helos1/libc/memcmp.c
2021-10-10 14:11:45 +08:00

47 lines
875 B
C

/* memcmp( const void *, const void *, size_t )
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
int memcmp( const void * s1, const void * s2, size_t n )
{
const unsigned char * p1 = ( const unsigned char * ) s1;
const unsigned char * p2 = ( const unsigned char * ) s2;
while ( n-- )
{
if ( *p1 != *p2 )
{
return *p1 - *p2;
}
++p1;
++p2;
}
return 0;
}
#endif
#ifdef TEST
#include "_PDCLIB_test.h"
int main( void )
{
const char xxxxx[] = "xxxxx";
TESTCASE( memcmp( abcde, abcdx, 5 ) < 0 );
TESTCASE( memcmp( abcde, abcdx, 4 ) == 0 );
TESTCASE( memcmp( abcde, xxxxx, 0 ) == 0 );
TESTCASE( memcmp( xxxxx, abcde, 1 ) > 0 );
return 0;
}
#endif