Alpm, check for NULL in free-functions

Also, use FREE() instead of free() in _alpm_backup_free()
to set the pointers to NULL.

Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com>
Signed-off-by: Allan McRae <allan@archlinux.org>

lib/libalpm/backup.c

@@ -76,9 +76,10 @@ alpm_backup_t *_alpm_needbackup(const char *file, alpm_pkg_t *pkg)
 
 void _alpm_backup_free(alpm_backup_t *backup)
 {
-	free(backup->name);
+	ASSERT(backup != NULL, return);
-	free(backup->hash);
+	FREE(backup->name);
-	free(backup);
+	FREE(backup->hash);
+	FREE(backup);
 }
 
 alpm_backup_t *_alpm_backup_dup(const alpm_backup_t *backup)

lib/libalpm/conflict.c

@@ -68,6 +68,7 @@ error:
  */
 void SYMEXPORT alpm_conflict_free(alpm_conflict_t *conflict)
 {
+	ASSERT(conflict != NULL, return);
 	FREE(conflict->package2);
 	FREE(conflict->package1);
 	FREE(conflict);
@@ -301,6 +302,7 @@ error:
  */
 void SYMEXPORT alpm_fileconflict_free(alpm_fileconflict_t *conflict)
 {
+	ASSERT(conflict != NULL, return);
 	FREE(conflict->ctarget);
 	FREE(conflict->file);
 	FREE(conflict->target);

lib/libalpm/db.c

@@ -344,6 +344,7 @@ alpm_db_t *_alpm_db_new(const char *treename, int is_local)
 
 void _alpm_db_free(alpm_db_t *db)
 {
+	ASSERT(db != NULL, return);
 	/* cleanup pkgcache */
 	_alpm_db_free_pkgcache(db);
 	/* cleanup server list */

lib/libalpm/delta.c

@@ -335,6 +335,7 @@ error:
 
 void _alpm_delta_free(alpm_delta_t *delta)
 {
+	ASSERT(delta != NULL, return);
 	FREE(delta->delta);
 	FREE(delta->delta_md5);
 	FREE(delta->from);

lib/libalpm/deps.c

@@ -37,6 +37,7 @@
 
 void SYMEXPORT alpm_dep_free(alpm_depend_t *dep)
 {
+	ASSERT(dep != NULL, return);
 	FREE(dep->name);
 	FREE(dep->version);
 	FREE(dep->desc);
@@ -63,6 +64,7 @@ error:
 
 void SYMEXPORT alpm_depmissing_free(alpm_depmissing_t *miss)
 {
+	ASSERT(miss != NULL, return);
 	alpm_dep_free(miss->depend);
 	FREE(miss->target);
 	FREE(miss->causingpkg);

lib/libalpm/graph.c

@@ -31,6 +31,7 @@ alpm_graph_t *_alpm_graph_new(void)
 
 void _alpm_graph_free(void *data)
 {
+	ASSERT(data != NULL, return);
 	alpm_graph_t *graph = data;
 	alpm_list_free(graph->children);
 	free(graph);