tools-for-build/os-provides-wakebyaddr-test.c

   1 #include <windows.h>
   2
   3 int mutex_word = 0;
   4 int expect = 9;
   5
   6 DWORD waiter(void* arg) {
   7     mutex_word = expect = 2;
   8     return WaitOnAddress(&mutex_word, &expect, 4, 100); // .1 sec max
   9 }
  10 DWORD waker(void* arg) {
  11     mutex_word = 0;
  12     WakeByAddressSingle(&mutex_word);
  13     return 0;
  14 }
  15
  16 int main()
  17 {
  18     // Verify that WaitOnAddress returns right away if the mutex word has the wrong value.
  19     int result = WaitOnAddress(&mutex_word, &expect, 4, 500); // max = .5 sec
  20     if (!result) return 0; // what? shouldn't be an error to mismatch
  21
  22     // Try really waiting
  23     mutex_word = 9;
  24     result = WaitOnAddress(&mutex_word, &expect, 4, 20); // wait 20 millisec
  25     // expect a timeout
  26     if (!(result == 0 && GetLastError()==ERROR_TIMEOUT)) return 0;
  27
  28     // Simulate a lisp mutex being woken
  29     HANDLE hWaiter, hWaker;
  30     hWaiter = CreateThread(NULL, 0,
  31                            waiter, 0, /* function and argument */
  32                            0,  /* flags */
  33                            0); /* id */
  34
  35     hWaker = CreateThread(NULL, 0,
  36                           waker, 0, /* function and argument */
  37                           CREATE_SUSPENDED,  /* flags */
  38                           0); /* id */
  39
  40     for (;;) {
  41         // wait for the waiter to place itself into a wait state on the mutex
  42         if (mutex_word == 2) break;
  43         Sleep(10); // 10 millisec
  44     }
  45     // Give them some time to rendezvous
  46     ResumeThread(hWaker);
  47     WaitForSingleObject(hWaiter, 200); // .2 sec max
  48     if (mutex_word == 0) return 104;
  49     return 1;
  50 }