/*-
 * 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.
 */

/*
 * Simple commandline interpreter, toplevel and misc.
 *
 * XXX may be obsoleted by BootFORTH or some other, better, interpreter.
 */

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

#ifdef LOADER_VERIEXEC
#include <verify_file.h>
#endif

#define MAXARGS 20                      /* maximum number of arguments allowed */

const char * volatile   interp_identifier;

/*
 * Interactive mode
 */
void
interact(void)
{
        static char             input[256];             /* big enough? */

        TSENTER();

        /*
         * Because interp_identifier is volatile, it cannot be optimized out by
         * the compiler as it's considered an externally observable event.  This
         * prevents the compiler from optimizing out our carefully placed
         * $Interpreter:4th string that userboot may use to determine that
         * we need to switch interpreters.
         */
        interp_identifier = bootprog_interp;
        interp_preinit();
        interp_init();

        printf("\n");

        /*
         * Before interacting, we might want to autoboot.
         */
        autoboot_maybe();

        /*
         * Not autobooting, go manual
         */
        printf("\nType '?' for a list of commands, 'help' for more detailed help.\n");
        if (getenv("prompt") == NULL)
                setenv("prompt", "${interpret}", 1);
        if (getenv("interpret") == NULL)
                setenv("interpret", "OK", 1);

        for (;;) {
                input[0] = '\0';
                interp_emit_prompt();
                ngets(input, sizeof(input));
#ifdef LOADER_VERIEXEC
                /* some settings should be restritcted */
                ve_status_set(-1, VE_UNVERIFIED_OK);
#endif
                interp_run(input);
        }
}

/*
 * Read commands from a file, then execute them.
 *
 * We store the commands in memory and close the source file so that the media
 * holding it can safely go away while we are executing.
 *
 * Commands may be prefixed with '@' (so they aren't displayed) or '-' (so
 * that the script won't stop if they fail).
 */
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((u_int)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 = interp_include(argvbuf[i]);

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

        return(res);
}

/*
 * Emit the current prompt; use the same syntax as the parser
 * for embedding environment variables. Does not accept input.
 */
void
interp_emit_prompt(void)
{
        char            *pr, *p, *cp, *ev;

        if ((cp = getenv("prompt")) == NULL)
                cp = ">";
        pr = p = strdup(cp);

        while (*p != 0) {
                if ((*p == '$') && (*(p+1) == '{')) {
                        for (cp = p + 2; (*cp != 0) && (*cp != '}'); cp++)
                                ;
                        *cp = 0;
                        ev = getenv(p + 2);

                        if (ev != NULL)
                                printf("%s", ev);
                        p = cp + 1;
                        continue;
                }
                putchar(*p++);
        }
        putchar(' ');
        free(pr);
}

static struct bootblk_command *
interp_lookup_cmd(const char *cmd)
{
        struct bootblk_command  **cmdp;

        /* search the command set for the command */
        SET_FOREACH(cmdp, Xcommand_set) {
                if (((*cmdp)->c_name != NULL) && !strcmp(cmd, (*cmdp)->c_name))
                        return (*cmdp);
        }
        return (NULL);
}

/*
 * Perform a builtin command
 */
int
interp_builtin_cmd(int argc, char *argv[])
{
        int                     result;
        struct bootblk_command  *cmd;

        if (argc < 1)
                return (CMD_OK);

        /* set return defaults; a successful command will override these */
        command_errmsg = command_errbuf;
        strcpy(command_errbuf, "no error message");
        result = CMD_ERROR;

        cmd = interp_lookup_cmd(argv[0]);
        if (cmd != NULL && cmd->c_fn) {
                TSENTER2(argv[0]);
                result = cmd->c_fn(argc, argv);
                TSEXIT();
        } else {
                command_errmsg = "unknown command";
        }
        return (result);
}

/*
 * Return true if the builtin command exists
 */
bool
interp_has_builtin_cmd(const char *cmd)
{
        return (interp_lookup_cmd(cmd) != NULL);
}