tests/test-wcsncmp.c

   1 /* Test of wcsncmp() function.
   2    Copyright (C) 2010-2024 Free Software Foundation, Inc.
   3
   4    This program is free software: you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation, either version 3 of the License, or
   7    (at your option) any later version.
   8
   9    This program 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
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
  16
  17 /* Written by Bruno Haible <bruno@clisp.org>, 2023.  */
  18
  19 #include <config.h>
  20
  21 #include <wchar.h>
  22
  23 #include "signature.h"
  24 SIGNATURE_CHECK (wcsncmp, int, (const wchar_t *, const wchar_t *, size_t));
  25
  26 #include "macros.h"
  27
  28 int
  29 main (int argc, char *argv[])
  30 {
  31   /* Test simple cases.  */
  32   {
  33     static const wchar_t input1[] = { 0 };
  34     static const wchar_t input2[] = { 0 };
  35     ASSERT (wcsncmp (input1, input2, 0) == 0);
  36     ASSERT (wcsncmp (input1, input2, 1) == 0);
  37     ASSERT (wcsncmp (input1, input2, 1000000) == 0);
  38   }
  39   {
  40     static const wchar_t input1[] = { 0 };
  41     static const wchar_t input2[] = { 'f', 'o', 'o', 0 };
  42     ASSERT (wcsncmp (input1, input2, 0) == 0);
  43     ASSERT (wcsncmp (input1, input2, 1) < 0);
  44     ASSERT (wcsncmp (input2, input1, 1) > 0);
  45     ASSERT (wcsncmp (input1, input2, 3) < 0);
  46     ASSERT (wcsncmp (input2, input1, 3) > 0);
  47     ASSERT (wcsncmp (input1, input2, 4) < 0);
  48     ASSERT (wcsncmp (input2, input1, 4) > 0);
  49     ASSERT (wcsncmp (input1, input2, 1000000) < 0);
  50     ASSERT (wcsncmp (input2, input1, 1000000) > 0);
  51   }
  52   {
  53     static const wchar_t input1[] = { 'f', 'o', 'o', 0 };
  54     static const wchar_t input2[] = { 'f', 'o', 'o', 0 };
  55     ASSERT (wcsncmp (input1, input2, 0) == 0);
  56     ASSERT (wcsncmp (input1, input2, 1) == 0);
  57     ASSERT (wcsncmp (input1, input2, 2) == 0);
  58     ASSERT (wcsncmp (input1, input2, 3) == 0);
  59     ASSERT (wcsncmp (input1, input2, 4) == 0);
  60     ASSERT (wcsncmp (input1, input2, 1000000) == 0);
  61   }
  62   {
  63     static const wchar_t input1[] = { 'f', 'o', 'o', 0 };
  64     static const wchar_t input2[] = { 'b', 'a', 'r', 0 };
  65     ASSERT (wcsncmp (input1, input2, 0) == 0);
  66     ASSERT (wcsncmp (input1, input2, 1) > 0);
  67     ASSERT (wcsncmp (input2, input1, 1) < 0);
  68     ASSERT (wcsncmp (input1, input2, 2) > 0);
  69     ASSERT (wcsncmp (input2, input1, 2) < 0);
  70     ASSERT (wcsncmp (input1, input2, 1000000) > 0);
  71     ASSERT (wcsncmp (input2, input1, 1000000) < 0);
  72   }
  73   {
  74     static const wchar_t input1[] = { 'f', 'o', 'o', 0 };
  75     static const wchar_t input2[] = { 'f', 'o', 'o', 'b', 'a', 'r', 0 };
  76     ASSERT (wcsncmp (input1, input2, 0) == 0);
  77     ASSERT (wcsncmp (input1, input2, 1) == 0);
  78     ASSERT (wcsncmp (input1, input2, 2) == 0);
  79     ASSERT (wcsncmp (input1, input2, 3) == 0);
  80     ASSERT (wcsncmp (input1, input2, 4) < 0);
  81     ASSERT (wcsncmp (input2, input1, 4) > 0);
  82     ASSERT (wcsncmp (input1, input2, 1000000) < 0);
  83     ASSERT (wcsncmp (input2, input1, 1000000) > 0);
  84   }
  85   {
  86     static const wchar_t input1[] = { 'o', 'o', 'm', 'p', 'h', 0 };
  87     static const wchar_t input2[] = { 'o', 'o', 'p', 's', 0 };
  88     ASSERT (wcsncmp (input1, input2, 0) == 0);
  89     ASSERT (wcsncmp (input1, input2, 1) == 0);
  90     ASSERT (wcsncmp (input1, input2, 2) == 0);
  91     ASSERT (wcsncmp (input1, input2, 3) < 0);
  92     ASSERT (wcsncmp (input2, input1, 3) > 0);
  93     ASSERT (wcsncmp (input1, input2, 4) < 0);
  94     ASSERT (wcsncmp (input2, input1, 4) > 0);
  95     ASSERT (wcsncmp (input1, input2, 5) < 0);
  96     ASSERT (wcsncmp (input2, input1, 5) > 0);
  97     ASSERT (wcsncmp (input1, input2, 6) < 0);
  98     ASSERT (wcsncmp (input2, input1, 6) > 0);
  99     ASSERT (wcsncmp (input1, input2, 1000000) < 0);
 100     ASSERT (wcsncmp (input2, input1, 1000000) > 0);
 101   }
 102
 103   /* ISO C requires wcsncmp to work with all wchar_t values.
 104      ISO C 17 § 7.29.4.4 says:
 105        "Unless explicitly stated otherwise, the functions described in this
 106         subclause order two wide characters the same way as two integers of
 107         the underlying integer type designated by wchar_t."  */
 108   {
 109     static const wchar_t input1[] = { (wchar_t) 0x76547654, 0 };
 110     static const wchar_t input2[] = { (wchar_t) 0x9abc9abc, 0 };
 111     ASSERT (wcsncmp (input1, input2, 0) == 0);
 112     if ((wchar_t)-1 < 0)
 113       {
 114         /* wchar_t is signed.  */
 115         ASSERT (wcsncmp (input1, input2, 1) > 0);
 116         ASSERT (wcsncmp (input2, input1, 1) < 0);
 117         ASSERT (wcsncmp (input1, input2, 2) > 0);
 118         ASSERT (wcsncmp (input2, input1, 2) < 0);
 119         ASSERT (wcsncmp (input1, input2, 1000000) > 0);
 120         ASSERT (wcsncmp (input2, input1, 1000000) < 0);
 121       }
 122     else
 123       {
 124         /* wchar_t is unsigned.  */
 125         ASSERT (wcsncmp (input1, input2, 1) < 0);
 126         ASSERT (wcsncmp (input2, input1, 1) > 0);
 127         ASSERT (wcsncmp (input1, input2, 2) < 0);
 128         ASSERT (wcsncmp (input2, input1, 2) > 0);
 129         ASSERT (wcsncmp (input1, input2, 1000000) < 0);
 130         ASSERT (wcsncmp (input2, input1, 1000000) > 0);
 131       }
 132   }
 133   {
 134     static const wchar_t input1[] = { (wchar_t) 0x9abc9abc, 0 };
 135     static const wchar_t input2[] = { (wchar_t) 0x9bdf9bdf, 0 };
 136     ASSERT (wcsncmp (input1, input2, 0) == 0);
 137     ASSERT (wcsncmp (input1, input2, 1) < 0);
 138     ASSERT (wcsncmp (input2, input1, 1) > 0);
 139     ASSERT (wcsncmp (input1, input2, 2) < 0);
 140     ASSERT (wcsncmp (input2, input1, 2) > 0);
 141     ASSERT (wcsncmp (input1, input2, 1000000) < 0);
 142     ASSERT (wcsncmp (input2, input1, 1000000) > 0);
 143   }
 144
 145   /* Comparing a negative wchar_t value against a null wchar_t.
 146      ISO C 17 § 7.29.4.4.1 says:
 147        "The wcsncmp function compares the wide string pointed to by s1 to
 148         the wide string pointed to by s2."
 149      ISO C 17 § 7.1.1 defines the term "wide string":
 150        "A wide string is a contiguous sequence of wide characters terminated
 151         by and including the first null wide character."
 152      This means that the comparison extends up to and *including* the first
 153      null wchar_t.  */
 154   {
 155     static const wchar_t input1[] = { (wchar_t) 'x', 0 };
 156     static const wchar_t input2[] = { (wchar_t) 'x', (wchar_t) 0x9abc9abc, 0 };
 157     ASSERT (wcsncmp (input1, input2, 0) == 0);
 158     ASSERT (wcsncmp (input1, input2, 1) == 0);
 159     if ((wchar_t)-1 < 0)
 160       {
 161         /* wchar_t is signed.  */
 162         ASSERT (wcsncmp (input1, input2, 2) > 0);
 163         ASSERT (wcsncmp (input2, input1, 2) < 0);
 164         ASSERT (wcsncmp (input1, input2, 3) > 0);
 165         ASSERT (wcsncmp (input2, input1, 3) < 0);
 166         ASSERT (wcsncmp (input1, input2, 1000000) > 0);
 167         ASSERT (wcsncmp (input2, input1, 1000000) < 0);
 168       }
 169     else
 170       {
 171         /* wchar_t is unsigned.  */
 172         ASSERT (wcsncmp (input1, input2, 2) < 0);
 173         ASSERT (wcsncmp (input2, input1, 2) > 0);
 174         ASSERT (wcsncmp (input1, input2, 3) < 0);
 175         ASSERT (wcsncmp (input2, input1, 3) > 0);
 176         ASSERT (wcsncmp (input1, input2, 1000000) < 0);
 177         ASSERT (wcsncmp (input2, input1, 1000000) > 0);
 178       }
 179   }
 180
 181   return test_exit_status;
 182 }