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Add ROM Header CRC Recalculation 

Add ROM Header CRC Recalculation
This commit is contained in:
Nekokabu 2015-06-15 22:08:07 +09:00
parent edb8d5288c
commit a55e567b8b
1 changed files with 79 additions and 0 deletions
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79
Source/Project64/N64 System/N64 Rom Class.cpp
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@ -256,6 +256,78 @@ void CN64Rom::CalculateCicChip()
}
void CN64Rom::CalculateRomCrc()
{
DWORD t0, t1, t2, t3, t4, t5, t7;
DWORD a0, a1, a2, a3;
DWORD s0;
DWORD v0, v1;
DWORD OldProtect;
VirtualProtect(m_ROMImage, m_RomFileSize, PAGE_READWRITE, &OldProtect);
switch (m_CicChip) {
case CIC_NUS_6101:
case CIC_NUS_6102:
{
v1 = 0;
t0 = 0;
t5 = 0x20;
v0 = 0xF8CA4DDB + 1; // 0xFFFFFFFF & (0x3F * 0x5D588B65)
a3 = v0;
t2 = v0;
t3 = v0;
s0 = v0;
a2 = v0;
t4 = v0;
for (t0 = 0, t1 = 0x1000; t0 < 0x00100000; t0 += 4, t1 += 4){
v0 = *(DWORD *)(m_ROMImage + t1);
v1 = a3 + v0;
a1 = v1;
if (v1 < a3) t2 += 0x1;
v1 = v0 & 0x001F;
t7 = t5 - v1;
a0 = (v0 << v1) | (v0 >> t7);
a3 = a1;
t3 = t3 ^ v0;
s0 = s0 + a0;
if (a2 < v0){
a2 = a3 ^ v0 ^ a2;
}
else{
a2 = a2 ^ a0;
}
t4 = (v0 ^ s0) + t4;
}
a3 = a3 ^ t2 ^ t3;
s0 = s0 ^ a2 ^ t4;
*(DWORD *)(m_ROMImage + 0x10) = a3;
*(DWORD *)(m_ROMImage + 0x14) = s0;
break;
}
case CIC_NUS_6103:
case CIC_NUS_6105:
case CIC_NUS_6106:
case CIC_NUS_8303:
case CIC_NUS_DDIPL:
case CIC_UNKNOWN:
default:
break;
}
VirtualProtect(m_ROMImage, m_RomFileSize, PAGE_READONLY, &OldProtect);
}
CICChip CN64Rom::CicChipID()
{
return m_CicChip;
@ -471,6 +543,13 @@ bool CN64Rom::LoadN64Image ( const char * FileLoc, bool LoadBootCodeOnly ) {
{
SaveRomSettingID(false);
}
if (g_Settings->LoadBool(Game_CRC_Recalc))
{
//Calculate ROM Header CRC
CalculateRomCrc();
}
return true;
}