/*
 * Copyright (c) 1998 Michael Smith <msmith@freebsd.org>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include <sys/cdefs.h>

/*
 * Loading modules, booting the system
 */

#include <stand.h>
#include <string.h>

#include "bootstrap.h"

static char     *getbootfile(int try);
static int      loadakernel(int try, int argc, char *argv[]);

/*
 * List of kernel names to try (may be overwritten by boot.config)
 * XXX should move from here?
 */
static const char *default_bootfiles = "kernel";

static int autoboot_tried;

/*
 * The user wants us to boot.
 */
COMMAND_SET(boot, "boot", "boot a file or loaded kernel", command_boot);

static int
command_boot(int argc, char *argv[])
{
        struct preloaded_file *fp;

        /*
         * See if the user has specified an explicit kernel to boot.
         */
        if ((argc > 1) && (argv[1][0] == '/')) {

                /* XXX maybe we should discard everything and start again? */
                if (file_findfile(NULL, NULL) != NULL) {
                        snprintf(command_errbuf, sizeof (command_errbuf),
                            "can't boot '%s', kernel module already loaded",
                            argv[1]);
                        return (CMD_ERROR);
                }

                /* find/load the kernel module */
                if (mod_loadkld(argv[1], argc - 2, argv + 2) != 0)
                        return (CMD_ERROR);
                /* we have consumed all arguments */
                argc = 1;
        }

        /*
         * See if there is a kernel module already loaded
         */
        if (file_findfile(NULL, NULL) == NULL)
                if (loadakernel(0, argc - 1, argv + 1)) {
                        /* we have consumed all arguments */
                        argc = 1;
                }

        /*
         * Loaded anything yet?
         */
        if ((fp = file_findfile(NULL, NULL)) == NULL) {
                command_errmsg = "no bootable kernel";
                return (CMD_ERROR);
        }

        /*
         * If we were given arguments, discard any previous.
         * XXX should we merge arguments?  Hard to DWIM.
         */
        if (argc > 1) {
                free(fp->f_args);
                fp->f_args = unargv(argc - 1, argv + 1);
        }

        /* Hook for platform-specific autoloading of modules */
        if (archsw.arch_autoload() != 0)
                return (CMD_ERROR);

        /* Call the exec handler from the loader matching the kernel */
        file_formats[fp->f_loader]->l_exec(fp);
        return (CMD_ERROR);
}


/*
 * Autoboot after a delay
 */

COMMAND_SET(autoboot, "autoboot", "boot automatically after a delay",
    command_autoboot);

static int
command_autoboot(int argc, char *argv[])
{
        int howlong;
        char *cp, *prompt;

        prompt = NULL;
        howlong = -1;
        switch (argc) {
        case 3:
                prompt = argv[2];
                /* FALLTHROUGH */
        case 2:
                howlong = strtol(argv[1], &cp, 0);
                if (*cp != 0) {
                        snprintf(command_errbuf, sizeof (command_errbuf),
                            "bad delay '%s'", argv[1]);
                        return (CMD_ERROR);
                }
                /* FALLTHROUGH */
        case 1:
                return (autoboot(howlong, prompt));
        }

        command_errmsg = "too many arguments";
        return (CMD_ERROR);
}

/*
 * Called before we go interactive.  If we think we can autoboot, and
 * we haven't tried already, try now.
 */
void
autoboot_maybe(void)
{
        char *cp;

        /* compatibility with sparc prom, check for autoboot? */
        cp = getenv("autoboot?");
        if (cp != NULL && strcasecmp(cp, "true") != 0)
                return;
        cp = getenv("autoboot_delay");
        if ((autoboot_tried == 0) && ((cp == NULL) || strcasecmp(cp, "NO")))
                autoboot(-1, NULL);             /* try to boot automatically */
}

int
autoboot(int timeout, char *prompt)
{
        time_t when, otime, ntime;
        int c, yes;
        char *argv[2], *cp, *ep;
        char *kernelname;
        struct preloaded_file *fp;

        autoboot_tried = 1;

        if (timeout == -1) {
                timeout = 10;
                /* try to get a delay from the environment */
                if ((cp = getenv("autoboot_delay"))) {
                        timeout = strtol(cp, &ep, 0);
                        if (cp == ep)
                                timeout = 10;   /* Unparseable? Set default! */
                }
        }

        fp = file_findfile(NULL, NULL);
        if (fp == NULL) {
                /* no preloaded files, run command start to load all */
                bf_run("start");
                fp = file_findfile(NULL, NULL);
                if (fp == NULL) { /* still nothing? can't boot */
                        command_errmsg = "no valid kernel found";
                        return (CMD_ERROR);
                }
        }

        kernelname = fp->f_name;

        if (timeout >= 0) {
                otime = time(NULL);
                when = otime + timeout; /* when to boot */

                yes = 0;

                printf("%s\n", (prompt == NULL) ?
                    "Hit [Enter] to boot immediately, or any other key "
                    "for command prompt." : prompt);

                for (;;) {
                        if (ischar()) {
                                c = getchar();
                                if ((c == '\r') || (c == '\n'))
                                        yes = 1;
                                break;
                        }
                        ntime = time(NULL);
                        if (ntime >= when) {
                                yes = 1;
                                break;
                        }

                        if (ntime != otime) {
                                printf("\rBooting [%s] in %d second%s... ",
                                    kernelname, (int)(when - ntime),
                                    (when - ntime) == 1? "":"s");
                                otime = ntime;
                        }
                }
        } else {
                yes = 1;
        }

        if (yes)
                printf("\rBooting [%s]...               ", kernelname);
        putchar('\n');
        if (yes) {
                argv[0] = "boot";
                argv[1] = NULL;
                return (command_boot(1, argv));
        }
        return (CMD_OK);
}

/*
 * Scrounge for the name of the (try)'th file we will try to boot.
 */
static char *
getbootfile(int try)
{
        static char *name = NULL;
        const char *spec, *ep;
        size_t len;

        /* we use dynamic storage */
        free(name);
        name = NULL;

        /*
         * Try $bootfile, then try our builtin default
         */
        if ((spec = getenv("bootfile")) == NULL)
                spec = default_bootfiles;

        while ((try > 0) && (spec != NULL)) {
                spec = strchr(spec, ';');
                if (spec)
                        spec++; /* skip over the leading ';' */
                try--;
        }
        if (spec != NULL) {
                if ((ep = strchr(spec, ';')) != NULL) {
                        len = ep - spec;
                } else {
                        len = strlen(spec);
                }
                name = malloc(len + 1);
                strncpy(name, spec, len);
                name[len] = 0;
        }
        if (name && name[0] == 0) {
                free(name);
                name = NULL;
        }
        return (name);
}

/*
 * Try to find the /etc/fstab file on the filesystem (rootdev),
 * which should be be the root filesystem, and parse it to find
 * out what the kernel ought to think the root filesystem is.
 *
 * If we're successful, set vfs.root.mountfrom to <vfstype>:<path>
 * so that the kernel can tell both which VFS and which node to use
 * to mount the device.  If this variable's already set, don't
 * overwrite it.
 */
int
getrootmount(char *rootdev)
{
        char lbuf[128], *cp, *ep, *dev, *fstyp, *options;
        int fd, error;

        if (getenv("vfs.root.mountfrom") != NULL)
                return (0);

        error = 1;
        sprintf(lbuf, "%s/etc/fstab", rootdev);
        if ((fd = open(lbuf, O_RDONLY)) < 0)
                goto notfound;

        /*
         * loop reading lines from /etc/fstab
         * What was that about sscanf again?
         */
        fstyp = NULL;
        dev = NULL;
        while (fgetstr(lbuf, sizeof (lbuf), fd) >= 0) {
                if ((lbuf[0] == 0) || (lbuf[0] == '#'))
                        continue;

                /* skip device name */
                for (cp = lbuf; (*cp != 0) && !isspace(*cp); cp++)
                        ;
                if (*cp == 0)           /* misformatted */
                        continue;
                /* delimit and save */
                *cp++ = 0;
                free(dev);
                dev = strdup(lbuf);

                /* skip whitespace up to mountpoint */
                while ((*cp != 0) && isspace(*cp))
                        cp++;
                /* must have /<space> to be root */
                if ((*cp == 0) || (*cp != '/') || !isspace(*(cp + 1)))
                        continue;
                /* skip whitespace up to fstype */
                cp += 2;
                while ((*cp != 0) && isspace(*cp))
                        cp++;
                if (*cp == 0)           /* misformatted */
                        continue;
                /* skip text to end of fstype and delimit */
                ep = cp;
                while ((*cp != 0) && !isspace(*cp))
                        cp++;
                *cp = 0;
                free(fstyp);
                fstyp = strdup(ep);

                /* skip whitespace up to mount options */
                cp += 1;
                while ((*cp != 0) && isspace(*cp))
                        cp++;
                if (*cp == 0)           /* misformatted */
                        continue;
                /* skip text to end of mount options and delimit */
                ep = cp;
                while ((*cp != 0) && !isspace(*cp))
                        cp++;
                *cp = 0;
                options = strdup(ep);
                /*
                 * Build the <fstype>:<device> and save it in
                 * vfs.root.mountfrom
                 */
                sprintf(lbuf, "%s:%s", fstyp, dev);
                setenv("vfs.root.mountfrom", lbuf, 0);

                /*
                 * Don't override vfs.root.mountfrom.options if it is
                 * already set
                 */
                if (getenv("vfs.root.mountfrom.options") == NULL) {
                        /* save mount options */
                        setenv("vfs.root.mountfrom.options", options, 0);
                }
                free(options);
                error = 0;
                break;
        }
        close(fd);
        free(dev);
        free(fstyp);

notfound:
        if (error) {
                const char *currdev;

                currdev = getenv("currdev");
                if (currdev != NULL && strncmp("zfs:", currdev, 4) == 0) {
                        cp = strdup(currdev);
                        cp[strlen(cp) - 1] = '\0';
                        setenv("vfs.root.mountfrom", cp, 0);
                        error = 0;
                        free(cp);
                }
        }

        return (error);
}

static int
loadakernel(int try, int argc, char *argv[])
{
        char *cp;

        for (try = 0; (cp = getbootfile(try)) != NULL; try++)
                if (mod_loadkld(cp, argc - 1, argv + 1) != 0)
                        printf("can't load '%s'\n", cp);
                else
                        return (1);
        return (0);
}