setbootmode by skrilax_cz

/*
    Copyright (C) 2012 Skrilax_CZ ([email protected])

    This program is free software; you can redistribute it and/or
    modify it under the terms of the GNU General Public License
    as published by the Free Software Foundation; either version 2
    of the License, or (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
    */

/* This uttility sets boot partition for A500 Bootlodaer */

#include <stdlib.h>
#include <unistd.h>
#include <stdio.h>
#include <string.h>

struct msc_message
{
    /* Boot commands:
     * FastbootMode - fastboot
     * FOTA - recovery
     */
    char boot_command[0x0C];

    /* Debug mode:
     * 00 - off
     * 01 - on
     */
    unsigned char debug_mode;

    /* Primary boot partition:
     * 00 - LNX
     * 01 - AKB
     */
    unsigned char boot_mode;
};

#define MSC_PARTITION "/dev/block/mmcblk0p5"

void print_usage()
{
    fprintf(stderr, "Usage: setbootmode [b1|b2]\n");
    fprintf(stderr, "b1 for booting primary kernel image\n");
    fprintf(stderr, "b2 for booting secondary kernel image\n");
}

int main(int argc, char** argv)
{
    struct msc_message msg;
    unsigned char boot_mode;
    FILE* f;

    if (argc < 2)
    {
        print_usage();
        return 1;
    }
    else if (!strcmp(argv[1], "b1"))
        boot_mode = 0;
    else if (!strcmp(argv[1], "b2"))
        boot_mode = 1;
    else
    {
        print_usage();
        return 1;
    }

    f = fopen(MSC_PARTITION, "rb+");
    if (f == NULL)
    {
        fprintf(stderr, "MSC partition not found.\n");
        return 1;
    }

    /* Read current msc message */
    fseek(f, 0x00, SEEK_SET);
    fread(&msg, 1, sizeof(struct msc_message), f);

    /* Set boot mode */
    msg.boot_mode = boot_mode;

    /* Write it back */
    fseek(f, 0x00, SEEK_SET);
    fwrite(&msg, 1, sizeof(struct msc_message), f);

    /* Done */
    fclose(f);

    if (boot_mode == 0)
        printf("Set to boot primary kernel image.\n");
    else if (boot_mode == 1)
        printf("Set to boot secondary kernel image.\n");

    return 0;
}