text: // SPDX-License-Identifier: GPL-2.0-or-later
  /*
   *
   *   Copyright (c) International Business Machines Corp., 2001
   *	07/2001 Ported by John George
   *      04/2002 wjhuie sigset cleanups
   *      08/2007 Ricardo Salveti de Araujo <rsalveti@linux.vnet.ibm.com>
   */
  
  /*
   * DESCRIPTION
   *	Check the return value, and errnos of write(2)
   *	- when the file descriptor is invalid - EBADF
   *	- when the buf parameter is invalid - EFAULT
   *	- on an attempt to write to a pipe that is not open for reading - EPIPE
   */
  #include <sys/types.h>
  #include <sys/stat.h>
  #include <fcntl.h>
  #include <errno.h>
  #include <stdio.h>
  #include <stdlib.h>
  #include <sys/wait.h>
  #include <sys/mman.h>
  #include "tst_test.h"
  
  static int fd;
  static int inv_fd = -1;
  static char b[32];
  static char *buf = b;
  static char *bad_addr;
  static int pipefd[2];
  
  static struct tcase {
  	int *fd;
  	char **buf;
  	size_t size;
  	int exp_errno;
  } tcases[] = {
  	{&inv_fd, &buf, sizeof(buf), EBADF},
  	{&fd, &bad_addr, sizeof(buf), EFAULT},
  	{&pipefd[1], &buf, sizeof(buf), EPIPE},
  };
  
  static int sigpipe_cnt;
  
  static void sighandler(int sig)
  {
  	if (sig == SIGPIPE)
  		sigpipe_cnt++;
  }
  
  static void verify_write(unsigned int i)
  {
  	struct tcase *tc = &tcases[i];
  
  	sigpipe_cnt = 0;
  
  	TEST(write(*tc->fd, *tc->buf, tc->size));
  
  	if (TST_RET != -1) {
  		tst_res(TFAIL, "write() succeeded unexpectedly");
  		return;
  	}
  
  	if (TST_ERR != tc->exp_errno) {
  		tst_res(TFAIL | TTERRNO,
  			"write() failed unexpectedly, expected %s",
  			tst_strerrno(tc->exp_errno));
  		return;
  	}
  
  	if (tc->exp_errno == EPIPE && sigpipe_cnt != 1) {
  		tst_res(TFAIL, "sigpipe_cnt = %i", sigpipe_cnt);
  		return;
  	}
  
  	tst_res(TPASS | TTERRNO, "write() failed expectedly");
  }
  
  static void setup(void)
  {
  	fd = SAFE_OPEN("write_test", O_RDWR | O_CREAT, 0644);
  
  	bad_addr = SAFE_MMAP(0, 1, PROT_NONE,
  			MAP_PRIVATE | MAP_ANONYMOUS, 0, 0);
  
  	SAFE_PIPE(pipefd);
  	SAFE_CLOSE(pipefd[0]);
  
  	SAFE_SIGNAL(SIGPIPE, sighandler);
  }
  
  static void cleanup(void)
  {
  	if (fd > 0)
  		SAFE_CLOSE(fd);
  
  	SAFE_MUNMAP(bad_addr, 1);
  }
  
  static struct tst_test test = {
  	.needs_tmpdir = 1,
  	.setup = setup,
  	.cleanup = cleanup,
  	.test = verify_write,
  	.tcnt = ARRAY_SIZE(tcases),
  };
  