sha1_file: open window into packfiles with O_CLOEXEC

All processes that the Git main process spawns inherit the open file
descriptors of the main process. These leaked file descriptors can
cause problems.

Use the O_CLOEXEC flag similar to 05d1ed61 to fix the leaked file
descriptors.

Signed-off-by: Lars Schneider <larsxschneider@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/sha1_file.c b/sha1_file.c
index 5d2bcd3ed13cb2ca2a4645fdc968ed4580dcaf35..09045df1dcd8cf3dcda47ef6114ee68eb4c5f3be 100644 (file)
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -1561,7 +1561,7 @@ int check_sha1_signature(const unsigned char *sha1, void *map,
 
 int git_open(const char *name)
 {
-       static int sha1_file_open_flag = O_NOATIME;
+       static int sha1_file_open_flag = O_NOATIME | O_CLOEXEC;
 
        for (;;) {
                int fd;
@@ -1571,12 +1571,17 @@ int git_open(const char *name)
                if (fd >= 0)
                        return fd;
 
-               /* Might the failure be due to O_NOATIME? */
-               if (errno != ENOENT && sha1_file_open_flag) {
-                       sha1_file_open_flag = 0;
+               /* Try again w/o O_CLOEXEC: the kernel might not support it */
+               if ((sha1_file_open_flag & O_CLOEXEC) && errno == EINVAL) {
+                       sha1_file_open_flag &= ~O_CLOEXEC;
                        continue;
                }
 
+               /* Might the failure be due to O_NOATIME? */
+               if (errno != ENOENT && (sha1_file_open_flag & O_NOATIME)) {
+                       sha1_file_open_flag &= ~O_NOATIME;
+                       continue;
+               }
                return -1;
        }
 }