Subject: [PATCH] pack-bitmaps: plug memory leak, fix allocation size for recent_bitmaps

From: René Scharfe <[email-masked]>
Date: Tue, 19 May 2015 01:24:09 +0200

Use an automatic variable for recent_bitmaps, an array of pointers.
This way we don't allocate too much and don't have to free the memory
at the end.  The old code over-allocated because it reserved enough
memory to store all of the structs it is only pointing to and never
freed it.  160 64-bit pointers take up 1280 bytes, which is not too
much to be placed on the stack.

MAX_XOR_OFFSET is turned into a preprocessor constant to make it
constant enough for use in an non-variable array declaration.

Noticed-by: Stefan Beller <[email-masked]>
Suggested-by: Jeff King <[email-masked]>
Signed-off-by: Rene Scharfe <[email-masked]>
---
This seems to have fallen through the cracks, or did I just miss it?

 pack-bitmap.c | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/pack-bitmap.c b/pack-bitmap.c
index 62a98cc..e5abb8a 100644
--- a/pack-bitmap.c
+++ b/pack-bitmap.c
@@ -209,14 +209,12 @@ static inline uint8_t read_u8(const unsigned char *buffer, size_t *pos)
 	return buffer[(*pos)++];
 }
 
+#define MAX_XOR_OFFSET 160
+
 static int load_bitmap_entries_v1(struct bitmap_index *index)
 {
-	static const size_t MAX_XOR_OFFSET = 160;
-
 	uint32_t i;
-	struct stored_bitmap **recent_bitmaps;
-
-	recent_bitmaps = xcalloc(MAX_XOR_OFFSET, sizeof(struct stored_bitmap));
+	struct stored_bitmap *recent_bitmaps[MAX_XOR_OFFSET] = { NULL };
 
 	for (i = 0; i < index->entry_count; ++i) {
 		int xor_offset, flags;
-- 
2.4.1