1*c9945492SAndroid Build Coastguard Worker #include "stdio_impl.h"
2*c9945492SAndroid Build Coastguard Worker #include "pthread_impl.h"
3*c9945492SAndroid Build Coastguard Worker
__lockfile(FILE * f)4*c9945492SAndroid Build Coastguard Worker int __lockfile(FILE *f)
5*c9945492SAndroid Build Coastguard Worker {
6*c9945492SAndroid Build Coastguard Worker int owner = f->lock, tid = __pthread_self()->tid;
7*c9945492SAndroid Build Coastguard Worker if ((owner & ~MAYBE_WAITERS) == tid)
8*c9945492SAndroid Build Coastguard Worker return 0;
9*c9945492SAndroid Build Coastguard Worker owner = a_cas(&f->lock, 0, tid);
10*c9945492SAndroid Build Coastguard Worker if (!owner) return 1;
11*c9945492SAndroid Build Coastguard Worker while ((owner = a_cas(&f->lock, 0, tid|MAYBE_WAITERS))) {
12*c9945492SAndroid Build Coastguard Worker if ((owner & MAYBE_WAITERS) ||
13*c9945492SAndroid Build Coastguard Worker a_cas(&f->lock, owner, owner|MAYBE_WAITERS)==owner)
14*c9945492SAndroid Build Coastguard Worker __futexwait(&f->lock, owner|MAYBE_WAITERS, 1);
15*c9945492SAndroid Build Coastguard Worker }
16*c9945492SAndroid Build Coastguard Worker return 1;
17*c9945492SAndroid Build Coastguard Worker }
18*c9945492SAndroid Build Coastguard Worker
__unlockfile(FILE * f)19*c9945492SAndroid Build Coastguard Worker void __unlockfile(FILE *f)
20*c9945492SAndroid Build Coastguard Worker {
21*c9945492SAndroid Build Coastguard Worker if (a_swap(&f->lock, 0) & MAYBE_WAITERS)
22*c9945492SAndroid Build Coastguard Worker __wake(&f->lock, 1, 1);
23*c9945492SAndroid Build Coastguard Worker }
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