Speed up ast_list macros (bug #3135)

git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@4546 65c4cc65-6c06-0410-ace0-fbb531ad65f3

channel.c

@@ -641,8 +641,7 @@ void ast_channel_free(struct ast_channel *chan)
 	/* no need to lock the list, as the channel is already locked */
 	
 	while (!AST_LIST_EMPTY(headp)) {           /* List Deletion. */
-	            vardata = AST_LIST_FIRST(headp);
+	            vardata = AST_LIST_REMOVE_HEAD(headp, ast_var_t, entries);
-	            AST_LIST_REMOVE_HEAD(headp, entries);
 /*	            printf("deleting var %s=%s\n",ast_var_name(vardata),ast_var_value(vardata)); */
 	            ast_var_delete(vardata);
 	}

doc/linkedlists.README

@@ -48,9 +48,10 @@ AST_LIST_REMOVE removes an arbitrary element from the head:
 
 	AST_LIST_REMOVE(headp,node1,ast_var_t,listpointers);
 
-AST_LIST_REMOVE_HEAD removes the entry at the head of the list: 
+AST_LIST_REMOVE_HEAD removes the entry at the head of the list and
+returns a pointer to the removed entry: 
 
-	AST_LIST_REMOVE(headp,listpointers);
+	AST_LIST_REMOVE_HEAD(headp,node,listpointers);
 
 AST_LIST_FIRST returns a pointer to the first element of the list;
 
@@ -78,8 +79,7 @@ To completely delete a list :
 	struct ast_var_t *vardata;
 
         while (!AST_LIST_EMPTY(headp)) {           /* List Deletion. */
-                    vardata = AST_LIST_FIRST(head);
+                    vardata = AST_LIST_REMOVE_HEAD(head, ast_var_t, listpointers);
-                    AST_LIST_REMOVE_HEAD(head, listpointers);
                     free(vardata->name);
 		    free(vardata->value);
         }

include/asterisk/linkedlists.h

@@ -62,13 +62,15 @@ struct {								\
 } while (0)
 
 
-#define AST_LIST_REMOVE_HEAD(head, field) do {					\
+#define AST_LIST_REMOVE_HEAD(head, type, field) ({				\
+		struct type *cur = (head)->first;				\
 		(head)->first = (head)->first->field.next;			\
-	} while (0)
+		cur;								\
+	})
 
 #define AST_LIST_REMOVE(head, elm, type, field) do {			\
 	if ((head)->first == (elm)) {					\
-		AST_LIST_REMOVE_HEAD((head), field);			\
+		AST_LIST_REMOVE_HEAD((head), type, field);		\
 	}								\
 	else {								\
 		struct type *curelm = (head)->first;			\

pbx.c

@@ -5123,8 +5123,7 @@ void pbx_builtin_clear_globals(void)
 {
 	struct ast_var_t *vardata;
 	while (!AST_LIST_EMPTY(&globals)) {
-		vardata = AST_LIST_FIRST(&globals);
+		vardata = AST_LIST_REMOVE_HEAD(&globals, ast_var_t, entries);
-		AST_LIST_REMOVE_HEAD(&globals, entries);
 		ast_var_delete(vardata);
 	}
 }

pbx/pbx_dundi.c

@@ -551,8 +551,7 @@ static int dundi_lookup_local(struct dundi_result *dr, struct dundi_mapping *map
 				AST_LIST_INSERT_HEAD(&headp, newvariable, entries);
 				pbx_substitute_variables_varshead(&headp, map->dest, dr[anscnt].dest, sizeof(dr[anscnt].dest));
 				while (!AST_LIST_EMPTY(&headp)) {           /* List Deletion. */
-					newvariable = AST_LIST_FIRST(&headp);
+					newvariable = AST_LIST_REMOVE_HEAD(&headp, ast_var_t, entries);
-					AST_LIST_REMOVE_HEAD(&headp, entries);
 					ast_var_delete(newvariable);
 				}
 			} else

pbx/pbx_loopback.c

@@ -81,8 +81,7 @@ static char *loopback_helper(char *buf, int buflen, const char *exten, const cha
 	pbx_substitute_variables_varshead(&headp, data, buf, buflen);
 	/* Substitute variables */
 	while (!AST_LIST_EMPTY(&headp)) {           /* List Deletion. */
-		newvariable = AST_LIST_FIRST(&headp);
+		newvariable = AST_LIST_REMOVE_HEAD(&headp, ast_var_t, entries);
-		AST_LIST_REMOVE_HEAD(&headp, entries);
 		ast_var_delete(newvariable);
 	}
 	return buf;