1  /* Copyright (C) 1990-2023 Free Software Foundation, Inc.
       2     This file is part of the GNU C Library.
       3  
       4     The GNU C Library is free software; you can redistribute it and/or
       5     modify it under the terms of the GNU Lesser General Public
       6     License as published by the Free Software Foundation; either
       7     version 2.1 of the License, or (at your option) any later version.
       8  
       9     The GNU C Library is distributed in the hope that it will be useful,
      10     but WITHOUT ANY WARRANTY; without even the implied warranty of
      11     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
      12     Lesser General Public License for more details.
      13  
      14     You should have received a copy of the GNU Lesser General Public
      15     License along with the GNU C Library; if not, see
      16     <https://www.gnu.org/licenses/>.  */
      17  
      18  #include <stdlib.h>
      19  #include <stdio.h>
      20  #include <string.h>
      21  #include <support/support.h>
      22  
      23  static int
      24  do_test (void)
      25  {
      26    char *mem, *memp;
      27    char *rand_mem;
      28    char *lo_around, *hi_around;
      29    int size, max_size;
      30    int src_off, dst_off;
      31    int i;
      32    int space_around = 10;
      33  
      34    max_size = 256;
      35  
      36    mem = xmalloc (max_size + 2 * max_size + 2 * space_around);
      37    rand_mem = xmalloc (max_size);
      38    lo_around = xmalloc (space_around);
      39    hi_around = xmalloc (space_around);
      40    memp = mem + space_around;
      41  
      42    /* Fill RAND_MEM with random bytes, each non-zero.  */
      43    for (i = 0; i < max_size; i++)
      44      {
      45        int x;
      46        do
      47  	x = random ();
      48        while (x == 0);
      49        rand_mem[i] = x;
      50      }
      51  
      52    for (size = 0; size < max_size; size++)
      53      {
      54        printf("phase %d\n", size);
      55        for (src_off = 0; src_off <= 16; src_off++)
      56  	{
      57  	  for (dst_off = 0; dst_off <= 16; dst_off++)
      58  	    {
      59  	      /* Put zero around the intended destination, to check
      60  		 that it's not clobbered.  */
      61  	      for (i = 1; i < space_around; i++)
      62  		{
      63  		  memp[dst_off - i] = 0;
      64  		  memp[dst_off + size - 1 + i] = 0;
      65  		}
      66  
      67  	      /* Fill the source area with known contents.  */
      68  	      for (i = 0; i < size; i++)
      69  		memp[src_off + i] = rand_mem[i];
      70  
      71  	      /* Remember the contents around the destination area.
      72  		 (It might not be what we wrote some lines above, since
      73  		 the src area and the dst area overlap.)  */
      74  	      for (i = 1; i < space_around; i++)
      75  		{
      76  		  lo_around[i] = memp[dst_off - i];
      77  		  hi_around[i] = memp[dst_off + size - 1 + i];
      78  		}
      79  
      80  	      memmove (memp + dst_off, memp + src_off, size);
      81  
      82  	      /* Check that the destination area has the same
      83  		 contents we wrote to the source area.  */
      84  	      for (i = 0; i < size; i++)
      85  		{
      86  		  if (memp[dst_off + i] != rand_mem[i])
      87  		    abort ();
      88  		}
      89  
      90  	      /* Check that the area around the destination is not
      91  		 clobbered.  */
      92  	      for (i = 1; i < space_around; i++)
      93  		{
      94  		  if (memp[dst_off - i] != lo_around[i])
      95  		    abort ();
      96  		  if (memp[dst_off + size - 1 + i] != hi_around[i])
      97  		    abort ();
      98  		}
      99  	    }
     100  	}
     101      }
     102  
     103    puts ("Test succeeded.");
     104  
     105    return 0;
     106  }
     107  
     108  #include <support/test-driver.c>