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 * 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.
16 *
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.
28 */
29
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 */
33
34 #include <ttyent.h>
35 #include <stdio.h>
36 #include <stdio_ext.h>
37 #include <ctype.h>
38 #include <string.h>
39
40 #define flockfile(s) _IO_flockfile (s)
41 #define funlockfile(s) _IO_funlockfile (s)
42
43 static char zapchar;
44 static FILE *tf;
45
46 struct ttyent *
47 __getttynam (const char *tty)
48 {
49 struct ttyent *t;
50
51 __setttyent();
52 while ((t = __getttyent()))
53 if (!strcmp(tty, t->ty_name))
54 break;
55 __endttyent();
56 return (t);
57 }
58 weak_alias (__getttynam, getttynam)
59
60 static char *skip (char *) __THROW;
61 static char *value (char *) __THROW;
62
63 struct ttyent *
64 __getttyent (void)
65 {
66 static struct ttyent tty;
67 int c;
68 char *p;
69 #define MAXLINELENGTH 100
70 static char line[MAXLINELENGTH];
71
72 if (!tf && !__setttyent())
73 return (NULL);
74 flockfile (tf);
75 for (;;) {
76 if (!__fgets_unlocked(p = line, sizeof(line), tf)) {
77 funlockfile (tf);
78 return (NULL);
79 }
80 /* skip lines that are too big */
81 if (!strchr (p, '\n')) {
82 while ((c = __getc_unlocked(tf)) != '\n' && c != EOF)
83 ;
84 continue;
85 }
86 while (isspace(*p))
87 ++p;
88 if (*p && *p != '#')
89 break;
90 }
91
92 zapchar = 0;
93 tty.ty_name = p;
94 p = skip(p);
95 if (!*(tty.ty_getty = p))
96 tty.ty_getty = tty.ty_type = NULL;
97 else {
98 p = skip(p);
99 if (!*(tty.ty_type = p))
100 tty.ty_type = NULL;
101 else
102 p = skip(p);
103 }
104 tty.ty_status = 0;
105 tty.ty_window = NULL;
106
107 #define scmp(e) !strncmp(p, e, sizeof(e) - 1) && isspace(p[sizeof(e) - 1])
108 #define vcmp(e) !strncmp(p, e, sizeof(e) - 1) && p[sizeof(e) - 1] == '='
109 for (; *p; p = skip(p)) {
110 if (scmp(_TTYS_OFF))
111 tty.ty_status &= ~TTY_ON;
112 else if (scmp(_TTYS_ON))
113 tty.ty_status |= TTY_ON;
114 else if (scmp(_TTYS_SECURE))
115 tty.ty_status |= TTY_SECURE;
116 else if (vcmp(_TTYS_WINDOW))
117 tty.ty_window = value(p);
118 else
119 break;
120 }
121 /* We can release the lock only here since `zapchar' is global. */
122 funlockfile(tf);
123
124 if (zapchar == '#' || *p == '#')
125 while ((c = *++p) == ' ' || c == '\t')
126 ;
127 tty.ty_comment = p;
128 if (*p == 0)
129 tty.ty_comment = 0;
130 if ((p = strchr (p, '\n')))
131 *p = '\0';
132 return (&tty);
133 }
134 libc_hidden_def (__getttyent)
135 weak_alias (__getttyent, getttyent)
136
137 #define QUOTED 1
138
139 /*
140 * Skip over the current field, removing quotes, and return a pointer to
141 * the next field.
142 */
143 static char *
144 skip (char *p)
145 {
146 char *t;
147 int c, q;
148
149 for (q = 0, t = p; (c = *p) != '\0'; p++) {
150 if (c == '"') {
151 q ^= QUOTED; /* obscure, but nice */
152 continue;
153 }
154 if (q == QUOTED && *p == '\\' && *(p+1) == '"')
155 p++;
156 *t++ = *p;
157 if (q == QUOTED)
158 continue;
159 if (c == '#') {
160 zapchar = c;
161 *p = 0;
162 break;
163 }
164 if (c == '\t' || c == ' ' || c == '\n') {
165 zapchar = c;
166 *p++ = 0;
167 while ((c = *p) == '\t' || c == ' ' || c == '\n')
168 p++;
169 break;
170 }
171 }
172 *--t = '\0';
173 return (p);
174 }
175
176 static char *
177 value (char *p)
178 {
179
180 return ((p = strchr (p, '=')) ? ++p : NULL);
181 }
182
183 int
184 __setttyent (void)
185 {
186
187 if (tf) {
188 (void)rewind(tf);
189 return (1);
190 } else if ((tf = fopen(_PATH_TTYS, "rce"))) {
191 /* We do the locking ourselves. */
192 __fsetlocking (tf, FSETLOCKING_BYCALLER);
193 return (1);
194 }
195 return (0);
196 }
197 libc_hidden_def (__setttyent)
198 weak_alias (__setttyent, setttyent)
199
200 int
201 __endttyent (void)
202 {
203 int rval;
204
205 if (tf) {
206 rval = !(fclose(tf) == EOF);
207 tf = NULL;
208 return (rval);
209 }
210 return (1);
211 }
212 libc_hidden_def (__endttyent)
213 weak_alias (__endttyent, endttyent)