use pthread_cleanup to acquire and release lock

In chunk_prepare(), if multiple threads wait for acquiring f->lock,
and then pthread_cancel() is called, the waiting threads are never
canceled because pthread_mutex_lock() is not a cancellation point.
So, use pthread_cleanup_push/pop to release the lock.

1 files changed, 2 insertions, 2 deletions

diff --git a/src/file.c b/src/file.c
index 4edab42..55e95a5 100644
--- a/src/file.c
+++ b/src/file.c
@@ -554,7 +554,7 @@ int chunk_prepare(struct chunk *c, sftp_session sftp)
 	struct file *f = c->f;
 	int ret = 0;
 
-	lock_acquire(&f->lock); /* XXX: is always acquiring lock per-chunk heavy? */
+	LOCK_ACQUIRE_THREAD(&f->lock);
 	if (f->state == FILE_STATE_INIT) {
 		if (file_dst_prepare(f, f->dst_is_remote ? sftp : NULL) < 0) {
 			ret = -1;
@@ -565,7 +565,7 @@ int chunk_prepare(struct chunk *c, sftp_session sftp)
 	}
 
 out:
-	lock_release(&f->lock);
+	LOCK_RELEASE_THREAD();
 	return ret;
 }