fix false ownership of stdio FILEs due to tid reuse

[musl] / src / thread / __lock.c

diff --git a/src/thread/__lock.c b/src/thread/__lock.c
index 2f345ae..0874c04 100644 (file)
--- a/src/thread/__lock.c
+++ b/src/thread/__lock.c
@@ -2,11 +2,14 @@
 
 void __lock(volatile int *l)
 {
-       while (a_swap(l, 1)) __wait(l, l+1, 1, 1);
+       if (libc.threads_minus_1)
+               while (a_swap(l, 1)) __wait(l, l+1, 1, 1);
 }
 
 void __unlock(volatile int *l)
 {
-       a_store(l, 0);
-       if (l[1]) __wake(l, 1, 1);
+       if (l[0]) {
+               a_store(l, 0);
+               if (l[1]) __wake(l, 1, 1);
+       }
 }