зеркало из https://github.com/microsoft/git.git
lockfile.c: introduce 'hold_lock_file_for_update_mode'
We use 'hold_lock_file_for_update' (and the '_timeout') variant to acquire a lock when updating references, the commit-graph file, and so on. In particular, the commit-graph machinery uses this to acquire a temporary file that is used to write a non-split commit-graph. In a subsequent commit, an issue in the commit-graph machinery produces graph files that have a different permission based on whether or not they are part of a multi-layer graph will be addressed. To do so, the commit-graph machinery will need a version of 'hold_lock_file_for_update' that takes the permission bits from the caller. Introduce such a function in this patch for both the 'hold_lock_file_for_update' and 'hold_lock_file_for_update_timeout' functions, and leave the existing functions alone by inlining their definitions in terms of the new mode variants. Note that, like in the previous commit, 'hold_lock_file_for_update_mode' is not guarenteed to set the given mode, since it may be modified by both the umask and 'core.sharedRepository'. Note also that even though the commit-graph machinery only calls 'hold_lock_file_for_update', that this is defined in terms of 'hold_lock_file_for_update_timeout', and so both need an additional mode parameter here. Signed-off-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit is contained in:
Родитель
bef0413c35
Коммит
fa3bff2466
18
lockfile.c
18
lockfile.c
|
@ -70,7 +70,8 @@ static void resolve_symlink(struct strbuf *path)
|
|||
}
|
||||
|
||||
/* Make sure errno contains a meaningful value on error */
|
||||
static int lock_file(struct lock_file *lk, const char *path, int flags)
|
||||
static int lock_file(struct lock_file *lk, const char *path, int flags,
|
||||
int mode)
|
||||
{
|
||||
struct strbuf filename = STRBUF_INIT;
|
||||
|
||||
|
@ -79,7 +80,7 @@ static int lock_file(struct lock_file *lk, const char *path, int flags)
|
|||
resolve_symlink(&filename);
|
||||
|
||||
strbuf_addstr(&filename, LOCK_SUFFIX);
|
||||
lk->tempfile = create_tempfile(filename.buf);
|
||||
lk->tempfile = create_tempfile_mode(filename.buf, mode);
|
||||
strbuf_release(&filename);
|
||||
return lk->tempfile ? lk->tempfile->fd : -1;
|
||||
}
|
||||
|
@ -99,7 +100,7 @@ static int lock_file(struct lock_file *lk, const char *path, int flags)
|
|||
* exactly once. If timeout_ms is -1, try indefinitely.
|
||||
*/
|
||||
static int lock_file_timeout(struct lock_file *lk, const char *path,
|
||||
int flags, long timeout_ms)
|
||||
int flags, long timeout_ms, int mode)
|
||||
{
|
||||
int n = 1;
|
||||
int multiplier = 1;
|
||||
|
@ -107,7 +108,7 @@ static int lock_file_timeout(struct lock_file *lk, const char *path,
|
|||
static int random_initialized = 0;
|
||||
|
||||
if (timeout_ms == 0)
|
||||
return lock_file(lk, path, flags);
|
||||
return lock_file(lk, path, flags, mode);
|
||||
|
||||
if (!random_initialized) {
|
||||
srand((unsigned int)getpid());
|
||||
|
@ -121,7 +122,7 @@ static int lock_file_timeout(struct lock_file *lk, const char *path,
|
|||
long backoff_ms, wait_ms;
|
||||
int fd;
|
||||
|
||||
fd = lock_file(lk, path, flags);
|
||||
fd = lock_file(lk, path, flags, mode);
|
||||
|
||||
if (fd >= 0)
|
||||
return fd; /* success */
|
||||
|
@ -169,10 +170,11 @@ NORETURN void unable_to_lock_die(const char *path, int err)
|
|||
}
|
||||
|
||||
/* This should return a meaningful errno on failure */
|
||||
int hold_lock_file_for_update_timeout(struct lock_file *lk, const char *path,
|
||||
int flags, long timeout_ms)
|
||||
int hold_lock_file_for_update_timeout_mode(struct lock_file *lk,
|
||||
const char *path, int flags,
|
||||
long timeout_ms, int mode)
|
||||
{
|
||||
int fd = lock_file_timeout(lk, path, flags, timeout_ms);
|
||||
int fd = lock_file_timeout(lk, path, flags, timeout_ms, mode);
|
||||
if (fd < 0) {
|
||||
if (flags & LOCK_DIE_ON_ERROR)
|
||||
unable_to_lock_die(path, errno);
|
||||
|
|
32
lockfile.h
32
lockfile.h
|
@ -90,6 +90,15 @@
|
|||
* functions. In particular, the state diagram and the cleanup
|
||||
* machinery are all implemented in the tempfile module.
|
||||
*
|
||||
* Permission bits
|
||||
* ---------------
|
||||
*
|
||||
* If you call either `hold_lock_file_for_update_mode` or
|
||||
* `hold_lock_file_for_update_timeout_mode`, you can specify a suggested
|
||||
* mode for the underlying temporary file. Note that the file isn't
|
||||
* guaranteed to have this exact mode, since it may be limited by either
|
||||
* the umask, 'core.sharedRepository', or both. See `adjust_shared_perm`
|
||||
* for more.
|
||||
*
|
||||
* Error handling
|
||||
* --------------
|
||||
|
@ -156,12 +165,20 @@ struct lock_file {
|
|||
* file descriptor for writing to it, or -1 on error. If the file is
|
||||
* currently locked, retry with quadratic backoff for at least
|
||||
* timeout_ms milliseconds. If timeout_ms is 0, try exactly once; if
|
||||
* timeout_ms is -1, retry indefinitely. The flags argument and error
|
||||
* handling are described above.
|
||||
* timeout_ms is -1, retry indefinitely. The flags argument, error
|
||||
* handling, and mode are described above.
|
||||
*/
|
||||
int hold_lock_file_for_update_timeout(
|
||||
int hold_lock_file_for_update_timeout_mode(
|
||||
struct lock_file *lk, const char *path,
|
||||
int flags, long timeout_ms);
|
||||
int flags, long timeout_ms, int mode);
|
||||
|
||||
static inline int hold_lock_file_for_update_timeout(
|
||||
struct lock_file *lk, const char *path,
|
||||
int flags, long timeout_ms)
|
||||
{
|
||||
return hold_lock_file_for_update_timeout_mode(lk, path, flags,
|
||||
timeout_ms, 0666);
|
||||
}
|
||||
|
||||
/*
|
||||
* Attempt to create a lockfile for the file at `path` and return a
|
||||
|
@ -175,6 +192,13 @@ static inline int hold_lock_file_for_update(
|
|||
return hold_lock_file_for_update_timeout(lk, path, flags, 0);
|
||||
}
|
||||
|
||||
static inline int hold_lock_file_for_update_mode(
|
||||
struct lock_file *lk, const char *path,
|
||||
int flags, int mode)
|
||||
{
|
||||
return hold_lock_file_for_update_timeout_mode(lk, path, flags, 0, mode);
|
||||
}
|
||||
|
||||
/*
|
||||
* Return a nonzero value iff `lk` is currently locked.
|
||||
*/
|
||||
|
|
Загрузка…
Ссылка в новой задаче