From dc49cd769b5fa6b7e0114b051c34a849828a7603 Mon Sep 17 00:00:00 2001 From: "Shawn O. Pearce" Date: Tue, 6 Mar 2007 20:44:37 -0500 Subject: 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 --- builtin-blame.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'builtin-blame.c') diff --git a/builtin-blame.c b/builtin-blame.c index 20966b9e02..b51cdc71fa 100644 --- a/builtin-blame.c +++ b/builtin-blame.c @@ -1963,7 +1963,7 @@ static struct commit *fake_working_tree_commit(const char *path, const char *con die("Cannot lstat %s", path); read_from = path; } - fin_size = st.st_size; + fin_size = xsize_t(st.st_size); buf = xmalloc(fin_size+1); mode = canon_mode(st.st_mode); switch (st.st_mode & S_IFMT) { -- cgit v1.2.3