FreeBSD/Linux Kernel Cross Reference
sys/boot/common/boot.c
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 /*
31 * Loading modules, booting the system
32 */
33
34 #include <stand.h>
35 #include <string.h>
36
37 #include "bootstrap.h"
38
39 static char *getbootfile(int try);
40 static int loadakernel(int try, int argc, char* argv[]);
41
42 /* List of kernel names to try (may be overwritten by boot.config) XXX should move from here? */
43 static const char *default_bootfiles = "kernel";
44
45 static int autoboot_tried;
46
47 /*
48 * The user wants us to boot.
49 */
50 COMMAND_SET(boot, "boot", "boot a file or loaded kernel", command_boot);
51
52 static int
53 command_boot(int argc, char *argv[])
54 {
55 struct preloaded_file *fp;
56
57 /*
58 * See if the user has specified an explicit kernel to boot.
59 */
60 if ((argc > 1) && (argv[1][0] != '-')) {
61
62 /* XXX maybe we should discard everything and start again? */
63 if (file_findfile(NULL, NULL) != NULL) {
64 sprintf(command_errbuf, "can't boot '%s', kernel module already loaded", argv[1]);
65 return(CMD_ERROR);
66 }
67
68 /* find/load the kernel module */
69 if (mod_loadkld(argv[1], argc - 2, argv + 2) != 0)
70 return(CMD_ERROR);
71 /* we have consumed all arguments */
72 argc = 1;
73 }
74
75 /*
76 * See if there is a kernel module already loaded
77 */
78 if (file_findfile(NULL, NULL) == NULL)
79 if (loadakernel(0, argc - 1, argv + 1))
80 /* we have consumed all arguments */
81 argc = 1;
82
83 /*
84 * Loaded anything yet?
85 */
86 if ((fp = file_findfile(NULL, NULL)) == NULL) {
87 command_errmsg = "no bootable kernel";
88 return(CMD_ERROR);
89 }
90
91 /*
92 * If we were given arguments, discard any previous.
93 * XXX should we merge arguments? Hard to DWIM.
94 */
95 if (argc > 1) {
96 if (fp->f_args != NULL)
97 free(fp->f_args);
98 fp->f_args = unargv(argc - 1, argv + 1);
99 }
100
101 /* Hook for platform-specific autoloading of modules */
102 if (archsw.arch_autoload() != 0)
103 return(CMD_ERROR);
104
105 /* Call the exec handler from the loader matching the kernel */
106 file_formats[fp->f_loader]->l_exec(fp);
107 return(CMD_ERROR);
108 }
109
110
111 /*
112 * Autoboot after a delay
113 */
114
115 COMMAND_SET(autoboot, "autoboot", "boot automatically after a delay", command_autoboot);
116
117 static int
118 command_autoboot(int argc, char *argv[])
119 {
120 int howlong;
121 char *cp, *prompt;
122
123 prompt = NULL;
124 howlong = -1;
125 switch(argc) {
126 case 3:
127 prompt = argv[2];
128 /* FALLTHROUGH */
129 case 2:
130 howlong = strtol(argv[1], &cp, 0);
131 if (*cp != 0) {
132 sprintf(command_errbuf, "bad delay '%s'", argv[1]);
133 return(CMD_ERROR);
134 }
135 /* FALLTHROUGH */
136 case 1:
137 return(autoboot(howlong, prompt));
138 }
139
140 command_errmsg = "too many arguments";
141 return(CMD_ERROR);
142 }
143
144 /*
145 * Called before we go interactive. If we think we can autoboot, and
146 * we haven't tried already, try now.
147 */
148 void
149 autoboot_maybe()
150 {
151 char *cp;
152
153 cp = getenv("autoboot_delay");
154 if ((autoboot_tried == 0) && ((cp == NULL) || strcasecmp(cp, "NO")))
155 autoboot(-1, NULL); /* try to boot automatically */
156 }
157
158 int
159 autoboot(int timeout, char *prompt)
160 {
161 time_t when, otime, ntime;
162 int c, yes;
163 char *argv[2], *cp, *ep;
164 char *kernelname;
165
166 autoboot_tried = 1;
167
168 if (timeout == -1) {
169 timeout = 10;
170 /* try to get a delay from the environment */
171 if ((cp = getenv("autoboot_delay"))) {
172 timeout = strtol(cp, &ep, 0);
173 if (cp == ep)
174 timeout = 10; /* Unparseable? Set default! */
175 }
176 }
177
178 kernelname = getenv("kernelname");
179 if (kernelname == NULL) {
180 argv[0] = NULL;
181 loadakernel(0, 0, argv);
182 kernelname = getenv("kernelname");
183 if (kernelname == NULL) {
184 command_errmsg = "no valid kernel found";
185 return(CMD_ERROR);
186 }
187 }
188
189 if (timeout >= 0) {
190 otime = time(NULL);
191 when = otime + timeout; /* when to boot */
192
193 yes = 0;
194
195 printf("%s\n", (prompt == NULL) ? "Hit [Enter] to boot immediately, or any other key for command prompt." : prompt);
196
197 for (;;) {
198 if (ischar()) {
199 c = getchar();
200 if ((c == '\r') || (c == '\n'))
201 yes = 1;
202 break;
203 }
204 ntime = time(NULL);
205 if (ntime >= when) {
206 yes = 1;
207 break;
208 }
209
210 if (ntime != otime) {
211 printf("\rBooting [%s] in %d second%s... ",
212 kernelname, (int)(when - ntime),
213 (when-ntime)==1?"":"s");
214 otime = ntime;
215 }
216 }
217 } else {
218 yes = 1;
219 }
220
221 if (yes)
222 printf("\rBooting [%s]... ", kernelname);
223 putchar('\n');
224 if (yes) {
225 argv[0] = "boot";
226 argv[1] = NULL;
227 return(command_boot(1, argv));
228 }
229 return(CMD_OK);
230 }
231
232 /*
233 * Scrounge for the name of the (try)'th file we will try to boot.
234 */
235 static char *
236 getbootfile(int try)
237 {
238 static char *name = NULL;
239 const char *spec, *ep;
240 size_t len;
241
242 /* we use dynamic storage */
243 if (name != NULL) {
244 free(name);
245 name = NULL;
246 }
247
248 /*
249 * Try $bootfile, then try our builtin default
250 */
251 if ((spec = getenv("bootfile")) == NULL)
252 spec = default_bootfiles;
253
254 while ((try > 0) && (spec != NULL)) {
255 spec = strchr(spec, ';');
256 if (spec)
257 spec++; /* skip over the leading ';' */
258 try--;
259 }
260 if (spec != NULL) {
261 if ((ep = strchr(spec, ';')) != NULL) {
262 len = ep - spec;
263 } else {
264 len = strlen(spec);
265 }
266 name = malloc(len + 1);
267 strncpy(name, spec, len);
268 name[len] = 0;
269 }
270 if (name && name[0] == 0) {
271 free(name);
272 name = NULL;
273 }
274 return(name);
275 }
276
277 /*
278 * Try to find the /etc/fstab file on the filesystem (rootdev),
279 * which should be be the root filesystem, and parse it to find
280 * out what the kernel ought to think the root filesystem is.
281 *
282 * If we're successful, set vfs.root.mountfrom to <vfstype>:<path>
283 * so that the kernel can tell both which VFS and which node to use
284 * to mount the device. If this variable's already set, don't
285 * overwrite it.
286 */
287 int
288 getrootmount(char *rootdev)
289 {
290 char lbuf[128], *cp, *ep, *dev, *fstyp;
291 int fd, error;
292
293 if (getenv("vfs.root.mountfrom") != NULL)
294 return(0);
295
296 sprintf(lbuf, "%s/etc/fstab", rootdev);
297 if ((fd = open(lbuf, O_RDONLY)) < 0)
298 return(1);
299
300 /* loop reading lines from /etc/fstab What was that about sscanf again? */
301 error = 1;
302 while (fgetstr(lbuf, sizeof(lbuf), fd) >= 0) {
303 if ((lbuf[0] == 0) || (lbuf[0] == '#'))
304 continue;
305
306 /* skip device name */
307 for (cp = lbuf; (*cp != 0) && !isspace(*cp); cp++)
308 ;
309 if (*cp == 0) /* misformatted */
310 continue;
311 /* delimit and save */
312 *cp++ = 0;
313 dev = strdup(lbuf);
314
315 /* skip whitespace up to mountpoint */
316 while ((*cp != 0) && isspace(*cp))
317 cp++;
318 /* must have /<space> to be root */
319 if ((*cp == 0) || (*cp != '/') || !isspace(*(cp + 1)))
320 continue;
321 /* skip whitespace up to fstype */
322 cp += 2;
323 while ((*cp != 0) && isspace(*cp))
324 cp++;
325 if (*cp == 0) /* misformatted */
326 continue;
327 /* skip text to end of fstype and delimit */
328 ep = cp;
329 while ((*cp != 0) && !isspace(*cp))
330 cp++;
331 *cp = 0;
332 fstyp = strdup(ep);
333
334 /* build the final result and save it */
335 sprintf(lbuf, "%s:%s", fstyp, dev);
336 free(dev);
337 free(fstyp);
338 setenv("vfs.root.mountfrom", lbuf, 0);
339 error = 0;
340 break;
341 }
342 close(fd);
343 return(error);
344 }
345
346 static int
347 loadakernel(int try, int argc, char* argv[])
348 {
349 char *cp;
350
351 for (try = 0; (cp = getbootfile(try)) != NULL; try++)
352 if (mod_loadkld(cp, argc - 1, argv + 1) != 0)
353 printf("can't load '%s'\n", cp);
354 else
355 return 1;
356 return 0;
357 }
Cache object: 3860bc5c3c070f141c5d21d35fe47de7
|