2 * Copyright (C) 2004, 2007-2011 Free Software Foundation, Inc.
3 * Written by Bruno Haible and Eric Blake
5 * This program is free software: you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 3 of the License, or
8 * (at your option) any later version.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program. If not, see <http://www.gnu.org/licenses/>. */
22 #include "signature.h"
23 SIGNATURE_CHECK (strstr, char *, (char const *, char const *));
29 #include "zerosize-ptr.h"
33 main (int argc, char *argv[])
36 /* Declare failure if test takes too long, by using default abort
37 caused by SIGALRM. All known platforms that lack alarm also have
38 a quadratic strstr, and the replacement strstr is known to not
40 signal (SIGALRM, SIG_DFL);
45 const char input[] = "foo";
46 const char *result = strstr (input, "");
47 ASSERT (result == input);
51 const char input[] = "foo";
52 const char *result = strstr (input, "o");
53 ASSERT (result == input + 1);
57 /* On some platforms, the memchr() functions reads past the first
58 occurrence of the byte to be searched, leading to an out-of-bounds
59 read access for strstr().
60 See <http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=521737>.
61 This is a bug in memchr(), see the Austin Group's clarification
62 <http://www.opengroup.org/austin/docs/austin_454.txt>. */
63 const char *fix = "aBaaaaaaaaaaax";
64 char *page_boundary = (char *) zerosize_ptr ();
65 size_t len = strlen (fix) + 1;
66 char *input = page_boundary ? page_boundary - len : malloc (len);
70 result = strstr (input, "B1x");
71 ASSERT (result == NULL);
77 const char input[] = "ABC ABCDAB ABCDABCDABDE";
78 const char *result = strstr (input, "ABCDABD");
79 ASSERT (result == input + 15);
83 const char input[] = "ABC ABCDAB ABCDABCDABDE";
84 const char *result = strstr (input, "ABCDABE");
85 ASSERT (result == NULL);
89 const char input[] = "ABC ABCDAB ABCDABCDABDE";
90 const char *result = strstr (input, "ABCDABCD");
91 ASSERT (result == input + 11);
94 /* Check that a long periodic needle does not cause false positives. */
96 const char input[] = "F_BD_CE_BD_EF_BF_BD_EF_BF_BD_EF_BF_BD_EF_BF_BD"
97 "_C3_88_20_EF_BF_BD_EF_BF_BD_EF_BF_BD"
99 const char need[] = "_EF_BF_BD_EF_BF_BD_EF_BF_BD_EF_BF_BD_EF_BF_BD";
100 const char *result = strstr (input, need);
101 ASSERT (result == NULL);
104 const char input[] = "F_BD_CE_BD_EF_BF_BD_EF_BF_BD_EF_BF_BD_EF_BF_BD"
105 "_C3_88_20_EF_BF_BD_EF_BF_BD_EF_BF_BD"
106 "_C3_A7_20_EF_BF_BD_DA_B5_C2_A6_20"
107 "_EF_BF_BD_EF_BF_BD_EF_BF_BD_EF_BF_BD_EF_BF_BD";
108 const char need[] = "_EF_BF_BD_EF_BF_BD_EF_BF_BD_EF_BF_BD_EF_BF_BD";
109 const char *result = strstr (input, need);
110 ASSERT (result == input + 115);
113 /* Check that a very long haystack is handled quickly if the needle is
114 short and occurs near the beginning. */
116 size_t repeat = 10000;
119 "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
120 "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA";
121 char *haystack = (char *) malloc (m + 1);
122 if (haystack != NULL)
124 memset (haystack, 'A', m);
128 for (; repeat > 0; repeat--)
130 ASSERT (strstr (haystack, needle) == haystack + 1);
137 /* Check that a very long needle is discarded quickly if the haystack is
140 size_t repeat = 10000;
142 const char *haystack =
143 "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
144 "ABABABABABABABABABABABABABABABABABABABABABABABABABABABABABABABABABAB";
145 char *needle = (char *) malloc (m + 1);
148 memset (needle, 'A', m);
151 for (; repeat > 0; repeat--)
153 ASSERT (strstr (haystack, needle) == NULL);
160 /* Check that the asymptotic worst-case complexity is not quadratic. */
163 char *haystack = (char *) malloc (2 * m + 2);
164 char *needle = (char *) malloc (m + 2);
165 if (haystack != NULL && needle != NULL)
169 memset (haystack, 'A', 2 * m);
170 haystack[2 * m] = 'B';
171 haystack[2 * m + 1] = '\0';
173 memset (needle, 'A', m);
175 needle[m + 1] = '\0';
177 result = strstr (haystack, needle);
178 ASSERT (result == haystack + m);
184 /* Sublinear speed is only possible in memmem; strstr must examine
185 every character of haystack to find its length. */
189 /* Ensure that with a barely periodic "short" needle, strstr's
190 search does not mistakenly skip just past the match point.
191 This use of strstr would mistakenly return NULL before
193 const char *haystack =
195 "with_build_libsubdir\n"
196 "with_local_prefix\n"
197 "with_gxx_include_dir\n"
198 "with_cpp_install_dir\n"
199 "enable_generated_files_in_srcdir\n"
202 "with_demangler_in_ld\n"
206 "enable_werror_always\n"
209 "enable_gather_detailed_mem_stats\n"
210 "enable_build_with_cxx\n"
213 "enable___cxa_atexit\n"
214 "enable_decimal_float\n"
215 "enable_fixed_point\n"
221 "with_build_sysroot\n"
227 "with_multilib_list\n";
228 const char *needle = "\n"
230 const char* p = strstr (haystack, needle);
231 ASSERT (p - haystack == 114);
235 /* Same bug, shorter trigger. */
236 const char *haystack = "..wi.d.";
237 const char *needle = ".d.";
238 const char* p = strstr (haystack, needle);
239 ASSERT (p - haystack == 4);
243 /* Like the above, but trigger the flaw in two_way_long_needle
244 by using a needle of length LONG_NEEDLE_THRESHOLD (32) or greater.
245 Rather than trying to find the right alignment manually, I've
246 arbitrarily chosen the following needle and template for the
247 haystack, and ensure that for each placement of the needle in
248 that haystack, strstr finds it. */
249 const char *needle = "\nwith_gnu_ld-extend-to-len-32-b\n";
252 "with_build_libsubdir\n"
253 "with_local_prefix\n"
254 "with_gxx_include_dir\n"
255 "with_cpp_install_dir\n"
257 "..............................\n"
258 "with_FGHIJKLMNOPQRSTUVWXYZ\n"
259 "with_567890123456789\n"
260 "with_multilib_list\n";
261 size_t h_len = strlen (h);
262 char *haystack = malloc (h_len + 1);
265 for (i = 0; i < h_len - strlen (needle); i++)
268 memcpy (haystack, h, h_len + 1);
269 memcpy (haystack + i, needle, strlen (needle) + 1);
270 p = strstr (haystack, needle);
272 ASSERT (p - haystack == i);