1  #include <errno.h>
       2  #include <limits.h>
       3  #include <pthread.h>
       4  #include <stdio.h>
       5  #include <stdlib.h>
       6  #include <string.h>
       7  #include <unistd.h>
       8  #include <sys/mman.h>
       9  #include <sys/resource.h>
      10  
      11  static void use_stack (size_t needed);
      12  
      13  void (*use_stack_ptr) (size_t) = use_stack;
      14  
      15  static void
      16  use_stack (size_t needed)
      17  {
      18    size_t sz = sysconf (_SC_PAGESIZE);
      19    char *buf = alloca (sz);
      20    memset (buf, '\0', sz);
      21  
      22    if (needed > sz)
      23      use_stack_ptr (needed  - sz);
      24  }
      25  
      26  static void
      27  use_up_memory (void)
      28  {
      29    struct rlimit rl;
      30    getrlimit (RLIMIT_AS, &rl);
      31    rl.rlim_cur = 10 * 1024 * 1024;
      32    setrlimit (RLIMIT_AS, &rl);
      33  
      34    char *c;
      35    int PAGESIZE = getpagesize ();
      36    while (1)
      37      {
      38        c = mmap (NULL, PAGESIZE, PROT_NONE, MAP_ANON | MAP_PRIVATE, -1, 0);
      39        if (c == MAP_FAILED)
      40  	break;
      41      }
      42  }
      43  
      44  static void *
      45  child (void *arg)
      46  {
      47    sleep (1);
      48    return arg;
      49  }
      50  
      51  static int
      52  do_test (void)
      53  {
      54    int err;
      55    pthread_t tid;
      56  
      57    /* Allocate the memory needed for the stack.  */
      58  #ifdef PTHREAD_STACK_MIN
      59    use_stack_ptr (PTHREAD_STACK_MIN);
      60  #else
      61    use_stack_ptr (4 * getpagesize ());
      62  #endif
      63  
      64    use_up_memory ();
      65  
      66    err = pthread_create (&tid, NULL, child, NULL);
      67    if (err != 0)
      68      {
      69        printf ("pthread_create returns %d: %s\n", err,
      70  	      err == EAGAIN ? "OK" : "FAIL");
      71        return err != EAGAIN;
      72      }
      73  
      74    /* We did not fail to allocate memory despite the preparation.  Oh well.  */
      75    return 0;
      76  }
      77  
      78  #define TEST_FUNCTION do_test ()
      79  #include "../test-skeleton.c"