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  * $FreeBSD: src/sys/boot/common/boot.c,v 1.29 2003/08/25 23:30:41 obrien Exp $
  27  * $DragonFly: src/sys/boot/common/boot.c,v 1.4 2005/12/10 00:39:48 swildner Exp $
  28  */
  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(void)
 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         /* try to get a delay from the environment */
 170         if ((cp = getenv("autoboot_delay"))) {
 171             timeout = strtol(cp, &ep, 0);
 172             if (cp == ep)
 173                 timeout = -1;
 174         }
 175     }
 176     if (timeout == -1)          /* all else fails */
 177         timeout = 10;
 178
 179     kernelname = getenv("kernelname");
 180     if (kernelname == NULL) {
 181         argv[0] = NULL;
 182         loadakernel(0, 0, argv);
 183         kernelname = getenv("kernelname");
 184         if (kernelname == NULL) {
 185             command_errmsg = "no valid kernel found";
 186             return(CMD_ERROR);
 187         }
 188     }
 189
 190     otime = time(NULL);
 191     when = otime + timeout;     /* when to boot */
 192     yes = 0;
 193
 194     printf("%s\n", (prompt == NULL) ? "Hit [Enter] to boot immediately, or any other key for command prompt." : prompt);
 195
 196     for (;;) {
 197         if (ischar()) {
 198             c = getchar();
 199             if ((c == '\r') || (c == '\n'))
 200                 yes = 1;
 201             break;
 202         }
 203         ntime = time(NULL);
 204         if (ntime >= when) {
 205             yes = 1;
 206             break;
 207         }
 208
 209         if (ntime != otime) {
 210             printf("\rBooting [%s] in %d second%s... ",
 211                         kernelname, (int)(when - ntime),
 212                         (when-ntime)==1?"":"s");
 213             otime = ntime;
 214         }
 215     }
 216     if (yes)
 217         printf("\rBooting [%s]...               ", kernelname);
 218     putchar('\n');
 219     if (yes) {
 220         argv[0] = "boot";
 221         argv[1] = NULL;
 222         return(command_boot(1, argv));
 223     }
 224     return(CMD_OK);
 225 }
 226
 227 /*
 228  * Scrounge for the name of the (try)'th file we will try to boot.
 229  */
 230 static char *
 231 getbootfile(int try)
 232 {
 233     static char *name = NULL;
 234     const char  *spec, *ep;
 235     size_t      len;
 236
 237     /* we use dynamic storage */
 238     if (name != NULL) {
 239         free(name);
 240         name = NULL;
 241     }
 242
 243     /*
 244      * Try $bootfile, then try our builtin default
 245      */
 246     if ((spec = getenv("bootfile")) == NULL)
 247         spec = default_bootfiles;
 248
 249     while ((try > 0) && (spec != NULL)) {
 250         spec = strchr(spec, ';');
 251         if (spec)
 252             spec++;     /* skip over the leading ';' */
 253         try--;
 254     }
 255     if (spec != NULL) {
 256         if ((ep = strchr(spec, ';')) != NULL) {
 257             len = ep - spec;
 258         } else {
 259             len = strlen(spec);
 260         }
 261         name = malloc(len + 1);
 262         strncpy(name, spec, len);
 263         name[len] = 0;
 264     }
 265     if (name && name[0] == 0) {
 266         free(name);
 267         name = NULL;
 268     }
 269     return(name);
 270 }
 271
 272 /*
 273  * Try to find the /etc/fstab file on the filesystem (rootdev),
 274  * which should be be the root filesystem, and parse it to find
 275  * out what the kernel ought to think the root filesystem is.
 276  *
 277  * If we're successful, set vfs.root.mountfrom to <vfstype>:<path>
 278  * so that the kernel can tell both which VFS and which node to use
 279  * to mount the device.  If this variable's already set, don't
 280  * overwrite it.
 281  */
 282 int
 283 getrootmount(char *rootdev)
 284 {
 285     char        lbuf[128], *cp, *ep, *dev, *fstyp;
 286     int         fd, error;
 287
 288     if (getenv("vfs.root.mountfrom") != NULL)
 289         return(0);
 290
 291     sprintf(lbuf, "%s/etc/fstab", rootdev);
 292     if ((fd = open(lbuf, O_RDONLY)) < 0)
 293         return(1);
 294
 295     /* loop reading lines from /etc/fstab    What was that about sscanf again? */
 296     error = 1;
 297     while (fgetstr(lbuf, sizeof(lbuf), fd) >= 0) {
 298         if ((lbuf[0] == 0) || (lbuf[0] == '#'))
 299             continue;
 300
 301         /* skip device name */
 302         for (cp = lbuf; (*cp != 0) && !isspace(*cp); cp++)
 303             ;
 304         if (*cp == 0)           /* misformatted */
 305             continue;
 306         /* delimit and save */
 307         *cp++ = 0;
 308         dev = strdup(lbuf);
 309
 310         /* skip whitespace up to mountpoint */
 311         while ((*cp != 0) && isspace(*cp))
 312             cp++;
 313         /* must have /<space> to be root */
 314         if ((*cp == 0) || (*cp != '/') || !isspace(*(cp + 1)))
 315             continue;
 316         /* skip whitespace up to fstype */
 317         cp += 2;
 318         while ((*cp != 0) && isspace(*cp))
 319             cp++;
 320         if (*cp == 0)           /* misformatted */
 321             continue;
 322         /* skip text to end of fstype and delimit */
 323         ep = cp;
 324         while ((*cp != 0) && !isspace(*cp))
 325             cp++;
 326         *cp = 0;
 327         fstyp = strdup(ep);
 328
 329         /* build the final result and save it */
 330         sprintf(lbuf, "%s:%s", fstyp, dev);
 331         free(dev);
 332         free(fstyp);
 333         setenv("vfs.root.mountfrom", lbuf, 0);
 334         error = 0;
 335         break;
 336     }
 337     close(fd);
 338     return(error);
 339 }
 340
 341 static int
 342 loadakernel(int try, int argc, char* argv[])
 343 {
 344     char *cp;
 345
 346         for (try = 0; (cp = getbootfile(try)) != NULL; try++)
 347             if (mod_loadkld(cp, argc - 1, argv + 1) != 0)
 348                 printf("can't load '%s'\n", cp);
 349             else
 350                 return 1;
 351         return 0;
 352 }
 353