FreeBSD/Linux Kernel Cross Reference
sys/contrib/openzfs/tests/zfs-tests/cmd/dosmode_readonly_write.c

     /*
      * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
      *
      * Copyright (c) 2021 iXsystems, Inc.
      *
      * 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.
     *
     * Test for correct behavior of DOS mode READONLY flag on a file.
     * We should be able to open a file RW, set READONLY, and still write to the fd.
     */
    
    #include <sys/stat.h>
    #include <err.h>
    #include <errno.h>
    #include <fcntl.h>
    #include <stdio.h>
    #include <string.h>
    #include <unistd.h>
    
    #ifdef __linux__
    #include <stdint.h>
    #include <sys/fs/zfs.h>
    #endif
    
    int
    main(int argc, const char *argv[])
    {
            const char *buf = "We should be allowed to write this to the fd.\n";
            const char *path;
            int fd;
    
            if (argc != 2) {
                    fprintf(stderr, "usage: %s PATH\n", argv[0]);
                    return (EXIT_FAILURE);
            }
            path = argv[1];
            fd = open(path, O_CREAT|O_RDWR, 0777);
            if (fd == -1)
                    err(EXIT_FAILURE, "%s: open failed", path);
    #ifdef __linux__
            uint64_t dosflags = ZFS_READONLY;
            if (ioctl(fd, ZFS_IOC_SETDOSFLAGS, &dosflags) == -1)
                    err(EXIT_FAILURE, "%s: ZFS_IOC_SETDOSFLAGS failed", path);
    #else
            if (chflags(path, UF_READONLY) == -1)
                    err(EXIT_FAILURE, "%s: chflags failed", path);
    #endif
            if (write(fd, buf, strlen(buf)) == -1)
                    err(EXIT_FAILURE, "%s: write failed", path);
            if (close(fd) == -1)
                    err(EXIT_FAILURE, "%s: close failed", path);
            return (EXIT_SUCCESS);
    }

Cache object: b6f55db1ef844db21bb2ac15f96a2124