1  /*
       2   * This file is part of attach-p-cmd strace test.
       3   *
       4   * Copyright (c) 2016-2021 Dmitry V. Levin <ldv@strace.io>
       5   * All rights reserved.
       6   *
       7   * SPDX-License-Identifier: GPL-2.0-or-later
       8   */
       9  
      10  #include "tests.h"
      11  #include <errno.h>
      12  #include <signal.h>
      13  #include <stdio.h>
      14  #include <stdlib.h>
      15  #include <sys/stat.h>
      16  #include <time.h>
      17  #include <unistd.h>
      18  #include "attach-p-cmd.h"
      19  
      20  static void
      21  wait_for_peer_invocation(void)
      22  {
      23  	/* create the lock directory */
      24  	if (mkdir(lockdir, 0700))
      25  		perror_msg_and_fail("mkdir: %s", lockdir);
      26  
      27  	/* wait for the lock directory to be removed by peer */
      28  	while (mkdir(lockdir, 0700)) {
      29  		if (EEXIST != errno)
      30  			perror_msg_and_fail("mkdir: %s", lockdir);
      31  	}
      32  
      33  	/* cleanup the lock directory */
      34  	if (rmdir(lockdir))
      35  		perror_msg_and_fail("rmdir: %s", lockdir);
      36  }
      37  
      38  static void
      39  wait_for_peer_termination(void)
      40  {
      41  	FILE *fp = fopen(pidfile, "r");
      42  	if (!fp)
      43  		perror_msg_and_fail("fopen: %s", pidfile);
      44  
      45  	pid_t pid;
      46  	if (fscanf(fp, "%d", &pid) < 0)
      47  		perror_msg_and_fail("fscanf: %s", pidfile);
      48  	if (pid < 0)
      49  		error_msg_and_fail("pid = %d", pid);
      50  
      51  	if (fclose(fp))
      52  		perror_msg_and_fail("fclose: %s", pidfile);
      53  
      54  	if (unlink(pidfile))
      55  		perror_msg_and_fail("unlink: %s", pidfile);
      56  
      57  	while (kill(pid, 0) == 0)
      58  		;
      59  }
      60  
      61  int
      62  main(void)
      63  {
      64  	wait_for_peer_invocation();
      65  	wait_for_peer_termination();
      66  
      67  	static const struct timespec ts = { .tv_nsec = 123456789 };
      68  	if (nanosleep(&ts, NULL))
      69  		perror_msg_and_fail("nanosleep");
      70  
      71  	static const char dir[] = "attach-p-cmd.test -p";
      72  	pid_t pid = getpid();
      73  	int rc = chdir(dir);
      74  
      75  	printf("%-5d chdir(\"%s\") = %s\n"
      76  	       "%-5d +++ exited with 0 +++\n",
      77  	       pid, dir, sprintrc(rc), pid);
      78  
      79  	return 0;
      80  }