[PATCH] xsize_t: check whether we lose bits
- From
Thomas Rast <trast@student.ethz.ch>
- Date
- Jul 28, 2010, 16:36 UTC
- Message-ID
- <a619b6d672b4d01ce4107566267ba9b67904652b.1280334553.git.trast@student.ethz.ch>
Attempting to mmap (via git-add or similar) a file larger than 4GB on 32-bit Linux systems results in a repository that has only the file modulo 4GB stored, because of truncation of the off_t file size to a size_t for mmap.
When xsize_t was introduced to handle this truncation in dc49cd7 (Cast 64 bit off_t to 32 bit size_t, 2007-03-06), Shawn even pointed out that it should detect when such a cutoff happens.
Make it so.
Signed-off-by: Thomas Rast <trast@student.ethz.ch> ---
Of course this does not fix the underlying issue that we want to mmap the file, so you still cannot add them.
Also, I must be missing something, this patch is way too simple.
git-compat-util.h | 2 ++ 1 files changed, 2 insertions(+), 0 deletions(-)
diff --git a/git-compat-util.h b/git-compat-util.h index 02a73ee..fe845ae 100644 --- a/git-compat-util.h +++ b/git-compat-util.h @@ -388,6 +388,8 @@ extern int odb_pack_keep(char *name, size_t namesz, unsigned char *sha1); static inline size_t xsize_t(off_t len) { + if (len > (size_t) len) + die("Cannot handle files this big"); return (size_t)len; }
-- 1.7.2.349.gd5452