Merge pull request #705 from sanpeqf/feat-guards

feat guards: added taken ptr function

Author: emhlb

examples/guards/cleanup.c

@@ -5,6 +5,7 @@
 
 #include <stdio.h>
 #include <stdlib.h>
+#include <unistd.h>
 #include <bfdev/guards.h>
 
 BFDEV_DEFINE_CLEAN(malloc, void *,
@@ -15,28 +16,28 @@ BFDEV_DEFINE_CLEAN(malloc, void *,
 )
 
 static void
-test_clean_gc(void)
+test_malloc_gc(void)
 {
     BFDEV_CLEAN(malloc) void *block;
     block = malloc(8);
     (void)block;
 }
 
 static void *
-test_clean_keep(void)
+test_malloc_keep(void)
 {
     BFDEV_CLEAN(malloc) void *block;
     block = malloc(8);
-    return bfdev_taken(block);
+    return bfdev_taken_ptr(block);
 }
 
 int
 main(int argc, const char *argv[])
 {
     void *block;
 
-    test_clean_gc();
-    block = test_clean_keep();
+    test_malloc_gc();
+    block = test_malloc_keep();
     free(block);
 
     return 0;

include/bfdev/guards.h

@@ -54,12 +54,15 @@ __bfdev_class_##name##_destructor(type *p)                  \
         __bfdev_cleanup(__bfdev_class_##name##_destructor) = \
         __bfdev_class_##name##_constructor
 
-#define bfdev_taken(object) ({      \
-    __auto_type __ptr = (object);   \
-    (object) = BFDEV_NULL;          \
-    __ptr;                          \
+#define bfdev_taken(freed, object) ({   \
+    __auto_type __object = (object);    \
+    (object) = (freed);                 \
+    __object;                           \
 })
 
+#define bfdev_taken_ptr(object) \
+    bfdev_taken(BFDEV_NULL, object)
+
 BFDEV_END_DECLS
 
 #endif /* _BFDEV_GUARDS_H_ */