From: Eric Biggers <ebiggers3@gmail.com>
Date: Thu, 15 Sep 2016 03:46:10 +0000 (-0700)
Subject: util.c: for aligned_malloc, store original pointer directly
X-Git-Tag: v1.11.0~65
X-Git-Url: https://wimlib.net/git/?p=wimlib;a=commitdiff_plain;h=26d5d280ea5394a573add55e1e22cb56a1515c4c;hp=c4bc1aa59275243ace4833073b0b4836a3bdfc2f

util.c: for aligned_malloc, store original pointer directly
---

diff --git a/src/util.c b/src/util.c
index 928a0368..e0c5cc1b 100644
--- a/src/util.c
+++ b/src/util.c
@@ -105,18 +105,13 @@ wimlib_wcsdup(const wchar_t *str)
 void *
 wimlib_aligned_malloc(size_t size, size_t alignment)
 {
-	wimlib_assert(alignment != 0 && is_power_of_2(alignment) &&
-		      alignment <= 4096);
-
-	const uintptr_t mask = alignment - 1;
-	char *ptr = NULL;
-	char *raw_ptr;
-
-	raw_ptr = MALLOC(mask + sizeof(size_t) + size);
-	if (raw_ptr) {
-		ptr = (char *)raw_ptr + sizeof(size_t);
-		ptr = (void *)(((uintptr_t)ptr + mask) & ~mask);
-		*((size_t *)ptr - 1) = ptr - raw_ptr;
+	wimlib_assert(is_power_of_2(alignment));
+
+	void *ptr = MALLOC(sizeof(void *) + alignment - 1 + size);
+	if (ptr) {
+		void *orig_ptr = ptr;
+		ptr = (void *)ALIGN((uintptr_t)ptr + sizeof(void *), alignment);
+		((void **)ptr)[-1] = orig_ptr;
 	}
 	return ptr;
 }
@@ -125,7 +120,7 @@ void
 wimlib_aligned_free(void *ptr)
 {
 	if (ptr)
-		FREE((char *)ptr - *((size_t *)ptr - 1));
+		FREE(((void **)ptr)[-1]);
 }
 
 void *