fix logic error in fread

[musl] / src / stdio / __lockfile.c

diff --git a/src/stdio/__lockfile.c b/src/stdio/__lockfile.c
index e4320f0..66a4d26 100644 (file)
--- a/src/stdio/__lockfile.c
+++ b/src/stdio/__lockfile.c
@@ -3,17 +3,18 @@
 
 void __lockfile(FILE *f)
 {
-       int spins;
-       if (f->owner < 0) return;
-       if (f->owner && f->owner == __pthread_self()->tid) {
+       int spins=10000;
+       int tid;
+
+       if (f->lock < 0) return;
+       tid = __pthread_self()->tid;
+       if (f->lock == tid) {
                while (f->lockcount == INT_MAX);
                f->lockcount++;
                return;
        }
-       spins = 100000;
-       while (a_swap(&f->lock, 1))
+       while (a_cas(&f->lock, 0, tid))
                if (spins) spins--, a_spin();
-               else syscall(SYS_sched_yield);
-       f->owner = __pthread_self()->tid;
+               else __syscall(SYS_sched_yield);
        f->lockcount = 1;
 }