1  /* Copyright (C) 2002  Free Software Foundation.
       2  
       3     Test memcpy with various combinations of pointer alignments and lengths to
       4     make sure any optimizations in the library are correct.
       5  
       6     Written by Michael Meissner, March 9, 2002.  */
       7  
       8  #include <string.h>
       9  
      10  #ifndef MAX_OFFSET
      11  #define MAX_OFFSET (sizeof (long long))
      12  #endif
      13  
      14  #ifndef MAX_COPY
      15  #define MAX_COPY (10 * sizeof (long long))
      16  #endif
      17  
      18  #ifndef MAX_EXTRA
      19  #define MAX_EXTRA (sizeof (long long))
      20  #endif
      21  
      22  #define MAX_LENGTH (MAX_OFFSET + MAX_COPY + MAX_EXTRA)
      23  
      24  
      25  /* Use a sequence length that is not divisible by two, to make it more
      26     likely to detect when words are mixed up.  */
      27  #define SEQUENCE_LENGTH 31
      28  
      29  static union {
      30    char buf[MAX_LENGTH];
      31    long long align_int;
      32    long double align_fp;
      33  } u1, u2;
      34  
      35  main ()
      36  {
      37    int off1, off2, len, i;
      38    char *p, *q, c;
      39  
      40    for (off1 = 0; off1 < MAX_OFFSET; off1++)
      41      for (off2 = 0; off2 < MAX_OFFSET; off2++)
      42        for (len = 1; len < MAX_COPY; len++)
      43  	{
      44  	  for (i = 0, c = 'A'; i < MAX_LENGTH; i++, c++)
      45  	    {
      46  	      u1.buf[i] = 'a';
      47  	      if (c >= 'A' + SEQUENCE_LENGTH)
      48  		c = 'A';
      49  	      u2.buf[i] = c;
      50  	    }
      51  
      52  	  p = memcpy (u1.buf + off1, u2.buf + off2, len);
      53  	  if (p != u1.buf + off1)
      54  	    abort ();
      55  
      56  	  q = u1.buf;
      57  	  for (i = 0; i < off1; i++, q++)
      58  	    if (*q != 'a')
      59  	      abort ();
      60  
      61  	  for (i = 0, c = 'A' + off2; i < len; i++, q++, c++)
      62  	    {
      63  	      if (c >= 'A' + SEQUENCE_LENGTH)
      64  		c = 'A';
      65  	      if (*q != c)
      66  		abort ();
      67  	    }
      68  
      69  	  for (i = 0; i < MAX_EXTRA; i++, q++)
      70  	    if (*q != 'a')
      71  	      abort ();
      72  	}
      73  
      74    exit (0);
      75  }