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/* This testcase is part of GDB, the GNU debugger.
Copyright 2011-2019 Free Software Foundation, Inc.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include <sys/shm.h>
#include <sys/sem.h>
#include <sys/msg.h>
#include <stdio.h>
#include <pthread.h>
#include <arpa/inet.h>
#include <sys/socket.h>
#include <unistd.h>
#include <stdlib.h>
static pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;
/* System V IPC identifiers. */
static int shmid = -1, semid = -1, msqid = -1;
/* Delete any System V IPC resources that were allocated. */
static void
ipc_cleanup (void)
{
if (shmid >= 0)
shmctl (shmid, IPC_RMID, NULL);
if (semid >= 0)
semctl (semid, 0, IPC_RMID, NULL);
if (msqid >= 0)
msgctl (msqid, IPC_RMID, NULL);
}
void *
thread_proc (void *args)
{
pthread_mutex_lock (&mutex);
pthread_mutex_unlock (&mutex);
}
int
main (void)
{
const int flags = IPC_CREAT | 0666;
key_t shmkey = 3925, semkey = 7428, msgkey = 5294;
FILE *fd;
pthread_t thread;
struct sockaddr_in sock_addr;
int sock;
unsigned short port;
socklen_t size;
int status, try, retries = 1000;
atexit (ipc_cleanup);
for (try = 0; try < retries; ++try)
{
shmid = shmget (shmkey, 4096, flags | IPC_EXCL);
if (shmid >= 0)
break;
++shmkey;
}
if (shmid < 0)
{
printf ("Cannot create shared-memory region after %d tries.\n", retries);
return 1;
}
for (try = 0; try < retries; ++try)
{
semid = semget (semkey, 1, flags | IPC_EXCL);
if (semid >= 0)
break;
++semkey;
}
if (semid < 0)
{
printf ("Cannot create semaphore after %d tries.\n", retries);
return 1;
}
for (try = 0; try < retries; ++try)
{
msqid = msgget (msgkey, flags | IPC_EXCL);
if (msqid >= 0)
break;
++msgkey;
}
if (msqid < 0)
{
printf ("Cannot create message queue after %d tries.\n", retries);
return 1;
}
fd = fopen ("/dev/null", "r");
/* Lock the mutex to prevent the new thread from finishing immediately. */
pthread_mutex_lock (&mutex);
pthread_create (&thread, NULL, thread_proc, 0);
sock = socket (PF_INET, SOCK_STREAM, IPPROTO_TCP);
if (sock < 0)
{
printf ("Cannot create socket.\n");
return 1;
}
sock_addr.sin_family = AF_INET;
sock_addr.sin_port = 0; /* Bind to a free port. */
sock_addr.sin_addr.s_addr = htonl (INADDR_ANY);
status = bind (sock, (struct sockaddr *) &sock_addr, sizeof (sock_addr));
if (status < 0)
{
printf ("Cannot bind socket.\n");
return 1;
}
/* Find the assigned port number of the socket. */
size = sizeof (sock_addr);
status = getsockname (sock, (struct sockaddr *) &sock_addr, &size);
if (status < 0)
{
printf ("Cannot find name of socket.\n");
return 1;
}
port = ntohs (sock_addr.sin_port);
status = listen (sock, 1);
if (status < 0)
{
printf ("Cannot listen on socket.\n");
return 1;
}
/* Set breakpoint here. */
fclose (fd);
close (sock);
pthread_mutex_unlock (&mutex);
pthread_join (thread, NULL);
return 0;
}
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