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/* strncat( 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 * strncat( char * _PDCLIB_restrict s1, const char * _PDCLIB_restrict s2, size_t n )
{
    char * rc = s1;
    while ( *s1 )
    {
        ++s1;
    }
    while ( n && ( *s1++ = *s2++ ) )
    {
        --n;
    }
    if ( n == 0 )
    {
        *s1 = '\0';
    }
    return rc;
}

#endif

#ifdef TEST

#include "_PDCLIB_test.h"

int main( void )
{
    char s[] = "xx\0xxxxxx";
    TESTCASE( strncat( s, abcde, 10 ) == s );
    TESTCASE( s[2] == 'a' );
    TESTCASE( s[6] == 'e' );
    TESTCASE( s[7] == '\0' );
    TESTCASE( s[8] == 'x' );
    s[0] = '\0';
    TESTCASE( strncat( s, abcdx, 10 ) == s );
    TESTCASE( s[4] == 'x' );
    TESTCASE( s[5] == '\0' );
    TESTCASE( strncat( s, "\0", 10 ) == s );
    TESTCASE( s[5] == '\0' );
    TESTCASE( s[6] == 'e' );
    TESTCASE( strncat( s, abcde, 0 ) == s );
    TESTCASE( s[5] == '\0' );
    TESTCASE( s[6] == 'e' );
    TESTCASE( strncat( s, abcde, 3 ) == s );
    TESTCASE( s[5] == 'a' );
    TESTCASE( s[7] == 'c' );
    TESTCASE( s[8] == '\0' );
    return TEST_RESULTS;
}

#endif