xref: /freebsd/stand/common/console.c (revision 7cd22ac43418da08448d0bab1009ff3cbda85120)
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 	TSENTER();
57 
58 	/* We want a callback to install the new value when this var changes. */
59 	env_setenv("twiddle_divisor", EV_VOLATILE, "1", twiddle_set,
60 	    env_nounset);
61 
62 	/* Do all console probes */
63 	for (cons = 0; consoles[cons] != NULL; cons++) {
64 		consoles[cons]->c_flags = 0;
65 		consoles[cons]->c_probe(consoles[cons]);
66 	}
67 	/* Now find the first working one */
68 	active = -1;
69 	for (cons = 0; consoles[cons] != NULL && active == -1; cons++) {
70 		consoles[cons]->c_flags = 0;
71 		consoles[cons]->c_probe(consoles[cons]);
72 		if (consoles[cons]->c_flags == (C_PRESENTIN | C_PRESENTOUT))
73 			active = cons;
74 	}
75 	/* Force a console even if all probes failed */
76 	if (active == -1)
77 		active = 0;
78 
79 	/* Check to see if a console preference has already been registered */
80 	prefconsole = getenv("console");
81 	if (prefconsole != NULL)
82 		prefconsole = strdup(prefconsole);
83 	if (prefconsole != NULL) {
84 		unsetenv("console");		/* we want to replace this */
85 		cons_change(prefconsole);
86 	} else {
87 		consoles[active]->c_flags |= C_ACTIVEIN | C_ACTIVEOUT;
88 		consoles[active]->c_init(0);
89 		prefconsole = strdup(consoles[active]->c_name);
90 	}
91 
92 	printf("Consoles: ");
93 	for (cons = 0; consoles[cons] != NULL; cons++)
94 		if (consoles[cons]->c_flags & (C_ACTIVEIN | C_ACTIVEOUT))
95 			printf("%s  ", consoles[cons]->c_desc);
96 	printf("\n");
97 
98 	if (prefconsole != NULL) {
99 		env_setenv("console", EV_VOLATILE, prefconsole, cons_set,
100 		    env_nounset);
101 		free(prefconsole);
102 	}
103 
104 	TSEXIT();
105 }
106 
107 int
108 getchar(void)
109 {
110 	int	cons;
111 	int	rv;
112 
113 	/* Loop forever polling all active consoles */
114 	for (;;) {
115 		for (cons = 0; consoles[cons] != NULL; cons++) {
116 			if ((consoles[cons]->c_flags &
117 			    (C_PRESENTIN | C_ACTIVEIN)) ==
118 			    (C_PRESENTIN | C_ACTIVEIN) &&
119 			    ((rv = consoles[cons]->c_in()) != -1))
120 				return (rv);
121 		}
122 	}
123 }
124 
125 int
126 ischar(void)
127 {
128 	int	cons;
129 
130 	for (cons = 0; consoles[cons] != NULL; cons++)
131 		if ((consoles[cons]->c_flags & (C_PRESENTIN | C_ACTIVEIN)) ==
132 		    (C_PRESENTIN | C_ACTIVEIN) &&
133 		    (consoles[cons]->c_ready() != 0))
134 			return (1);
135 	return (0);
136 }
137 
138 void
139 putchar(int c)
140 {
141 	int	cons;
142 
143 	/* Expand newlines */
144 	if (c == '\n')
145 		putchar('\r');
146 
147 	for (cons = 0; consoles[cons] != NULL; cons++) {
148 		if ((consoles[cons]->c_flags & (C_PRESENTOUT | C_ACTIVEOUT)) ==
149 		    (C_PRESENTOUT | C_ACTIVEOUT))
150 			consoles[cons]->c_out(c);
151 	}
152 }
153 
154 /*
155  * Find the console with the specified name.
156  */
157 static int
158 cons_find(const char *name)
159 {
160 	int	cons;
161 
162 	for (cons = 0; consoles[cons] != NULL; cons++)
163 		if (strcmp(consoles[cons]->c_name, name) == 0)
164 			return (cons);
165 	return (-1);
166 }
167 
168 /*
169  * Select one or more consoles.
170  */
171 static int
172 cons_set(struct env_var *ev, int flags, const void *value)
173 {
174 	int	ret;
175 
176 	if ((value == NULL) || (cons_check(value) == 0)) {
177 		/*
178 		 * Return CMD_OK instead of CMD_ERROR to prevent forth syntax
179 		 * error, which would prevent it processing any further
180 		 * loader.conf entries.
181 		 */
182 		return (CMD_OK);
183 	}
184 
185 	ret = cons_change(value);
186 	if (ret != CMD_OK)
187 		return (ret);
188 
189 	env_setenv(ev->ev_name, flags | EV_NOHOOK, value, NULL, NULL);
190 	return (CMD_OK);
191 }
192 
193 /*
194  * Check that at least one the consoles listed in *string is valid
195  */
196 static int
197 cons_check(const char *string)
198 {
199 	int	cons, found, failed;
200 	char	*curpos, *dup, *next;
201 
202 	dup = next = strdup(string);
203 	found = failed = 0;
204 	while (next != NULL) {
205 		curpos = strsep(&next, " ,");
206 		if (*curpos != '\0') {
207 			cons = cons_find(curpos);
208 			if (cons == -1) {
209 				printf("console %s is invalid!\n", curpos);
210 				failed++;
211 			} else {
212 				found++;
213 			}
214 		}
215 	}
216 
217 	free(dup);
218 
219 	if (found == 0)
220 		printf("no valid consoles!\n");
221 
222 	if (found == 0 || failed != 0) {
223 		printf("Available consoles:\n");
224 		for (cons = 0; consoles[cons] != NULL; cons++)
225 			printf("    %s\n", consoles[cons]->c_name);
226 	}
227 
228 	return (found);
229 }
230 
231 /*
232  * Activate all the valid consoles listed in *string and disable all others.
233  */
234 static int
235 cons_change(const char *string)
236 {
237 	int	cons, active;
238 	char	*curpos, *dup, *next;
239 
240 	/* Disable all consoles */
241 	for (cons = 0; consoles[cons] != NULL; cons++) {
242 		consoles[cons]->c_flags &= ~(C_ACTIVEIN | C_ACTIVEOUT);
243 	}
244 
245 	/* Enable selected consoles */
246 	dup = next = strdup(string);
247 	active = 0;
248 	while (next != NULL) {
249 		curpos = strsep(&next, " ,");
250 		if (*curpos == '\0')
251 			continue;
252 		cons = cons_find(curpos);
253 		if (cons >= 0) {
254 			consoles[cons]->c_flags |= C_ACTIVEIN | C_ACTIVEOUT;
255 			consoles[cons]->c_init(0);
256 			if ((consoles[cons]->c_flags &
257 			    (C_PRESENTIN | C_PRESENTOUT)) ==
258 			    (C_PRESENTIN | C_PRESENTOUT)) {
259 				active++;
260 				continue;
261 			}
262 
263 			if (active != 0) {
264 				/*
265 				 * If no consoles have initialised we
266 				 * wouldn't see this.
267 				 */
268 				printf("console %s failed to initialize\n",
269 				    consoles[cons]->c_name);
270 			}
271 		}
272 	}
273 
274 	free(dup);
275 
276 	if (active == 0) {
277 		/*
278 		 * All requested consoles failed to initialise,
279 		 * try to recover.
280 		 */
281 		for (cons = 0; consoles[cons] != NULL; cons++) {
282 			consoles[cons]->c_flags |= C_ACTIVEIN | C_ACTIVEOUT;
283 			consoles[cons]->c_init(0);
284 			if ((consoles[cons]->c_flags &
285 			    (C_PRESENTIN | C_PRESENTOUT)) ==
286 			    (C_PRESENTIN | C_PRESENTOUT))
287 				active++;
288 		}
289 
290 		if (active == 0)
291 			return (CMD_ERROR); /* Recovery failed. */
292 	}
293 
294 	return (CMD_OK);
295 }
296 
297 /*
298  * Change the twiddle divisor.
299  *
300  * The user can set the twiddle_divisor variable to directly control how fast
301  * the progress twiddle spins, useful for folks with slow serial consoles.  The
302  * code to monitor changes to the variable and propagate them to the twiddle
303  * routines has to live somewhere.  Twiddling is console-related so it's here.
304  */
305 static int
306 twiddle_set(struct env_var *ev, int flags, const void *value)
307 {
308 	u_long tdiv;
309 	char *eptr;
310 
311 	tdiv = strtoul(value, &eptr, 0);
312 	if (*(const char *)value == 0 || *eptr != 0) {
313 		printf("invalid twiddle_divisor '%s'\n", (const char *)value);
314 		return (CMD_ERROR);
315 	}
316 	twiddle_divisor((u_int)tdiv);
317 	env_setenv(ev->ev_name, flags | EV_NOHOOK, value, NULL, NULL);
318 
319 	return (CMD_OK);
320 }
321