text: /*-
   * Copyright (c) 2005 Robert N. M. Watson
   * All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in the
   *    documentation and/or other materials provided with the distribution.
   *
   * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
   * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
   * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   * SUCH DAMAGE.
   *
   * $FreeBSD$
   */
  
  #include <sys/types.h>
  #include <sys/event.h>
  #include <sys/ioctl.h>
  #include <sys/select.h>
  #include <sys/stat.h>
  #include <sys/time.h>
  
  #include <err.h>
  #include <errno.h>
  #include <fcntl.h>
  #include <limits.h>
  #include <poll.h>
  #include <signal.h>
  #include <stdio.h>
  #include <stdlib.h>
  #include <string.h>
  #include <unistd.h>
  
  /*
   * Regression test to exercise POSIX fifo I/O.
   *
   * We test a number of aspect of behavior, including:
   *
   * - If there's no data to read, then for blocking fifos, we block, and for
   *   non-blocking, we return EAGAIN.
   *
   * - If we write ten bytes, ten bytes can be read, and they're the same
   *   bytes, in the same order.
   *
   * - If we write two batches of five bytes, we can read the same ten bytes in
   *   one read of ten bytes.
   *
   * - If we write ten bytes, we can read the same ten bytes in two reads of
   *   five bytes each.
   *
   * - If we over-fill a buffer (by writing 512k, which we take to be a large
   *   number above default buffer sizes), we block if there is no reader.
   *
   * - That once 512k (ish) is read from the other end, the blocked writer
   *   wakes up.
   *
   * - When a fifo is empty, poll, select, kqueue, and fionread report it is
   *   writable but not readable.
   *
   * - When a fifo has data in it, poll, select, and kqueue report that it is
   *   writable.
   *
   * - XXX: blocked reader semantics?
   *
   * - XXX: event behavior on remote close?
   *
   * Although behavior of O_RDWR isn't defined for fifos by POSIX, we expect
   * "reasonable" behavior, and run some additional tests relating to event
   * management on O_RDWR fifo descriptors.
   */
  
  #define	KQUEUE_MAX_EVENT	8
  
  /*
   * All activity occurs within a temporary directory created early in the
   * test.
   */
  static char	temp_dir[PATH_MAX];
  
  static void __unused
  atexit_temp_dir(void)
  {
  
  	rmdir(temp_dir);
  }
  
  static void
  makefifo(const char *fifoname, const char *testname)
  {
  
  	if (mkfifo(fifoname, 0700) < 0)
  		err(-1, "%s: makefifo: mkfifo: %s", testname, fifoname);
  }
  
  static void
  cleanfifo2(const char *fifoname, int fd1, int fd2)
  {
  
  	if (fd1 != -1)
  		close(fd1);
  	if (fd2 != -1)
  		close(fd2);
  	(void)unlink(fifoname);
  }
  
  static void
  cleanfifo3(const char *fifoname, int fd1, int fd2, int fd3)
  {
  
  	if (fd3 != -1)
  		close(fd3);
  	cleanfifo2(fifoname, fd1, fd2);
  }
  
  /*
   * Open two different file descriptors for a fifo: one read, one write.  Do
   * so using non-blocking opens in order to avoid deadlocking the process.
   */
  static int
  openfifo(const char *fifoname, int *reader_fdp, int *writer_fdp)
  {
  	int error, fd1, fd2;
  
  	fd1 = open(fifoname, O_RDONLY | O_NONBLOCK);
  	if (fd1 < 0)
  		return (-1);
  	fd2 = open(fifoname, O_WRONLY | O_NONBLOCK);
  	if (fd2 < 0) {
  		error = errno;
  		close(fd1);
  		errno = error;
  		return (-1);
  	}
  	*reader_fdp = fd1;
  	*writer_fdp = fd2;
  
  	return (0);
  }
  
  /*
   * Open one file descriptor for the fifo, supporting both read and write.
   */
  static int
  openfifo_rw(const char *fifoname, int *fdp)
  {
  	int fd;
  
  	fd = open(fifoname, O_RDWR);
  	if (fd < 0)
  		return (-1);
  	*fdp = fd;
  
  	return (0);
  }
  
  static int
  set_nonblocking(int fd, const char *testname)
  {
  	int flags;
  
  	flags = fcntl(fd, F_GETFL);
  	if (flags < 0) {
  		warn("%s: fcntl(fd, F_GETFL)", testname);
  		return(-1);
  	}
  
  	flags |= O_NONBLOCK;
  
  	if (fcntl(fd, F_SETFL, flags) < 0) {
  		warn("%s: fcntl(fd, 0x%x)", testname, flags);
  		return (-1);
  	}
  
  	return (0);
  }
  
  static int
  set_blocking(int fd, const char *testname)
  {
  	int flags;
  
  	flags = fcntl(fd, F_GETFL);
  	if (flags < 0) {
  		warn("%s: fcntl(fd, F_GETFL)", testname);
  		return(-1);
  	}
  
  	flags &= ~O_NONBLOCK;
  
  	if (fcntl(fd, F_SETFL, flags) < 0) {
  		warn("%s: fcntl(fd, 0x%x)", testname, flags);
  		return (-1);
  	}
  
  	return (0);
  }
  
  /*
   * Drain a file descriptor (fifo) of any readable data.  Note: resets the
   * blocking state.
   */
  static int
  drain_fd(int fd, const char *testname)
  {
  	ssize_t len;
  	u_char ch;
  
  	if (set_nonblocking(fd, testname) < 0)
  		return (-1);
  
  	while ((len = read(fd, &ch, sizeof(ch))) > 0);
  	if (len < 0) {
  		switch (errno) {
  		case EAGAIN:
  			return (0);
  		default:
  			warn("%s: drain_fd: read", testname);
  			return (-1);
  		}
  	}
  	warn("%s: drain_fd: read: returned 0 bytes", testname);
  	return (-1);
  }
  
  /*
   * Simple I/O test: write ten integers, and make sure we get back the same
   * integers in the same order.  This assumes a minimum fifo buffer > 10
   * bytes in order to not block and deadlock.
   */
  static void
  test_simpleio(void)
  {
  	int i, reader_fd, writer_fd;
  	u_char buffer[10];
  	ssize_t len;
  
  	makefifo("testfifo", __func__);
  	if (openfifo("testfifo", &reader_fd, &writer_fd)
  	    < 0) {
  		warn("test_simpleio: openfifo: testfifo");
  		cleanfifo2("testfifo", -1, -1);
  		exit(-1);
  	}
  
  	for (i = 0; i < 10; i++)
  		buffer[i] = i;
  
  	len = write(writer_fd, (char *)buffer, sizeof(buffer));
  	if (len < 0) {
  		warn("test_simpleio: write");
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  	if (len != sizeof(buffer)) {
  		warnx("test_simplio: tried %zu but wrote %zd", sizeof(buffer),
  		    len);
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  
  	len = read(reader_fd, (char *)buffer, sizeof(buffer));
  	if (len < 0) {
  		warn("test_simpleio: read");
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  	if (len != sizeof(buffer)) {
  		warnx("test_simpleio: tried %zu but read %zd", sizeof(buffer),
  		    len);
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  	for (i = 0; i < 10; i++) {
  		if (buffer[i] == i)
  			continue;
  		warnx("test_simpleio: write byte %d as 0x%02x, but read "
  		    "0x%02x", i, i, buffer[i]);
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  
  	cleanfifo2("testfifo", reader_fd, writer_fd);
  }
  
  static volatile int alarm_fired;
  /*
   * Non-destructive SIGALRM handler.
   */
  static void
  sigalarm(int signum __unused)
  {
  
  	alarm_fired = 1;
  }
  
  /*
   * Wrapper function for write, which uses a timer to interrupt any blocking.
   * Because we can't reliably detect EINTR for blocking I/O, we also track
   * whether or not our timeout fired.
   */
  static int __unused
  timed_write(int fd, void *data, size_t len, ssize_t *written_lenp,
      int timeout, int *timedoutp, const char *testname)
  {
  	struct sigaction act, oact;
  	ssize_t written_len;
  	int error;
  
  	alarm_fired = 0;
  	bzero(&act, sizeof(oact));
  	act.sa_handler = sigalarm;
  	if (sigaction(SIGALRM, &act, &oact) < 0) {
  	 	warn("%s: timed_write: sigaction", testname);
  		return (-1);
  	}
  	alarm(timeout);
  	written_len = write(fd, data, len);
  	error = errno;
  	alarm(0);
  	if (sigaction(SIGALRM, &oact, NULL) < 0) {
  	 	warn("%s: timed_write: sigaction", testname);
  		return (-1);
  	}
  	if (alarm_fired)
  		*timedoutp = 1;
  	else
  		*timedoutp = 0;
  
  	errno = error;
  	if (written_len < 0)
  		return (-1);
  	*written_lenp = written_len;
  	return (0);
  }
  
  /*
   * Wrapper function for read, which uses a timer to interrupt any blocking.
   * Because we can't reliably detect EINTR for blocking I/O, we also track
   * whether or not our timeout fired.
   */
  static int
  timed_read(int fd, void *data, size_t len, ssize_t *read_lenp,
      int timeout, int *timedoutp, const char *testname)
  {
  	struct sigaction act, oact;
  	ssize_t read_len;
  	int error;
  
  	alarm_fired = 0;
  	bzero(&act, sizeof(oact));
  	act.sa_handler = sigalarm;
  	if (sigaction(SIGALRM, &act, &oact) < 0) {
  	 	warn("%s: timed_write: sigaction", testname);
  		return (-1);
  	}
  	alarm(timeout);
  	read_len = read(fd, data, len);
  	error = errno;
  	alarm(0);
  	if (sigaction(SIGALRM, &oact, NULL) < 0) {
  	 	warn("%s: timed_write: sigaction", testname);
  		return (-1);
  	}
  	if (alarm_fired)
  		*timedoutp = 1;
  	else
  		*timedoutp = 0;
  
  	errno = error;
  	if (read_len < 0)
  		return (-1);
  	*read_lenp = read_len;
  	return (0);
  }
  
  /*
   * This test operates on blocking and non-blocking fifo file descriptors, in
   * order to determine whether they block at good moments or not.  By good we
   * mean: don't block for non-blocking sockets, and do block for blocking
   * ones, assuming there isn't I/O buffer to satisfy the request.
   *
   * We use a timeout of 5 seconds, concluding that in 5 seconds either all I/O
   * that can take place will, and that if we reach the end of the timeout,
   * then blocking has occurred.
   *
   * We assume that the buffer size on a fifo is <512K, and as such, that
   * writing that much data without an active reader will result in blocking.
   */
  static void
  test_blocking_read_empty(void)
  {
  	int reader_fd, ret, timedout, writer_fd;
  	ssize_t len;
  	u_char ch;
  
  	makefifo("testfifo", __func__);
  	if (openfifo("testfifo", &reader_fd, &writer_fd)
  	    < 0) {
  		warn("test_blocking_read_empty: openfifo: testfifo");
  		cleanfifo2("testfifo", -1, -1);
  		exit(-1);
  	}
  
  	/*
  	 * Read one byte from an empty blocking fifo, block as there is no
  	 * data.
  	 */
  	if (set_blocking(reader_fd, __func__) < 0) {
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  
  	ret = timed_read(reader_fd, &ch, sizeof(ch), &len, 5, &timedout,
  	    __func__);
  	if (ret != -1) {
  		warnx("test_blocking_read_empty: timed_read: returned "
  		    "success");
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  	if (errno != EINTR) {
  		warn("test_blocking_read_empty: timed_read");
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  
  	/*
  	 * Read one byte from an empty non-blocking fifo, return EAGAIN as
  	 * there is no data.
  	 */
  	if (set_nonblocking(reader_fd, __func__) < 0) {
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  
  	ret = timed_read(reader_fd, &ch, sizeof(ch), &len, 5, &timedout,
  	    __func__);
  	if (ret != -1) {
  		warnx("test_blocking_read_empty: timed_read: returned "
  		    "success");
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  	if (errno != EAGAIN) {
  		warn("test_blocking_read_empty: timed_read");
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  
  	cleanfifo2("testfifo", reader_fd, writer_fd);
  }
  
  /*
   * Write one byte to an empty fifo, then try to read one byte and make sure
   * we don't block in either the write or the read.  This tests both for
   * improper blocking in the send and receive code.
   */
  static void
  test_blocking_one_byte(void)
  {
  	int reader_fd, ret, timedout, writer_fd;
  	ssize_t len;
  	u_char ch;
  
  	makefifo("testfifo", __func__);
  	if (openfifo("testfifo", &reader_fd, &writer_fd) < 0) {
  		warn("test_blocking: openfifo: testfifo");
  		cleanfifo2("testfifo", -1, -1);
  		exit(-1);
  	}
  
  	if (set_blocking(writer_fd, __func__) < 0) {
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  	if (set_blocking(reader_fd, __func__) < 0) {
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  
  	ch = 0xfe;
  	ret = timed_write(writer_fd, &ch, sizeof(ch), &len, 5, &timedout,
  	    __func__);
  	if (ret < 0) {
  		warn("test_blocking_one_byte: timed_write");
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  	if (len != sizeof(ch)) {
  		warnx("test_blocking_one_byte: timed_write: tried to write "
  		    "%zu, wrote %zd", sizeof(ch), len);
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  
  	ch = 0xab;
  	ret = timed_read(reader_fd, &ch, sizeof(ch), &len, 5, &timedout,
  	    __func__);
  	if (ret < 0) {
  		warn("test_blocking_one_byte: timed_read");
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  	if (len != sizeof(ch)) {
  		warnx("test_blocking_one_byte: timed_read: wanted %zu, "
  		    "read %zd", sizeof(ch), len);
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  	if (ch != 0xfe) {
  		warnx("test_blocking_one_byte: timed_read: expected to read "
  		    "0x%02x, read 0x%02x", 0xfe, ch);
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  
  	cleanfifo2("testfifo", reader_fd, writer_fd);
  }
  
  /*
   * Write one byte to an empty fifo, then try to read one byte and make sure
   * we don't get back EAGAIN.
   */
  static void
  test_nonblocking_one_byte(void)
  {
  	int reader_fd, ret, timedout, writer_fd;
  	ssize_t len;
  	u_char ch;
  
  	makefifo("testfifo", __func__);
  	if (openfifo("testfifo", &reader_fd, &writer_fd) < 0) {
  		warn("test_nonblocking: openfifo: testfifo");
  		cleanfifo2("testfifo", -1, -1);
  		exit(-1);
  	}
  
  	if (set_nonblocking(reader_fd, __func__) < 0) {
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  
  	ch = 0xfe;
  	ret = timed_write(writer_fd, &ch, sizeof(ch), &len, 5, &timedout,
  	    __func__);
  	if (ret < 0) {
  		warn("test_nonblocking_one_byte: timed_write");
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  	if (len != sizeof(ch)) {
  		warnx("test_nonblocking_one_byte: timed_write: tried to write "
  		    "%zu, wrote %zd", sizeof(ch), len);
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  
  	ch = 0xab;
  	ret = timed_read(reader_fd, &ch, sizeof(ch), &len, 5, &timedout,
  	    __func__);
  	if (ret < 0) {
  		warn("test_nonblocking_one_byte: timed_read");
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  	if (len != sizeof(ch)) {
  		warnx("test_nonblocking_one_byte: timed_read: wanted %zu, read "
  		    "%zd", sizeof(ch), len);
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  	if (ch != 0xfe) {
  		warnx("test_nonblocking_one_byte: timed_read: expected to read "
  		    "0x%02x, read 0x%02x", 0xfe, ch);
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  
  	cleanfifo2("testfifo", reader_fd, writer_fd);
  }
  
  /*
   * First of two test cases involving a 512K buffer: write the buffer into a
   * blocking file descriptor.  We'd like to know it blocks, but the closest we
   * can get is to see if SIGALRM fired during the I/O resulting in a partial
   * write.
   */
  static void
  test_blocking_partial_write(void)
  {
  	int reader_fd, ret, timedout, writer_fd;
  	u_char *buffer;
  	ssize_t len;
  
  	makefifo("testfifo", __func__);
  	if (openfifo("testfifo", &reader_fd, &writer_fd) < 0) {
  		warn("test_blocking_partial_write: openfifo: testfifo");
  		cleanfifo2("testfifo", -1, -1);
  		exit(-1);
  	}
  
  	if (set_blocking(writer_fd, __func__) < 0) {
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  
  	buffer = malloc(512*1024);
  	if (buffer == NULL) {
  		warn("test_blocking_partial_write: malloc");
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  	bzero(buffer, 512*1024);
  
  	ret = timed_write(writer_fd, buffer, 512*1024, &len, 5, &timedout,
  	    __func__);
  	if (ret < 0) {
  		warn("test_blocking_partial_write: timed_write");
  		free(buffer);
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  
  	if (!timedout) {
  		warnx("test_blocking_partial_write: timed_write: blocking "
  		    "socket didn't time out");
  		free(buffer);
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  
  	free(buffer);
  
  	if (drain_fd(reader_fd, __func__) < 0) {
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  
  	cleanfifo2("testfifo", reader_fd, writer_fd);
  }
  
  /*
   * Write a 512K buffer to an empty fifo using a non-blocking file descriptor,
   * and make sure it doesn't block.
   */
  static void
  test_nonblocking_partial_write(void)
  {
  	int reader_fd, ret, timedout, writer_fd;
  	u_char *buffer;
  	ssize_t len;
  
  	makefifo("testfifo", __func__);
  	if (openfifo("testfifo", &reader_fd, &writer_fd) < 0) {
  		warn("test_blocking_partial_write: openfifo: testfifo");
  		cleanfifo2("testfifo", -1, -1);
  		exit(-1);
  	}
  
  	if (set_nonblocking(writer_fd, __func__) < 0) {
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  
  	buffer = malloc(512*1024);
  	if (buffer == NULL) {
  		warn("test_blocking_partial_write: malloc");
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  	bzero(buffer, 512*1024);
  
  	ret = timed_write(writer_fd, buffer, 512*1024, &len, 5, &timedout,
  	    __func__);
  	if (ret < 0) {
  		warn("test_blocking_partial_write: timed_write");
  		free(buffer);
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  
  	if (timedout) {
  		warnx("test_blocking_partial_write: timed_write: "
  		    "non-blocking socket timed out");
  		free(buffer);
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  
  	if (len == 0 || len >= 512*1024) {
  		warnx("test_blocking_partial_write: timed_write: requested "
  		    "%d, sent %zd", 512*1024, len);
  		free(buffer);
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  
  	free(buffer);
  
  	if (drain_fd(reader_fd, __func__) < 0) {
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  
  	cleanfifo2("testfifo", reader_fd, writer_fd);
  }
  
  /*
   * test_coalesce_big_read() verifies that data mingles in the fifo across
   * message boundaries by performing two small writes, then a bigger read
   * that should return data from both writes.
   */
  static void
  test_coalesce_big_read(void)
  {
  	int i, reader_fd, writer_fd;
  	u_char buffer[10];
  	ssize_t len;
  
  	makefifo("testfifo", __func__);
  	if (openfifo("testfifo", &reader_fd, &writer_fd) < 0) {
  		warn("test_coalesce_big_read: openfifo: testfifo");
  		cleanfifo2("testfifo", -1, -1);
  		exit(-1);
  	}
  
  	/* Write five, write five, read ten. */
  	for (i = 0; i < 10; i++)
  		buffer[i] = i;
  
  	len = write(writer_fd, buffer, 5);
  	if (len < 0) {
  		warn("test_coalesce_big_read: write 5");
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  	if (len != 5) {
  		warnx("test_coalesce_big_read: write 5 wrote %zd", len);
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  
  	len = write(writer_fd, buffer + 5, 5);
  	if (len < 0) {
  		warn("test_coalesce_big_read: write 5");
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  	if (len != 5) {
  		warnx("test_coalesce_big_read: write 5 wrote %zd", len);
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  
  	len = read(reader_fd, buffer, 10);
  	if (len < 0) {
  		warn("test_coalesce_big_read: read 10");
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  	if (len != 10) {
  		warnx("test_coalesce_big_read: read 10 read %zd", len);
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  
  	for (i = 0; i < 10; i++) {
  		if (buffer[i] == i)
  			continue;
  		warnx("test_coalesce_big_read: expected to read 0x%02x, "
  		    "read 0x%02x", i, buffer[i]);
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  
  	cleanfifo2("testfifo", -1, -1);
  }
  
  /*
   * test_coalesce_big_write() verifies that data mingles in the fifo across
   * message boundaries by performing one big write, then two smaller reads
   * that should return sequential elements of data from the write.
   */
  static void
  test_coalesce_big_write(void)
  {
  	int i, reader_fd, writer_fd;
  	u_char buffer[10];
  	ssize_t len;
  
  	makefifo("testfifo", __func__);
  	if (openfifo("testfifo", &reader_fd, &writer_fd) < 0) {
  		warn("test_coalesce_big_write: openfifo: testfifo");
  		cleanfifo2("testfifo", -1, -1);
  		exit(-1);
  	}
  
  	/* Write ten, read five, read five. */
  	for (i = 0; i < 10; i++)
  		buffer[i] = i;
  
  	len = write(writer_fd, buffer, 10);
  	if (len < 0) {
  		warn("test_coalesce_big_write: write 10");
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  	if (len != 10) {
  		warnx("test_coalesce_big_write: write 10 wrote %zd", len);
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  
  	len = read(reader_fd, buffer, 5);
  	if (len < 0) {
  		warn("test_coalesce_big_write: read 5");
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  	if (len != 5) {
  		warnx("test_coalesce_big_write: read 5 read %zd", len);
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  
  	len = read(reader_fd, buffer + 5, 5);
  	if (len < 0) {
  		warn("test_coalesce_big_write: read 5");
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  	if (len != 5) {
  		warnx("test_coalesce_big_write: read 5 read %zd", len);
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  
  	for (i = 0; i < 10; i++) {
  		if (buffer[i] == i)
  			continue;
  		warnx("test_coalesce_big_write: expected to read 0x%02x, "
  		    "read 0x%02x", i, buffer[i]);
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  
  	cleanfifo2("testfifo", -1, -1);
  }
  
  static int
  poll_status(int fd, int *readable, int *writable, int *exception,
      const char *testname)
  {	
  	struct pollfd fds[1];
  
  	fds[0].fd = fd;
  	fds[0].events = POLLIN | POLLOUT | POLLERR;
  	fds[0].revents = 0;
  
  	if (poll(fds, 1, 0) < 0) {
  		warn("%s: poll", testname);
  		return (-1);
  	}
  	*readable = (fds[0].revents & POLLIN) ? 1 : 0;
  	*writable = (fds[0].revents & POLLOUT) ? 1 : 0;
  	*exception = (fds[0].revents & POLLERR) ? 1 : 0;
  	return (0);
  }
  
  static int
  select_status(int fd, int *readable, int *writable, int *exception,
      const char *testname)
  {
  	struct fd_set readfds, writefds, exceptfds;
  	struct timeval timeout;
  
  	FD_ZERO(&readfds);
  	FD_ZERO(&writefds);
  	FD_ZERO(&exceptfds);
  	FD_SET(fd, &readfds);
  	FD_SET(fd, &writefds);
  	FD_SET(fd, &exceptfds);
  	timeout.tv_sec = 0;
  	timeout.tv_usec = 0;
  	if (select(fd+1, &readfds, &writefds, &exceptfds, &timeout) < 0) {
  		warn("%s: select", testname);
  		return (-1);
  	}
  	*readable = FD_ISSET(fd, &readfds) ? 1 : 0;
  	*writable = FD_ISSET(fd, &writefds) ? 1 : 0;
  	*exception = FD_ISSET(fd, &exceptfds) ? 1 : 0;
  	return (0);
  }
  
  /*
   * Given an existing kqueue, set up read and write event filters for the
   * passed file descriptor.  Typically called once for the read endpoint, and
   * once for the write endpoint.
   */
  static int
  kqueue_setup(int kqueue_fd, int fd, const char *testname)
  {
  	struct kevent kevent_changelist[2];
  	struct kevent kevent_eventlist[KQUEUE_MAX_EVENT], *kp;
  	struct timespec timeout;
  	int i, ret;
  
  	timeout.tv_sec = 0;
  	timeout.tv_nsec = 0;
  
  	bzero(&kevent_changelist, sizeof(kevent_changelist));
  	EV_SET(&kevent_changelist[0], fd, EVFILT_READ, EV_ADD, 0, 0, 0);
  	EV_SET(&kevent_changelist[1], fd, EVFILT_WRITE, EV_ADD, 0, 0, 0);
  
  	bzero(&kevent_eventlist, sizeof(kevent_eventlist));
  	ret = kevent(kqueue_fd, kevent_changelist, 2, kevent_eventlist,
  	    KQUEUE_MAX_EVENT, &timeout);
  	if (ret < 0) {
  		warn("%s:%s: kevent initial register", testname, __func__);
  		return (-1);
  	}
  
  	/*
  	 * Verify that the events registered alright.
  	 */
  	for (i = 0; i < ret; i++) {
  		kp = &kevent_eventlist[i];
  		if (kp->flags != EV_ERROR)
  			continue;
  		errno = kp->data;
  		warn("%s:%s: kevent register index %d", testname, __func__,
  		    i);
  		return (-1);
  	}
  
  	return (0);
  }
  
  static int
  kqueue_status(int kqueue_fd, int fd, int *readable, int *writable,
      int *exception, const char *testname)
  {
  	struct kevent kevent_eventlist[KQUEUE_MAX_EVENT], *kp;
  	struct timespec timeout;
  	int i, ret;
  
  	timeout.tv_sec = 0;
  	timeout.tv_nsec = 0;
  
  	ret = kevent(kqueue_fd, NULL, 0, kevent_eventlist, KQUEUE_MAX_EVENT,
  	    &timeout);
  	if (ret < 0) {
  		warn("%s: %s: kevent", testname, __func__);
  		return (-1);
  	}
  
  	*readable = *writable = *exception = 0;
  	for (i = 0; i < ret; i++) {
  		kp = &kevent_eventlist[i];
  		if (kp->ident != (u_int)fd)
  			continue;
  		if (kp->filter == EVFILT_READ)
  			*readable = 1;
  		if (kp->filter == EVFILT_WRITE)
  			*writable = 1;
  	}
  
  	return (0);
  }
  
  static int
  fionread_status(int fd, int *readable, const char *testname)
  {
  	int i;
  
  	if (ioctl(fd, FIONREAD, &i) < 0) {
  		warn("%s: ioctl(FIONREAD)", testname);
  		return (-1);
  	}
  
  	if (i > 0)
  		*readable = 1;
  	else
  		*readable = 0;
  	return (0);
  }
  
  #define	READABLE	1
  #define	WRITABLE	1
  #define	EXCEPTION	1
  
  #define	NOT_READABLE	0
  #define	NOT_WRITABLE	0
  #define	NOT_EXCEPTION	0
  
  static int
  assert_status(int fd, int kqueue_fd, int assert_readable,
      int assert_writable, int assert_exception, const char *testname,
      const char *conditionname, const char *fdname)
  {
  	int readable, writable, exception;
  
  	if (poll_status(fd, &readable, &writable, &exception, testname) < 0)
  		return (-1);
  
  	if (readable != assert_readable || writable != assert_writable ||
  	    exception != assert_exception) {
  		warnx("%s: %s polls r:%d, w:%d, e:%d on %s", testname,
  		    fdname, readable, writable, exception, conditionname);
  		return (-1);
  	}
  
  	if (select_status(fd, &readable, &writable, &exception, testname) < 0)
  		return (-1);
  
  	if (readable != assert_readable || writable != assert_writable ||
  	    exception != assert_exception) {
  		warnx("%s: %s selects r:%d, w:%d, e:%d on %s", testname,
  		    fdname, readable, writable, exception, conditionname);
  		return (-1);
  	}
  
  	if (kqueue_status(kqueue_fd, fd, &readable, &writable, &exception,
  	    testname) < 0)
  		return (-1);
  
  	if (readable != assert_readable || writable != assert_writable ||
  	    exception != assert_exception) {
  		warnx("%s: %s kevent r:%d, w:%d, e:%d on %s", testname,
  		    fdname, readable, writable, exception, conditionname);
  		return (-1);
  	}
  
  	if (fionread_status(fd, &readable, __func__) < 0)
  		return (-1);
  
  	if (readable != assert_readable) {
  		warnx("%s: %s fionread r:%d on %s", testname, fdname,
  		    readable, conditionname);
  		return (-1);
  	}
  
  	return (0);
  }
  
  /*
   * test_events() uses poll(), select(), and kevent() to query the status of
   * fifo file descriptors and determine whether they match expected state
   * based on earlier semantic tests: specifically, whether or not poll/select/
   * kevent will correctly inform on readable/writable state following I/O.
   *
   * It would be nice to also test status changes as a result of closing of one
   * or another fifo endpoint.
   */
  static void
  test_events_outofbox(void)
  {
  	int kqueue_fd, reader_fd, writer_fd;
  
  	makefifo("testfifo", __func__);
  	if (openfifo("testfifo", &reader_fd, &writer_fd) < 0) {
  		warn("test_events_outofbox: openfifo: testfifo");
  		cleanfifo2("testfifo", -1, -1);
  		exit(-1);
  	}
  
  	kqueue_fd = kqueue();
  	if (kqueue_fd < 0) {
  		warn("%s: kqueue", __func__);
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  
  	if (kqueue_setup(kqueue_fd, reader_fd, __func__) < 0) {
  		cleanfifo3("testfifo", reader_fd, writer_fd, kqueue_fd);
  		exit(-1);
  	}
  
  	if (kqueue_setup(kqueue_fd, writer_fd, __func__) < 0) {
  		cleanfifo3("testfifo", reader_fd, writer_fd, kqueue_fd);
  		exit(-1);
  	}
  
  	/*
  	 * Make sure that fresh, out-of-the-box fifo file descriptors have
  	 * good initial states.  The reader_fd should have no active state,
  	 * since it will not be readable (no data in pipe), writable (it's
  	 * a read-only descriptor), and there's no reason for error yet.
  	 */
  	if (assert_status(reader_fd, kqueue_fd, NOT_READABLE, NOT_WRITABLE,
  	    NOT_EXCEPTION, __func__, "create", "reader_fd") < 0) {
  		cleanfifo3("testfifo", reader_fd, writer_fd, kqueue_fd);
  		exit(-1);
  	}
  
  	/*
  	 * Make sure that fresh, out-of-the-box fifo file descriptors have
  	 * good initial states.  The writer_fd should be ready to write.
  	 */
  	if (assert_status(writer_fd, kqueue_fd, NOT_READABLE, WRITABLE,
  	    NOT_EXCEPTION, __func__, "create", "writer_fd") < 0) {
  		cleanfifo3("testfifo", reader_fd, writer_fd, kqueue_fd);
  		exit(-1);
  	}
  
  	cleanfifo3("testfifo", reader_fd, writer_fd, kqueue_fd);
  }
  
  static void
  test_events_write_read_byte(void)
  {
  	int kqueue_fd, reader_fd, writer_fd;
  	ssize_t len;
  	u_char ch;
  
  	makefifo("testfifo", __func__);
  	if (openfifo("testfifo", &reader_fd, &writer_fd) < 0) {
  		warn("test_events_write_read_byte: openfifo: testfifo");
  		cleanfifo2("testfifo", -1, -1);
  		exit(-1);
  	}
  
  	kqueue_fd = kqueue();
  	if (kqueue_fd < 0) {
  		warn("%s: kqueue", __func__);
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  
  	if (kqueue_setup(kqueue_fd, reader_fd, __func__) < 0) {
  		cleanfifo3("testfifo", reader_fd, writer_fd, kqueue_fd);
  		exit(-1);
  	}
  
  	if (kqueue_setup(kqueue_fd, writer_fd, __func__) < 0) {
  		cleanfifo3("testfifo", reader_fd, writer_fd, kqueue_fd);
  		exit(-1);
  	}
  
  	/*
  	 * Write a byte to the fifo, and make sure that the read end becomes
  	 * readable, and that the write end remains writable (small write).
  	 */
  	ch = 0x00;
  	len = write(writer_fd, &ch, sizeof(ch));
  	if (len < 0) {
  		warn("%s: write", __func__);
  		cleanfifo3("testfifo", reader_fd, writer_fd, kqueue_fd);
  		exit(-1);
  	}
  
  	if (assert_status(reader_fd, kqueue_fd, READABLE, NOT_WRITABLE,
  	    NOT_EXCEPTION, __func__, "write", "reader_fd") < 0) {
  		cleanfifo3("testfifo", reader_fd, writer_fd, kqueue_fd);
  		exit(-1);
  	}
  
  	/*
  	 * the writer_fd should remain writable.
  	 */
  	if (assert_status(writer_fd, kqueue_fd, NOT_READABLE, WRITABLE,
  	    NOT_EXCEPTION, __func__, "write", "writer_fd") < 0) {
  		cleanfifo3("testfifo", reader_fd, writer_fd, kqueue_fd);
  		exit(-1);
  	}
  
  	/*
  	 * Read the byte from the reader_fd, and now confirm that the fifo
  	 * becomes unreadable.
  	 */
  	len = read(reader_fd, &ch, sizeof(ch));
  	if (len < 0) {
  		warn("%s: read", __func__);
  		cleanfifo3("testfifo", reader_fd, writer_fd, kqueue_fd);
  		exit(-1);
  	}
  
  	if (assert_status(reader_fd, kqueue_fd, NOT_READABLE, NOT_WRITABLE,
  	    NOT_EXCEPTION, __func__, "write+read", "reader_fd") < 0) {
  		cleanfifo3("testfifo", reader_fd, writer_fd, kqueue_fd);
  		exit(-1);
  	}
  
  	/*
  	 * The writer_fd should remain writable.
  	 */
  	if (assert_status(writer_fd, kqueue_fd, NOT_READABLE, WRITABLE,
  	    NOT_EXCEPTION, __func__, "write+read", "writer_fd") < 0) {
  		cleanfifo3("testfifo", reader_fd, writer_fd, kqueue_fd);
  		exit(-1);
  	}
  
  	cleanfifo3("testfifo", reader_fd, writer_fd, kqueue_fd);
  }
  
  /*
   * Write a 512k buffer to the fifo in non-blocking mode, and make sure that
   * the write end becomes un-writable as a result of a partial write that
   * fills the fifo buffer.
   */
  static void
  test_events_partial_write(void)
  {
  	int kqueue_fd, reader_fd, writer_fd;
  	u_char *buffer;
  	ssize_t len;
  
  	makefifo("testfifo", __func__);
  	if (openfifo("testfifo", &reader_fd, &writer_fd) < 0) {
  		warn("test_events_partial_write: openfifo: testfifo");
  		cleanfifo2("testfifo", -1, -1);
  		exit(-1);
  	}
  
  	kqueue_fd = kqueue();
  	if (kqueue_fd < 0) {
  		warn("%s: kqueue", __func__);
  		cleanfifo2("testfifo", reader_fd, writer_fd);
  		exit(-1);
  	}
  
  	if (kqueue_setup(kqueue_fd, reader_fd, __func__) < 0) {
  		cleanfifo3("testfifo", reader_fd, writer_fd, kqueue_fd);
  		exit(-1);
  	}
  
  	if (kqueue_setup(kqueue_fd, writer_fd, __func__) < 0) {
  		cleanfifo3("testfifo", reader_fd, writer_fd, kqueue_fd);
  		exit(-1);
  	}
  
  	if (set_nonblocking(writer_fd, "test_events") < 0) {
  		cleanfifo3("testfifo", reader_fd, writer_fd, kqueue_fd);
  		exit(-1);
  	}
  
  	buffer = malloc(512*1024);
  	if (buffer == NULL) {
  		warn("test_events_partial_write: malloc");
  		cleanfifo3("testfifo", reader_fd, writer_fd, kqueue_fd);
  		exit(-1);
  	}
  	bzero(buffer, 512*1024);
  
  	len = write(writer_fd, buffer, 512*1024);
  	if (len < 0) {
  		warn("test_events_partial_write: write");
  		free(buffer);
  		cleanfifo3("testfifo", reader_fd, writer_fd, kqueue_fd);
  		exit(-1);
  	}
  
  	free(buffer);
  
  	if (assert_status(writer_fd, kqueue_fd, NOT_READABLE, NOT_WRITABLE,
  	    NOT_EXCEPTION, __func__, "big write", "writer_fd") < 0) {
  		cleanfifo3("testfifo", reader_fd, writer_fd, kqueue_fd);
  		exit(-1);
  	}
  
  	if (drain_fd(reader_fd, "test_events") < 0) {
  		cleanfifo3("testfifo", reader_fd, writer_fd, kqueue_fd);
  		exit(-1);
  	}
  
  	/*
  	 * Test that the writer_fd has been restored to writable state after
  	 * draining.
  	 */
  	if (assert_status(writer_fd, kqueue_fd, NOT_READABLE, WRITABLE,
  	    NOT_EXCEPTION, __func__, "big write + drain", "writer_fd") < 0) {
  		cleanfifo3("testfifo", reader_fd, writer_fd, kqueue_fd);
  		exit(-1);
  	}
  
  	cleanfifo3("testfifo", reader_fd, writer_fd, kqueue_fd);
  }
  
  /*
   * We don't comprehensively test O_RDWR file descriptors, but do run a couple
   * of event tests to make sure that the fifo implementation doesn't mixed up
   * status checks.  In particular, at least one past FreeBSD bug exists in
   * which the FIONREAD test was performed on the wrong socket implementing the
   * fifo, resulting in the fifo never returning readable.
   */
  static void
  test_events_rdwr(void)
  {
  	int fd, kqueue_fd;
  	ssize_t len;
  	char ch;
  
  	makefifo("testfifo", __func__);
  	if (openfifo_rw("testfifo", &fd) < 0) {
  		warn("%s: openfifo_rw: testfifo", __func__);
  		cleanfifo2("testfifo", -1, -1);
  		exit(-1);
  	}
  
  	kqueue_fd = kqueue();
  	if (kqueue_fd < 0) {
  		warn("%s: kqueue", __func__);
  		cleanfifo2("testifo", fd, -1);
  		exit(-1);
  	}
  
  	if (kqueue_setup(kqueue_fd, fd, __func__) < 0) {
  		cleanfifo2("testfifo", fd, kqueue_fd);
  		exit(-1);
  	}
  
  	/*
  	 * On first creation, the O_RDWR descriptor should be writable but
  	 * not readable.
  	 */
  	if (assert_status(fd, kqueue_fd, NOT_READABLE, WRITABLE,
  	    NOT_EXCEPTION, __func__, "create", "fd") < 0) {
  		cleanfifo2("testfifo", fd, kqueue_fd);
  		exit(-1);
  	}
  
  	/*
  	 * Write a byte, which should cause the file descriptor to become
  	 * readable and writable.
  	 */
  	ch = 0x00;
  	len = write(fd, &ch, sizeof(ch));
  	if (len < 0) {
  		warn("%s: write", __func__);
  		cleanfifo2("testfifo", fd, kqueue_fd);
  		exit(-1);
  	}
  
  	if (assert_status(fd, kqueue_fd, READABLE, WRITABLE, NOT_EXCEPTION,
  	    __func__, "write", "fd") < 0) {
  		cleanfifo2("testfifo", fd, kqueue_fd);
  		exit(-1);
  	}
  
  	/*
  	 * Read a byte, which should cause the file descriptor to return to
  	 * simply being writable.
  	 */
  	len = read(fd, &ch, sizeof(ch));
  	if (len < 0) {
  		warn("%s: read", __func__);
  		cleanfifo2("testfifo", fd, kqueue_fd);
  		exit(-1);
  	}
  
  	if (assert_status(fd, kqueue_fd, NOT_READABLE, WRITABLE,
  	    NOT_EXCEPTION, __func__, "write+read", "fd") < 0) {
  		cleanfifo2("testfifo", fd, kqueue_fd);
  		exit(-1);
  	}
  
  	cleanfifo2("testfifo", fd, kqueue_fd);
  }
  
  int
  main(void)
  {
  
  	strcpy(temp_dir, "fifo_io.XXXXXXXXXXX");
  	if (mkdtemp(temp_dir) == NULL)
  		err(-1, "mkdtemp");
  	atexit(atexit_temp_dir);
  
  	if (chdir(temp_dir) < 0)
  		err(-1, "chdir %s", temp_dir);
  
  	test_simpleio();
  	test_blocking_read_empty();
  	test_blocking_one_byte();
  	test_nonblocking_one_byte();
  	test_blocking_partial_write();
  	test_nonblocking_partial_write();
  	test_coalesce_big_read();
  	test_coalesce_big_write();
  	test_events_outofbox();
  	test_events_write_read_byte();
  	test_events_partial_write();
  	test_events_rdwr();
  
  	return (0);
  }
  