gcc/testsuite/gcc.c-torture/execute/strncmp-1.c

   1 /* { dg-xfail-if "kernel strncmp does not perform unsigned comparisons" { vxworks_kernel } } */
   2 /* Copyright (C) 2002  Free Software Foundation.
   3
   4    Test strncmp with various combinations of pointer alignments and lengths to
   5    make sure any optimizations in the library are correct.
   6
   7    Written by Michael Meissner, March 9, 2002.  */
   8
   9 #include <string.h>
  10 #include <stddef.h>
  11
  12 #ifndef MAX_OFFSET
  13 #define MAX_OFFSET (sizeof (long long))
  14 #endif
  15
  16 #ifndef MAX_TEST
  17 #define MAX_TEST (8 * sizeof (long long))
  18 #endif
  19
  20 #ifndef MAX_EXTRA
  21 #define MAX_EXTRA (sizeof (long long))
  22 #endif
  23
  24 #define MAX_LENGTH (MAX_OFFSET + MAX_TEST + MAX_EXTRA)
  25
  26 static union {
  27   unsigned char buf[MAX_LENGTH];
  28   long long align_int;
  29   long double align_fp;
  30 } u1, u2;
  31
  32 void
  33 test (const unsigned char *s1, const unsigned char *s2, size_t len, int expected)
  34 {
  35   int value = strncmp ((char *) s1, (char *) s2, len);
  36
  37   if (expected < 0 && value >= 0)
  38     abort ();
  39   else if (expected == 0 && value != 0)
  40     abort ();
  41   else if (expected > 0 && value <= 0)
  42     abort ();
  43 }
  44
  45 main ()
  46 {
  47   size_t off1, off2, len, i;
  48   unsigned char *buf1, *buf2;
  49   unsigned char *mod1, *mod2;
  50   unsigned char *p1, *p2;
  51
  52   for (off1 = 0; off1 < MAX_OFFSET; off1++)
  53     for (off2 = 0; off2 < MAX_OFFSET; off2++)
  54       for (len = 0; len < MAX_TEST; len++)
  55         {
  56           p1 = u1.buf;
  57           for (i = 0; i < off1; i++)
  58             *p1++ = '\0';
  59
  60           buf1 = p1;
  61           for (i = 0; i < len; i++)
  62             *p1++ = 'a';
  63
  64           mod1 = p1;
  65           for (i = 0; i < MAX_EXTRA; i++)
  66             *p1++ = 'x';
  67
  68           p2 = u2.buf;
  69           for (i = 0; i < off2; i++)
  70             *p2++ = '\0';
  71
  72           buf2 = p2;
  73           for (i = 0; i < len; i++)
  74             *p2++ = 'a';
  75
  76           mod2 = p2;
  77           for (i = 0; i < MAX_EXTRA; i++)
  78             *p2++ = 'x';
  79
  80           mod1[0] = '\0';
  81           mod2[0] = '\0';
  82           test (buf1, buf2, MAX_LENGTH, 0);
  83           test (buf1, buf2, len, 0);
  84
  85           mod1[0] = 'a';
  86           mod1[1] = '\0';
  87           mod2[0] = '\0';
  88           test (buf1, buf2, MAX_LENGTH, +1);
  89           test (buf1, buf2, len, 0);
  90
  91           mod1[0] = '\0';
  92           mod2[0] = 'a';
  93           mod2[1] = '\0';
  94           test (buf1, buf2, MAX_LENGTH, -1);
  95           test (buf1, buf2, len, 0);
  96
  97           mod1[0] = 'b';
  98           mod1[1] = '\0';
  99           mod2[0] = 'c';
 100           mod2[1] = '\0';
 101           test (buf1, buf2, MAX_LENGTH, -1);
 102           test (buf1, buf2, len, 0);
 103
 104           mod1[0] = 'c';
 105           mod1[1] = '\0';
 106           mod2[0] = 'b';
 107           mod2[1] = '\0';
 108           test (buf1, buf2, MAX_LENGTH, +1);
 109           test (buf1, buf2, len, 0);
 110
 111           mod1[0] = 'b';
 112           mod1[1] = '\0';
 113           mod2[0] = (unsigned char)'\251';
 114           mod2[1] = '\0';
 115           test (buf1, buf2, MAX_LENGTH, -1);
 116           test (buf1, buf2, len, 0);
 117
 118           mod1[0] = (unsigned char)'\251';
 119           mod1[1] = '\0';
 120           mod2[0] = 'b';
 121           mod2[1] = '\0';
 122           test (buf1, buf2, MAX_LENGTH, +1);
 123           test (buf1, buf2, len, 0);
 124
 125           mod1[0] = (unsigned char)'\251';
 126           mod1[1] = '\0';
 127           mod2[0] = (unsigned char)'\252';
 128           mod2[1] = '\0';
 129           test (buf1, buf2, MAX_LENGTH, -1);
 130           test (buf1, buf2, len, 0);
 131
 132           mod1[0] = (unsigned char)'\252';
 133           mod1[1] = '\0';
 134           mod2[0] = (unsigned char)'\251';
 135           mod2[1] = '\0';
 136           test (buf1, buf2, MAX_LENGTH, +1);
 137           test (buf1, buf2, len, 0);
 138         }
 139
 140   exit (0);
 141 }