root/usr/src/common/ficl/emu/loader_emu.c
/*
 * Copyright (c) 1998 Michael Smith <msmith@freebsd.org>
 * Copyright 2019 OmniOS Community Edition (OmniOSce) Association.
 * 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/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <errno.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <strings.h>
#include <limits.h>
#include <unistd.h>
#include <dirent.h>
#include <macros.h>
#include <sys/systeminfo.h>
#include <sys/linker_set.h>
#include <sys/queue.h>
#include <sys/mnttab.h>
#include "loader_emu.h"
#include "gfx_fb.h"
#include "ficl.h"

#define MDIR_REMOVED    0x0001
#define MDIR_NOHINTS    0x0002

struct moduledir {
        char    *d_path;        /* path of modules directory */
        uchar_t *d_hints;       /* content of linker.hints file */
        int     d_hintsz;       /* size of hints data */
        int     d_flags;
        STAILQ_ENTRY(moduledir) d_link;
};
static STAILQ_HEAD(, moduledir) moduledir_list =
    STAILQ_HEAD_INITIALIZER(moduledir_list);

static const char *default_searchpath = "/platform/i86pc";

static char typestr[] = "?fc?d?b? ?l?s?w";
static int      ls_getdir(char **pathp);
extern char **_environ;

char    *command_errmsg;
char    command_errbuf[256];

extern void pager_open(void);
extern void pager_close(void);
extern int pager_output(const char *);
extern int pager_file(const char *);
static int page_file(char *);
static int include(const char *);

static int command_help(int argc, char *argv[]);
static int command_commandlist(int argc, char *argv[]);
static int command_show(int argc, char *argv[]);
static int command_set(int argc, char *argv[]);
static int command_setprop(int argc, char *argv[]);
static int command_unset(int argc, char *argv[]);
static int command_echo(int argc, char *argv[]);
static int command_read(int argc, char *argv[]);
static int command_more(int argc, char *argv[]);
static int command_ls(int argc, char *argv[]);
static int command_include(int argc, char *argv[]);
static int command_autoboot(int argc, char *argv[]);
static int command_boot(int argc, char *argv[]);
static int command_unload(int argc, char *argv[]);
static int command_load(int argc, char *argv[]);
static int command_reboot(int argc, char *argv[]);
static int command_sifting(int argc, char *argv[]);
static int command_framebuffer(int argc, char *argv[]);

#define BF_PARSE        100
#define BF_DICTSIZE     30000

/* update when loader version will change */
static const char bootprog_rev[] = "1.1";

/*
 * BootForth   Interface to Ficl Forth interpreter.
 */

ficlSystem *bf_sys;
ficlVm  *bf_vm;

/*
 * 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.
 *
 * Jordan K. Hubbard
 * 29 August 1998
 *
 * The meat of the simple parser.
 */

static void      clean(void);
static int       insert(int *argcp, char *buf);

#define PARSE_BUFSIZE   1024    /* maximum size of one element */
#define MAXARGS         20      /* maximum number of elements */
static  char            *args[MAXARGS];

#define DIGIT(x)        \
        (isdigit(x) ? (x) - '0' : islower(x) ? (x) + 10 - 'a' : (x) + 10 - 'A')

/*
 * backslash: Return malloc'd copy of str with all standard "backslash
 * processing" done on it.  Original can be free'd if desired.
 */
char *
backslash(char *str)
{
        /*
         * Remove backslashes from the strings. Turn \040 etc. into a single
         * character (we allow eight bit values). Currently NUL is not
         * allowed.
         *
         * Turn "\n" and "\t" into '\n' and '\t' characters. Etc.
         */
        char *new_str;
        int seenbs = 0;
        int i = 0;

        if ((new_str = strdup(str)) == NULL)
                return (NULL);

        while (*str) {
                if (seenbs) {
                        seenbs = 0;
                        switch (*str) {
                        case '\\':
                                new_str[i++] = '\\';
                                str++;
                        break;

                        /* preserve backslashed quotes, dollar signs */
                        case '\'':
                        case '"':
                        case '$':
                                new_str[i++] = '\\';
                                new_str[i++] = *str++;
                        break;

                        case 'b':
                                new_str[i++] = '\b';
                                str++;
                        break;

                        case 'f':
                                new_str[i++] = '\f';
                                str++;
                        break;

                        case 'r':
                                new_str[i++] = '\r';
                                str++;
                        break;

                        case 'n':
                                new_str[i++] = '\n';
                                str++;
                        break;

                        case 's':
                                new_str[i++] = ' ';
                                str++;
                        break;

                        case 't':
                                new_str[i++] = '\t';
                                str++;
                        break;

                        case 'v':
                                new_str[i++] = '\13';
                                str++;
                        break;

                        case 'z':
                                str++;
                        break;

                        case '0': case '1': case '2': case '3': case '4':
                        case '5': case '6': case '7': case '8': case '9': {
                                char val;

                                /* Three digit octal constant? */
                                if (*str >= '0' && *str <= '3' &&
                                    *(str + 1) >= '0' && *(str + 1) <= '7' &&
                                    *(str + 2) >= '0' && *(str + 2) <= '7') {

                                        val = (DIGIT(*str) << 6) +
                                            (DIGIT(*(str + 1)) << 3) +
                                            DIGIT(*(str + 2));

                                        /*
                                         * Allow null value if user really
                                         * wants to shoot at feet, but beware!
                                         */
                                        new_str[i++] = val;
                                        str += 3;
                                        break;
                                }

                                /*
                                 * One or two digit hex constant?
                                 * If two are there they will both be taken.
                                 * Use \z to split them up if this is not
                                 * wanted.
                                 */
                                if (*str == '0' &&
                                    (*(str + 1) == 'x' || *(str + 1) == 'X') &&
                                    isxdigit(*(str + 2))) {
                                        val = DIGIT(*(str + 2));
                                        if (isxdigit(*(str + 3))) {
                                                val = (val << 4) +
                                                    DIGIT(*(str + 3));
                                                str += 4;
                                        } else
                                                str += 3;
                                        /* Yep, allow null value here too */
                                        new_str[i++] = val;
                                        break;
                                }
                        }
                        break;

                        default:
                                new_str[i++] = *str++;
                        break;
                        }
                } else {
                        if (*str == '\\') {
                                seenbs = 1;
                                str++;
                        } else
                                new_str[i++] = *str++;
                }
        }

        if (seenbs) {
                /*
                 * The final character was a '\'.
                 * Put it in as a single backslash.
                 */
                new_str[i++] = '\\';
        }
        new_str[i] = '\0';
        return (new_str);
}

/*
 * parse: accept a string of input and "parse" it for backslash
 * substitutions and environment variable expansions (${var}),
 * returning an argc/argv style vector of whitespace separated
 * arguments.  Returns 0 on success, 1 on failure (ok, ok, so I
 * wimped-out on the error codes! :).
 *
 * Note that the argv array returned must be freed by the caller, but
 * we own the space allocated for arguments and will free that on next
 * invocation.  This allows argv consumers to modify the array if
 * required.
 *
 * NB: environment variables that expand to more than one whitespace
 * separated token will be returned as a single argv[] element, not
 * split in turn.  Expanded text is also immune to further backslash
 * elimination or expansion since this is a one-pass, non-recursive
 * parser.  You didn't specify more than this so if you want more, ask
 * me. - jkh
 */

#define PARSE_FAIL(expr)        \
if (expr) { \
    printf("fail at line %d\n", __LINE__); \
    clean(); \
    free(copy); \
    free(buf); \
    return (1); \
}

/* Accept the usual delimiters for a variable, returning counterpart */
static char
isdelim(int ch)
{
        if (ch == '{')
                return ('}');
        else if (ch == '(')
                return (')');
        return ('\0');
}

static int
isquote(int ch)
{
        return (ch == '\'');
}

static int
isdquote(int ch)
{
        return (ch == '"');
}

int
parse(int *argc, char ***argv, char *str)
{
        int ac;
        char *val, *p, *q, *copy = NULL;
        size_t i = 0;
        char token, tmp, quote, dquote, *buf;
        enum { STR, VAR, WHITE } state;

        ac = *argc = 0;
        dquote = quote = 0;
        if (!str || (p = copy = backslash(str)) == NULL)
                return (1);

        /* Initialize vector and state */
        clean();
        state = STR;
        buf = (char *)malloc(PARSE_BUFSIZE);
        token = 0;

        /* And awaaaaaaaaay we go! */
        while (*p) {
                switch (state) {
                case STR:
                        if ((*p == '\\') && p[1]) {
                                p++;
                                PARSE_FAIL(i == (PARSE_BUFSIZE - 1));
                                buf[i++] = *p++;
                        } else if (isquote(*p)) {
                                quote = quote ? 0 : *p;
                                if (dquote) { /* keep quote */
                                        PARSE_FAIL(i == (PARSE_BUFSIZE - 1));
                                        buf[i++] = *p++;
                                } else
                                        ++p;
                        } else if (isdquote(*p)) {
                                dquote = dquote ? 0 : *p;
                                if (quote) { /* keep dquote */
                                        PARSE_FAIL(i == (PARSE_BUFSIZE - 1));
                                        buf[i++] = *p++;
                                } else
                                        ++p;
                        } else if (isspace(*p) && !quote && !dquote) {
                                state = WHITE;
                                if (i) {
                                        buf[i] = '\0';
                                        PARSE_FAIL(insert(&ac, buf));
                                        i = 0;
                                }
                                ++p;
                        } else if (*p == '$' && !quote) {
                                token = isdelim(*(p + 1));
                                if (token)
                                        p += 2;
                                else
                                        ++p;
                                state = VAR;
                        } else {
                                PARSE_FAIL(i == (PARSE_BUFSIZE - 1));
                                buf[i++] = *p++;
                        }
                break;

                case WHITE:
                        if (isspace(*p))
                                ++p;
                        else
                                state = STR;
                break;

                case VAR:
                        if (token) {
                                PARSE_FAIL((q = strchr(p, token)) == NULL);
                        } else {
                                q = p;
                                while (*q && !isspace(*q))
                                        ++q;
                        }
                        tmp = *q;
                        *q = '\0';
                        if ((val = getenv(p)) != NULL) {
                                size_t len = strlen(val);

                                (void) strncpy(buf + i, val,
                                    PARSE_BUFSIZE - (i + 1));
                                i += min(len, PARSE_BUFSIZE - 1);
                        }
                        *q = tmp;       /* restore value */
                        p = q + (token ? 1 : 0);
                        state = STR;
                break;
                }
        }
        /* missing terminating ' or " */
        PARSE_FAIL(quote || dquote);
        /* If at end of token, add it */
        if (i && state == STR) {
                buf[i] = '\0';
                PARSE_FAIL(insert(&ac, buf));
        }
        args[ac] = NULL;
        *argc = ac;
        *argv = (char **)malloc((sizeof (char *) * ac + 1));
        bcopy(args, *argv, sizeof (char *) * ac + 1);
        free(buf);
        free(copy);
        return (0);
}

#define MAXARGS 20

/* Clean vector space */
static void
clean(void)
{
        int i;

        for (i = 0; i < MAXARGS; i++) {
                if (args[i] != NULL) {
                        free(args[i]);
                        args[i] = NULL;
                }
        }
}

static int
insert(int *argcp, char *buf)
{
        if (*argcp >= MAXARGS)
                return (1);
        args[(*argcp)++] = strdup(buf);
        return (0);
}

static char *
isadir(void)
{
        char *buf;
        size_t bufsize = 20;
        int ret;

        if ((buf = malloc(bufsize)) == NULL)
                return (NULL);
        ret = sysinfo(SI_ARCHITECTURE_K, buf, bufsize);
        if (ret == -1) {
                free(buf);
                return (NULL);
        }
        return (buf);
}

/*
 * Shim for taking commands from BF and passing them out to 'standard'
 * argv/argc command functions.
 */
static void
bf_command(ficlVm *vm)
{
        char *name, *line, *tail, *cp;
        size_t len;
        struct bootblk_command **cmdp;
        bootblk_cmd_t *cmd;
        int nstrings, i;
        int argc, result;
        char **argv;

        /* Get the name of the current word */
        name = vm->runningWord->name;

        /* Find our command structure */
        cmd = NULL;
        SET_FOREACH(cmdp, Xcommand_set) {
                if (((*cmdp)->c_name != NULL) &&
                    strcmp(name, (*cmdp)->c_name) == 0)
                        cmd = (*cmdp)->c_fn;
        }
        if (cmd == NULL)
                printf("callout for unknown command '%s'\n", name);

        /* Check whether we have been compiled or are being interpreted */
        if (ficlStackPopInteger(ficlVmGetDataStack(vm))) {
                /*
                 * Get parameters from stack, in the format:
                 * an un ... a2 u2 a1 u1 n --
                 * Where n is the number of strings, a/u are pairs of
                 * address/size for strings, and they will be concatenated
                 * in LIFO order.
                 */
                nstrings = ficlStackPopInteger(ficlVmGetDataStack(vm));
                for (i = 0, len = 0; i < nstrings; i++)
                        len += ficlStackFetch(ficlVmGetDataStack(vm),
                            i * 2).i + 1;
                line = malloc(strlen(name) + len + 1);
                (void) strcpy(line, name);

                if (nstrings)
                        for (i = 0; i < nstrings; i++) {
                                len = ficlStackPopInteger(
                                    ficlVmGetDataStack(vm));
                                cp = ficlStackPopPointer(
                                    ficlVmGetDataStack(vm));
                                (void) strcat(line, " ");
                                (void) strncat(line, cp, len);
                        }
        } else {
                /* Get remainder of invocation */
                tail = ficlVmGetInBuf(vm);
                for (cp = tail, len = 0;
                    cp != vm->tib.end && *cp != 0 && *cp != '\n'; cp++, len++)
                        ;

                line = malloc(strlen(name) + len + 2);
                (void) strcpy(line, name);
                if (len > 0) {
                        (void) strcat(line, " ");
                        (void) strncat(line, tail, len);
                        ficlVmUpdateTib(vm, tail + len);
                }
        }

        command_errmsg = command_errbuf;
        command_errbuf[0] = 0;
        if (!parse(&argc, &argv, line)) {
                result = (cmd)(argc, argv);
                free(argv);
        } else {
                result = BF_PARSE;
        }
        free(line);
        /*
         * If there was error during nested ficlExec(), we may no longer have
         * valid environment to return.  Throw all exceptions from here.
         */
        if (result != 0)
                ficlVmThrow(vm, result);
        /* This is going to be thrown!!! */
        ficlStackPushInteger(ficlVmGetDataStack(vm), result);
}

static char *
get_currdev(void)
{
        int ret;
        char *currdev;
        FILE *fp;
        struct mnttab mpref = {0};
        struct mnttab mp = {0};

        mpref.mnt_mountp = "/";
        fp = fopen(MNTTAB, "r");

        /* do the best we can to return something... */
        if (fp == NULL)
                return (strdup(":"));

        ret = getmntany(fp, &mp, &mpref);
        (void) fclose(fp);
        if (ret == 0)
                (void) asprintf(&currdev, "zfs:%s:", mp.mnt_special);
        else
                return (strdup(":"));

        return (currdev);
}

/*
 * Replace a word definition (a builtin command) with another
 * one that:
 *
 *        - Throw error results instead of returning them on the stack
 *        - Pass a flag indicating whether the word was compiled or is
 *          being interpreted.
 *
 * There is one major problem with builtins that cannot be overcome
 * in anyway, except by outlawing it. We want builtins to behave
 * differently depending on whether they have been compiled or they
 * are being interpreted. Notice that this is *not* the interpreter's
 * current state. For example:
 *
 * : example ls ; immediate
 * : problem example ;          \ "ls" gets executed while compiling
 * example                      \ "ls" gets executed while interpreting
 *
 * Notice that, though the current state is different in the two
 * invocations of "example", in both cases "ls" has been
 * *compiled in*, which is what we really want.
 *
 * The problem arises when you tick the builtin. For example:
 *
 * : example-1 ['] ls postpone literal ; immediate
 * : example-2 example-1 execute ; immediate
 * : problem example-2 ;
 * example-2
 *
 * We have no way, when we get EXECUTEd, of knowing what our behavior
 * should be. Thus, our only alternative is to "outlaw" this. See RFI
 * 0007, and ANS Forth Standard's appendix D, item 6.7 for a related
 * problem, concerning compile semantics.
 *
 * The problem is compounded by the fact that "' builtin CATCH" is valid
 * and desirable. The only solution is to create an intermediary word.
 * For example:
 *
 * : my-ls ls ;
 * : example ['] my-ls catch ;
 *
 * So, with the below implementation, here is a summary of the behavior
 * of builtins:
 *
 * ls -l                                \ "interpret" behavior, ie,
 *                                      \ takes parameters from TIB
 * : ex-1 s" -l" 1 ls ;                 \ "compile" behavior, ie,
 *                                      \ takes parameters from the stack
 * : ex-2 ['] ls catch ; immediate      \ undefined behavior
 * : ex-3 ['] ls catch ;                \ undefined behavior
 * ex-2 ex-3                            \ "interpret" behavior,
 *                                      \ catch works
 * : ex-4 ex-2 ;                        \ "compile" behavior,
 *                                      \ catch does not work
 * : ex-5 ex-3 ; immediate              \ same as ex-2
 * : ex-6 ex-3 ;                        \ same as ex-3
 * : ex-7 ['] ex-1 catch ;              \ "compile" behavior,
 *                                      \ catch works
 * : ex-8 postpone ls ; immediate       \ same as ex-2
 * : ex-9 postpone ls ;                 \ same as ex-3
 *
 * As the definition below is particularly tricky, and it's side effects
 * must be well understood by those playing with it, I'll be heavy on
 * the comments.
 *
 * (if you edit this definition, pay attention to trailing spaces after
 *  each word -- I warned you! :-) )
 */
#define BUILTIN_CONSTRUCTOR \
": builtin: "           \
">in @ "                /* save the tib index pointer */ \
"' "                    /* get next word's xt */ \
"swap >in ! "           /* point again to next word */ \
"create "               /* create a new definition of the next word */ \
", "                    /* save previous definition's xt */ \
"immediate "            /* make the new definition an immediate word */ \
                        \
"does> "                /* Now, the *new* definition will: */ \
"state @ if "           /* if in compiling state: */ \
"1 postpone literal "   /* pass 1 flag to indicate compile */ \
"@ compile, "           /* compile in previous definition */ \
"postpone throw "               /* throw stack-returned result */ \
"else "         /* if in interpreting state: */ \
"0 swap "                       /* pass 0 flag to indicate interpret */ \
"@ execute "            /* call previous definition */ \
"throw "                        /* throw stack-returned result */ \
"then ; "

extern int ficlExecFD(ficlVm *, int);

/*
 * Initialise the Forth interpreter, create all our commands as words.
 */
ficlVm *
bf_init(const char *rc, ficlOutputFunction out)
{
        struct bootblk_command **cmdp;
        char create_buf[41];    /* 31 characters-long builtins */
        char *buf;
        int fd, rv;
        ficlSystemInformation *fsi;
        ficlDictionary *dict;
        ficlDictionary *env;

        fsi = malloc(sizeof (ficlSystemInformation));
        ficlSystemInformationInitialize(fsi);
        fsi->textOut = out;
        fsi->dictionarySize = BF_DICTSIZE;

        bf_sys = ficlSystemCreate(fsi);
        free(fsi);
        ficlSystemCompileExtras(bf_sys);
        bf_vm = ficlSystemCreateVm(bf_sys);

        buf = isadir();
        if (buf == NULL || strcmp(buf, "amd64") != 0) {
                (void) setenv("ISADIR", "", 1);
        } else {
                (void) setenv("ISADIR", buf, 1);
        }
        if (buf != NULL)
                free(buf);
        buf = get_currdev();
        (void) setenv("currdev", buf, 1);
        free(buf);
        (void) setenv("console", "text", 1);

        /* Put all private definitions in a "builtins" vocabulary */
        rv = ficlVmEvaluate(bf_vm,
            "vocabulary builtins also builtins definitions");
        if (rv != FICL_VM_STATUS_OUT_OF_TEXT) {
                printf("error interpreting forth: %d\n", rv);
                exit(1);
        }

        /* Builtin constructor word  */
        rv = ficlVmEvaluate(bf_vm, BUILTIN_CONSTRUCTOR);
        if (rv != FICL_VM_STATUS_OUT_OF_TEXT) {
                printf("error interpreting forth: %d\n", rv);
                exit(1);
        }

        /* make all commands appear as Forth words */
        dict = ficlSystemGetDictionary(bf_sys);
        cmdp = NULL;

        SET_FOREACH(cmdp, Xcommand_set) {
                (void) ficlDictionaryAppendPrimitive(dict,
                    (char *)(*cmdp)->c_name, bf_command, FICL_WORD_DEFAULT);
                rv = ficlVmEvaluate(bf_vm, "forth definitions builtins");
                if (rv != FICL_VM_STATUS_OUT_OF_TEXT) {
                        printf("error interpreting forth: %d\n", rv);
                        exit(1);
                }
                (void) snprintf(create_buf, sizeof (create_buf), "builtin: %s",
                    (*cmdp)->c_name);
                rv = ficlVmEvaluate(bf_vm, create_buf);
                if (rv != FICL_VM_STATUS_OUT_OF_TEXT) {
                        printf("error interpreting forth: %d\n", rv);
                        exit(1);
                }
                rv = ficlVmEvaluate(bf_vm, "builtins definitions");
                if (rv != FICL_VM_STATUS_OUT_OF_TEXT) {
                        printf("error interpreting forth: %d\n", rv);
                        exit(1);
                }
        }
        rv = ficlVmEvaluate(bf_vm, "only forth definitions");
        if (rv != FICL_VM_STATUS_OUT_OF_TEXT) {
                printf("error interpreting forth: %d\n", rv);
                exit(1);
        }

        /*
         * Export some version numbers so that code can detect the
         * loader/host version
         */
        env = ficlSystemGetEnvironment(bf_sys);
        (void) ficlDictionarySetConstant(env, "loader_version",
            (bootprog_rev[0] - '0') * 10 + (bootprog_rev[2] - '0'));

        /* try to load and run init file if present */
        if (rc == NULL)
                rc = "/boot/forth/boot.4th";
        if (*rc != '\0') {
                fd = open(rc, O_RDONLY);
                if (fd != -1) {
                        (void) ficlExecFD(bf_vm, fd);
                        (void) close(fd);
                }
        }

        gfx_framework_init();
        return (bf_vm);
}

void
bf_fini(void)
{
        ficlSystemDestroy(bf_sys);
        gfx_framework_fini();
}

/*
 * Feed a line of user input to the Forth interpreter
 */
int
bf_run(char *line)
{
        int result;
        ficlString s;

        FICL_STRING_SET_FROM_CSTRING(s, line);
        result = ficlVmExecuteString(bf_vm, s);

        switch (result) {
        case FICL_VM_STATUS_OUT_OF_TEXT:
        case FICL_VM_STATUS_ABORTQ:
        case FICL_VM_STATUS_QUIT:
        case FICL_VM_STATUS_ERROR_EXIT:
        break;
        case FICL_VM_STATUS_USER_EXIT:
        break;
        case FICL_VM_STATUS_ABORT:
                printf("Aborted!\n");
        break;
        case BF_PARSE:
                printf("Parse error!\n");
        break;
        default:
                if (command_errmsg != NULL) {
                        printf("%s\n", command_errmsg);
                        command_errmsg = NULL;
                }
        }

        (void) setenv("interpret", bf_vm->state ? "" : "ok", 1);

        return (result);
}

char *
get_dev(const char *path)
{
        FILE *fp;
        struct mnttab mpref = {0};
        struct mnttab mp = {0};
        char *currdev;
        int ret;
        char *buf;
        char *tmppath;
        char *tmpdev;
        char *cwd = NULL;

        fp = fopen(MNTTAB, "r");

        /* do the best we can to return something... */
        if (fp == NULL)
                return (strdup(path));

        /*
         * the path can have device provided, check for it
         * and extract it.
         */
        buf = strrchr(path, ':');
        if (buf != NULL) {
                tmppath = buf+1;                /* real path */
                buf = strchr(path, ':');        /* skip zfs: */
                buf++;
                tmpdev = strdup(buf);
                buf = strchr(tmpdev, ':');      /* get ending : */
                *buf = '\0';
        } else {
                tmppath = (char *)path;
                if (tmppath[0] != '/')
                        if ((cwd = getcwd(NULL, PATH_MAX)) == NULL) {
                                (void) fclose(fp);
                                return (strdup(path));
                        }

                currdev = getenv("currdev");
                buf = strchr(currdev, ':');     /* skip zfs: */
                if (buf == NULL) {
                        (void) fclose(fp);
                        return (strdup(path));
                }
                buf++;
                tmpdev = strdup(buf);
                buf = strchr(tmpdev, ':');      /* get ending : */
                *buf = '\0';
        }

        mpref.mnt_special = tmpdev;
        ret = getmntany(fp, &mp, &mpref);
        (void) fclose(fp);
        free(tmpdev);

        if (cwd == NULL)
                (void) asprintf(&buf, "%s/%s", ret? "":mp.mnt_mountp, tmppath);
        else {
                (void) asprintf(&buf, "%s/%s/%s", ret? "":mp.mnt_mountp, cwd,
                    tmppath);
                free(cwd);
        }
        return (buf);
}

static void
ngets(char *buf, int n)
{
        int c;
        char *lp;

        for (lp = buf; ; )
                switch (c = getchar() & 0177) {
                case '\n':
                case '\r':
                        *lp = '\0';
                        (void) putchar('\n');
                        return;
                case '\b':
                case '\177':
                        if (lp > buf) {
                                lp--;
                                (void) putchar('\b');
                                (void) putchar(' ');
                                (void) putchar('\b');
                        }
                        break;
                case 'r'&037: {
                        char *p;

                        (void) putchar('\n');
                        for (p = buf; p < lp; ++p)
                                (void) putchar(*p);
                        break;
                }
                case 'u'&037:
                case 'w'&037:
                        lp = buf;
                        (void) putchar('\n');
                        break;
                default:
                        if ((n < 1) || ((lp - buf) < n - 1)) {
                                *lp++ = c;
                                (void) putchar(c);
                        }
                }
        /*NOTREACHED*/
}

static int
fgetstr(char *buf, int size, int fd)
{
        char c;
        int err, len;

        size--;                 /* leave space for terminator */
        len = 0;
        while (size != 0) {
                err = read(fd, &c, sizeof (c));
                if (err < 0)                    /* read error */
                        return (-1);

                if (err == 0) { /* EOF */
                        if (len == 0)
                                return (-1);    /* nothing to read */
                        break;
                }
                if ((c == '\r') || (c == '\n')) /* line terminators */
                        break;
                *buf++ = c;                     /* keep char */
                size--;
                len++;
        }
        *buf = 0;
        return (len);
}

static char *
unargv(int argc, char *argv[])
{
        size_t hlong;
        int i;
        char *cp;

        for (i = 0, hlong = 0; i < argc; i++)
                hlong += strlen(argv[i]) + 2;

        if (hlong == 0)
                return (NULL);

        cp = malloc(hlong);
        cp[0] = 0;
        for (i = 0; i < argc; i++) {
                (void) strcat(cp, argv[i]);
                if (i < (argc - 1))
                        (void) strcat(cp, " ");
        }

        return (cp);
}

/*
 * Help is read from a formatted text file.
 *
 * Entries in the file are formatted as:
 * # Ttopic [Ssubtopic] Ddescription
 * help
 * text
 * here
 * #
 *
 * Note that for code simplicity's sake, the above format must be followed
 * exactly.
 *
 * Subtopic entries must immediately follow the topic (this is used to
 * produce the listing of subtopics).
 *
 * If no argument(s) are supplied by the user, the help for 'help' is displayed.
 */
static int
help_getnext(int fd, char **topic, char **subtopic, char **desc)
{
        char line[81], *cp, *ep;

        *topic = *subtopic = *desc = NULL;
        for (;;) {
                if (fgetstr(line, 80, fd) < 0)
                        return (0);

                if (strlen(line) < 3 || line[0] != '#' || line[1] != ' ')
                        continue;

                *topic = *subtopic = *desc = NULL;
                cp = line + 2;
                while (cp != NULL && *cp != 0) {
                        ep = strchr(cp, ' ');
                        if (*cp == 'T' && *topic == NULL) {
                                if (ep != NULL)
                                        *ep++ = 0;
                                *topic = strdup(cp + 1);
                        } else if (*cp == 'S' && *subtopic == NULL) {
                                if (ep != NULL)
                                        *ep++ = 0;
                                *subtopic = strdup(cp + 1);
                        } else if (*cp == 'D') {
                                *desc = strdup(cp + 1);
                                ep = NULL;
                        }
                        cp = ep;
                }
                if (*topic == NULL) {
                        free(*subtopic);
                        free(*desc);
                        continue;
                }
                return (1);
        }
}

static int
help_emitsummary(char *topic, char *subtopic, char *desc)
{
        int i;

        (void) pager_output("    ");
        (void) pager_output(topic);
        i = strlen(topic);
        if (subtopic != NULL) {
                (void) pager_output(" ");
                (void) pager_output(subtopic);
                i += strlen(subtopic) + 1;
        }
        if (desc != NULL) {
                do {
                        (void) pager_output(" ");
                } while (i++ < 30);
                (void) pager_output(desc);
        }
        return (pager_output("\n"));
}

COMMAND_SET(help, "help", "detailed help", command_help);

static int
command_help(int argc, char *argv[])
{
        char buf[81];   /* XXX buffer size? */
        int hfd, matched, doindex;
        char *topic, *subtopic, *t, *s, *d;

        /* page the help text from our load path */
        (void) snprintf(buf, sizeof (buf), "/boot/loader.help");
        if ((hfd = open(buf, O_RDONLY)) < 0) {
                printf("Verbose help not available, "
                    "use '?' to list commands\n");
                return (CMD_OK);
        }

        /* pick up request from arguments */
        topic = subtopic = NULL;
        switch (argc) {
        case 3:
                subtopic = strdup(argv[2]);
                /* FALLTHROUGH */
        case 2:
                topic = strdup(argv[1]);
        break;
        case 1:
                topic = strdup("help");
        break;
        default:
                command_errmsg = "usage is 'help <topic> [<subtopic>]";
                (void) close(hfd);
                return (CMD_ERROR);
        }

        /* magic "index" keyword */
        doindex = strcmp(topic, "index") == 0;
        matched = doindex;

        /* Scan the helpfile looking for help matching the request */
        pager_open();
        while (help_getnext(hfd, &t, &s, &d)) {
                if (doindex) {          /* dink around formatting */
                        if (help_emitsummary(t, s, d))
                                break;

                } else if (strcmp(topic, t)) {
                        /* topic mismatch */
                        /* nothing more on this topic, stop scanning */
                        if (matched)
                                break;
                } else {
                        /* topic matched */
                        matched = 1;
                        if ((subtopic == NULL && s == NULL) ||
                            (subtopic != NULL && s != NULL &&
                            strcmp(subtopic, s) == 0)) {
                                /* exact match, print text */
                                while (fgetstr(buf, 80, hfd) >= 0 &&
                                    buf[0] != '#') {
                                        if (pager_output(buf))
                                                break;
                                        if (pager_output("\n"))
                                                break;
                                }
                        } else if (subtopic == NULL && s != NULL) {
                                /* topic match, list subtopics */
                                if (help_emitsummary(t, s, d))
                                        break;
                        }
                }
                free(t);
                free(s);
                free(d);
                t = s = d = NULL;
        }
        free(t);
        free(s);
        free(d);
        pager_close();
        (void) close(hfd);
        if (!matched) {
                (void) snprintf(command_errbuf, sizeof (command_errbuf),
                    "no help available for '%s'", topic);
                free(topic);
                free(subtopic);
                return (CMD_ERROR);
        }
        free(topic);
        free(subtopic);
        return (CMD_OK);
}

COMMAND_SET(commandlist, "?", "list commands", command_commandlist);

static int
command_commandlist(int argc __unused, char *argv[] __unused)
{
        struct bootblk_command **cmdp;
        int res;
        char name[20];

        res = 0;
        pager_open();
        res = pager_output("Available commands:\n");
        SET_FOREACH(cmdp, Xcommand_set) {
                if (res)
                        break;
                if ((*cmdp)->c_name != NULL && (*cmdp)->c_desc != NULL) {
                        (void) snprintf(name, sizeof (name), "  %-15s  ",
                            (*cmdp)->c_name);
                        (void) pager_output(name);
                        (void) pager_output((*cmdp)->c_desc);
                        res = pager_output("\n");
                }
        }
        pager_close();
        return (CMD_OK);
}

/*
 * XXX set/show should become set/echo if we have variable
 * substitution happening.
 */
COMMAND_SET(show, "show", "show variable(s)", command_show);
COMMAND_SET(printenv, "printenv", "show variable(s)", command_show);

static int
command_show(int argc, char *argv[])
{
        char **ev;
        char *cp;

        if (argc < 2) {
                /*
                 * With no arguments, print everything.
                 */
                pager_open();
                for (ev = _environ; *ev != NULL; ev++) {
                        (void) pager_output(*ev);
                        cp = getenv(*ev);
                        if (cp != NULL) {
                                (void) pager_output("=");
                                (void) pager_output(cp);
                        }
                        if (pager_output("\n"))
                                break;
                }
                pager_close();
        } else {
                if ((cp = getenv(argv[1])) != NULL) {
                        printf("%s\n", cp);
                } else {
                        (void) snprintf(command_errbuf, sizeof (command_errbuf),
                            "variable '%s' not found", argv[1]);
                        return (CMD_ERROR);
                }
        }
        return (CMD_OK);
}

COMMAND_SET(set, "set", "set a variable", command_set);
static int
command_set(int argc, char *argv[])
{
        int     err;
        char    *value, *copy;

        if (argc != 2) {
                command_errmsg = "wrong number of arguments";
                return (CMD_ERROR);
        } else {
                copy = strdup(argv[1]);
                if (copy == NULL) {
                        command_errmsg = strerror(errno);
                        return (CMD_ERROR);
                }
                if ((value = strchr(copy, '=')) != NULL)
                        *(value++) = 0;
                else
                        value = "";
                if ((err = setenv(copy, value, 1)) != 0) {
                        free(copy);
                        command_errmsg = strerror(errno);
                        return (CMD_ERROR);
                }
                free(copy);
        }
        return (CMD_OK);
}

COMMAND_SET(setprop, "setprop", "set a variable", command_setprop);
static int
command_setprop(int argc, char *argv[])
{
        int err;

        if (argc != 3) {
                command_errmsg = "wrong number of arguments";
                return (CMD_ERROR);
        } else {
                if ((err = setenv(argv[1], argv[2], 1)) != 0) {
                        command_errmsg = strerror(err);
                        return (CMD_ERROR);
                }
        }
        return (CMD_OK);
}

COMMAND_SET(unset, "unset", "unset a variable", command_unset);
static int
command_unset(int argc, char *argv[])
{
        int err;

        if (argc != 2) {
                command_errmsg = "wrong number of arguments";
                return (CMD_ERROR);
        } else {
                if ((err = unsetenv(argv[1])) != 0) {
                        command_errmsg = strerror(err);
                        return (CMD_ERROR);
                }
        }
        return (CMD_OK);
}

COMMAND_SET(echo, "echo", "echo arguments", command_echo);
static int
command_echo(int argc, char *argv[])
{
        char *s;
        int nl, ch;

        nl = 0;
        optind = 1;
        opterr = 1;
        while ((ch = getopt(argc, argv, "n")) != -1) {
                switch (ch) {
                case 'n':
                        nl = 1;
                break;
                case '?':
                default:
                        /* getopt has already reported an error */
                return (CMD_OK);
                }
        }
        argv += (optind);
        argc -= (optind);

        s = unargv(argc, argv);
        if (s != NULL) {
                printf("%s", s);
                free(s);
        }
        if (!nl)
                printf("\n");
        return (CMD_OK);
}

/*
 * A passable emulation of the sh(1) command of the same name.
 */
static int
ischar(void)
{
        return (1);
}

COMMAND_SET(read, "read", "read input from the terminal", command_read);
static int
command_read(int argc, char *argv[])
{
        char *prompt;
        int timeout;
        time_t when;
        char *cp;
        char *name;
        char buf[256];          /* XXX size? */
        int c;

        timeout = -1;
        prompt = NULL;
        optind = 1;
        opterr = 1;
        while ((c = getopt(argc, argv, "p:t:")) != -1) {
                switch (c) {
                case 'p':
                        prompt = optarg;
                break;
                case 't':
                        timeout = strtol(optarg, &cp, 0);
                        if (cp == optarg) {
                                (void) snprintf(command_errbuf,
                                    sizeof (command_errbuf),
                                    "bad timeout '%s'", optarg);
                                return (CMD_ERROR);
                        }
                break;
                default:
                return (CMD_OK);
                }
        }

        argv += (optind);
        argc -= (optind);
        name = (argc > 0) ? argv[0]: NULL;

        if (prompt != NULL)
                printf("%s", prompt);
        if (timeout >= 0) {
                when = time(NULL) + timeout;
                while (!ischar())
                        if (time(NULL) >= when)
                                return (CMD_OK); /* is timeout an error? */
        }

        ngets(buf, sizeof (buf));

        if (name != NULL)
                (void) setenv(name, buf, 1);
        return (CMD_OK);
}

/*
 * File pager
 */
COMMAND_SET(more, "more", "show contents of a file", command_more);
static int
command_more(int argc, char *argv[])
{
        int i;
        int res;
        char line[80];
        char *name;

        res = 0;
        pager_open();
        for (i = 1; (i < argc) && (res == 0); i++) {
                (void) snprintf(line, sizeof (line), "*** FILE %s BEGIN ***\n",
                    argv[i]);
                if (pager_output(line))
                        break;
                name = get_dev(argv[i]);
                res = page_file(name);
                free(name);
                if (!res) {
                        (void) snprintf(line, sizeof (line),
                            "*** FILE %s END ***\n", argv[i]);
                        res = pager_output(line);
                }
        }
        pager_close();

        if (res == 0)
                return (CMD_OK);
        return (CMD_ERROR);
}

static int
page_file(char *filename)
{
        int result;

        result = pager_file(filename);

        if (result == -1) {
                (void) snprintf(command_errbuf, sizeof (command_errbuf),
                    "error showing %s", filename);
        }

        return (result);
}

COMMAND_SET(ls, "ls", "list files", command_ls);
static int
command_ls(int argc, char *argv[])
{
        DIR *dir;
        int fd;
        struct stat sb;
        struct dirent *d;
        char *buf, *path;
        char lbuf[128]; /* one line */
        int result, ch;
        int verbose;

        result = CMD_OK;
        fd = -1;
        verbose = 0;
        optind = 1;
        opterr = 1;
        while ((ch = getopt(argc, argv, "l")) != -1) {
                switch (ch) {
                case 'l':
                        verbose = 1;
                break;
                case '?':
                default:
                        /* getopt has already reported an error */
                return (CMD_OK);
                }
        }
        argv += (optind - 1);
        argc -= (optind - 1);

        if (argc < 2) {
                path = "";
        } else {
                path = argv[1];
        }

        fd = ls_getdir(&path);
        if (fd == -1) {
                result = CMD_ERROR;
                goto out;
        }
        dir = fdopendir(fd);
        pager_open();
        (void) pager_output(path);
        (void) pager_output("\n");

        while ((d = readdir(dir)) != NULL) {
                if (strcmp(d->d_name, ".") && strcmp(d->d_name, "..")) {
                        /* stat the file, if possible */
                        if (path[0] == '\0') {
                                (void) asprintf(&buf, "%s", d->d_name);
                        } else {
                                (void) asprintf(&buf, "%s/%s", path, d->d_name);
                        }
                        if (buf != NULL) {
                                /* ignore return, could be symlink, etc. */
                                if (stat(buf, &sb)) {
                                        sb.st_size = 0;
                                        sb.st_mode = 0;
                                }
                                free(buf);
                        }
                        if (verbose) {
                                (void) snprintf(lbuf, sizeof (lbuf),
                                    " %c %8d %s\n",
                                    typestr[sb.st_mode >> 12],
                                    (int)sb.st_size, d->d_name);
                        } else {
                                (void) snprintf(lbuf, sizeof (lbuf),
                                    " %c  %s\n",
                                    typestr[sb.st_mode >> 12], d->d_name);
                        }
                        if (pager_output(lbuf))
                                goto out;
                }
        }
out:
        pager_close();
        if (fd != -1)
                (void) closedir(dir);
        if (path != NULL)
                free(path);
        return (result);
}

/*
 * Given (path) containing a vaguely reasonable path specification, return an fd
 * on the directory, and an allocated copy of the path to the directory.
 */
static int
ls_getdir(char **pathp)
{
        struct stat sb;
        int fd;
        char *cp, *path;

        fd = -1;

        /* one extra byte for a possible trailing slash required */
        path = malloc(strlen(*pathp) + 2);
        (void) strcpy(path, *pathp);

        /* Make sure the path is respectable to begin with */
        if ((cp = get_dev(path)) == NULL) {
                (void) snprintf(command_errbuf, sizeof (command_errbuf),
                    "bad path '%s'", path);
                goto out;
        }

        /* If there's no path on the device, assume '/' */
        if (*cp == 0)
                (void) strcat(path, "/");

        fd = open(cp, O_RDONLY);
        if (fd < 0) {
                (void) snprintf(command_errbuf, sizeof (command_errbuf),
                    "open '%s' failed: %s", path, strerror(errno));
                goto out;
        }
        if (fstat(fd, &sb) < 0) {
                (void) snprintf(command_errbuf, sizeof (command_errbuf),
                    "stat failed: %s", strerror(errno));
                goto out;
        }
        if (!S_ISDIR(sb.st_mode)) {
                (void) snprintf(command_errbuf, sizeof (command_errbuf),
                    "%s: %s", path, strerror(ENOTDIR));
                goto out;
        }

        free(cp);
        *pathp = path;
        return (fd);

out:
        free(cp);
        free(path);
        *pathp = NULL;
        if (fd != -1)
                (void) close(fd);
        return (-1);
}

COMMAND_SET(include, "include", "read commands from a file", command_include);
static int
command_include(int argc, char *argv[])
{
        int i;
        int res;
        char **argvbuf;

        /*
         * Since argv is static, we need to save it here.
         */
        argvbuf = (char **)calloc(argc, sizeof (char *));
        for (i = 0; i < argc; i++)
                argvbuf[i] = strdup(argv[i]);

        res = CMD_OK;
        for (i = 1; (i < argc) && (res == CMD_OK); i++)
                res = include(argvbuf[i]);

        for (i = 0; i < argc; i++)
                free(argvbuf[i]);
        free(argvbuf);

        return (res);
}

/*
 * Header prepended to each line. The text immediately follows the header.
 * We try to make this short in order to save memory -- the loader has
 * limited memory available, and some of the forth files are very long.
 */
struct includeline
{
        struct includeline *next;
        int line;
        char text[];
};

int
include(const char *filename)
{
        struct includeline *script, *se, *sp;
        int res = CMD_OK;
        int prevsrcid, fd, line;
        char *cp, input[256]; /* big enough? */
        char *path;

        path = get_dev(filename);
        if (((fd = open(path, O_RDONLY)) == -1)) {
                (void) snprintf(command_errbuf, sizeof (command_errbuf),
                    "can't open '%s': %s", filename,
                    strerror(errno));
                free(path);
                return (CMD_ERROR);
        }

        free(path);
        /*
         * Read the script into memory.
         */
        script = se = NULL;
        line = 0;

        while (fgetstr(input, sizeof (input), fd) >= 0) {
                line++;
                cp = input;
                /* Allocate script line structure and copy line, flags */
                if (*cp == '\0')
                        continue;       /* ignore empty line, save memory */
                if (cp[0] == '\\' && cp[1] == ' ')
                        continue;       /* ignore comment */

                sp = malloc(sizeof (struct includeline) + strlen(cp) + 1);
                /*
                 * On malloc failure (it happens!), free as much as possible
                 * and exit
                 */
                if (sp == NULL) {
                        while (script != NULL) {
                                se = script;
                                script = script->next;
                                free(se);
                        }
                        (void) snprintf(command_errbuf, sizeof (command_errbuf),
                            "file '%s' line %d: memory allocation "
                            "failure - aborting", filename, line);
                        return (CMD_ERROR);
                }
                (void) strcpy(sp->text, cp);
                sp->line = line;
                sp->next = NULL;

                if (script == NULL) {
                        script = sp;
                } else {
                        se->next = sp;
                }
                se = sp;
        }
        (void) close(fd);

        /*
         * Execute the script
         */

        prevsrcid = bf_vm->sourceId.i;
        bf_vm->sourceId.i = fd+1;       /* 0 is user input device */

        res = CMD_OK;

        for (sp = script; sp != NULL; sp = sp->next) {
                res = bf_run(sp->text);
                if (res != FICL_VM_STATUS_OUT_OF_TEXT) {
                        (void) snprintf(command_errbuf, sizeof (command_errbuf),
                            "Error while including %s, in the line %d:\n%s",
                            filename, sp->line, sp->text);
                        res = CMD_ERROR;
                        break;
                } else
                        res = CMD_OK;
        }

        bf_vm->sourceId.i = -1;
        (void) bf_run("");
        bf_vm->sourceId.i = prevsrcid;

        while (script != NULL) {
                se = script;
                script = script->next;
                free(se);
        }

        return (res);
}

COMMAND_SET(boot, "boot", "boot a file or loaded kernel", command_boot);
static int
command_boot(int argc, char *argv[])
{
        return (CMD_OK);
}

COMMAND_SET(autoboot, "autoboot", "boot automatically after a delay",
    command_autoboot);
static int
command_autoboot(int argc, char *argv[])
{
        return (CMD_OK);
}

static void
moduledir_rebuild(void)
{
        struct moduledir *mdp, *mtmp;
        const char *path, *cp, *ep;
        int cplen;

        path = getenv("module_path");
        if (path == NULL)
                path = default_searchpath;
        /*
         * Rebuild list of module directories if it changed
         */
        STAILQ_FOREACH(mdp, &moduledir_list, d_link)
                mdp->d_flags |= MDIR_REMOVED;

        for (ep = path; *ep != 0;  ep++) {
                cp = ep;
                for (; *ep != 0 && *ep != ';'; ep++)
                        ;
                /*
                 * Ignore trailing slashes
                 */
                for (cplen = ep - cp; cplen > 1 && cp[cplen - 1] == '/';
                    cplen--)
                        ;
                STAILQ_FOREACH(mdp, &moduledir_list, d_link) {
                        if (strlen(mdp->d_path) != cplen ||
                            bcmp(cp, mdp->d_path, cplen) != 0)
                                continue;
                        mdp->d_flags &= ~MDIR_REMOVED;
                        break;
                }
                if (mdp == NULL) {
                        mdp = malloc(sizeof (*mdp) + cplen + 1);
                        if (mdp == NULL)
                                return;
                        mdp->d_path = (char *)(mdp + 1);
                        bcopy(cp, mdp->d_path, cplen);
                        mdp->d_path[cplen] = 0;
                        mdp->d_hints = NULL;
                        mdp->d_flags = 0;
                        STAILQ_INSERT_TAIL(&moduledir_list, mdp, d_link);
                }
                if (*ep == 0)
                        break;
        }
        /*
         * Delete unused directories if any
         */
        mdp = STAILQ_FIRST(&moduledir_list);
        while (mdp) {
                if ((mdp->d_flags & MDIR_REMOVED) == 0) {
                        mdp = STAILQ_NEXT(mdp, d_link);
                } else {
                        if (mdp->d_hints)
                                free(mdp->d_hints);
                        mtmp = mdp;
                        mdp = STAILQ_NEXT(mdp, d_link);
                        STAILQ_REMOVE(&moduledir_list, mtmp, moduledir, d_link);
                        free(mtmp);
                }
        }
}

static char *
file_lookup(const char *path, const char *name, int namelen)
{
        struct stat st;
        char *result, *cp, *gz;
        int pathlen;

        pathlen = strlen(path);
        result = malloc(pathlen + namelen + 2);
        if (result == NULL)
                return (NULL);
        bcopy(path, result, pathlen);
        if (pathlen > 0 && result[pathlen - 1] != '/')
                result[pathlen++] = '/';
        cp = result + pathlen;
        bcopy(name, cp, namelen);
        cp += namelen;
        *cp = '\0';
        if (stat(result, &st) == 0 && S_ISREG(st.st_mode))
                return (result);
        /* also check for gz file */
        (void) asprintf(&gz, "%s.gz", result);
        if (gz != NULL) {
                int res = stat(gz, &st);
                free(gz);
                if (res == 0)
                        return (result);
        }
        free(result);
        return (NULL);
}

static char *
file_search(const char *name)
{
        struct moduledir *mdp;
        struct stat sb;
        char *result;
        int namelen;

        if (name == NULL)
                return (NULL);
        if (*name == 0)
                return (strdup(name));

        if (strchr(name, '/') != NULL) {
                char *gz;
                if (stat(name, &sb) == 0)
                        return (strdup(name));
                /* also check for gz file */
                (void) asprintf(&gz, "%s.gz", name);
                if (gz != NULL) {
                        int res = stat(gz, &sb);
                        free(gz);
                        if (res == 0)
                                return (strdup(name));
                }
                return (NULL);
        }

        moduledir_rebuild();
        result = NULL;
        namelen = strlen(name);
        STAILQ_FOREACH(mdp, &moduledir_list, d_link) {
                result = file_lookup(mdp->d_path, name, namelen);
                if (result)
                        break;
        }
        return (result);
}

COMMAND_SET(load, "load", "load a kernel or module", command_load);
static int
command_load(int argc, char *argv[])
{
        int dofile, ch;
        char *typestr = NULL;
        char *filename;
        dofile = 0;
        optind = 1;

        if (argc == 1) {
                command_errmsg = "no filename specified";
                return (CMD_ERROR);
        }

        while ((ch = getopt(argc, argv, "kt:")) != -1) {
                switch (ch) {
                case 'k':
                        break;
                case 't':
                        typestr = optarg;
                        dofile = 1;
                        break;
                case '?':
                default:
                        return (CMD_OK);
                }
        }
        argv += (optind - 1);
        argc -= (optind - 1);
        if (dofile) {
                if ((typestr == NULL) || (*typestr == 0)) {
                        command_errmsg = "invalid load type";
                        return (CMD_ERROR);
                }
#if 0
                return (file_loadraw(argv[1], typestr, argc - 2, argv + 2, 1)
                    ? CMD_OK : CMD_ERROR);
#endif
                return (CMD_OK);
        }

        filename = file_search(argv[1]);
        if (filename == NULL) {
                (void) snprintf(command_errbuf, sizeof (command_errbuf),
                    "can't find '%s'", argv[1]);
                return (CMD_ERROR);
        }
        (void) setenv("kernelname", filename, 1);

        return (CMD_OK);
}

COMMAND_SET(unload, "unload", "unload all modules", command_unload);
static int
command_unload(int argc, char *argv[])
{
        (void) unsetenv("kernelname");
        return (CMD_OK);
}

COMMAND_SET(reboot, "reboot", "reboot the system", command_reboot);
static int
command_reboot(int argc, char *argv[])
{
        exit(0);
        return (CMD_OK);
}

COMMAND_SET(sifting, "sifting", "find words", command_sifting);
static int
command_sifting(int argc, char *argv[])
{
        if (argc != 2) {
                command_errmsg = "wrong number of arguments";
                return (CMD_ERROR);
        }
        ficlPrimitiveSiftingImpl(bf_vm, argv[1]);
        return (CMD_OK);
}

/* Only implement get and list. Ignore arguments on, off and set. */
COMMAND_SET(framebuffer, "framebuffer", "framebuffer mode management",
    command_framebuffer);
static int
command_framebuffer(int argc, char *argv[])
{
        if (fb.fd < 0) {
                printf("Framebuffer is not available.\n");
                return (CMD_OK);
        }

        if (argc == 2 && strcmp(argv[1], "get") == 0) {
                printf("\nSystem frame buffer: %s\n", fb.ident.name);
                printf("%dx%dx%d, stride=%d\n", fb.fb_width, fb.fb_height,
                    fb.fb_depth, (fb.fb_pitch << 3) / fb.fb_depth);
                return (CMD_OK);
        }
        if (argc == 2 && strcmp(argv[1], "list") == 0) {
                printf("0: %dx%dx%d\n", fb.fb_width, fb.fb_height, fb.fb_depth);
                return (CMD_OK);
        }
        if (argc == 3 && strcmp(argv[1], "set") == 0)
                return (CMD_OK);
        if (argc == 2 && strcmp(argv[1], "on") == 0)
                return (CMD_OK);
        if (argc == 2 && strcmp(argv[1], "off") == 0)
                return (CMD_OK);

        (void) snprintf(command_errbuf, sizeof (command_errbuf),
            "usage: %s get | list", argv[0]);
        return (CMD_ERROR);
}