ctdb-daemon: Simplify listing event scripts using scandir

Instead of using RB tree for sorting the script names (incorrectly since
it's only using the leading numbers in the script name), use scandir
with alphasort.

Signed-off-by: Amitay Isaacs <amitay@gmail.com>
Reviewed-by: Martin Schwenke <martin@meltin.net>

Autobuild-User(master): Martin Schwenke <martins@samba.org>
Autobuild-Date(master): Tue Jan 21 06:41:25 CET 2014 on sn-devel-104

ctdb/server/eventscript.c

@@ -100,10 +100,33 @@ int32_t ctdb_control_get_event_script_status(struct ctdb_context *ctdb,
 	return 0;
 }
 
-struct ctdb_script_tree_item {
+/* To ignore directory entry return 0, else return non-zero */
-	const char *name;
+static int script_filter(const struct dirent *de)
-	int error;
+{
-};
+	int namelen = strlen(de->d_name);
+
+	/* Ignore . and .. */
+	if (namelen < 3) {
+		return 0;
+	}
+
+	/* Skip temporary files left behind by emacs */
+	if (de->d_name[namelen-1] == '~') {
+		return 0;
+	}
+
+	/* Filename should start with [0-9][0-9]. */
+	if (!isdigit(de->d_name[0]) || !isdigit(de->d_name[1]) ||
+	    de->d_name[2] != '.') {
+		return 0;
+	}
+
+	if (namelen > MAX_SCRIPT_NAME) {
+		return 0;
+	}
+
+	return 1;
+}
 
 /* Return true if OK, otherwise set errno. */
 static bool check_executable(const char *dir, const char *name)
@@ -135,117 +158,40 @@ static bool check_executable(const char *dir, const char *name)
 
 static struct ctdb_scripts_wire *ctdb_get_script_list(struct ctdb_context *ctdb, TALLOC_CTX *mem_ctx)
 {
-	DIR *dir;
+	struct dirent **namelist;
-	struct dirent *de;
-	struct stat st;
-	trbt_tree_t *tree;
 	struct ctdb_scripts_wire *scripts;
-	TALLOC_CTX *tmp_ctx = talloc_new(ctdb);
-	struct ctdb_script_tree_item *tree_item;
 	int count;
 
-	/*
-	  the service specific event scripts 
-	*/
-	if (stat(ctdb->event_script_dir, &st) != 0 && 
-	    errno == ENOENT) {
-		DEBUG(DEBUG_CRIT,("No event script directory found at '%s'\n", ctdb->event_script_dir));
-		talloc_free(tmp_ctx);
-		return NULL;
-	}
-
-	/* create a tree to store all the script names in */
-	tree = trbt_create(tmp_ctx, 0);
-
 	/* scan all directory entries and insert all valid scripts into the 
 	   tree
 	*/
-	dir = opendir(ctdb->event_script_dir);
+	count = scandir(ctdb->event_script_dir, &namelist, script_filter, alphasort);
-	if (dir == NULL) {
+	if (count == -1) {
-		DEBUG(DEBUG_CRIT,("Failed to open event script directory '%s'\n", ctdb->event_script_dir));
+		DEBUG(DEBUG_CRIT, ("Failed to read event script directory '%s' - %s\n",
-		talloc_free(tmp_ctx);
+				   ctdb->event_script_dir, strerror(errno)));
 		return NULL;
 	}
 
-	count = 0;
-	while ((de=readdir(dir)) != NULL) {
-		int namlen;
-		unsigned num;
-
-		namlen = strlen(de->d_name);
-
-		if (namlen < 3) {
-			continue;
-		}
-
-		if (de->d_name[namlen-1] == '~') {
-			/* skip files emacs left behind */
-			continue;
-		}
-
-		if (de->d_name[2] != '.') {
-			continue;
-		}
-
-		if (sscanf(de->d_name, "%02u.", &num) != 1) {
-			continue;
-		}
-
-		if (strlen(de->d_name) > MAX_SCRIPT_NAME) {
-			DEBUG(DEBUG_ERR,("Script name %s too long! %u chars max",
-					 de->d_name, MAX_SCRIPT_NAME));
-			continue;
-		}
-
-		tree_item = talloc(tree, struct ctdb_script_tree_item);
-		if (tree_item == NULL) {
-			DEBUG(DEBUG_ERR, (__location__ " Failed to allocate new tree item\n"));
-			closedir(dir);
-			talloc_free(tmp_ctx);
-			return NULL;
-		}
-	
-		tree_item->error = 0;
-		if (!check_executable(ctdb->event_script_dir, de->d_name)) {
-			tree_item->error = errno;
-		}
-
-		tree_item->name = talloc_strdup(tree_item, de->d_name);
-		if (tree_item->name == NULL) {
-			DEBUG(DEBUG_ERR,(__location__ " Failed to allocate script name.\n"));
-			closedir(dir);
-			talloc_free(tmp_ctx);
-			return NULL;
-		}
-
-		/* store the event script in the tree */
-		trbt_insert32(tree, (num<<16)|count++, tree_item);
-	}
-	closedir(dir);
-
 	/* Overallocates by one, but that's OK */
-	scripts = talloc_zero_size(tmp_ctx,
+	scripts = talloc_zero_size(mem_ctx,
 				   sizeof(*scripts)
 				   + sizeof(scripts->scripts[0]) * count);
 	if (scripts == NULL) {
 		DEBUG(DEBUG_ERR, (__location__ " Failed to allocate scripts\n"));
-		talloc_free(tmp_ctx);
+		free(namelist);
 		return NULL;
 	}
 	scripts->num_scripts = count;
 
 	for (count = 0; count < scripts->num_scripts; count++) {
-		tree_item = trbt_findfirstarray32(tree, 1);
+		strcpy(scripts->scripts[count].name, namelist[count]->d_name);
-
+		scripts->scripts[count].status = 0;
-		strcpy(scripts->scripts[count].name, tree_item->name);
+		if (!check_executable(ctdb->event_script_dir, namelist[count]->d_name)) {
-		scripts->scripts[count].status = -tree_item->error;
+			scripts->scripts[count].status = -errno;
-
+		}
-		/* remove this script from the tree */
-		talloc_free(tree_item);
 	}
 
-	talloc_steal(mem_ctx, scripts);
+	free(namelist);
-	talloc_free(tmp_ctx);
 	return scripts;
 }