xref: /freebsd/stand/common/console.c (revision 389e4940069316fe667ffa263fa7d6390d0a960f)
1 /*-
2  * Copyright (c) 1998 Michael Smith <msmith@freebsd.org>
3  * 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  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include <stand.h>
31 #include <string.h>
32 
33 #include "bootstrap.h"
34 /*
35  * Core console support
36  */
37 
38 static int	cons_set(struct env_var *ev, int flags, const void *value);
39 static int	cons_find(const char *name);
40 static int	cons_check(const char *string);
41 static int	cons_change(const char *string);
42 static int	twiddle_set(struct env_var *ev, int flags, const void *value);
43 
44 /*
45  * Detect possible console(s) to use.  If preferred console(s) have been
46  * specified, mark them as active. Else, mark the first probed console
47  * as active.  Also create the console variable.
48  */
49 void
50 cons_probe(void)
51 {
52     int			cons;
53     int			active;
54     char		*prefconsole;
55 
56     /* We want a callback to install the new value when this var changes. */
57     env_setenv("twiddle_divisor", EV_VOLATILE, "1", twiddle_set, env_nounset);
58 
59     /* Do all console probes */
60     for (cons = 0; consoles[cons] != NULL; cons++) {
61 	consoles[cons]->c_flags = 0;
62  	consoles[cons]->c_probe(consoles[cons]);
63     }
64     /* Now find the first working one */
65     active = -1;
66     for (cons = 0; consoles[cons] != NULL && active == -1; cons++) {
67 	consoles[cons]->c_flags = 0;
68  	consoles[cons]->c_probe(consoles[cons]);
69 	if (consoles[cons]->c_flags == (C_PRESENTIN | C_PRESENTOUT))
70 	    active = cons;
71     }
72     /* Force a console even if all probes failed */
73     if (active == -1)
74 	active = 0;
75 
76     /* Check to see if a console preference has already been registered */
77     prefconsole = getenv("console");
78     if (prefconsole != NULL)
79 	prefconsole = strdup(prefconsole);
80     if (prefconsole != NULL) {
81 	unsetenv("console");		/* we want to replace this */
82 	cons_change(prefconsole);
83     } else {
84 	consoles[active]->c_flags |= C_ACTIVEIN | C_ACTIVEOUT;
85 	consoles[active]->c_init(0);
86 	prefconsole = strdup(consoles[active]->c_name);
87     }
88 
89     printf("Consoles: ");
90     for (cons = 0; consoles[cons] != NULL; cons++)
91 	if (consoles[cons]->c_flags & (C_ACTIVEIN | C_ACTIVEOUT))
92 	    printf("%s  ", consoles[cons]->c_desc);
93     printf("\n");
94 
95     if (prefconsole != NULL) {
96 	env_setenv("console", EV_VOLATILE, prefconsole, cons_set,
97 	    env_nounset);
98 	free(prefconsole);
99     }
100 }
101 
102 int
103 getchar(void)
104 {
105     int		cons;
106     int		rv;
107 
108     /* Loop forever polling all active consoles */
109     for(;;)
110 	for (cons = 0; consoles[cons] != NULL; cons++)
111 	    if ((consoles[cons]->c_flags & (C_PRESENTIN | C_ACTIVEIN)) ==
112 		(C_PRESENTIN | C_ACTIVEIN) &&
113 		((rv = consoles[cons]->c_in()) != -1))
114 		return(rv);
115 }
116 
117 int
118 ischar(void)
119 {
120     int		cons;
121 
122     for (cons = 0; consoles[cons] != NULL; cons++)
123 	if ((consoles[cons]->c_flags & (C_PRESENTIN | C_ACTIVEIN)) ==
124 	    (C_PRESENTIN | C_ACTIVEIN) &&
125 	    (consoles[cons]->c_ready() != 0))
126 		return(1);
127     return(0);
128 }
129 
130 void
131 putchar(int c)
132 {
133     int		cons;
134 
135     /* Expand newlines */
136     if (c == '\n')
137 	putchar('\r');
138 
139     for (cons = 0; consoles[cons] != NULL; cons++)
140 	if ((consoles[cons]->c_flags & (C_PRESENTOUT | C_ACTIVEOUT)) ==
141 	    (C_PRESENTOUT | C_ACTIVEOUT))
142 	    consoles[cons]->c_out(c);
143 }
144 
145 /*
146  * Find the console with the specified name.
147  */
148 static int
149 cons_find(const char *name)
150 {
151     int		cons;
152 
153     for (cons = 0; consoles[cons] != NULL; cons++)
154 	if (!strcmp(consoles[cons]->c_name, name))
155 	    return (cons);
156     return (-1);
157 }
158 
159 /*
160  * Select one or more consoles.
161  */
162 static int
163 cons_set(struct env_var *ev, int flags, const void *value)
164 {
165     int		ret;
166 
167     if ((value == NULL) || (cons_check(value) == 0)) {
168 	/*
169 	 * Return CMD_OK instead of CMD_ERROR to prevent forth syntax error,
170 	 * which would prevent it processing any further loader.conf entries.
171 	 */
172 	return (CMD_OK);
173     }
174 
175     ret = cons_change(value);
176     if (ret != CMD_OK)
177 	return (ret);
178 
179     env_setenv(ev->ev_name, flags | EV_NOHOOK, value, NULL, NULL);
180     return (CMD_OK);
181 }
182 
183 /*
184  * Check that at least one the consoles listed in *string is valid
185  */
186 static int
187 cons_check(const char *string)
188 {
189     int		cons, found, failed;
190     char	*curpos, *dup, *next;
191 
192     dup = next = strdup(string);
193     found = failed = 0;
194     while (next != NULL) {
195 	curpos = strsep(&next, " ,");
196 	if (*curpos != '\0') {
197 	    cons = cons_find(curpos);
198 	    if (cons == -1) {
199 		printf("console %s is invalid!\n", curpos);
200 		failed++;
201 	    } else {
202 		found++;
203 	    }
204 	}
205     }
206 
207     free(dup);
208 
209     if (found == 0)
210 	printf("no valid consoles!\n");
211 
212     if (found == 0 || failed != 0) {
213 	printf("Available consoles:\n");
214 	for (cons = 0; consoles[cons] != NULL; cons++)
215 	    printf("    %s\n", consoles[cons]->c_name);
216     }
217 
218     return (found);
219 }
220 
221 /*
222  * Activate all the valid consoles listed in *string and disable all others.
223  */
224 static int
225 cons_change(const char *string)
226 {
227     int		cons, active;
228     char	*curpos, *dup, *next;
229 
230     /* Disable all consoles */
231     for (cons = 0; consoles[cons] != NULL; cons++) {
232 	consoles[cons]->c_flags &= ~(C_ACTIVEIN | C_ACTIVEOUT);
233     }
234 
235     /* Enable selected consoles */
236     dup = next = strdup(string);
237     active = 0;
238     while (next != NULL) {
239 	curpos = strsep(&next, " ,");
240 	if (*curpos == '\0')
241 		continue;
242 	cons = cons_find(curpos);
243 	if (cons >= 0) {
244 	    consoles[cons]->c_flags |= C_ACTIVEIN | C_ACTIVEOUT;
245 	    consoles[cons]->c_init(0);
246 	    if ((consoles[cons]->c_flags & (C_PRESENTIN | C_PRESENTOUT)) ==
247 		(C_PRESENTIN | C_PRESENTOUT)) {
248 		active++;
249 		continue;
250 	    }
251 
252 	    if (active != 0) {
253 		/* If no consoles have initialised we wouldn't see this. */
254 		printf("console %s failed to initialize\n", consoles[cons]->c_name);
255 	    }
256 	}
257     }
258 
259     free(dup);
260 
261     if (active == 0) {
262 	/* All requested consoles failed to initialise, try to recover. */
263 	for (cons = 0; consoles[cons] != NULL; cons++) {
264 	    consoles[cons]->c_flags |= C_ACTIVEIN | C_ACTIVEOUT;
265 	    consoles[cons]->c_init(0);
266 	    if ((consoles[cons]->c_flags &
267 		(C_PRESENTIN | C_PRESENTOUT)) ==
268 		(C_PRESENTIN | C_PRESENTOUT))
269 		active++;
270 	}
271 
272 	if (active == 0)
273 	    return (CMD_ERROR); /* Recovery failed. */
274     }
275 
276     return (CMD_OK);
277 }
278 
279 /*
280  * Change the twiddle divisor.
281  *
282  * The user can set the twiddle_divisor variable to directly control how fast
283  * the progress twiddle spins, useful for folks with slow serial consoles.  The
284  * code to monitor changes to the variable and propagate them to the twiddle
285  * routines has to live somewhere.  Twiddling is console-related so it's here.
286  */
287 static int
288 twiddle_set(struct env_var *ev, int flags, const void *value)
289 {
290     u_long tdiv;
291     char * eptr;
292 
293     tdiv = strtoul(value, &eptr, 0);
294     if (*(const char *)value == 0 || *eptr != 0) {
295 	printf("invalid twiddle_divisor '%s'\n", (const char *)value);
296 	return (CMD_ERROR);
297     }
298     twiddle_divisor((u_int)tdiv);
299     env_setenv(ev->ev_name, flags | EV_NOHOOK, value, NULL, NULL);
300 
301     return(CMD_OK);
302 }
303