xref: /openbsd-src/lib/libc/gen/getttyent.c (revision b2ea75c1b17e1a9a339660e7ed45cd24946b230e)
1 /*
2  * Copyright (c) 1989, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #if defined(LIBC_SCCS) && !defined(lint)
35 static char rcsid[] = "$OpenBSD: getttyent.c,v 1.4 1997/07/09 00:28:22 millert Exp $";
36 #endif /* LIBC_SCCS and not lint */
37 
38 #include <ttyent.h>
39 #include <stdio.h>
40 #include <ctype.h>
41 #include <string.h>
42 
43 static char zapchar;
44 static FILE *tf;
45 
46 static char *skip __P((char *));
47 static char *value __P((char *));
48 
49 struct ttyent *
50 getttynam(tty)
51 	const char *tty;
52 {
53 	register struct ttyent *t;
54 
55 	setttyent();
56 	while ((t = getttyent()))
57 		if (!strcmp(tty, t->ty_name))
58 			break;
59 	endttyent();
60 	return (t);
61 }
62 
63 struct ttyent *
64 getttyent()
65 {
66 	static struct ttyent tty;
67 	register int c;
68 	register char *p;
69 #define	MAXLINELENGTH	200
70 	static char line[MAXLINELENGTH];
71 
72 	if (!tf && !setttyent())
73 		return (NULL);
74 	for (;;) {
75 		if (!fgets(p = line, sizeof(line), tf))
76 			return (NULL);
77 		/* skip lines that are too big */
78 		if (!strchr(p, '\n')) {
79 			while ((c = getc(tf)) != '\n' && c != EOF)
80 				;
81 			continue;
82 		}
83 		while (isspace(*p))
84 			++p;
85 		if (*p && *p != '#')
86 			break;
87 	}
88 
89 	zapchar = 0;
90 	tty.ty_name = p;
91 	p = skip(p);
92 	if (!*(tty.ty_getty = p))
93 		tty.ty_getty = tty.ty_type = NULL;
94 	else {
95 		p = skip(p);
96 		if (!*(tty.ty_type = p))
97 			tty.ty_type = NULL;
98 		else
99 			p = skip(p);
100 	}
101 	tty.ty_status = 0;
102 	tty.ty_window = NULL;
103 
104 #define	scmp(e)	!strncmp(p, e, sizeof(e) - 1) && isspace(p[sizeof(e) - 1])
105 #define	vcmp(e)	!strncmp(p, e, sizeof(e) - 1) && p[sizeof(e) - 1] == '='
106 	for (; *p; p = skip(p)) {
107 		if (scmp(_TTYS_OFF))
108 			tty.ty_status &= ~TTY_ON;
109 		else if (scmp(_TTYS_ON))
110 			tty.ty_status |= TTY_ON;
111 		else if (scmp(_TTYS_SECURE))
112 			tty.ty_status |= TTY_SECURE;
113 		else if (scmp(_TTYS_LOCAL))
114 			tty.ty_status |= TTY_LOCAL;
115 		else if (scmp(_TTYS_RTSCTS))
116 			tty.ty_status |= TTY_RTSCTS;
117 		else if (scmp(_TTYS_SOFTCAR))
118 			tty.ty_status |= TTY_SOFTCAR;
119 		else if (scmp(_TTYS_MDMBUF))
120 			tty.ty_status |= TTY_MDMBUF;
121 		else if (vcmp(_TTYS_WINDOW))
122 			tty.ty_window = value(p);
123 		else
124 			break;
125 	}
126 
127 	if (zapchar == '#' || *p == '#')
128 		while ((c = *++p) == ' ' || c == '\t')
129 			;
130 	tty.ty_comment = p;
131 	if (*p == 0)
132 		tty.ty_comment = 0;
133 	if ((p = strchr(p, '\n')))
134 		*p = '\0';
135 	return (&tty);
136 }
137 
138 #define	QUOTED	1
139 
140 /*
141  * Skip over the current field, removing quotes, and return a pointer to
142  * the next field.
143  */
144 static char *
145 skip(p)
146 	register char *p;
147 {
148 	register char *t;
149 	register int c, q;
150 
151 	for (q = 0, t = p; (c = *p) != '\0'; p++) {
152 		if (c == '"') {
153 			q ^= QUOTED;	/* obscure, but nice */
154 			continue;
155 		}
156 		if (q == QUOTED && *p == '\\' && *(p+1) == '"')
157 			p++;
158 		*t++ = *p;
159 		if (q == QUOTED)
160 			continue;
161 		if (c == '#') {
162 			zapchar = c;
163 			*p = 0;
164 			break;
165 		}
166 		if (c == '\t' || c == ' ' || c == '\n') {
167 			zapchar = c;
168 			*p++ = 0;
169 			while ((c = *p) == '\t' || c == ' ' || c == '\n')
170 				p++;
171 			break;
172 		}
173 	}
174 	*--t = '\0';
175 	return (p);
176 }
177 
178 static char *
179 value(p)
180 	register char *p;
181 {
182 
183 	return ((p = strchr(p, '=')) ? ++p : NULL);
184 }
185 
186 int
187 setttyent()
188 {
189 
190 	if (tf) {
191 		rewind(tf);
192 		return (1);
193 	} else if ((tf = fopen(_PATH_TTYS, "r")))
194 		return (1);
195 	return (0);
196 }
197 
198 int
199 endttyent()
200 {
201 	int rval;
202 
203 	if (tf) {
204 		rval = !(fclose(tf) == EOF);
205 		tf = NULL;
206 		return (rval);
207 	}
208 	return (1);
209 }
210