gdb/testsuite/gdb.threads/fork-plus-threads.c

   1 /* This testcase is part of GDB, the GNU debugger.
   2
   3    Copyright 2015-2023 Free Software Foundation, Inc.
   4
   5    This program is free software; you can redistribute it and/or modify
   6    it under the terms of the GNU General Public License as published by
   7    the Free Software Foundation; either version 3 of the License, or
   8    (at your option) any later version.
   9
  10    This program is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13    GNU General Public License for more details.
  14
  15    You should have received a copy of the GNU General Public License
  16    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  17
  18 #include <assert.h>
  19 #include <pthread.h>
  20 #include <unistd.h>
  21 #include <stdio.h>
  22 #include <sys/types.h>
  23 #include <sys/wait.h>
  24
  25
  26 /* Number of times the main process forks.  */
  27 #define NFORKS 10
  28
  29 /* Number of threads by each fork child.  */
  30 #define NTHREADS 10
  31
  32 static void *
  33 thread_func (void *arg)
  34 {
  35   /* Empty.  */
  36   return NULL;
  37 }
  38
  39 static void
  40 fork_child (void)
  41 {
  42   pthread_t threads[NTHREADS];
  43   int i;
  44   int ret;
  45
  46   for (i = 0; i < NTHREADS; i++)
  47     {
  48       ret = pthread_create (&threads[i], NULL, thread_func, NULL);
  49       assert (ret == 0);
  50     }
  51
  52   for (i = 0; i < NTHREADS; i++)
  53     {
  54       ret = pthread_join (threads[i], NULL);
  55       assert (ret == 0);
  56     }
  57 }
  58
  59 int
  60 main (void)
  61 {
  62   pid_t childs[NFORKS];
  63   int i;
  64   int status;
  65   int num_exited = 0;
  66
  67   /* Don't run forever if the wait loop below gets stuck.  */
  68   alarm (180);
  69
  70   for (i = 0; i < NFORKS; i++)
  71     {
  72       pid_t pid;
  73
  74       pid = fork ();
  75
  76       if (pid > 0)
  77         {
  78           /* Parent.  */
  79           childs[i] = pid;
  80         }
  81       else if (pid == 0)
  82         {
  83           /* Child.  */
  84           fork_child ();
  85           return 0;
  86         }
  87       else
  88         {
  89           perror ("fork");
  90           return 1;
  91         }
  92     }
  93
  94   while (num_exited != NFORKS)
  95     {
  96       pid_t pid = wait (&status);
  97
  98       if (pid == -1)
  99         {
 100           perror ("wait");
 101           return 1;
 102         }
 103
 104       if (WIFEXITED (status))
 105         {
 106           num_exited++;
 107         }
 108       else
 109         {
 110           printf ("Hmm, unexpected wait status 0x%x from child %d\n", status,
 111                   pid);
 112         }
 113     }
 114
 115   return 0;
 116 }