pthreads/tests/pthread_atfork_test.c

   1 #include <assert.h>
   2 #include <pthread.h>
   3 #include <sys/types.h>
   4 #include <sys/wait.h>
   5
   6 /*
   7  * Parent and child handlers are called in the order they were registered
   8  * prepare handlers are called in reverse order. The non-commutative
   9  * operations will ensure that we are calling them in the proper order.
  10  */
  11
  12 static int parentval = 0;
  13 static int childval = 0;
  14
  15 static void prepare1(void)
  16 {
  17         parentval *= 2;
  18 }
  19
  20 static void prepare2(void)
  21 {
  22         parentval = 3;
  23 }
  24
  25 static void parent1(void)
  26 {
  27         parentval += 4;
  28 }
  29
  30 static void parent2(void)
  31 {
  32         parentval *= 3;
  33 }
  34
  35 static void child1(void)
  36 {
  37         childval = 5;
  38 }
  39
  40 static void child2(void)
  41 {
  42         childval *= 3;
  43 }
  44
  45 int
  46 main(void)
  47 {
  48         pid_t pid, child;
  49         int status;
  50
  51         assert(!pthread_atfork(prepare1, parent1, child1));
  52         assert(!pthread_atfork(prepare2, parent2, child2));
  53         pid = fork();
  54         assert(pid >= 0);
  55         if (pid == 0) {
  56                 _exit(childval);
  57         } else {
  58                 child = waitpid(pid, &status, 0);
  59                 assert(child == pid);
  60                 assert(WIFEXITED(status));
  61                 assert(WEXITSTATUS(status) == 15);
  62                 assert(parentval == 30);
  63         }
  64         return 0;
  65 }