht->ht_tblsz; i++) {
+		TAILQ_FOREACH_SAFE(he, &ht->ht_bkts[i].hb_table, he_next, he2) {
+			TAILQ_REMOVE(&ht->ht_bkts[i].hb_table, he, he_next);
+			if (he->he_flags & HASHTBL_KEYDUP)
+				free(he->he_key.vol);
+			free_he(ht, he);
+		}
+	}
+}

==== //depot/projects/soc2007/fli-mdns_sd/mdnsd/hash.h#7 (text+ko) ====

@@ -86,5 +86,6 @@
 int hashtbl_del(struct hashtbl *, const void *, size_t);
 void * hashtbl_find(struct hashtbl *, const void *, size_t);
 void hashtbl_walk(struct hashtbl *, hashtbl_cb, void *);
+void hashtbl_flush(struct hashtbl *);
 
 #endif /* _HASH_H_ */