xref: /freebsd/lib/libc/gen/getttyent.c (revision 262e143bd46171a6415a5b28af260a5efa2a3db8)
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 sccsid[] = "@(#)getttyent.c	8.1 (Berkeley) 6/4/93";
36 #endif /* LIBC_SCCS and not lint */
37 #include <sys/cdefs.h>
38 __FBSDID("$FreeBSD$");
39 
40 #include <ttyent.h>
41 #include <stdio.h>
42 #include <stdlib.h>
43 #include <ctype.h>
44 #include <string.h>
45 
46 static char zapchar;
47 static FILE *tf;
48 static size_t lbsize;
49 static char *line;
50 
51 #define	MALLOCCHUNK	100
52 
53 static char *skip(char *);
54 static char *value(char *);
55 
56 struct ttyent *
57 getttynam(tty)
58 	const char *tty;
59 {
60 	struct ttyent *t;
61 
62 	if (strncmp(tty, "/dev/", 5) == 0)
63 		tty += 5;
64 	setttyent();
65 	while ( (t = getttyent()) )
66 		if (!strcmp(tty, t->ty_name))
67 			break;
68 	endttyent();
69 	return (t);
70 }
71 
72 struct ttyent *
73 getttyent()
74 {
75 	static struct ttyent tty;
76 	char *p;
77 	int c;
78 	size_t i;
79 
80 	if (!tf && !setttyent())
81 		return (NULL);
82 	for (;;) {
83 		if (!fgets(p = line, lbsize, tf))
84 			return (NULL);
85 		/* extend buffer if line was too big, and retry */
86 		while (!index(p, '\n')) {
87 			i = strlen(p);
88 			lbsize += MALLOCCHUNK;
89 			if ((p = realloc(line, lbsize)) == NULL) {
90 				(void)endttyent();
91 				return (NULL);
92 			}
93 			line = p;
94 			if (!fgets(&line[i], lbsize - i, tf))
95 				return (NULL);
96 		}
97 		while (isspace((unsigned char)*p))
98 			++p;
99 		if (*p && *p != '#')
100 			break;
101 	}
102 
103 #define scmp(e) !strncmp(p, e, sizeof(e) - 1) && isspace((unsigned char)p[sizeof(e) - 1])
104 #define	vcmp(e)	!strncmp(p, e, sizeof(e) - 1) && p[sizeof(e) - 1] == '='
105 
106 	zapchar = 0;
107 	tty.ty_name = p;
108 	tty.ty_status = 0;
109 	tty.ty_window = NULL;
110 	tty.ty_group  = _TTYS_NOGROUP;
111 
112 	p = skip(p);
113 	if (!*(tty.ty_getty = p))
114 		tty.ty_getty = tty.ty_type = NULL;
115 	else {
116 		p = skip(p);
117 		if (!*(tty.ty_type = p))
118 			tty.ty_type = NULL;
119 		else {
120 			/* compatibility kludge: handle network/dialup specially */
121 			if (scmp(_TTYS_DIALUP))
122 				tty.ty_status |= TTY_DIALUP;
123 			else if (scmp(_TTYS_NETWORK))
124 				tty.ty_status |= TTY_NETWORK;
125 			p = skip(p);
126 		}
127 	}
128 
129 	for (; *p; p = skip(p)) {
130 		if (scmp(_TTYS_OFF))
131 			tty.ty_status &= ~TTY_ON;
132 		else if (scmp(_TTYS_ON))
133 			tty.ty_status |= TTY_ON;
134 		else if (scmp(_TTYS_SECURE))
135 			tty.ty_status |= TTY_SECURE;
136 		else if (scmp(_TTYS_INSECURE))
137 			tty.ty_status &= ~TTY_SECURE;
138 		else if (scmp(_TTYS_DIALUP))
139 			tty.ty_status |= TTY_DIALUP;
140 		else if (scmp(_TTYS_NETWORK))
141 			tty.ty_status |= TTY_NETWORK;
142 		else if (vcmp(_TTYS_WINDOW))
143 			tty.ty_window = value(p);
144 		else if (vcmp(_TTYS_GROUP))
145 			tty.ty_group = value(p);
146 		else
147 			break;
148 	}
149 
150 	if (zapchar == '#' || *p == '#')
151 		while ((c = *++p) == ' ' || c == '\t')
152 			;
153 	tty.ty_comment = p;
154 	if (*p == 0)
155 		tty.ty_comment = 0;
156 	if ( (p = index(p, '\n')) )
157 		*p = '\0';
158 	return (&tty);
159 }
160 
161 #define	QUOTED	1
162 
163 /*
164  * Skip over the current field, removing quotes, and return a pointer to
165  * the next field.
166  */
167 static char *
168 skip(p)
169 	char *p;
170 {
171 	char *t;
172 	int c, q;
173 
174 	for (q = 0, t = p; (c = *p) != '\0'; p++) {
175 		if (c == '"') {
176 			q ^= QUOTED;	/* obscure, but nice */
177 			continue;
178 		}
179 		if (q == QUOTED && *p == '\\' && *(p+1) == '"')
180 			p++;
181 		*t++ = *p;
182 		if (q == QUOTED)
183 			continue;
184 		if (c == '#') {
185 			zapchar = c;
186 			*p = 0;
187 			break;
188 		}
189 		if (c == '\t' || c == ' ' || c == '\n') {
190 			zapchar = c;
191 			*p++ = 0;
192 			while ((c = *p) == '\t' || c == ' ' || c == '\n')
193 				p++;
194 			break;
195 		}
196 	}
197 	*--t = '\0';
198 	return (p);
199 }
200 
201 static char *
202 value(p)
203 	char *p;
204 {
205 
206 	return ((p = index(p, '=')) ? ++p : NULL);
207 }
208 
209 int
210 setttyent()
211 {
212 
213 	if (line == NULL) {
214 		if ((line = malloc(MALLOCCHUNK)) == NULL)
215 			return (0);
216 		lbsize = MALLOCCHUNK;
217 	}
218 	if (tf) {
219 		rewind(tf);
220 		return (1);
221 	} else if ( (tf = fopen(_PATH_TTYS, "r")) )
222 		return (1);
223 	return (0);
224 }
225 
226 int
227 endttyent()
228 {
229 	int rval;
230 
231 	/*
232          * NB: Don't free `line' because getttynam()
233 	 * may still be referencing it
234 	 */
235 	if (tf) {
236 		rval = (fclose(tf) != EOF);
237 		tf = NULL;
238 		return (rval);
239 	}
240 	return (1);
241 }
242 
243 static int
244 isttystat(tty, flag)
245 	const char *tty;
246 	int flag;
247 {
248 	struct ttyent *t;
249 
250 	return ((t = getttynam(tty)) == NULL) ? 0 : !!(t->ty_status & flag);
251 }
252 
253 
254 int
255 isdialuptty(tty)
256 	const char *tty;
257 {
258 
259 	return isttystat(tty, TTY_DIALUP);
260 }
261 
262 int isnettty(tty)
263 	const char *tty;
264 {
265 
266 	return isttystat(tty, TTY_NETWORK);
267 }
268