allascii.c revision 1.2 
1/*	$NetBSD: allascii.c,v 1.2 2017/02/14 01:16:48 christos Exp $	*/
2
3/*++
4/* NAME
5/*	allascii 3
6/* SUMMARY
7/*	predicate if string is all ASCII
8/* SYNOPSIS
9/*	#include <stringops.h>
10/*
11/*	int	allascii(buffer)
12/*	const char *buffer;
13/*
14/*	int	allascii_len(buffer, len)
15/*	const char *buffer;
16/*	ssize_t	len;
17/* DESCRIPTION
18/*	allascii() determines if its argument is an all-ASCII string.
19/*
20/*	Arguments:
21/* .IP buffer
22/*	The null-terminated input string.
23/* .IP len
24/*	The string length, -1 to determine the length dynamically.
25/* LICENSE
26/* .ad
27/* .fi
28/*	The Secure Mailer license must be distributed with this software.
29/* AUTHOR(S)
30/*	Wietse Venema
31/*	IBM T.J. Watson Research
32/*	P.O. Box 704
33/*	Yorktown Heights, NY 10598, USA
34/*--*/
35
36/* System library. */
37
38#include <sys_defs.h>
39#include <ctype.h>
40#include <string.h>
41
42/* Utility library. */
43
44#include "stringops.h"
45
46/* allascii_len - return true if string is all ASCII */
47
48int     allascii_len(const char *string, ssize_t len)
49{
50    const char *cp;
51    int     ch;
52
53    if (len < 0)
54	len = strlen(string);
55    if (len == 0)
56	return (0);
57    for (cp = string; cp < string + len
58	 && (ch = *(unsigned char *) cp) != 0; cp++)
59	if (!ISASCII(ch))
60	    return (0);
61    return (1);
62}
63