From 656edbf5781e4f0a78aad960c7ca18686e637fed Mon Sep 17 00:00:00 2001
From: Fufu Fang <fangfufu2003@gmail.com>
Date: Tue, 3 Sep 2019 14:59:30 +0100
Subject: [PATCH] improved error messages when mutex locking/unlocking fails

---
 src/util.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/src/util.c b/src/util.c
index d3adfbd..1986d75 100644
--- a/src/util.c
+++ b/src/util.c
@@ -42,8 +42,8 @@ void PTHREAD_MUTEX_UNLOCK(pthread_mutex_t *x)
     int i;
     i = pthread_mutex_unlock(x);
     if (i) {
-        fprintf(stderr, "pthread_mutex_unlock failed, %d, %s\n", i,
-        strerror(i));
+        fprintf(stderr, "thread %lu: pthread_mutex_unlock() failed, %d, %s\n",
+                pthread_self(), i, strerror(i));
         exit_failure();
     }
 }
@@ -53,8 +53,8 @@ void PTHREAD_MUTEX_LOCK(pthread_mutex_t *x)
     int i;
     i = pthread_mutex_lock(x);
     if (i) {
-        fprintf(stderr, "pthread_mutex_lock failed, %d, %s\n", i,
-        strerror(i));
+        fprintf(stderr, "thread %lu: pthread_mutex_lock() failed, %d, %s\n",
+                pthread_self(), i, strerror(i));
         exit_failure();
     }
 }