Merge branch 'ls/git-open-cloexec'

Git generally does not explicitly close file descriptors that were
open in the parent process when spawning a child process, but most
of the time the child does not want to access them. As Windows does
not allow removing or renaming a file that has a file descriptor
open, a slow-to-exit child can even break the parent process by
holding onto them.  Use O_CLOEXEC flag to open files in various
codepaths.

* ls/git-open-cloexec:
read-cache: make sure file handles are not inherited by child processes
sha1_file: open window into packfiles with O_CLOEXEC
sha1_file: rename git_open_noatime() to git_open()

diff --git a/builtin/pack-objects.c b/builtin/pack-objects.c
index 1e7c2a98a5617b8b42422c22051c5f61b2510751..0fd52bd6b4b985b24d93ab7fb9887f57305b49fd 100644 (file)
--- a/builtin/pack-objects.c
+++ b/builtin/pack-objects.c
@@ -720,7 +720,7 @@ static off_t write_reused_pack(struct sha1file *f)
        if (!is_pack_valid(reuse_packfile))
                die("packfile is invalid: %s", reuse_packfile->pack_name);
 
-       fd = git_open_noatime(reuse_packfile->pack_name);
+       fd = git_open(reuse_packfile->pack_name);
        if (fd < 0)
                die_errno("unable to open packfile for reuse: %s",
                          reuse_packfile->pack_name);

diff --git a/cache.h b/cache.h
index 1be6526d14fd66f2c854cdb01d0ef20d9151d6e1..a50a61a19787de94daa9d66caa9fcccca58081fe 100644 (file)
--- a/cache.h
+++ b/cache.h
@@ -1125,7 +1125,7 @@ extern int write_sha1_file(const void *buf, unsigned long len, const char *type,
 extern int hash_sha1_file_literally(const void *buf, unsigned long len, const char *type, unsigned char *sha1, unsigned flags);
 extern int pretend_sha1_file(void *, unsigned long, enum object_type, unsigned char *);
 extern int force_object_loose(const unsigned char *sha1, time_t mtime);
-extern int git_open_noatime(const char *name);
+extern int git_open(const char *name);
 extern void *map_sha1_file(const unsigned char *sha1, unsigned long *size);
 extern int unpack_sha1_header(git_zstream *stream, unsigned char *map, unsigned long mapsize, void *buffer, unsigned long bufsiz);
 extern int parse_sha1_header(const char *hdr, unsigned long *sizep);

diff --git a/pack-bitmap.c b/pack-bitmap.c
index b949e517167dbac6c4c347e0a2cbdf8ca2dabbcf..39bcc168463fc7358ab7cb4e963e6ed8bde94804 100644 (file)
--- a/pack-bitmap.c
+++ b/pack-bitmap.c
@@ -266,7 +266,7 @@ static int open_pack_bitmap_1(struct packed_git *packfile)
                return -1;
 
        idx_name = pack_bitmap_filename(packfile);
-       fd = git_open_noatime(idx_name);
+       fd = git_open(idx_name);
        free(idx_name);
 
        if (fd < 0)

diff --git a/read-cache.c b/read-cache.c
index 38d67faf708d7b88f208f10dad23f893dd16f587..db5d910642663e73e4e4fc8d91e0caba4445bdb1 100644 (file)
--- a/read-cache.c
+++ b/read-cache.c
@@ -156,7 +156,14 @@ void fill_stat_cache_info(struct cache_entry *ce, struct stat *st)
 static int ce_compare_data(const struct cache_entry *ce, struct stat *st)
 {
        int match = -1;
-       int fd = open(ce->name, O_RDONLY);
+       static int cloexec = O_CLOEXEC;
+       int fd = open(ce->name, O_RDONLY | cloexec);
+
+       if ((cloexec & O_CLOEXEC) && fd < 0 && errno == EINVAL) {
+               /* Try again w/o O_CLOEXEC: the kernel might not support it */
+               cloexec &= ~O_CLOEXEC;
+               fd = open(ce->name, O_RDONLY | cloexec);
+       }
 
        if (fd >= 0) {
                unsigned char sha1[20];

diff --git a/sha1_file.c b/sha1_file.c
index 1e41954a8480ab78366da6b302430ac090ee1aea..5457314e6aaaf1a30d33f68c8e1005f8db584564 100644 (file)
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -370,7 +370,7 @@ void read_info_alternates(const char * relative_base, int depth)
        int fd;
 
        path = xstrfmt("%s/info/alternates", relative_base);
-       fd = git_open_noatime(path);
+       fd = git_open(path);
        free(path);
        if (fd < 0)
                return;
@@ -663,7 +663,7 @@ static int check_packed_git_idx(const char *path, struct packed_git *p)
        struct pack_idx_header *hdr;
        size_t idx_size;
        uint32_t version, nr, i, *index;
-       int fd = git_open_noatime(path);
+       int fd = git_open(path);
        struct stat st;
 
        if (fd < 0)
@@ -1069,7 +1069,7 @@ static int open_packed_git_1(struct packed_git *p)
        while (pack_max_fds <= pack_open_fds && close_one_pack())
                ; /* nothing */
 
-       p->pack_fd = git_open_noatime(p->pack_name);
+       p->pack_fd = git_open(p->pack_name);
        if (p->pack_fd < 0 || fstat(p->pack_fd, &st))
                return -1;
        pack_open_fds++;
@@ -1586,9 +1586,9 @@ int check_sha1_signature(const unsigned char *sha1, void *map,
        return hashcmp(sha1, real_sha1) ? -1 : 0;
 }
 
-int git_open_noatime(const char *name)
+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;
@@ -1598,12 +1598,17 @@ int git_open_noatime(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;
        }
 }
@@ -1632,7 +1637,7 @@ static int open_sha1_file(const unsigned char *sha1)
        struct alternate_object_database *alt;
        int most_interesting_errno;
 
-       fd = git_open_noatime(sha1_file_name(sha1));
+       fd = git_open(sha1_file_name(sha1));
        if (fd >= 0)
                return fd;
        most_interesting_errno = errno;
@@ -1640,7 +1645,7 @@ static int open_sha1_file(const unsigned char *sha1)
        prepare_alt_odb();
        for (alt = alt_odb_list; alt; alt = alt->next) {
                const char *path = alt_sha1_path(alt, sha1);
-               fd = git_open_noatime(path);
+               fd = git_open(path);
                if (fd >= 0)
                        return fd;
                if (most_interesting_errno == ENOENT)