[PATCH] erofs-utils: fix thread join loop in erofs_destroy_workqueue

[Nithurshen <nithurshen.dev@gmail.com>]

Currently, erofs_destroy_workqueue returns immediately if a single
pthread_join fails. This halts the teardown process, potentially
leaving orphaned threads and leaking the workqueue's mutexes and
worker array.

Refactor the joining logic to unconditionally join all worker
threads. Capture the first error encountered, continue joining the
remaining threads, and ensure all workqueue resources are properly
freed before returning the captured error.

Signed-off-by: Nithurshen <nithurshen.dev@gmail.com>
---
 lib/workqueue.c | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/lib/workqueue.c b/lib/workqueue.c
index 18ee0f9..23eb460 100644
--- a/lib/workqueue.c
+++ b/lib/workqueue.c
@@ -42,6 +42,8 @@ static void *worker_thread(void *arg)
 
 int erofs_destroy_workqueue(struct erofs_workqueue *wq)
 {
+	int err = 0;
+
 	if (!wq)
 		return -EINVAL;
 
@@ -53,15 +55,17 @@ int erofs_destroy_workqueue(struct erofs_workqueue *wq)
 	while (wq->nworker) {
 		int ret = -pthread_join(wq->workers[wq->nworker - 1], NULL);
 
-		if (ret)
-			return ret;
+		if (ret && !err)
+			err = ret;
+
 		--wq->nworker;
 	}
 	free(wq->workers);
 	pthread_mutex_destroy(&wq->lock);
 	pthread_cond_destroy(&wq->cond_empty);
 	pthread_cond_destroy(&wq->cond_full);
-	return 0;
+
+	return err;
 }
 
 int erofs_alloc_workqueue(struct erofs_workqueue *wq, unsigned int nworker,
-- 
2.51.0