xref: /netbsd-src/lib/libc/gen/getttyent.c (revision b1c86f5f087524e68db12794ee9c3e3da1ab17a0)
1 /*	$NetBSD: getttyent.c,v 1.23 2006/04/17 23:29:21 salo 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. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 #if defined(LIBC_SCCS) && !defined(lint)
34 #if 0
35 static char sccsid[] = "@(#)getttyent.c	8.1 (Berkeley) 6/4/93";
36 #else
37 __RCSID("$NetBSD: getttyent.c,v 1.23 2006/04/17 23:29:21 salo Exp $");
38 #endif
39 #endif /* LIBC_SCCS and not lint */
40 
41 #include "namespace.h"
42 
43 #include <assert.h>
44 #include <ctype.h>
45 #include <stdio.h>
46 #include <string.h>
47 #include <ttyent.h>
48 #include <errno.h>
49 #include <err.h>
50 #include <stdlib.h>
51 
52 #ifdef __weak_alias
53 __weak_alias(endttyent,_endttyent)
54 __weak_alias(getttyent,_getttyent)
55 __weak_alias(getttynam,_getttynam)
56 __weak_alias(setttyent,_setttyent)
57 __weak_alias(setttyentpath,_setttyentpath)
58 #endif
59 
60 static FILE *tf;
61 static size_t lineno = 0;
62 static char *skip(char *, char *);
63 static char *value(char *);
64 
65 struct ttyent *
66 getttynam(const char *tty)
67 {
68 	struct ttyent *t;
69 
70 	_DIAGASSERT(tty != NULL);
71 
72 	setttyent();
73 	while ((t = getttyent()) != NULL)
74 		if (!strcmp(tty, t->ty_name))
75 			break;
76 	endttyent();
77 	return (t);
78 }
79 
80 struct ttyent *
81 getttyent(void)
82 {
83 	static struct ttyent tty;
84 	int c;
85 	char *p;
86 	size_t len;
87 	static char *line = NULL;
88 	char zapchar;
89 
90 	if (line)
91 		free(line);
92 
93 	if (!tf && !setttyent())
94 		return NULL;
95 
96 	for (;;) {
97 		errno = 0;
98 		line = fparseln(tf, &len, &lineno, NULL, FPARSELN_UNESCALL);
99 		if (line == NULL) {
100 			if (errno != 0)
101 				warn(__func__);
102 			return NULL;
103 		}
104 		for (p = line; *p && isspace((unsigned char)*p); p++)
105 			continue;
106 		if (*p && *p != '#')
107 			break;
108 		free(line);
109 	}
110 
111 	tty.ty_name = p;
112 	p = skip(p, &zapchar);
113 	if (*(tty.ty_getty = p) == '\0')
114 		tty.ty_getty = tty.ty_type = NULL;
115 	else {
116 		p = skip(p, &zapchar);
117 		if (*(tty.ty_type = p) == '\0')
118 			tty.ty_type = NULL;
119 		else
120 			p = skip(p, &zapchar);
121 	}
122 	tty.ty_status = 0;
123 	tty.ty_window = NULL;
124 	tty.ty_class = NULL;
125 
126 #define	scmp(e)	!strncmp(p, e, sizeof(e) - 1) && (isspace((unsigned char) p[sizeof(e) - 1]) || p[sizeof(e) - 1] == '\0')
127 #define	vcmp(e)	!strncmp(p, e, sizeof(e) - 1) && p[sizeof(e) - 1] == '='
128 	for (; *p; p = skip(p, &zapchar)) {
129 		if (scmp(_TTYS_OFF))
130 			tty.ty_status &= ~TTY_ON;
131 		else if (scmp(_TTYS_ON))
132 			tty.ty_status |= TTY_ON;
133 		else if (scmp(_TTYS_SECURE))
134 			tty.ty_status |= TTY_SECURE;
135 		else if (scmp(_TTYS_LOCAL))
136 			tty.ty_status |= TTY_LOCAL;
137 		else if (scmp(_TTYS_RTSCTS))
138 			tty.ty_status |= TTY_RTSCTS;
139 		else if (scmp(_TTYS_DTRCTS))
140 			tty.ty_status |= TTY_DTRCTS;
141 		else if (scmp(_TTYS_SOFTCAR))
142 			tty.ty_status |= TTY_SOFTCAR;
143 		else if (scmp(_TTYS_MDMBUF))
144 			tty.ty_status |= TTY_MDMBUF;
145 		else if (vcmp(_TTYS_WINDOW))
146 			tty.ty_window = value(p);
147 		else if (vcmp(_TTYS_CLASS))
148 			tty.ty_class = value(p);
149 		else
150 			warnx("%s: %s, %lu: unknown option `%s'",
151 			    __func__, _PATH_TTYS, (unsigned long)lineno, p);
152 	}
153 
154 	if (zapchar == '#' || *p == '#')
155 		while ((c = *++p) == ' ' || c == '\t')
156 			continue;
157 	tty.ty_comment = p;
158 	if (*p == '\0')
159 		tty.ty_comment = NULL;
160 	if ((p = strchr(p, '\n')) != NULL)
161 		*p = '\0';
162 	return &tty;
163 }
164 
165 #define	QUOTED	1
166 
167 /*
168  * Skip over the current field, removing quotes, and return a pointer to
169  * the next field.
170  */
171 static char *
172 skip(char *p, char *zapchar)
173 {
174 	char *t;
175 	int c, q;
176 
177 	_DIAGASSERT(p != NULL);
178 	*zapchar = '\0';
179 
180 	for (q = 0, t = p; (c = *p) != '\0'; p++) {
181 		if (c == '"') {
182 			q ^= QUOTED;	/* obscure, but nice */
183 			continue;
184 		}
185 		if (q == QUOTED && *p == '\\' && *(p+1) == '"')
186 			p++;
187 		*t++ = *p;
188 		if (q == QUOTED)
189 			continue;
190 		if (c == '#') {
191 			*zapchar = c;
192 			*p = '\0';
193 			*--t = '\0';
194 			return p;
195 		}
196 		if (c == '\t' || c == ' ' || c == '\n') {
197 			*zapchar = c;
198 			*p++ = '\0';
199 			while ((c = *p) == '\t' || c == ' ' || c == '\n')
200 				p++;
201 			*--t = '\0';
202 			return p;
203 		}
204 	}
205 	if (t != p)
206 		*t = '\0';
207 	return p;
208 }
209 
210 static char *
211 value(char *p)
212 {
213 
214 	_DIAGASSERT(p != NULL);
215 
216 	return (p = strchr(p, '=')) != NULL ? ++p : NULL;
217 }
218 
219 int
220 setttyentpath(const char *path)
221 {
222 	lineno = 0;
223 	if (tf) {
224 		rewind(tf);
225 		return 1;
226 	} else if ((tf = fopen(path, "r")) != NULL)
227 		return 1;
228 	return 0;
229 }
230 
231 int
232 setttyent(void)
233 {
234 	return setttyentpath(_PATH_TTYS);
235 }
236 
237 int
238 endttyent(void)
239 {
240 	int rval;
241 
242 	if (tf) {
243 		rval = !(fclose(tf) == EOF);
244 		tf = NULL;
245 		return rval;
246 	}
247 	return 1;
248 }
249