It's a common pattern, so add a helper for it. A macro is necessary
because a function that takes a pointer to a pointer would be type specific,
similarly to cleanup functions. Seems better to use a macro.
--- /dev/null
+@@
+expression p, q;
+@@
+- free(p);
+- p = q;
+- q = NULL;
+- return 0;
++ return free_and_replace(p, q);
+@@
+expression p, q;
+@@
+- free(p);
+- p = q;
+- q = NULL;
++ free_and_replace(p, q);
return NULL;
}
+#define free_and_replace(a, b) \
+ ({ \
+ free(a); \
+ (a) = (b); \
+ (b) = NULL; \
+ 0; \
+ })
+
void* memdup(const void *p, size_t l) _alloc_(2);
static inline void freep(void *p) {
!path_startswith(parent, root))
return -EINVAL;
- free(done);
- done = parent;
- parent = NULL;
+ free_and_replace(done, parent);
fd_parent = openat(fd, "..", O_CLOEXEC|O_NOFOLLOW|O_PATH);
if (fd_parent < 0)
if (fd < 0)
return -errno;
- free(buffer);
- buffer = destination;
- destination = NULL;
+ free_and_replace(buffer, destination);
todo = buffer;
free(done);
} else {
/* canonicalized path goes outside of
* prefix, keep the original path instead */
- free(u);
- u = orig;
- orig = NULL;
+ free_and_replace(u, orig);
}
} else
free(t);