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Diffstat (limited to 'tests/sys/fifo/fifo_open.c')
| -rw-r--r-- | tests/sys/fifo/fifo_open.c | 476 |
1 files changed, 476 insertions, 0 deletions
diff --git a/tests/sys/fifo/fifo_open.c b/tests/sys/fifo/fifo_open.c new file mode 100644 index 0000000..892f481 --- /dev/null +++ b/tests/sys/fifo/fifo_open.c @@ -0,0 +1,476 @@ +/*- + * 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); +} |
