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 (!libc.lockfile) libc.lockfile = __lockfile;
   8         if (f->lock == tid) {
   9                 if (f->lockcount == INT_MAX)
  10                         return -1;
  11                 f->lockcount++;
  12                 return 0;
  13         }
  14         if (f->lock || a_cas(&f->lock, 0, tid))
  15                 return -1;
  16         f->lockcount = 1;
  17         return 0;
  18 }