xref: /netbsd-src/lib/libc/gen/getttyent.c (revision 2a399c6883d870daece976daec6ffa7bb7f934ce)
1 /*	$NetBSD: getttyent.c,v 1.12 1997/10/20 08:07:51 scottr Exp $	*/
2 
3 /*
4  * Copyright (c) 1989, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by the University of
18  *	California, Berkeley and its contributors.
19  * 4. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #include <sys/cdefs.h>
37 #if defined(LIBC_SCCS) && !defined(lint)
38 #if 0
39 static char sccsid[] = "@(#)getttyent.c	8.1 (Berkeley) 6/4/93";
40 #else
41 __RCSID("$NetBSD: getttyent.c,v 1.12 1997/10/20 08:07:51 scottr Exp $");
42 #endif
43 #endif /* LIBC_SCCS and not lint */
44 
45 #include "namespace.h"
46 #include <ttyent.h>
47 #include <stdio.h>
48 #include <ctype.h>
49 #include <string.h>
50 
51 #ifdef __weak_alias
52 __weak_alias(endttyent,_endttyent);
53 __weak_alias(getttyent,_getttyent);
54 __weak_alias(getttynam,_getttynam);
55 __weak_alias(setttyent,_setttyent);
56 #endif
57 
58 static char zapchar;
59 static FILE *tf;
60 static char *skip __P((char *));
61 static char *value __P((char *));
62 
63 struct ttyent *
64 getttynam(tty)
65 	const char *tty;
66 {
67 	register struct ttyent *t;
68 
69 	setttyent();
70 	while ((t = getttyent()) != NULL)
71 		if (!strcmp(tty, t->ty_name))
72 			break;
73 	endttyent();
74 	return (t);
75 }
76 
77 struct ttyent *
78 getttyent()
79 {
80 	static struct ttyent tty;
81 	register int c;
82 	register char *p;
83 #define	MAXLINELENGTH	200
84 	static char line[MAXLINELENGTH];
85 
86 	if (!tf && !setttyent())
87 		return (NULL);
88 	for (;;) {
89 		if (!fgets(p = line, sizeof(line), tf))
90 			return (NULL);
91 		/* skip lines that are too big */
92 		if (!strchr(p, '\n')) {
93 			while ((c = getc(tf)) != '\n' && c != EOF)
94 				;
95 			continue;
96 		}
97 		while (isspace(*p))
98 			++p;
99 		if (*p && *p != '#')
100 			break;
101 	}
102 
103 	zapchar = 0;
104 	tty.ty_name = p;
105 	p = skip(p);
106 	if (!*(tty.ty_getty = p))
107 		tty.ty_getty = tty.ty_type = NULL;
108 	else {
109 		p = skip(p);
110 		if (!*(tty.ty_type = p))
111 			tty.ty_type = NULL;
112 		else
113 			p = skip(p);
114 	}
115 	tty.ty_status = 0;
116 	tty.ty_window = NULL;
117 
118 #define	scmp(e)	!strncmp(p, e, sizeof(e) - 1) && isspace(p[sizeof(e) - 1])
119 #define	vcmp(e)	!strncmp(p, e, sizeof(e) - 1) && p[sizeof(e) - 1] == '='
120 	for (; *p; p = skip(p)) {
121 		if (scmp(_TTYS_OFF))
122 			tty.ty_status &= ~TTY_ON;
123 		else if (scmp(_TTYS_ON))
124 			tty.ty_status |= TTY_ON;
125 		else if (scmp(_TTYS_SECURE))
126 			tty.ty_status |= TTY_SECURE;
127 		else if (scmp(_TTYS_LOCAL))
128 			tty.ty_status |= TTY_LOCAL;
129 		else if (scmp(_TTYS_RTSCTS))
130 			tty.ty_status |= TTY_RTSCTS;
131 		else if (scmp(_TTYS_DTRCTS))
132 			tty.ty_status |= TTY_DTRCTS;
133 		else if (scmp(_TTYS_SOFTCAR))
134 			tty.ty_status |= TTY_SOFTCAR;
135 		else if (scmp(_TTYS_MDMBUF))
136 			tty.ty_status |= TTY_MDMBUF;
137 		else if (vcmp(_TTYS_WINDOW))
138 			tty.ty_window = value(p);
139 		else
140 			break;
141 	}
142 
143 	if (zapchar == '#' || *p == '#')
144 		while ((c = *++p) == ' ' || c == '\t')
145 			;
146 	tty.ty_comment = p;
147 	if (*p == 0)
148 		tty.ty_comment = 0;
149 	if ((p = strchr(p, '\n')) != NULL)
150 		*p = '\0';
151 	return (&tty);
152 }
153 
154 #define	QUOTED	1
155 
156 /*
157  * Skip over the current field, removing quotes, and return a pointer to
158  * the next field.
159  */
160 static char *
161 skip(p)
162 	register char *p;
163 {
164 	register char *t;
165 	register int c, q;
166 
167 	for (q = 0, t = p; (c = *p) != '\0'; p++) {
168 		if (c == '"') {
169 			q ^= QUOTED;	/* obscure, but nice */
170 			continue;
171 		}
172 		if (q == QUOTED && *p == '\\' && *(p+1) == '"')
173 			p++;
174 		*t++ = *p;
175 		if (q == QUOTED)
176 			continue;
177 		if (c == '#') {
178 			zapchar = c;
179 			*p = 0;
180 			break;
181 		}
182 		if (c == '\t' || c == ' ' || c == '\n') {
183 			zapchar = c;
184 			*p++ = 0;
185 			while ((c = *p) == '\t' || c == ' ' || c == '\n')
186 				p++;
187 			break;
188 		}
189 	}
190 	*--t = '\0';
191 	return (p);
192 }
193 
194 static char *
195 value(p)
196 	register char *p;
197 {
198 
199 	return ((p = strchr(p, '=')) ? ++p : NULL);
200 }
201 
202 int
203 setttyent()
204 {
205 
206 	if (tf) {
207 		rewind(tf);
208 		return (1);
209 	} else if ((tf = fopen(_PATH_TTYS, "r")) != NULL)
210 		return (1);
211 	return (0);
212 }
213 
214 int
215 endttyent()
216 {
217 	int rval;
218 
219 	if (tf) {
220 		rval = !(fclose(tf) == EOF);
221 		tf = NULL;
222 		return (rval);
223 	}
224 	return (1);
225 }
226