ack/lang/cem/libcc.ansi/core/string/strncmp.c
David Given d1cdb07719 Realise that the libc core can safely call other libc core functions, even if
they're not defined in the core: so putw() can call stdio stuff, for example.
So the earlier concept of pureness isn't necessary. Rename accordingly.
2018-06-21 23:24:23 +02:00

31 lines
548 B
C

/*
* (c) copyright 1987 by the Vrije Universiteit, Amsterdam, The Netherlands.
* See the copyright notice in the ACK home directory, in the file "Copyright".
*/
/* $Id$ */
#include <string.h>
int strncmp(register const char* s1, register const char* s2, register size_t n)
{
if (n)
{
do
{
if (*s1 != *s2++)
break;
if (*s1++ == '\0')
return 0;
} while (--n > 0);
if (n > 0)
{
if (*s1 == '\0')
return -1;
if (*--s2 == '\0')
return 1;
return (unsigned char)*s1 - (unsigned char)*s2;
}
}
return 0;
}