gdb/testsuite/gdb.threads/hand-call-in-threads.c

   1 /* Test case for hand function calls in multi-threaded program.
   2
   3    Copyright 2008-2024 Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20 #include <pthread.h>
  21 #include <stdio.h>
  22 #include <stdlib.h>
  23 #include <time.h>
  24 #include <unistd.h>
  25
  26 #ifndef NR_THREADS
  27 #define NR_THREADS 4
  28 #endif
  29
  30 int thread_count;
  31
  32 pthread_mutex_t thread_count_mutex;
  33
  34 pthread_cond_t thread_count_condvar;
  35
  36 void
  37 incr_thread_count (void)
  38 {
  39   pthread_mutex_lock (&thread_count_mutex);
  40   ++thread_count;
  41   if (thread_count == NR_THREADS)
  42     pthread_cond_signal (&thread_count_condvar);
  43   pthread_mutex_unlock (&thread_count_mutex);
  44 }
  45
  46 void
  47 cond_wait (pthread_cond_t *cond, pthread_mutex_t *mut)
  48 {
  49   pthread_mutex_lock (mut);
  50   pthread_cond_wait (cond, mut);
  51   pthread_mutex_unlock (mut);
  52 }
  53
  54 void
  55 noreturn (void)
  56 {
  57   pthread_mutex_t mut;
  58   pthread_cond_t cond;
  59
  60   pthread_mutex_init (&mut, NULL);
  61   pthread_cond_init (&cond, NULL);
  62
  63   /* Wait for a condition that will never be signaled, so we effectively
  64      block the thread here.  */
  65   cond_wait (&cond, &mut);
  66 }
  67
  68 void *
  69 forever_pthread (void *unused)
  70 {
  71   incr_thread_count ();
  72   noreturn ();
  73 }
  74
  75 void
  76 hand_call (void)
  77 {
  78 }
  79
  80 /* Wait until all threads are running.  */
  81
  82 void
  83 wait_all_threads_running (void)
  84 {
  85   pthread_mutex_lock (&thread_count_mutex);
  86   if (thread_count == NR_THREADS)
  87     {
  88       pthread_mutex_unlock (&thread_count_mutex);
  89       return;
  90     }
  91   pthread_cond_wait (&thread_count_condvar, &thread_count_mutex);
  92   if (thread_count == NR_THREADS)
  93     {
  94       pthread_mutex_unlock (&thread_count_mutex);
  95       return;
  96     }
  97   pthread_mutex_unlock (&thread_count_mutex);
  98   printf ("failed waiting for all threads to start\n");
  99   abort ();
 100 }
 101
 102 /* Called when all threads are running.
 103    Easy place for a breakpoint.  */
 104
 105 void
 106 all_threads_running (void)
 107 {
 108 }
 109
 110 int
 111 main (void)
 112 {
 113   pthread_t forever[NR_THREADS];
 114   int i;
 115
 116   pthread_mutex_init (&thread_count_mutex, NULL);
 117   pthread_cond_init (&thread_count_condvar, NULL);
 118
 119   for (i = 0; i < NR_THREADS; ++i)
 120     pthread_create (&forever[i], NULL, forever_pthread, NULL);
 121
 122   wait_all_threads_running ();
 123   all_threads_running ();
 124
 125   return 0;
 126 }
 127