1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
|
/* strstr( const char *, const char * )
This file is part of the Public Domain C Library (PDCLib).
Permission is granted to use, modify, and / or redistribute at will.
*/
#include <string.h>
#ifndef REGTEST
char * strstr( const char * s1, const char * s2 )
{
const char * p1 = s1;
const char * p2;
while ( *s1 )
{
p2 = s2;
while ( *p2 && ( *p1 == *p2 ) )
{
++p1;
++p2;
}
if ( ! *p2 )
{
return ( char * ) s1;
}
++s1;
p1 = s1;
}
return NULL;
}
#endif
#ifdef TEST
#include "_PDCLIB_test.h"
int main( void )
{
char s[] = "abcabcabcdabcde";
TESTCASE( strstr( s, "x" ) == NULL );
TESTCASE( strstr( s, "xyz" ) == NULL );
TESTCASE( strstr( s, "a" ) == &s[0] );
TESTCASE( strstr( s, "abc" ) == &s[0] );
TESTCASE( strstr( s, "abcd" ) == &s[6] );
TESTCASE( strstr( s, "abcde" ) == &s[10] );
return TEST_RESULTS;
}
#endif
|
