/*-
 * 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.
 *
 * $FreeBSD: src/sys/boot/common/interp.c,v 1.29 2003/08/25 23:30:41 obrien Exp $
 */

/*
 * Simple commandline interpreter, toplevel and misc.
 */

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

static void     prompt(void);
static int      iseol(char c);
static void     skipeol(int fd);

/*
 * Perform the command
 */
int
perform(int argc, char *argv[])
{
    int                         result;
    struct bootblk_command      **cmdp;
    bootblk_cmd_t               *cmd;
    const char *av0;

    if (argc < 1)
        return(CMD_OK);

    av0 = argv[0];
    if (strchr(av0, '=') != NULL)
        av0 = "local";

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

    /* search the command set for the command */
    SET_FOREACH(cmdp, Xcommand_set) {
        if (((*cmdp)->c_name != NULL) && !strcmp(av0, (*cmdp)->c_name)) {
            cmd = (*cmdp)->c_fn;
            break;
        }
    }
    if (cmd != NULL) {
        if ((*cmdp)->c_cond || CurrentCondition != 0)
                result = (cmd)(argc, argv);
        else
                result = CMD_OK;
    } else {
        command_errmsg = "unknown command";
    }
    return(result);
}

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

    /*
     * We may be booting from the boot partition, or we may be booting
     * from the root partition with a /boot sub-directory.  If the latter
     * chdir into /boot.  Ignore any error.  Only rel_open() uses the chdir
     * info.
     */
    chdir("/boot");
    setenv("base", DirBase, 1);

    /*
     * Read our default configuration
     */
    if (include("dloader.rc") != CMD_OK)
        include("boot.conf");

    /*
     * Re-evaluate base after dloader.rc may have changed currdev.
     * When loader.efi lives on the ESP and dloader.rc redirects
     * currdev to the real boot partition, the initial chdir("/boot")
     * resolved against the ESP.  Now that currdev points to the
     * correct device, re-resolve so paths work.
     */
    chdir("/boot");
    setenv("base", DirBase, 1);

    printf("\n");
    /*
     * Before interacting, we might want to autoboot.
     */
    autoboot_maybe();

    dloader_init_cmds();

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

    for (;;) {
        input[0] = '\0';
        prompt();
        ngets(input, sizeof(input));
        if (!parse(&argc, &argv, input)) {
            if (perform(argc, argv))
                printf("%s: %s\n", argv[0], command_errmsg);
            free(argv);
        } else {
            printf("parse error\n");
        }
    }
}

/*
 * 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", "run commands from 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 = include(argvbuf[i]);

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

    return(res);
}

COMMAND_SET(optinclude, "optinclude",
            "run commands from file; ignore exit status",
            command_optinclude);

static int
command_optinclude(int argc, char *argv[])
{
    int         i;
    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]);

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

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

    return(CMD_OK);
}

struct includeline
{
    char                *text;
    int                 flags;
    int                 line;
#define SL_QUIET        (1<<0)
#define SL_IGNOREERR    (1<<1)
    struct includeline  *next;
};

int
include(const char *filename)
{
    struct includeline  *script, *se, *sp;
    char                input[1024];                    /* big enough? */
    int                 argc,res;
    char                **argv, *cp;
    int                 fd, flags, line;

    if (((fd = rel_open(filename, NULL, O_RDONLY)) == -1)) {
        command_errmsg = command_errbuf;
        snprintf(command_errbuf, sizeof(command_errbuf),
            "cannot find \"%s\"", filename);
        return(CMD_ERROR);
    }

    /*
     * Read the script into memory.
     */
    script = se = NULL;
    line = 0;

    while (fgets(input, sizeof(input), fd) != NULL) {
        line++;
        flags = 0;
        if(strlen(input) == sizeof(input) - 1 &&
            !iseol(input[sizeof(input) - 2])) {
            printf("WARNING: %s: %s: Line too long: truncating; have:\n",
                __func__, filename);
            printf("%s\n", input);
            skipeol(fd);
        }
        /* Discard comments */
        if (strncmp(input+strspn(input, " "), "\\ ", 2) == 0)
            continue;
        cp = input;
        /* Echo? */
        if (input[0] == '@') {
            cp++;
            flags |= SL_QUIET;
        }
        /* Error OK? */
        if (input[0] == '-') {
            cp++;
            flags |= SL_IGNOREERR;
        }
        /* Allocate script line structure and copy line, flags */
        sp = malloc(sizeof(struct includeline) + strlen(cp) + 1);
        sp->text = (char *)sp + sizeof(struct includeline);
        strcpy(sp->text, cp);
        sp->flags = flags;
        sp->line = line;
        sp->next = NULL;

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

    /*
     * Execute the script
     */
    argv = NULL;
    res = CMD_OK;
    for (sp = script; sp != NULL; sp = sp->next) {

#if 0
        /* print if not being quiet */
        if (!(sp->flags & SL_QUIET)) {
            prompt();
            printf("%s\n", sp->text);
        }
#endif

        /* Parse the command */
        if (!parse(&argc, &argv, sp->text)) {
            if ((argc > 0) && (perform(argc, argv) != 0)) {
                /* normal command */
                printf("%s: %s\n", argv[0], command_errmsg);
                if (!(sp->flags & SL_IGNOREERR)) {
                    res=CMD_ERROR;
                    break;
                }
            }
            free(argv);
            argv = NULL;
        } else {
            printf("%s line %d: parse error\n", filename, sp->line);
            res=CMD_ERROR;
            break;
        }
    }
    if (argv != NULL)
        free(argv);
    while(script != NULL) {
        se = script;
        script = script->next;
        free(se);
    }
    return(res);
}

/*
 * Emit the current prompt; use the same syntax as the parser
 * for embedding environment variables.
 */
static void
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 int
iseol(char c)
{
    return(c == '\n' || c == '\r');
}

static void
skipeol(int fd)
{
    char c;

    while (read(fd, &c, 1) == 1) {
        if (iseol(c))
            break;
    }
}