tests/read-write.c

   1 /*
   2  * Copyright (c) 1995 - 2001 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 <sys/types.h>
  41 #include <fcntl.h>
  42 #include <time.h>
  43 #include <unistd.h>
  44 #include <string.h>
  45 #include <sys/mman.h>
  46 #include <sys/stat.h>
  47 #include <err.h>
  48 #include <roken.h>
  49
  50 #ifdef RCSID
  51 RCSID("$Id$");
  52 #endif
  53
  54 static char *
  55 write_random_file (int fd, size_t sz)
  56 {
  57     char *buf;
  58     int i;
  59
  60     buf = malloc (sz);
  61     if (buf == NULL)
  62         err (1, "malloc %u", (unsigned)sz);
  63
  64     for (i = 0; i < sz; ++i)
  65         buf[i] = rand();
  66
  67     if (write (fd, buf, sz) != sz)
  68         err (1, "write");
  69
  70     return buf;
  71 }
  72
  73 static void
  74 write_null_file (int fd, size_t sz)
  75 {
  76     char *buf;
  77     int i;
  78
  79     buf = malloc (sz);
  80     if (buf == NULL)
  81         err (1, "malloc %u", (unsigned)sz);
  82
  83     for (i = 0; i < sz; ++i)
  84         buf[i] = 0;
  85
  86     if (write (fd, buf, sz) != sz)
  87         err (1, "write");
  88
  89     free (buf);
  90 }
  91
  92 static char *
  93 read_file (int fd, size_t sz)
  94 {
  95     char *buf;
  96     ssize_t ret;
  97
  98     buf = malloc (sz);
  99     if (buf == NULL)
 100         err (1, "malloc %u", (unsigned)sz);
 101     ret = read(fd, buf, sz);
 102     if(ret < 0)
 103         err (1, "read");
 104     else if(ret == 0)
 105         errx(1, "EOF on read");
 106     return buf;
 107 }
 108
 109 #ifndef MAP_FAILED
 110 #define MAP_FAILED ((void *)-1)
 111 #endif
 112
 113 int
 114 main (int argc, char **argv)
 115 {
 116     const char *file = "foo";
 117     const size_t sz  = 16384;
 118     char *random_buf;
 119     char *read_buf1;
 120     char *read_buf2;
 121     int fd;
 122
 123     setprogname (argv[0]);
 124
 125     srand (time(NULL));
 126
 127     fd = open (file, O_RDWR | O_CREAT, 0);
 128     if (fd < 0)
 129         err (1, "open %s", file);
 130
 131     if (lseek(fd, 0, SEEK_SET) < 0)
 132         err (1, "lseek");
 133     write_null_file(fd, sz);
 134     if (lseek(fd, 0, SEEK_SET) < 0)
 135         err (1, "lseek");
 136     read_buf1 = read_file (fd, sz);
 137     if (lseek(fd, 0, SEEK_SET) < 0)
 138         err (1, "lseek");
 139     random_buf = write_random_file(fd, sz);
 140     if (lseek(fd, 0, SEEK_SET) < 0)
 141         err (1, "lseek");
 142     read_buf2 = read_file (fd, sz);
 143
 144     close (fd);
 145     unlink (file);
 146     if (memcmp (random_buf, read_buf2, sz) != 0)
 147         return 1;
 148     return 0;
 149 }