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 <stdio.h>
      13  #include <sys/stat.h>
      14  #include <unistd.h>
      15  #include "attach-p-cmd.h"
      16  
      17  static void
      18  write_pidfile(const pid_t pid)
      19  {
      20  	FILE *fp = fopen(pidfile, "w");
      21  	if (!fp)
      22  		perror_msg_and_fail("fopen: %s", pidfile);
      23  
      24  	if (fprintf(fp, "%d", pid) < 0)
      25  		perror_msg_and_fail("fprintf: %s", pidfile);
      26  
      27  	if (fclose(fp))
      28  		perror_msg_and_fail("fclose: %s", pidfile);
      29  }
      30  
      31  static void
      32  wait_for_peer_invocation(void)
      33  {
      34  	/* wait for the lock directory to be created by peer */
      35  	while (rmdir(lockdir)) {
      36  		if (ENOENT != errno)
      37  			perror_msg_and_fail("rmdir: %s", lockdir);
      38  	}
      39  }
      40  
      41  int
      42  main(void)
      43  {
      44  	const pid_t pid = getpid();
      45  	write_pidfile(pid);
      46  
      47  	wait_for_peer_invocation();
      48  
      49  	static const char dir[] = "attach-p-cmd.test cmd";
      50  	int rc = chdir(dir);
      51  
      52  	printf("%-5d chdir(\"%s\") = %s\n"
      53  	       "%-5d +++ exited with 0 +++\n",
      54  	       pid, dir, sprintrc(rc), pid);
      55  
      56  	return 0;
      57  }