src/tests/write-closed.c

   1 /*
   2  * Copyright (c) 2000 Kungliga Tekniska Högskolan
   3  * (Royal Institute of Technology, Stockholm, Sweden).
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  *
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  *
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  *
  17  * 3. Neither the name of the Institute nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 #ifdef HAVE_CONFIG_H
  35 #include <config.h>
  36 #endif
  37
  38 #include <stdio.h>
  39 #include <stdlib.h>
  40 #include <string.h>
  41 #include <errno.h>
  42
  43 #include <sys/types.h>
  44 #include <sys/stat.h>
  45 #include <sys/mman.h>
  46 #include <fcntl.h>
  47 #include <unistd.h>
  48 #include <dirent.h>
  49
  50
  51 #include <err.h>
  52
  53 #ifndef MAP_FAILED
  54 #define MAP_FAILED ((void *)-1)
  55 #endif
  56
  57 static void
  58 doit(const char *filename)
  59 {
  60     int fd;
  61     int ret;
  62     void *buf;
  63
  64     fd = open(filename, O_RDWR | O_CREAT | O_TRUNC, 0600);
  65     if (fd < 0)
  66         err(1, "open %s", filename);
  67     ret = ftruncate(fd, 1);
  68     if (ret < 0)
  69         err(1, "ftruncate %s", filename);
  70     buf = mmap(NULL, 1, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
  71     if (buf == (void *)MAP_FAILED)
  72         err(1, "mmap");
  73     if (fchmod(fd, 0) < 0)
  74         err(1, "fchmod %s, 0", filename);
  75     ret = close(fd);
  76     if (ret < 0)
  77         err(1, "close %s", filename);
  78     *((char *)buf) = 0x17;
  79     ret = munmap(buf, 1);
  80     if (ret < 0)
  81         err(1, "munmap");
  82 }
  83
  84 int
  85 main(int argc, char **argv)
  86 {
  87     const char *file = "foo";
  88
  89     if (argc != 1 && argc != 2)
  90         errx(1, "usage: %s [file]", argv[0]);
  91     if (argc == 2)
  92         file = argv[1];
  93     doit(file);
  94     return 0;
  95 }