Update.
[glibc.git] / misc / getttyent.c
blob1bc82e6938aaa71431d24bfaa16e8c840dbac73a
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 <stdio_ext.h>
37 #include <ctype.h>
38 #include <string.h>
40 #ifdef USE_IN_LIBIO
41 # define flockfile(s) _IO_flockfile (s)
42 # define funlockfile(s) _IO_funlockfile (s)
43 #endif
45 static char zapchar;
46 static FILE *tf;
48 struct ttyent *
49 getttynam(tty)
50 const char *tty;
52 register struct ttyent *t;
54 setttyent();
55 while ((t = getttyent()))
56 if (!strcmp(tty, t->ty_name))
57 break;
58 endttyent();
59 return (t);
62 static char *skip __P((char *)) internal_function;
63 static char *value __P((char *)) internal_function;
65 struct ttyent *
66 getttyent()
68 static struct ttyent tty;
69 register int c;
70 register char *p;
71 #define MAXLINELENGTH 100
72 static char line[MAXLINELENGTH];
74 if (!tf && !setttyent())
75 return (NULL);
76 flockfile (tf);
77 for (;;) {
78 if (!fgets_unlocked(p = line, sizeof(line), tf)) {
79 funlockfile (tf);
80 return (NULL);
82 /* skip lines that are too big */
83 if (!index(p, '\n')) {
84 while ((c = getc_unlocked(tf)) != '\n' && c != EOF)
86 continue;
88 while (isspace(*p))
89 ++p;
90 if (*p && *p != '#')
91 break;
94 zapchar = 0;
95 tty.ty_name = p;
96 p = skip(p);
97 if (!*(tty.ty_getty = p))
98 tty.ty_getty = tty.ty_type = NULL;
99 else {
100 p = skip(p);
101 if (!*(tty.ty_type = p))
102 tty.ty_type = NULL;
103 else
104 p = skip(p);
106 tty.ty_status = 0;
107 tty.ty_window = NULL;
109 #define scmp(e) !strncmp(p, e, sizeof(e) - 1) && isspace(p[sizeof(e) - 1])
110 #define vcmp(e) !strncmp(p, e, sizeof(e) - 1) && p[sizeof(e) - 1] == '='
111 for (; *p; p = skip(p)) {
112 if (scmp(_TTYS_OFF))
113 tty.ty_status &= ~TTY_ON;
114 else if (scmp(_TTYS_ON))
115 tty.ty_status |= TTY_ON;
116 else if (scmp(_TTYS_SECURE))
117 tty.ty_status |= TTY_SECURE;
118 else if (vcmp(_TTYS_WINDOW))
119 tty.ty_window = value(p);
120 else
121 break;
123 /* We can release the lock only here since `zapchar' is global. */
124 funlockfile(tf);
126 if (zapchar == '#' || *p == '#')
127 while ((c = *++p) == ' ' || c == '\t')
129 tty.ty_comment = p;
130 if (*p == 0)
131 tty.ty_comment = 0;
132 if ((p = index(p, '\n')))
133 *p = '\0';
134 return (&tty);
136 libc_hidden_def (getttyent)
138 #define QUOTED 1
141 * Skip over the current field, removing quotes, and return a pointer to
142 * the next field.
144 static char *
145 internal_function
146 skip(p)
147 register char *p;
149 register char *t;
150 register int c, q;
152 for (q = 0, t = p; (c = *p) != '\0'; p++) {
153 if (c == '"') {
154 q ^= QUOTED; /* obscure, but nice */
155 continue;
157 if (q == QUOTED && *p == '\\' && *(p+1) == '"')
158 p++;
159 *t++ = *p;
160 if (q == QUOTED)
161 continue;
162 if (c == '#') {
163 zapchar = c;
164 *p = 0;
165 break;
167 if (c == '\t' || c == ' ' || c == '\n') {
168 zapchar = c;
169 *p++ = 0;
170 while ((c = *p) == '\t' || c == ' ' || c == '\n')
171 p++;
172 break;
175 *--t = '\0';
176 return (p);
179 static char *
180 internal_function
181 value(p)
182 register char *p;
185 return ((p = index(p, '=')) ? ++p : NULL);
189 setttyent()
192 if (tf) {
193 (void)rewind(tf);
194 return (1);
195 } else if ((tf = fopen(_PATH_TTYS, "r"))) {
196 /* We do the locking ourselves. */
197 __fsetlocking (tf, FSETLOCKING_BYCALLER);
198 return (1);
200 return (0);
202 libc_hidden_def (setttyent)
205 endttyent()
207 int rval;
209 if (tf) {
210 rval = !(fclose(tf) == EOF);
211 tf = NULL;
212 return (rval);
214 return (1);
216 libc_hidden_def (endttyent)