tests/test-strcasestr.c

   1 /* Test of case-insensitive searching in a string.
   2    Copyright (C) 2007-2020 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>, 2007.  */
  18
  19 #include <config.h>
  20
  21 #include <string.h>
  22
  23 #include "signature.h"
  24 SIGNATURE_CHECK (strcasestr, char *, (char const *, char const *));
  25
  26 #include <signal.h>
  27 #include <stdlib.h>
  28 #include <unistd.h>
  29
  30 #include "macros.h"
  31
  32 int
  33 main ()
  34 {
  35 #if HAVE_DECL_ALARM
  36   /* Declare failure if test takes too long, by using default abort
  37      caused by SIGALRM.  All known platforms that lack alarm also lack
  38      strcasestr, and the replacement strcasestr is known to not take too
  39      long.  */
  40   int alarm_value = 50;
  41   signal (SIGALRM, SIG_DFL);
  42   alarm (alarm_value);
  43 #endif
  44
  45   {
  46     const char input[] = "foo";
  47     const char *result = strcasestr (input, "");
  48     ASSERT (result == input);
  49   }
  50
  51   {
  52     const char input[] = "foo";
  53     const char *result = strcasestr (input, "O");
  54     ASSERT (result == input + 1);
  55   }
  56
  57   {
  58     const char input[] = "ABC ABCDAB ABCDABCDABDE";
  59     const char *result = strcasestr (input, "ABCDaBD");
  60     ASSERT (result == input + 15);
  61   }
  62
  63   {
  64     const char input[] = "ABC ABCDAB ABCDABCDABDE";
  65     const char *result = strcasestr (input, "ABCDaBE");
  66     ASSERT (result == NULL);
  67   }
  68
  69   {
  70     const char input[] = "ABC ABCDAB ABCDABCDABDE";
  71     const char *result = strcasestr (input, "ABCDaBCD");
  72     ASSERT (result == input + 11);
  73   }
  74
  75   /* Check that a long periodic needle does not cause false positives.  */
  76   {
  77     const char input[] = "F_BD_CE_BD_EF_BF_BD_EF_BF_BD_EF_BF_BD_EF_BF_BD"
  78                          "_C3_88_20_EF_BF_BD_EF_BF_BD_EF_BF_BD"
  79                          "_C3_A7_20_EF_BF_BD";
  80     const char need[] = "_EF_BF_BD_EF_BF_BD_EF_BF_BD_EF_BF_BD_EF_BF_BD";
  81     const char *result = strcasestr (input, need);
  82     ASSERT (result == NULL);
  83   }
  84   {
  85     const char input[] = "F_BD_CE_BD_EF_BF_BD_EF_BF_BD_EF_BF_BD_EF_BF_BD"
  86                          "_C3_88_20_EF_BF_BD_EF_BF_BD_EF_BF_BD"
  87                          "_C3_A7_20_EF_BF_BD_DA_B5_C2_A6_20"
  88                          "_EF_BF_BD_EF_BF_BD_EF_BF_BD_EF_BF_BD_EF_BF_BD";
  89     const char need[] = "_EF_BF_BD_EF_BF_BD_EF_BF_BD_EF_BF_BD_EF_BF_BD";
  90     const char *result = strcasestr (input, need);
  91     ASSERT (result == input + 115);
  92   }
  93
  94   /* Check that a very long haystack is handled quickly if the needle is
  95      short and occurs near the beginning.  */
  96   {
  97     size_t repeat = 10000;
  98     size_t m = 1000000;
  99     const char *needle =
 100       "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
 101       "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaAaaaaaaAAAAaaaaaaa"
 102       "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA";
 103     char *haystack = (char *) malloc (m + 1);
 104     if (haystack != NULL)
 105       {
 106         memset (haystack, 'A', m);
 107         haystack[0] = 'B';
 108         haystack[m] = '\0';
 109
 110         for (; repeat > 0; repeat--)
 111           {
 112             ASSERT (strcasestr (haystack, needle) == haystack + 1);
 113           }
 114
 115         free (haystack);
 116       }
 117   }
 118
 119   /* Check that a very long needle is discarded quickly if the haystack is
 120      short.  */
 121   {
 122     size_t repeat = 10000;
 123     size_t m = 1000000;
 124     const char *haystack =
 125       "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
 126       "ABABABABABABABABABABABABABABABABABABABABABABABABABABABABABABABABABAB";
 127     char *needle = (char *) malloc (m + 1);
 128     if (needle != NULL)
 129       {
 130         memset (needle, 'A', m);
 131         needle[m] = '\0';
 132
 133         for (; repeat > 0; repeat--)
 134           {
 135             ASSERT (strcasestr (haystack, needle) == NULL);
 136           }
 137
 138         free (needle);
 139       }
 140   }
 141
 142   /* Check that the asymptotic worst-case complexity is not quadratic.  */
 143   {
 144     size_t m = 1000000;
 145     char *haystack = (char *) malloc (2 * m + 2);
 146     char *needle = (char *) malloc (m + 2);
 147     if (haystack != NULL && needle != NULL)
 148       {
 149         const char *result;
 150
 151         memset (haystack, 'A', 2 * m);
 152         haystack[2 * m] = 'B';
 153         haystack[2 * m + 1] = '\0';
 154
 155         memset (needle, 'a', m);
 156         needle[m] = 'B';
 157         needle[m + 1] = '\0';
 158
 159         result = strcasestr (haystack, needle);
 160         ASSERT (result == haystack + m);
 161       }
 162     free (needle);
 163     free (haystack);
 164   }
 165
 166   {
 167     /* Ensure that with a barely periodic "short" needle, strcasestr's
 168        search does not mistakenly skip just past the match point.
 169        This use of strcasestr would mistakenly return NULL before
 170        gnulib v0.0-4927.  */
 171     const char *haystack =
 172       "\n"
 173       "with_build_libsubdir\n"
 174       "with_local_prefix\n"
 175       "with_gxx_include_dir\n"
 176       "with_cpp_install_dir\n"
 177       "enable_generated_files_in_srcdir\n"
 178       "with_gnu_ld\n"
 179       "with_ld\n"
 180       "with_demangler_in_ld\n"
 181       "with_gnu_as\n"
 182       "with_as\n"
 183       "enable_largefile\n"
 184       "enable_werror_always\n"
 185       "enable_checking\n"
 186       "enable_coverage\n"
 187       "enable_gather_detailed_mem_stats\n"
 188       "enable_build_with_cxx\n"
 189       "with_stabs\n"
 190       "enable_multilib\n"
 191       "enable___cxa_atexit\n"
 192       "enable_decimal_float\n"
 193       "enable_fixed_point\n"
 194       "enable_threads\n"
 195       "enable_tls\n"
 196       "enable_objc_gc\n"
 197       "with_dwarf2\n"
 198       "enable_shared\n"
 199       "with_build_sysroot\n"
 200       "with_sysroot\n"
 201       "with_specs\n"
 202       "with_pkgversion\n"
 203       "with_bugurl\n"
 204       "enable_languages\n"
 205       "with_multilib_list\n";
 206     const char *needle = "\n"
 207       "with_GNU_ld\n";
 208     const char* p = strcasestr (haystack, needle);
 209     ASSERT (p - haystack == 114);
 210   }
 211
 212   {
 213     /* Same bug, shorter trigger.  */
 214     const char *haystack = "..wi.D.";
 215     const char *needle = ".d.";
 216     const char* p = strcasestr (haystack, needle);
 217     ASSERT (p - haystack == 4);
 218   }
 219
 220   {
 221     /* Like the above, but trigger the flaw in two_way_long_needle
 222        by using a needle of length LONG_NEEDLE_THRESHOLD (32) or greater.
 223        Rather than trying to find the right alignment manually, I've
 224        arbitrarily chosen the following needle and template for the
 225        haystack, and ensure that for each placement of the needle in
 226        that haystack, strcasestr finds it.  */
 227     const char *needle = "\nwith_gnu_ld-extend-to-len-32-b\n";
 228     const char *h =
 229       "\n"
 230       "with_build_libsubdir\n"
 231       "with_local_prefix\n"
 232       "with_gxx_include_dir\n"
 233       "with_cpp_install_dir\n"
 234       "with_e_\n"
 235       "..............................\n"
 236       "with_FGHIJKLMNOPQRSTUVWXYZ\n"
 237       "with_567890123456789\n"
 238       "with_multilib_list\n";
 239     size_t h_len = strlen (h);
 240     char *haystack = malloc (h_len + 1);
 241     size_t i;
 242     ASSERT (haystack);
 243     for (i = 0; i < h_len - strlen (needle); i++)
 244       {
 245         const char *p;
 246         memcpy (haystack, h, h_len + 1);
 247         memcpy (haystack + i, needle, strlen (needle) + 1);
 248         p = strcasestr (haystack, needle);
 249         ASSERT (p);
 250         ASSERT (p - haystack == i);
 251       }
 252     free (haystack);
 253   }
 254
 255   /* Test long needles.  */
 256   {
 257     size_t m = 1024;
 258     char *haystack = (char *) malloc (2 * m + 1);
 259     char *needle = (char *) malloc (m + 1);
 260     if (haystack != NULL && needle != NULL)
 261       {
 262         const char *p;
 263         haystack[0] = 'x';
 264         memset (haystack + 1, ' ', m - 1);
 265         memset (haystack + m, 'x', m);
 266         haystack[2 * m] = '\0';
 267         memset (needle, 'X', m);
 268         needle[m] = '\0';
 269         p = strcasestr (haystack, needle);
 270         ASSERT (p);
 271         ASSERT (p - haystack == m);
 272       }
 273     free (needle);
 274     free (haystack);
 275   }
 276
 277   return 0;
 278 }