nsz Git - musl/blob - src/stdio/ftrylockfile.c

   1 #include "stdio_impl.h"
   2 #include "pthread_impl.h"
   3
   4 int ftrylockfile(FILE *f)
   5 {
   6         int tid = pthread_self()->tid;
   7         if (f->lock == tid) {
   8                 if (f->lockcount == INT_MAX)
   9                         return -1;
  10                 f->lockcount++;
  11                 return 0;
  12         }
  13         if (f->lock || a_cas(&f->lock, 0, tid))
  14                 return -1;
  15         f->lockcount = 1;
  16         return 0;
  17 }