Add macros for iterating the containing entry

test/tailq_example.c

@@ -23,32 +23,38 @@ void add_block(struct File *f, const char *txt)
 
 void print_file(struct File *f)
 {
-    struct TailQ *entry;
+    struct Block *entry;
     printf("File: %s\n", f->name);
-    UC_TAILQ_FOREACH(entry, &f->head) {
-        struct Block *b = UC_CONTAINER_OF(entry, struct Block, blocks);
-        printf("Block: %s\n", b->text);
+    UC_TAILQ_FOREACH_CONTAINER(entry, blocks, &f->head) {
+        printf("Block: %s\n", entry->text);
+    }
+}
+
+void print_file_reverse(struct File *f)
+{
+    struct Block *entry;
+    printf("File: %s\n", f->name);
+    UC_TAILQ_FOREACH_REVERSE_CONTAINER(entry, blocks, &f->head) {
+        printf("Block: %s\n", entry->text);
     }
 }
 
 void delete_block(struct File *f, const char *txt)
 {
-    struct TailQ *entry, *next;
-    UC_TAILQ_FOREACH_SAFE(entry, next, &f->head) {
-        struct Block *b = UC_CONTAINER_OF(entry, struct Block, blocks);
-        if (strcmp(txt, b->text) == 0) {
-            uc_tailq_remove(entry);
-            free(b);
+    struct Block *entry, *next;
+    UC_TAILQ_FOREACH_CONTAINER_SAFE(entry, next, blocks, &f->head) {
+        if (strcmp(txt, entry->text) == 0) {
+            uc_tailq_remove(&entry->blocks);
+            free(entry);
         }
     }
 }
 
 void delete_all_blocks(struct File *f)
 {
-    struct TailQ *entry, *next;
-    UC_TAILQ_FOREACH_SAFE(entry, next, &f->head) {
-        struct Block *b = UC_CONTAINER_OF(entry, struct Block, blocks);
-        free(b);
+    struct Block *entry, *next;
+    UC_TAILQ_FOREACH_CONTAINER_SAFE(entry, next, blocks, &f->head) {
+        free(entry);
     }
     uc_tailq_init(&f->head);
 }
@@ -74,6 +80,8 @@ int main(void)
     add_block(&f,"three");
     add_block(&f,"three");
     print_file(&f);
+    puts("\nReverse order:");
+    print_file_reverse(&f);
 
     puts("\nDeleting three");
     delete_block(&f, "three");