xref: /freebsd/stand/common/console.c (revision 5596f836e7e04a272113e57b3a80f1f67c0fec7f)
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,
58 	    env_nounset);
59 
60 	/* Do all console probes */
61 	for (cons = 0; consoles[cons] != NULL; cons++) {
62 		consoles[cons]->c_flags = 0;
63 		consoles[cons]->c_probe(consoles[cons]);
64 	}
65 	/* Now find the first working one */
66 	active = -1;
67 	for (cons = 0; consoles[cons] != NULL && active == -1; cons++) {
68 		consoles[cons]->c_flags = 0;
69 		consoles[cons]->c_probe(consoles[cons]);
70 		if (consoles[cons]->c_flags == (C_PRESENTIN | C_PRESENTOUT))
71 			active = cons;
72 	}
73 	/* Force a console even if all probes failed */
74 	if (active == -1)
75 		active = 0;
76 
77 	/* Check to see if a console preference has already been registered */
78 	prefconsole = getenv("console");
79 	if (prefconsole != NULL)
80 		prefconsole = strdup(prefconsole);
81 	if (prefconsole != NULL) {
82 		unsetenv("console");		/* we want to replace this */
83 		cons_change(prefconsole);
84 	} else {
85 		consoles[active]->c_flags |= C_ACTIVEIN | C_ACTIVEOUT;
86 		consoles[active]->c_init(0);
87 		prefconsole = strdup(consoles[active]->c_name);
88 	}
89 
90 	printf("Consoles: ");
91 	for (cons = 0; consoles[cons] != NULL; cons++)
92 		if (consoles[cons]->c_flags & (C_ACTIVEIN | C_ACTIVEOUT))
93 			printf("%s  ", consoles[cons]->c_desc);
94 	printf("\n");
95 
96 	if (prefconsole != NULL) {
97 		env_setenv("console", EV_VOLATILE, prefconsole, cons_set,
98 		    env_nounset);
99 		free(prefconsole);
100 	}
101 }
102 
103 int
104 getchar(void)
105 {
106 	int	cons;
107 	int	rv;
108 
109 	/* Loop forever polling all active consoles */
110 	for (;;) {
111 		for (cons = 0; consoles[cons] != NULL; cons++) {
112 			if ((consoles[cons]->c_flags &
113 			    (C_PRESENTIN | C_ACTIVEIN)) ==
114 			    (C_PRESENTIN | C_ACTIVEIN) &&
115 			    ((rv = consoles[cons]->c_in()) != -1))
116 				return (rv);
117 		}
118 	}
119 }
120 
121 int
122 ischar(void)
123 {
124 	int	cons;
125 
126 	for (cons = 0; consoles[cons] != NULL; cons++)
127 		if ((consoles[cons]->c_flags & (C_PRESENTIN | C_ACTIVEIN)) ==
128 		    (C_PRESENTIN | C_ACTIVEIN) &&
129 		    (consoles[cons]->c_ready() != 0))
130 			return (1);
131 	return (0);
132 }
133 
134 void
135 putchar(int c)
136 {
137 	int	cons;
138 
139 	/* Expand newlines */
140 	if (c == '\n')
141 		putchar('\r');
142 
143 	for (cons = 0; consoles[cons] != NULL; cons++) {
144 		if ((consoles[cons]->c_flags & (C_PRESENTOUT | C_ACTIVEOUT)) ==
145 		    (C_PRESENTOUT | C_ACTIVEOUT))
146 			consoles[cons]->c_out(c);
147 	}
148 }
149 
150 /*
151  * Find the console with the specified name.
152  */
153 static int
154 cons_find(const char *name)
155 {
156 	int	cons;
157 
158 	for (cons = 0; consoles[cons] != NULL; cons++)
159 		if (strcmp(consoles[cons]->c_name, name) == 0)
160 			return (cons);
161 	return (-1);
162 }
163 
164 /*
165  * Select one or more consoles.
166  */
167 static int
168 cons_set(struct env_var *ev, int flags, const void *value)
169 {
170 	int	ret;
171 
172 	if ((value == NULL) || (cons_check(value) == 0)) {
173 		/*
174 		 * Return CMD_OK instead of CMD_ERROR to prevent forth syntax
175 		 * error, which would prevent it processing any further
176 		 * loader.conf entries.
177 		 */
178 		return (CMD_OK);
179 	}
180 
181 	ret = cons_change(value);
182 	if (ret != CMD_OK)
183 		return (ret);
184 
185 	env_setenv(ev->ev_name, flags | EV_NOHOOK, value, NULL, NULL);
186 	return (CMD_OK);
187 }
188 
189 /*
190  * Check that at least one the consoles listed in *string is valid
191  */
192 static int
193 cons_check(const char *string)
194 {
195 	int	cons, found, failed;
196 	char	*curpos, *dup, *next;
197 
198 	dup = next = strdup(string);
199 	found = failed = 0;
200 	while (next != NULL) {
201 		curpos = strsep(&next, " ,");
202 		if (*curpos != '\0') {
203 			cons = cons_find(curpos);
204 			if (cons == -1) {
205 				printf("console %s is invalid!\n", curpos);
206 				failed++;
207 			} else {
208 				found++;
209 			}
210 		}
211 	}
212 
213 	free(dup);
214 
215 	if (found == 0)
216 		printf("no valid consoles!\n");
217 
218 	if (found == 0 || failed != 0) {
219 		printf("Available consoles:\n");
220 		for (cons = 0; consoles[cons] != NULL; cons++)
221 			printf("    %s\n", consoles[cons]->c_name);
222 	}
223 
224 	return (found);
225 }
226 
227 /*
228  * Activate all the valid consoles listed in *string and disable all others.
229  */
230 static int
231 cons_change(const char *string)
232 {
233 	int	cons, active;
234 	char	*curpos, *dup, *next;
235 
236 	/* Disable all consoles */
237 	for (cons = 0; consoles[cons] != NULL; cons++) {
238 		consoles[cons]->c_flags &= ~(C_ACTIVEIN | C_ACTIVEOUT);
239 	}
240 
241 	/* Enable selected consoles */
242 	dup = next = strdup(string);
243 	active = 0;
244 	while (next != NULL) {
245 		curpos = strsep(&next, " ,");
246 		if (*curpos == '\0')
247 			continue;
248 		cons = cons_find(curpos);
249 		if (cons >= 0) {
250 			consoles[cons]->c_flags |= C_ACTIVEIN | C_ACTIVEOUT;
251 			consoles[cons]->c_init(0);
252 			if ((consoles[cons]->c_flags &
253 			    (C_PRESENTIN | C_PRESENTOUT)) ==
254 			    (C_PRESENTIN | C_PRESENTOUT)) {
255 				active++;
256 				continue;
257 			}
258 
259 			if (active != 0) {
260 				/*
261 				 * If no consoles have initialised we
262 				 * wouldn't see this.
263 				 */
264 				printf("console %s failed to initialize\n",
265 				    consoles[cons]->c_name);
266 			}
267 		}
268 	}
269 
270 	free(dup);
271 
272 	if (active == 0) {
273 		/*
274 		 * All requested consoles failed to initialise,
275 		 * try to recover.
276 		 */
277 		for (cons = 0; consoles[cons] != NULL; cons++) {
278 			consoles[cons]->c_flags |= C_ACTIVEIN | C_ACTIVEOUT;
279 			consoles[cons]->c_init(0);
280 			if ((consoles[cons]->c_flags &
281 			    (C_PRESENTIN | C_PRESENTOUT)) ==
282 			    (C_PRESENTIN | C_PRESENTOUT))
283 				active++;
284 		}
285 
286 		if (active == 0)
287 			return (CMD_ERROR); /* Recovery failed. */
288 	}
289 
290 	return (CMD_OK);
291 }
292 
293 /*
294  * Change the twiddle divisor.
295  *
296  * The user can set the twiddle_divisor variable to directly control how fast
297  * the progress twiddle spins, useful for folks with slow serial consoles.  The
298  * code to monitor changes to the variable and propagate them to the twiddle
299  * routines has to live somewhere.  Twiddling is console-related so it's here.
300  */
301 static int
302 twiddle_set(struct env_var *ev, int flags, const void *value)
303 {
304 	u_long tdiv;
305 	char *eptr;
306 
307 	tdiv = strtoul(value, &eptr, 0);
308 	if (*(const char *)value == 0 || *eptr != 0) {
309 		printf("invalid twiddle_divisor '%s'\n", (const char *)value);
310 		return (CMD_ERROR);
311 	}
312 	twiddle_divisor((u_int)tdiv);
313 	env_setenv(ev->ev_name, flags | EV_NOHOOK, value, NULL, NULL);
314 
315 	return (CMD_OK);
316 }
317