akmenu-next/arm9/source/gbanes.cpp

/*
    gbanes.cpp
    Copyright (C) 2008-2009 somebody
    Copyright (C) 2009 yellow wood goblin

    SPDX-License-Identifier: GPL-3.0-or-later
*/

#include <stdio.h>
#include <string.h>
#include "gba_nes_patch_bin.h"
#include "gbapatcher.h"

bool CGbaPatcher::PatchNes(void) {
    bool res = false;
    u32 jump = Data()[0];
    if ((jump & 0xff000000) == 0xea000000) {
        size_t index = (jump & 0xffffff) + 2;
        if (Data()[index] == 0xe28f503c && Data()[index + 1] == 0xe8b503d3 &&
            Data()[index + 2] == 0xe129f007 && Data()[index + 3] == 0xe281deba &&
            Data()[index + 4] == 0xe129f008 && Data()[index + 5] == 0xe281debe &&
            Data()[index + 6] == 0xe129f009 && Data()[index + 7] == 0xe281dc0b &&
            Data()[index + 8] == 0xe92d0003 && Data()[index + 9] == 0xef110000 &&
            Data()[index + 10] == 0xe8bd8001) {
            res = true;
            iSaveSize = 8 * 1024;
            u32 patch = 0xea000000 | (0x3fdf5 - index);
            iWriter->Write(36 + index * 4, (u8*)&patch, sizeof(patch));
            iWriter->Write(0xff800, gba_nes_patch_bin, gba_nes_patch_bin_size);
            patch = Data()[index + 17];
            iWriter->Write(0xff840, (u8*)&patch, sizeof(patch));
            size_t index2 = (patch - 0x08000000) / 4;
            if (Data()[index2 - 1] == 0x3032) {
                patch = 0x060000f8;
                iWriter->Write(0xff86c, (u8*)&patch, sizeof(patch));
            }
        }
    }
    return res;
}