2 * Copyright (C) 2004, 2007, 2008 Free Software Foundation
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/>. */
26 #define ASSERT(expr) \
31 fprintf (stderr, "%s:%d: assertion failed\n", __FILE__, __LINE__); \
38 main (int argc, char *argv[])
41 /* Declare failure if test takes too long, by using default abort
42 caused by SIGALRM. All known platforms that lack alarm also have
43 a quadratic strstr, and the replacement strstr is known to not
49 const char input[] = "foo";
50 const char *result = strstr (input, "");
51 ASSERT (result == input);
55 const char input[] = "foo";
56 const char *result = strstr (input, "o");
57 ASSERT (result == input + 1);
61 const char input[] = "ABC ABCDAB ABCDABCDABDE";
62 const char *result = strstr (input, "ABCDABD");
63 ASSERT (result == input + 15);
67 const char input[] = "ABC ABCDAB ABCDABCDABDE";
68 const char *result = strstr (input, "ABCDABE");
69 ASSERT (result == NULL);
73 const char input[] = "ABC ABCDAB ABCDABCDABDE";
74 const char *result = strstr (input, "ABCDABCD");
75 ASSERT (result == input + 11);
78 /* Check that a very long haystack is handled quickly if the needle is
79 short and occurs near the beginning. */
81 size_t repeat = 10000;
84 "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
85 "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA";
86 char *haystack = (char *) malloc (m + 1);
89 memset (haystack, 'A', m);
93 for (; repeat > 0; repeat--)
95 ASSERT (strstr (haystack, needle) == haystack + 1);
102 /* Check that a very long needle is discarded quickly if the haystack is
105 size_t repeat = 10000;
108 "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
109 "ABABABABABABABABABABABABABABABABABABABABABABABABABABABABABABABABABAB";
110 char *needle = (char *) malloc (m + 1);
113 memset (needle, 'A', m);
116 for (; repeat > 0; repeat--)
118 ASSERT (strstr (haystack, needle) == NULL);
125 /* Check that the asymptotic worst-case complexity is not quadratic. */
128 char *haystack = (char *) malloc (2 * m + 2);
129 char *needle = (char *) malloc (m + 2);
130 if (haystack != NULL && needle != NULL)
134 memset (haystack, 'A', 2 * m);
135 haystack[2 * m] = 'B';
136 haystack[2 * m + 1] = '\0';
138 memset (needle, 'A', m);
140 needle[m + 1] = '\0';
142 result = strstr (haystack, needle);
143 ASSERT (result == haystack + m);
147 if (haystack != NULL)
151 /* Sublinear speed is only possible in memmem; strstr must examine
152 every character of haystack to find its length. */