path: root/dir.c
diff options
authorShawn O. Pearce <>2007-03-07 01:44:37 (GMT)
committerJunio C Hamano <>2007-03-07 19:15:26 (GMT)
commitdc49cd769b5fa6b7e0114b051c34a849828a7603 (patch)
tree7eafafcd36ab731599da3fb5e59d3f4379c342d3 /dir.c
parent6777a59fcdfd96b9ca5cba49cb265c6c47de3d02 (diff)
Cast 64 bit off_t to 32 bit size_t
Some systems have sizeof(off_t) == 8 while sizeof(size_t) == 4. This implies that we are able to access and work on files whose maximum length is around 2^63-1 bytes, but we can only malloc or mmap somewhat less than 2^32-1 bytes of memory. On such a system an implicit conversion of off_t to size_t can cause the size_t to wrap, resulting in unexpected and exciting behavior. Right now we are working around all gcc warnings generated by the -Wshorten-64-to-32 option by passing the off_t through xsize_t(). In the future we should make xsize_t on such problematic platforms detect the wrapping and die if such a file is accessed. Signed-off-by: Shawn O. Pearce <> Signed-off-by: Junio C Hamano <>
Diffstat (limited to 'dir.c')
1 files changed, 2 insertions, 2 deletions
diff --git a/dir.c b/dir.c
index 32b57f0..b48e19d 100644
--- a/dir.c
+++ b/dir.c
@@ -130,13 +130,13 @@ static int add_excludes_from_file_1(const char *fname,
struct stat st;
int fd, i;
- long size;
+ size_t size;
char *buf, *entry;
fd = open(fname, O_RDONLY);
if (fd < 0 || fstat(fd, &st) < 0)
goto err;
- size = st.st_size;
+ size = xsize_t(st.st_size);
if (size == 0) {
return 0;