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/*
* Copyright (C) 2004, 2007, 2008 Free Software Foundation
* Written by Bruno Haible and Eric Blake
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include <config.h>
#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#define ASSERT(expr) \
do \
{ \
if (!(expr)) \
{ \
fprintf (stderr, "%s:%d: assertion failed\n", __FILE__, __LINE__); \
fflush (stderr); \
abort (); \
} \
} \
while (0)
int
main (int argc, char *argv[])
{
#if HAVE_DECL_ALARM
/* Declare failure if test takes too long, by using default abort
caused by SIGALRM. All known platforms that lack alarm also have
a quadratic strstr, and the replacement strstr is known to not
take too long. */
alarm (50);
#endif
{
const char input[] = "foo";
const char *result = strstr (input, "");
ASSERT (result == input);
}
{
const char input[] = "foo";
const char *result = strstr (input, "o");
ASSERT (result == input + 1);
}
{
const char input[] = "ABC ABCDAB ABCDABCDABDE";
const char *result = strstr (input, "ABCDABD");
ASSERT (result == input + 15);
}
{
const char input[] = "ABC ABCDAB ABCDABCDABDE";
const char *result = strstr (input, "ABCDABE");
ASSERT (result == NULL);
}
{
const char input[] = "ABC ABCDAB ABCDABCDABDE";
const char *result = strstr (input, "ABCDABCD");
ASSERT (result == input + 11);
}
/* Check that a very long haystack is handled quickly if the needle is
short and occurs near the beginning. */
{
size_t repeat = 10000;
size_t m = 1000000;
char *needle =
"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA";
char *haystack = (char *) malloc (m + 1);
if (haystack != NULL)
{
memset (haystack, 'A', m);
haystack[0] = 'B';
haystack[m] = '\0';
for (; repeat > 0; repeat--)
{
ASSERT (strstr (haystack, needle) == haystack + 1);
}
free (haystack);
}
}
/* Check that a very long needle is discarded quickly if the haystack is
short. */
{
size_t repeat = 10000;
size_t m = 1000000;
char *haystack =
"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
"ABABABABABABABABABABABABABABABABABABABABABABABABABABABABABABABABABAB";
char *needle = (char *) malloc (m + 1);
if (needle != NULL)
{
memset (needle, 'A', m);
needle[m] = '\0';
for (; repeat > 0; repeat--)
{
ASSERT (strstr (haystack, needle) == NULL);
}
free (needle);
}
}
/* Check that the asymptotic worst-case complexity is not quadratic. */
{
size_t m = 1000000;
char *haystack = (char *) malloc (2 * m + 2);
char *needle = (char *) malloc (m + 2);
if (haystack != NULL && needle != NULL)
{
const char *result;
memset (haystack, 'A', 2 * m);
haystack[2 * m] = 'B';
haystack[2 * m + 1] = '\0';
memset (needle, 'A', m);
needle[m] = 'B';
needle[m + 1] = '\0';
result = strstr (haystack, needle);
ASSERT (result == haystack + m);
}
free (needle);
free (haystack);
}
/* Sublinear speed is only possible in memmem; strstr must examine
every character of haystack to find its length. */
return 0;
}
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