diff options
Diffstat (limited to 'lib')
-rw-r--r-- | lib/libc/stdio/_flock_stub.c | 15 |
1 files changed, 12 insertions, 3 deletions
diff --git a/lib/libc/stdio/_flock_stub.c b/lib/libc/stdio/_flock_stub.c index a77fad9..a947398 100644 --- a/lib/libc/stdio/_flock_stub.c +++ b/lib/libc/stdio/_flock_stub.c @@ -83,6 +83,7 @@ struct __file_lock { static int init_lock(FILE *fp) { + static pthread_mutex_t init_lock_mutex = PTHREAD_MUTEX_INITIALIZER; struct __file_lock *p; int ret; @@ -92,7 +93,16 @@ init_lock(FILE *fp) p->fl_mutex = PTHREAD_MUTEX_INITIALIZER; p->fl_owner = NULL; p->fl_count = 0; + if (pthread_mutex_lock(&init_lock_mutex) != 0) { + free(p); + return (-1); + } + if (fp->_lock != NULL) { /* lost the race */ + free(p); + return (0); + } fp->_lock = p; + pthread_mutex_unlock(&init_lock_mutex); ret = 0; } return (ret); @@ -142,8 +152,7 @@ _ftrylockfile(FILE *fp) * Check if this is a real file with a valid lock, creating * the lock if needed: */ - if ((fp->_file >= 0) && - ((fp->_lock != NULL) || (init_lock(fp) == 0))) { + if (((fp->_lock != NULL) || (init_lock(fp) == 0))) { if (fp->_lock->fl_owner == curthread) fp->_lock->fl_count++; /* @@ -171,7 +180,7 @@ _funlockfile(FILE *fp) * Check if this is a real file with a valid lock owned * by the current thread: */ - if ((fp->_file >= 0) && (fp->_lock != NULL) && + if ((fp->_lock != NULL) && (fp->_lock->fl_owner == curthread)) { /* * Check if this thread has locked the FILE |