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authorRich Felker <dalias@aerifal.cx>2011-11-16 23:59:28 -0500
committerRich Felker <dalias@aerifal.cx>2011-11-16 23:59:28 -0500
commite5d78fe8df9bd61940abcd98ad07ed69b7da4350 (patch)
tree487e681d1f13d0fab839d7a78b944828bed31e61 /src/malloc/malloc.c
parent4e3df7be8ff430de6f0f124a20112fb7be8a17d0 (diff)
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fix issue with excessive mremap syscalls on realloc
CHUNK_SIZE macro was defined incorrectly and shaving off at least one
significant bit in the size of mmapped chunks, resulting in the test
for oldlen==newlen always failing and incurring a syscall. fortunately
i don't think this issue caused any other observable behavior; the
definition worked correctly for all non-mmapped chunks where its
correctness matters more, since their lengths are always multiples of
the alignment.
Diffstat (limited to 'src/malloc/malloc.c')
-rw-r--r--src/malloc/malloc.c6
1 files changed, 2 insertions, 4 deletions
diff --git a/src/malloc/malloc.c b/src/malloc/malloc.c
index abf3e8fa..39c7d051 100644
--- a/src/malloc/malloc.c
+++ b/src/malloc/malloc.c
@@ -43,8 +43,8 @@ static struct {
 #define DONTCARE 16
 #define RECLAIM 163840
 
-#define CHUNK_SIZE(c) ((c)->csize & SIZE_MASK)
-#define CHUNK_PSIZE(c) ((c)->psize & SIZE_MASK)
+#define CHUNK_SIZE(c) ((c)->csize & -2)
+#define CHUNK_PSIZE(c) ((c)->psize & -2)
 #define PREV_CHUNK(c) ((struct chunk *)((char *)(c) - CHUNK_PSIZE(c)))
 #define NEXT_CHUNK(c) ((struct chunk *)((char *)(c) + CHUNK_SIZE(c)))
 #define MEM_TO_CHUNK(p) (struct chunk *)((char *)(p) - OVERHEAD)
@@ -52,8 +52,6 @@ static struct {
 #define BIN_TO_CHUNK(i) (MEM_TO_CHUNK(&mal.bins[i].head))
 
 #define C_INUSE  ((size_t)1)
-#define C_FLAGS  ((size_t)3)
-#define C_SIZE   SIZE_MASK
 
 #define IS_MMAPPED(c) !((c)->csize & (C_INUSE))