gnu/dist/gcc4/gcc/testsuite/gcc.c-torture/execute/strncmp-1.c

   1 /* Copyright (C) 2002  Free Software Foundation.
   2
   3    Test strncmp 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 #include <stddef.h>
  10
  11 #ifndef MAX_OFFSET
  12 #define MAX_OFFSET (sizeof (long long))
  13 #endif
  14
  15 #ifndef MAX_TEST
  16 #define MAX_TEST (8 * sizeof (long long))
  17 #endif
  18
  19 #ifndef MAX_EXTRA
  20 #define MAX_EXTRA (sizeof (long long))
  21 #endif
  22
  23 #define MAX_LENGTH (MAX_OFFSET + MAX_TEST + MAX_EXTRA)
  24
  25 static union {
  26   unsigned char buf[MAX_LENGTH];
  27   long long align_int;
  28   long double align_fp;
  29 } u1, u2;
  30
  31 void
  32 test (const unsigned char *s1, const unsigned char *s2, size_t len, int expected)
  33 {
  34   int value = strncmp ((char *) s1, (char *) s2, len);
  35
  36   if (expected < 0 && value >= 0)
  37     abort ();
  38   else if (expected == 0 && value != 0)
  39     abort ();
  40   else if (expected > 0 && value <= 0)
  41     abort ();
  42 }
  43
  44 main ()
  45 {
  46   size_t off1, off2, len, i;
  47   unsigned char *buf1, *buf2;
  48   unsigned char *mod1, *mod2;
  49   unsigned char *p1, *p2;
  50
  51   for (off1 = 0; off1 < MAX_OFFSET; off1++)
  52     for (off2 = 0; off2 < MAX_OFFSET; off2++)
  53       for (len = 0; len < MAX_TEST; len++)
  54         {
  55           p1 = u1.buf;
  56           for (i = 0; i < off1; i++)
  57             *p1++ = '\0';
  58
  59           buf1 = p1;
  60           for (i = 0; i < len; i++)
  61             *p1++ = 'a';
  62
  63           mod1 = p1;
  64           for (i = 0; i < MAX_EXTRA; i++)
  65             *p1++ = 'x';
  66
  67           p2 = u2.buf;
  68           for (i = 0; i < off2; i++)
  69             *p2++ = '\0';
  70
  71           buf2 = p2;
  72           for (i = 0; i < len; i++)
  73             *p2++ = 'a';
  74
  75           mod2 = p2;
  76           for (i = 0; i < MAX_EXTRA; i++)
  77             *p2++ = 'x';
  78
  79           mod1[0] = '\0';
  80           mod2[0] = '\0';
  81           test (buf1, buf2, MAX_LENGTH, 0);
  82           test (buf1, buf2, len, 0);
  83
  84           mod1[0] = 'a';
  85           mod1[1] = '\0';
  86           mod2[0] = '\0';
  87           test (buf1, buf2, MAX_LENGTH, +1);
  88           test (buf1, buf2, len, 0);
  89
  90           mod1[0] = '\0';
  91           mod2[0] = 'a';
  92           mod2[1] = '\0';
  93           test (buf1, buf2, MAX_LENGTH, -1);
  94           test (buf1, buf2, len, 0);
  95
  96           mod1[0] = 'b';
  97           mod1[1] = '\0';
  98           mod2[0] = 'c';
  99           mod2[1] = '\0';
 100           test (buf1, buf2, MAX_LENGTH, -1);
 101           test (buf1, buf2, len, 0);
 102
 103           mod1[0] = 'c';
 104           mod1[1] = '\0';
 105           mod2[0] = 'b';
 106           mod2[1] = '\0';
 107           test (buf1, buf2, MAX_LENGTH, +1);
 108           test (buf1, buf2, len, 0);
 109
 110           mod1[0] = 'b';
 111           mod1[1] = '\0';
 112           mod2[0] = (unsigned char)'\251';
 113           mod2[1] = '\0';
 114           test (buf1, buf2, MAX_LENGTH, -1);
 115           test (buf1, buf2, len, 0);
 116
 117           mod1[0] = (unsigned char)'\251';
 118           mod1[1] = '\0';
 119           mod2[0] = 'b';
 120           mod2[1] = '\0';
 121           test (buf1, buf2, MAX_LENGTH, +1);
 122           test (buf1, buf2, len, 0);
 123
 124           mod1[0] = (unsigned char)'\251';
 125           mod1[1] = '\0';
 126           mod2[0] = (unsigned char)'\252';
 127           mod2[1] = '\0';
 128           test (buf1, buf2, MAX_LENGTH, -1);
 129           test (buf1, buf2, len, 0);
 130
 131           mod1[0] = (unsigned char)'\252';
 132           mod1[1] = '\0';
 133           mod2[0] = (unsigned char)'\251';
 134           mod2[1] = '\0';
 135           test (buf1, buf2, MAX_LENGTH, +1);
 136           test (buf1, buf2, len, 0);
 137         }
 138
 139   exit (0);
 140 }