1/*
2 * getopt - get option letter from argv
3 *
4 * This is a version of the public domain getopt() implementation by
5 * Henry Spencer, changed for 4.3BSD compatibility (in addition to System V).
6 * It allows rescanning of an option list by setting optind to 0 before
7 * calling, which is why we use it even if the system has its own (in fact,
8 * this one has a unique name so as not to conflict with the system's).
9 * Thanks to Dennis Ferguson for the appropriate modifications.
10 *
11 * This file is in the Public Domain.
12 */
13
14/*LINTLIBRARY*/
15
16#include <stdio.h>
17
18#include "ntp_stdlib.h"
19
20#ifdef	lint
21#undef	putc
22#define	putc	fputc
23#endif	/* lint */
24
25char	*ntp_optarg;	/* Global argument pointer. */
26int	ntp_optind = 0;	/* Global argv index. */
27int	ntp_opterr = 1;	/* for compatibility, should error be printed? */
28int	ntp_optopt;	/* for compatibility, option character checked */
29
30static char	*scan = NULL;	/* Private scan pointer. */
31static const char	*prog = "amnesia";
32
33/*
34 * Print message about a bad option.
35 */
36static int
37badopt(
38	const char *mess,
39	int ch
40	)
41{
42	if (ntp_opterr) {
43		fputs(prog, stderr);
44		fputs(mess, stderr);
45		(void) putc(ch, stderr);
46		(void) putc('\n', stderr);
47	}
48	return ('?');
49}
50
51int
52ntp_getopt(
53	int argc,
54	char *argv[],
55	const char *optstring
56	)
57{
58	register char c;
59	register const char *place;
60
61	prog = argv[0];
62	ntp_optarg = NULL;
63
64	if (ntp_optind == 0) {
65		scan = NULL;
66		ntp_optind++;
67	}
68
69	if (scan == NULL || *scan == '\0') {
70		if (ntp_optind >= argc
71		    || argv[ntp_optind][0] != '-'
72		    || argv[ntp_optind][1] == '\0') {
73			return (EOF);
74		}
75		if (argv[ntp_optind][1] == '-'
76		    && argv[ntp_optind][2] == '\0') {
77			ntp_optind++;
78			return (EOF);
79		}
80
81		scan = argv[ntp_optind++]+1;
82	}
83
84	c = *scan++;
85	ntp_optopt = c & 0377;
86	for (place = optstring; place != NULL && *place != '\0'; ++place)
87	    if (*place == c)
88		break;
89
90	if (place == NULL || *place == '\0' || c == ':' || c == '?') {
91		return (badopt(": unknown option -", c));
92	}
93
94	place++;
95	if (*place == ':') {
96		if (*scan != '\0') {
97			ntp_optarg = scan;
98			scan = NULL;
99		} else if (ntp_optind >= argc) {
100			return (badopt(": option requires argument -", c));
101		} else {
102			ntp_optarg = argv[ntp_optind++];
103		}
104	}
105
106	return (c & 0377);
107}
108