From 5e635e396020cc08bc21a3e67c20c5294d6d13fd Mon Sep 17 00:00:00 2001 From: Junio C Hamano Date: Sat, 21 Apr 2007 03:11:10 -0700 Subject: [PATCH] lockfile: record the primary process. The usual process flow is the main process opens and holds the lock to the index, does its thing, perhaps spawning children during the course, and then writes the resulting index out by releaseing the lock. However, the lockfile interface uses atexit(3) to clean it up, without regard to who actually created the lock. This typically leads to a confusing behaviour of lock being released too early when the child exits, and then the parent process when it calls commit_lockfile() finds that it cannot unlock it. This fixes the problem by recording who created and holds the lock, and upon atexit(3) handler, child simply ignores the lockfile the parent created. Signed-off-by: Junio C Hamano --- cache.h | 1 + lockfile.c | 6 +++++- 2 files changed, 6 insertions(+), 1 deletion(-) diff --git a/cache.h b/cache.h index 8c804cb6e..faddaf650 100644 --- a/cache.h +++ b/cache.h @@ -209,6 +209,7 @@ extern int refresh_cache(unsigned int flags); struct lock_file { struct lock_file *next; + pid_t owner; char on_list; char filename[PATH_MAX]; }; diff --git a/lockfile.c b/lockfile.c index bed6b21da..23db35aff 100644 --- a/lockfile.c +++ b/lockfile.c @@ -8,8 +8,11 @@ static const char *alternate_index_output; static void remove_lock_file(void) { + pid_t me = getpid(); + while (lock_file_list) { - if (lock_file_list->filename[0]) + if (lock_file_list->owner == me && + lock_file_list->filename[0]) unlink(lock_file_list->filename); lock_file_list = lock_file_list->next; } @@ -28,6 +31,7 @@ static int lock_file(struct lock_file *lk, const char *path) sprintf(lk->filename, "%s.lock", path); fd = open(lk->filename, O_RDWR | O_CREAT | O_EXCL, 0666); if (0 <= fd) { + lk->owner = getpid(); if (!lk->on_list) { lk->next = lock_file_list; lock_file_list = lk; -- 2.30.2