src/tests/mmap-and-read.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
  49 #ifndef MAP_FAILED
  50 #define MAP_FAILED ((void *)-1)
  51 #endif
  52
  53 static char *
  54 generate_random_file(const char *filename, unsigned npages, unsigned pagesize,
  55                      int writep)
  56 {
  57     int fd;
  58     char *buf, *fbuf;
  59     int i;
  60     int prot;
  61     int flags;
  62     size_t sz = npages * pagesize;
  63
  64     buf = malloc(sz);
  65     if (buf == NULL)
  66         err(1, "malloc %u", (unsigned)sz);
  67
  68     for (i = 0; i < npages; ++i)
  69         memset(buf + pagesize * i, '0' + i, pagesize);
  70
  71     fd = open(filename, O_RDWR | O_CREAT | O_TRUNC, 0666);
  72     if (fd < 0)
  73         err(1, "open %s", filename);
  74
  75     if (ftruncate(fd, sz) < 0)
  76         err(1, "ftruncate");
  77
  78     prot = PROT_READ | PROT_WRITE;
  79     flags = MAP_SHARED;
  80
  81     fbuf = mmap(0, sz, prot, flags, fd, 0);
  82     if (fbuf == (void *)MAP_FAILED)
  83         err(1, "mmap");
  84
  85     if (writep) {
  86         if (write(fd, "hej\n", 4) != 4)
  87             err(1, "write");
  88     }
  89
  90     memcpy(fbuf, buf, sz);
  91
  92 #if 0
  93     if (msync(fbuf, sz, MS_SYNC))
  94         err(1, "msync");
  95 #endif
  96
  97     if (munmap(fbuf, sz) != 0)
  98         err(1, "munmap");
  99
 100     if (close(fd))
 101         err(1, "close");
 102     return buf;
 103 }
 104
 105 static char *
 106 read_file(int fd, size_t sz)
 107 {
 108     char *buf;
 109     ssize_t ret;
 110
 111     buf = malloc(sz);
 112     if (buf == NULL)
 113         err(1, "malloc %u", (unsigned)sz);
 114     ret = read(fd, buf, sz);
 115     if (ret < 0)
 116         err(1, "read");
 117     if (ret != sz)
 118         errx(1, "short read %d < %u", (int)ret, (unsigned)sz);
 119     return buf;
 120 }
 121
 122 static int
 123 test(const char *file, int writep)
 124 {
 125     const size_t sz = 4 * getpagesize();
 126     char *buf;
 127     char *malloc_buf;
 128     int fd;
 129     int ret;
 130
 131     buf = generate_random_file(file, 4, getpagesize(), writep);
 132
 133     fd = open(file, O_RDONLY, 0);
 134     if (fd < 0)
 135         err(1, "open %s", file);
 136
 137     malloc_buf = read_file(fd, sz);
 138     close(fd);
 139     ret = memcmp(buf, malloc_buf, sz);
 140     free(buf);
 141
 142     return ret;
 143 }
 144
 145
 146 int
 147 main(int argc, char **argv)
 148 {
 149
 150
 151     srand(time(NULL));
 152
 153     if (test("foo", 1) != 0)
 154         errx(1, "test(1)");
 155     if (test("bar", 0) != 0)
 156         errx(1, "test(2)");
 157
 158     return 0;
 159 }