1 #include "stdio_impl.h" 2 #include "pthread_impl.h" 3 4 #ifdef __GNUC__ 5 __attribute__((__noinline__)) 6 #endif locking_getc(FILE * f)7static int locking_getc(FILE *f) 8 { 9 if (a_cas(&f->lock, 0, MAYBE_WAITERS-1)) __lockfile(f); 10 int c = getc_unlocked(f); 11 if (a_swap(&f->lock, 0) & MAYBE_WAITERS) 12 __wake(&f->lock, 1, 1); 13 return c; 14 } 15 do_getc(FILE * f)16static inline int do_getc(FILE *f) 17 { 18 int l = f->lock; 19 if (l < 0 || l && (l & ~MAYBE_WAITERS) == __pthread_self()->tid) 20 return getc_unlocked(f); 21 return locking_getc(f); 22 } 23