60 lines
1.3 KiB
C
60 lines
1.3 KiB
C
/* strncpy( char *, const char *, 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
|
|
|
|
char * strncpy( char * s1, const char * s2, size_t n )
|
|
{
|
|
char * rc = s1;
|
|
|
|
while ( n && ( *s1++ = *s2++ ) )
|
|
{
|
|
/* Cannot do "n--" in the conditional as size_t is unsigned and we have
|
|
to check it again for >0 in the next loop below, so we must not risk
|
|
underflow.
|
|
*/
|
|
--n;
|
|
}
|
|
|
|
/* Checking against 1 as we missed the last --n in the loop above. */
|
|
while ( n-- > 1 )
|
|
{
|
|
*s1++ = '\0';
|
|
}
|
|
|
|
return rc;
|
|
}
|
|
|
|
#endif
|
|
|
|
#ifdef TEST
|
|
|
|
#include "_PDCLIB_test.h"
|
|
|
|
int main( void )
|
|
{
|
|
char s[] = "xxxxxxx";
|
|
TESTCASE( strncpy( s, "", 1 ) == s );
|
|
TESTCASE( s[0] == '\0' );
|
|
TESTCASE( s[1] == 'x' );
|
|
TESTCASE( strncpy( s, abcde, 6 ) == s );
|
|
TESTCASE( s[0] == 'a' );
|
|
TESTCASE( s[4] == 'e' );
|
|
TESTCASE( s[5] == '\0' );
|
|
TESTCASE( s[6] == 'x' );
|
|
TESTCASE( strncpy( s, abcde, 7 ) == s );
|
|
TESTCASE( s[6] == '\0' );
|
|
TESTCASE( strncpy( s, "xxxx", 3 ) == s );
|
|
TESTCASE( s[0] == 'x' );
|
|
TESTCASE( s[2] == 'x' );
|
|
TESTCASE( s[3] == 'd' );
|
|
return TEST_RESULTS;
|
|
}
|
|
|
|
#endif
|