Update.
[glibc.git] / misc / getttyent.c
blob3295a6edac1ef19f62fed7e3ecbe33b617fc468b
1 /*
2 * Copyright (c) 1989, 1993
3 * The Regents of the University of California. All rights reserved.
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 * 4. Neither the name of the University nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
30 #if defined(LIBC_SCCS) && !defined(lint)
31 static char sccsid[] = "@(#)getttyent.c 8.1 (Berkeley) 6/4/93";
32 #endif /* LIBC_SCCS and not lint */
34 #include <ttyent.h>
35 #include <stdio.h>
36 #include <ctype.h>
37 #include <string.h>
39 #ifdef USE_IN_LIBIO
40 # define flockfile(s) _IO_flockfile (s)
41 # define funlockfile(s) _IO_funlockfile (s)
42 #endif
44 static char zapchar;
45 static FILE *tf;
47 struct ttyent *
48 getttynam(tty)
49 const char *tty;
51 register struct ttyent *t;
53 setttyent();
54 while ((t = getttyent()))
55 if (!strcmp(tty, t->ty_name))
56 break;
57 endttyent();
58 return (t);
61 static char *skip __P((char *)) internal_function;
62 static char *value __P((char *)) internal_function;
64 struct ttyent *
65 getttyent()
67 static struct ttyent tty;
68 register int c;
69 register char *p;
70 #define MAXLINELENGTH 100
71 static char line[MAXLINELENGTH];
73 if (!tf && !setttyent())
74 return (NULL);
75 flockfile (tf);
76 for (;;) {
77 if (!fgets_unlocked(p = line, sizeof(line), tf)) {
78 funlockfile (tf);
79 return (NULL);
81 /* skip lines that are too big */
82 if (!index(p, '\n')) {
83 while ((c = getc_unlocked(tf)) != '\n' && c != EOF)
85 continue;
87 while (isspace(*p))
88 ++p;
89 if (*p && *p != '#')
90 break;
93 zapchar = 0;
94 tty.ty_name = p;
95 p = skip(p);
96 if (!*(tty.ty_getty = p))
97 tty.ty_getty = tty.ty_type = NULL;
98 else {
99 p = skip(p);
100 if (!*(tty.ty_type = p))
101 tty.ty_type = NULL;
102 else
103 p = skip(p);
105 tty.ty_status = 0;
106 tty.ty_window = NULL;
108 #define scmp(e) !strncmp(p, e, sizeof(e) - 1) && isspace(p[sizeof(e) - 1])
109 #define vcmp(e) !strncmp(p, e, sizeof(e) - 1) && p[sizeof(e) - 1] == '='
110 for (; *p; p = skip(p)) {
111 if (scmp(_TTYS_OFF))
112 tty.ty_status &= ~TTY_ON;
113 else if (scmp(_TTYS_ON))
114 tty.ty_status |= TTY_ON;
115 else if (scmp(_TTYS_SECURE))
116 tty.ty_status |= TTY_SECURE;
117 else if (vcmp(_TTYS_WINDOW))
118 tty.ty_window = value(p);
119 else
120 break;
122 /* We can release the lock only here since `zapchar' is global. */
123 funlockfile(tf);
125 if (zapchar == '#' || *p == '#')
126 while ((c = *++p) == ' ' || c == '\t')
128 tty.ty_comment = p;
129 if (*p == 0)
130 tty.ty_comment = 0;
131 if ((p = index(p, '\n')))
132 *p = '\0';
133 return (&tty);
136 #define QUOTED 1
139 * Skip over the current field, removing quotes, and return a pointer to
140 * the next field.
142 static char *
143 internal_function
144 skip(p)
145 register char *p;
147 register char *t;
148 register int c, q;
150 for (q = 0, t = p; (c = *p) != '\0'; p++) {
151 if (c == '"') {
152 q ^= QUOTED; /* obscure, but nice */
153 continue;
155 if (q == QUOTED && *p == '\\' && *(p+1) == '"')
156 p++;
157 *t++ = *p;
158 if (q == QUOTED)
159 continue;
160 if (c == '#') {
161 zapchar = c;
162 *p = 0;
163 break;
165 if (c == '\t' || c == ' ' || c == '\n') {
166 zapchar = c;
167 *p++ = 0;
168 while ((c = *p) == '\t' || c == ' ' || c == '\n')
169 p++;
170 break;
173 *--t = '\0';
174 return (p);
177 static char *
178 internal_function
179 value(p)
180 register char *p;
183 return ((p = index(p, '=')) ? ++p : NULL);
187 setttyent()
190 if (tf) {
191 (void)rewind(tf);
192 return (1);
193 } else if ((tf = fopen(_PATH_TTYS, "r")))
194 return (1);
195 return (0);
199 endttyent()
201 int rval;
203 if (tf) {
204 rval = !(fclose(tf) == EOF);
205 tf = NULL;
206 return (rval);
208 return (1);