Initial version

1 files changed, 13 insertions, 0 deletions

diff --git a/src/malloc/mallocng/malloc_usable_size.c b/src/malloc/mallocng/malloc_usable_size.c
new file mode 100644
index 0000000..ce6a960
--- /dev/null
+++ b/src/malloc/mallocng/malloc_usable_size.c
@@ -0,0 +1,13 @@
+#include <stdlib.h>
+#include "meta.h"
+
+size_t malloc_usable_size(void *p)
+{
+	if (!p) return 0;
+	struct meta *g = get_meta(p);
+	int idx = get_slot_index(p);
+	size_t stride = get_stride(g);
+	unsigned char *start = g->mem->storage + stride*idx;
+	unsigned char *end = start + stride - IB;
+	return get_nominal_size(p, end);
+}