diff options
| -rw-r--r-- | src/glsl/list.h | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/src/glsl/list.h b/src/glsl/list.h index b5a413dc51..48502fb4c8 100644 --- a/src/glsl/list.h +++ b/src/glsl/list.h @@ -421,6 +421,20 @@ struct exec_list { #endif }; +/** + * This version is safe even if the current node is removed. If you insert + * new nodes before the current node, they will be processed next. + * + * \note + * The extra test for \c __node being \c NULL is required because after the + * iteration \c __prev coupld be the last node in the list. The loop increment + * then causes \c __prev to point to the sentinal and \c __node to be \c NULL. + */ +#define foreach_list_safe(__node, __list) \ + for (exec_node * __prev = (exec_node *) (__list), * __node = (__list)->head \ + ; __node != NULL && (__node)->next != NULL \ + ; __prev = (__prev)->next, __node = (__prev)->next) + #define foreach_list(__node, __list) \ for (exec_node * __node = (__list)->head \ ; (__node)->next != NULL \ |