string/testcopy.c

   1 /* Copyright (C) 1990, 1991, 1992, 1997 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Torbjorn Granlund (tege@sics.se).
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, write to the Free
  17    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  18    02111-1307 USA.  */
  19
  20 #include <stdlib.h>
  21 #include <stdio.h>
  22 #include <string.h>
  23 #include <malloc.h>
  24
  25 int
  26 main (void)
  27 {
  28   char *mem, *memp;
  29   char *rand_mem;
  30   char *lo_around, *hi_around;
  31   int size, max_size;
  32   int src_off, dst_off;
  33   int i;
  34   int space_around = 10;
  35
  36   max_size = 256;
  37
  38   mem = malloc (max_size + 2 * max_size + 2 * space_around);
  39   rand_mem = malloc (max_size);
  40   lo_around = malloc (space_around);
  41   hi_around = malloc (space_around);
  42   memp = mem + space_around;
  43
  44   /* Fill RAND_MEM with random bytes, each non-zero.  */
  45   for (i = 0; i < max_size; i++)
  46     {
  47       int x;
  48       do
  49         x = random ();
  50       while (x == 0);
  51       rand_mem[i] = x;
  52     }
  53
  54   for (size = 0; size < max_size; size++)
  55     {
  56       printf("phase %d\n", size);
  57       for (src_off = 0; src_off <= 16; src_off++)
  58         {
  59           for (dst_off = 0; dst_off <= 16; dst_off++)
  60             {
  61               /* Put zero around the intended destination, to check
  62                  that it's not clobbered.  */
  63               for (i = 1; i < space_around; i++)
  64                 {
  65                   memp[dst_off - i] = 0;
  66                   memp[dst_off + size - 1 + i] = 0;
  67                 }
  68
  69               /* Fill the source area with known contents.  */
  70               for (i = 0; i < size; i++)
  71                 memp[src_off + i] = rand_mem[i];
  72
  73               /* Remember the contents around the destination area.
  74                  (It might not be what we wrote some lines above, since
  75                  the src area and the dst area overlap.)  */
  76               for (i = 1; i < space_around; i++)
  77                 {
  78                   lo_around[i] = memp[dst_off - i];
  79                   hi_around[i] = memp[dst_off + size - 1 + i];
  80                 }
  81
  82               memmove (memp + dst_off, memp + src_off, size);
  83
  84               /* Check that the destination area has the same
  85                  contents we wrote to the source area.  */
  86               for (i = 0; i < size; i++)
  87                 {
  88                   if (memp[dst_off + i] != rand_mem[i])
  89                     abort ();
  90                 }
  91
  92               /* Check that the area around the destination is not
  93                  clobbered.  */
  94               for (i = 1; i < space_around; i++)
  95                 {
  96                   if (memp[dst_off - i] != lo_around[i])
  97                     abort ();
  98                   if (memp[dst_off + size - 1 + i] != hi_around[i])
  99                     abort ();
 100                 }
 101             }
 102         }
 103     }
 104
 105   puts ("Test succeeded.");
 106
 107   return 0;
 108 }