1
0
mirror of https://git.FreeBSD.org/src.git synced 2024-12-20 11:11:24 +00:00
freebsd/tests/sys/fifo/fifo_open.c
Enji Cooper 3cedbec3ee Integrate tools/regression/fifo into the FreeBSD test suite as tests/sys/fifo
and tools/regression/file into the FreeBSD test suite as tests/sys/file

MFC after: 1 week
2015-04-27 08:15:17 +00:00

477 lines
11 KiB
C

/*-
* 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/stat.h>
#include <sys/wait.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <limits.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
/*
* Regression test to exercise various POSIX-defined parts of fifo behavior
* described for open(2):
*
* O_NONBLOCK
* When opening a FIFO with O_RDONLY or O_WRONLY set:
*
* - If O_NONBLOCK is set, an open() for reading-only shall return without
* delay. An open() for writing-only shall return an error if no process
* currently has the file open for reading.
*
* - If O_NONBLOCK is clear, an open() for reading-only shall block the
* calling thread until a thread opens the file for writing. An open()
* for writing-only shall block the calling thread until a thread opens
* the file for reading.
*
* When opening a block special or character special file that supports
* non-blocking opens:
*
* - If O_NONBLOCK is set, the open() function shall return without blocking
* for the device to be ready or available. Subsequent behavior of the
* device is device-specific.
*
* - If O_NONBLOCK is clear, the open() function shall block the calling
* thread until the device is ready or available before returning.
*
* Special errors:
*
* [ENXIO]
* O_NONBLOCK is set, the named file is a FIFO, O_WRONLY is set, and no
* process has the file open for reading.
*/
/*
* In order to test blocking/non-blocking behavior, test processes must
* potentially block themselves until released. As bugs in blocking result
* in processes that won't un-block, we must sacrifice a process to the task,
* watching and potentially killing it after a time-out. The main test
* process is never used to open or act directly on a fifo (other than to
* create or unlink it) in order to avoid the main test process being
* blocked.
*/
/*
* 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);
}
/*
* Run a function in a particular test process.
*/
static int
run_in_process(int (*func)(void), pid_t *pidp, const char *errstr)
{
pid_t pid;
pid = fork();
if (pid < 0) {
warn("%s: run_in_process: fork", errstr);
return (-1);
}
if (pid == 0)
exit(func());
if (pidp != NULL)
*pidp = pid;
return (0);
}
/*
* Wait for a process on a timeout, and if the timeout expires, kill the
* process. Test each second rather than waiting the full timeout at once to
* minimize the amount of time spent hanging around unnecessarily.
*/
static int
wait_and_timeout(pid_t pid, int timeout, int *status, const char *errstr)
{
pid_t wpid;
int i;
/*
* Count up to the timeout, but do a non-hanging waitpid() after each
* second so we can avoid waiting a lot of extra time.
*/
for (i = 0; i < timeout; i++) {
wpid = waitpid(pid, status, WNOHANG);
if (wpid < 0) {
warn("%s: wait_and_timeout: waitpid %d", errstr, pid);
return (-1);
}
if (wpid == pid)
return (0);
sleep(1);
}
wpid = waitpid(pid, status, WNOHANG);
if (wpid < 0) {
warn("%s: wait_and_timeout: waitpid %d", errstr, pid);
return (-1);
}
if (wpid == pid)
return (0);
if (kill(pid, SIGTERM) < 0) {
warn("%s: wait_and_timeout: kill %d", errstr, pid);
return (-1);
}
wpid = waitpid(pid, status, 0);
if (wpid < 0) {
warn("%s: wait_and_timeout: waitpid %d", errstr, pid);
return (-1);
}
if (wpid != pid) {
warn("%s: waitpid: returned %d not %d", errstr, wpid, pid);
return (-1);
}
warnx("%s: process blocked", errstr);
return (-1);
}
static int
non_blocking_open_reader(void)
{
int fd;
fd = open("testfifo", O_RDONLY | O_NONBLOCK);
if (fd < 0)
return (errno);
close(fd);
return (0);
}
static int
non_blocking_open_writer(void)
{
int fd;
fd = open("testfifo", O_WRONLY | O_NONBLOCK);
if (fd < 0)
return (errno);
close(fd);
return (0);
}
static int
blocking_open_reader(void)
{
int fd;
fd = open("testfifo", O_RDONLY);
if (fd < 0)
return (errno);
close(fd);
return (0);
}
static int
blocking_open_writer(void)
{
int fd;
fd = open("testfifo", O_WRONLY);
if (fd < 0)
return (errno);
close(fd);
return (0);
}
static void
test_blocking_reader(void)
{
pid_t reader_pid, writer_pid, wpid;
int error, status;
if (mkfifo("testfifo", 0600) < 0)
err(-1, "test_blocking_reader: mkfifo: testfifo");
/*
* Block a process in opening the fifo.
*/
if (run_in_process(blocking_open_reader, &reader_pid,
"test_blocking_reader: blocking_open_reader") < 0) {
(void)unlink("testfifo");
exit(-1);
}
/*
* Test that it blocked.
*/
sleep(5);
wpid = waitpid(reader_pid, &status, WNOHANG);
if (wpid < 0) {
error = errno;
(void)unlink("testfifo");
errno = error;
err(-1, "test_blocking_reader: waitpid %d", reader_pid);
}
if (wpid != 0 && wpid != reader_pid) {
(void)unlink("testfifo");
errx(-1, "test_blocking_reader: waitpid %d returned %d",
reader_pid, wpid);
}
if (wpid == reader_pid) {
(void)unlink("testfifo");
errx(-1, "test_blocking_reader: blocking child didn't "
"block");
}
/*
* Unblock the blocking reader.
*/
if (run_in_process(blocking_open_writer, &writer_pid,
"test_blocking_reader: blocking_open_writer") < 0) {
(void)unlink("testfifo");
(void)kill(reader_pid, SIGTERM);
(void)waitpid(reader_pid, &status, 0);
exit(-1);
}
/*
* Make sure both processes exited quickly (<1 second) to make sure
* they didn't block, and GC.
*/
if (wait_and_timeout(reader_pid, 1, &status,
"test_blocking_reader: blocking_open_reader") < 0) {
(void)unlink("testinfo");
(void)kill(reader_pid, SIGTERM);
(void)kill(writer_pid, SIGTERM);
exit(-1);
}
if (wait_and_timeout(writer_pid, 1, &status,
"test_blocking_reader: blocking_open_writer") < 0) {
(void)unlink("testinfo");
(void)kill(writer_pid, SIGTERM);
exit(-1);
}
if (unlink("testfifo") < 0)
err(-1, "test_blocking_reader: unlink: testfifo");
}
static void
test_blocking_writer(void)
{
pid_t reader_pid, writer_pid, wpid;
int error, status;
if (mkfifo("testfifo", 0600) < 0)
err(-1, "test_blocking_writer: mkfifo: testfifo");
/*
* Block a process in opening the fifo.
*/
if (run_in_process(blocking_open_writer, &writer_pid,
"test_blocking_writer: blocking_open_writer") < 0) {
(void)unlink("testfifo");
exit(-1);
}
/*
* Test that it blocked.
*/
sleep(5);
wpid = waitpid(writer_pid, &status, WNOHANG);
if (wpid < 0) {
error = errno;
(void)unlink("testfifo");
errno = error;
err(-1, "test_blocking_writer: waitpid %d", writer_pid);
}
if (wpid != 0 && wpid != writer_pid) {
(void)unlink("testfifo");
errx(-1, "test_blocking_writer: waitpid %d returned %d",
writer_pid, wpid);
}
if (wpid == writer_pid) {
(void)unlink("testfifo");
errx(-1, "test_blocking_writer: blocking child didn't "
"block");
}
/*
* Unblock the blocking writer.
*/
if (run_in_process(blocking_open_reader, &reader_pid,
"test_blocking_writer: blocking_open_reader") < 0) {
(void)unlink("testfifo");
(void)kill(writer_pid, SIGTERM);
(void)waitpid(writer_pid, &status, 0);
exit(-1);
}
/*
* Make sure both processes exited quickly (<1 second) to make sure
* they didn't block, and GC.
*/
if (wait_and_timeout(writer_pid, 1, &status,
"test_blocking_writer: blocking_open_writer") < 0) {
(void)unlink("testinfo");
(void)kill(writer_pid, SIGTERM);
(void)kill(reader_pid, SIGTERM);
(void)waitpid(writer_pid, &status, 0);
(void)waitpid(reader_pid, &status, 0);
exit(-1);
}
if (wait_and_timeout(reader_pid, 1, &status,
"test_blocking_writer: blocking_open_reader") < 0) {
(void)unlink("testinfo");
(void)kill(reader_pid, SIGTERM);
(void)waitpid(reader_pid, &status, 0);
exit(-1);
}
if (unlink("testfifo") < 0)
err(-1, "test_blocking_writer: unlink: testfifo");
}
static void
test_non_blocking_reader(void)
{
int status;
pid_t pid;
if (mkfifo("testfifo", 0600) < 0)
err(-1, "test_non_blocking_reader: mkfifo: testfifo");
if (run_in_process(non_blocking_open_reader, &pid,
"test_non_blocking_reader: non_blocking_open_reader") < 0) {
(void)unlink("testfifo");
exit(-1);
}
status = -1;
if (wait_and_timeout(pid, 5, &status,
"test_non_blocking_reader: non_blocking_open_reader") < 0) {
(void)unlink("testfifo");
exit(-1);
}
if (WEXITSTATUS(status) != 0) {
(void)unlink("testfifo");
errno = WEXITSTATUS(status);
err(-1, "test_non_blocking_reader: "
"non_blocking_open_reader: open: testfifo");
}
if (unlink("testfifo") < 0)
err(-1, "test_non_blocking_reader: unlink: testfifo");
}
static void
test_non_blocking_writer(void)
{
int status;
pid_t pid;
if (mkfifo("testfifo", 0600) < 0)
err(-1, "test_non_blocking_writer: mkfifo: testfifo");
if (run_in_process(non_blocking_open_writer, &pid,
"test_non_blocking_writer: non_blocking_open_writer") < 0) {
(void)unlink("testfifo");
exit(-1);
}
status = -1;
if (wait_and_timeout(pid, 5, &status,
"test_non_blocking_writer: non_blocking_open_writer") < 0) {
(void)unlink("testfifo");
exit(-1);
}
if (WEXITSTATUS(status) != ENXIO) {
(void)unlink("testfifo");
errno = WEXITSTATUS(status);
if (errno == 0)
errx(-1, "test_non_blocking_writer: "
"non_blocking_open_writer: open succeeded");
err(-1, "test_non_blocking_writer: "
"non_blocking_open_writer: open: testfifo");
}
if (unlink("testfifo") < 0)
err(-1, "test_non_blocking_writer: unlink: testfifo");
}
int
main(void)
{
if (geteuid() != 0)
errx(-1, "must be run as root");
strcpy(temp_dir, "fifo_open.XXXXXXXXXXX");
if (mkdtemp(temp_dir) == NULL)
err(-1, "mkdtemp");
if (chdir(temp_dir) < 0)
err(-1, "chdir: %s", temp_dir);
atexit(atexit_temp_dir);
test_non_blocking_reader();
test_non_blocking_writer();
test_blocking_reader();
test_blocking_writer();
return (0);
}