dolphin/Source/Core/DiscIO/FileSystemGCWii.cpp
JosJuice c7e747d775 DiscIO: Improve IVolume::Read32 error handling
Callers can now check whether reads fail, either by checking the return
value or by setting the buffer to a known bad value and seeing if it stays
untouched. I've added error checks to FileSystemGCWii and Boot_BS2Emu,
but not to Boot since it doesn't check any of its other reads either.
2015-12-14 09:38:21 +01:00

358 lines
9.0 KiB
C++

// Copyright 2008 Dolphin Emulator Project
// Licensed under GPLv2+
// Refer to the license.txt file included.
#include <algorithm>
#include <cinttypes>
#include <cstddef>
#include <cstring>
#include <string>
#include <vector>
#include "Common/CommonTypes.h"
#include "Common/FileUtil.h"
#include "Common/MsgHandler.h"
#include "Common/StringUtil.h"
#include "Common/Logging/Log.h"
#include "DiscIO/Filesystem.h"
#include "DiscIO/FileSystemGCWii.h"
#include "DiscIO/Volume.h"
namespace DiscIO
{
CFileSystemGCWii::CFileSystemGCWii(const IVolume *_rVolume)
: IFileSystem(_rVolume)
, m_Initialized(false)
, m_Valid(false)
, m_Wii(false)
{
m_Valid = DetectFileSystem();
}
CFileSystemGCWii::~CFileSystemGCWii()
{
m_FileInfoVector.clear();
}
u64 CFileSystemGCWii::GetFileSize(const std::string& _rFullPath)
{
if (!m_Initialized)
InitFileSystem();
const SFileInfo* pFileInfo = FindFileInfo(_rFullPath);
if (pFileInfo != nullptr && !pFileInfo->IsDirectory())
return pFileInfo->m_FileSize;
return 0;
}
const std::string CFileSystemGCWii::GetFileName(u64 _Address)
{
if (!m_Initialized)
InitFileSystem();
for (auto& fileInfo : m_FileInfoVector)
{
if ((fileInfo.m_Offset <= _Address) &&
((fileInfo.m_Offset + fileInfo.m_FileSize) > _Address))
{
return fileInfo.m_FullPath;
}
}
return "";
}
u64 CFileSystemGCWii::ReadFile(const std::string& _rFullPath, u8* _pBuffer, u64 _MaxBufferSize, u64 _OffsetInFile)
{
if (!m_Initialized)
InitFileSystem();
const SFileInfo* pFileInfo = FindFileInfo(_rFullPath);
if (pFileInfo == nullptr)
return 0;
if (_OffsetInFile >= pFileInfo->m_FileSize)
return 0;
u64 read_length = std::min(_MaxBufferSize, pFileInfo->m_FileSize - _OffsetInFile);
DEBUG_LOG(DISCIO, "Reading %" PRIx64 " bytes at %" PRIx64 " from file %s. Offset: %" PRIx64 " Size: %" PRIx64,
read_length, _OffsetInFile, _rFullPath.c_str(), pFileInfo->m_Offset, pFileInfo->m_FileSize);
m_rVolume->Read(pFileInfo->m_Offset + _OffsetInFile, read_length, _pBuffer, m_Wii);
return read_length;
}
bool CFileSystemGCWii::ExportFile(const std::string& _rFullPath, const std::string& _rExportFilename)
{
if (!m_Initialized)
InitFileSystem();
const SFileInfo* pFileInfo = FindFileInfo(_rFullPath);
if (!pFileInfo)
return false;
u64 remainingSize = pFileInfo->m_FileSize;
u64 fileOffset = pFileInfo->m_Offset;
File::IOFile f(_rExportFilename, "wb");
if (!f)
return false;
bool result = true;
while (remainingSize)
{
// Limit read size to 128 MB
size_t readSize = (size_t)std::min(remainingSize, (u64)0x08000000);
std::vector<u8> buffer(readSize);
result = m_rVolume->Read(fileOffset, readSize, &buffer[0], m_Wii);
if (!result)
break;
f.WriteBytes(&buffer[0], readSize);
remainingSize -= readSize;
fileOffset += readSize;
}
return result;
}
bool CFileSystemGCWii::ExportApploader(const std::string& _rExportFolder) const
{
u32 apploader_size;
u32 trailer_size;
const u32 header_size = 0x20;
if (!m_rVolume->ReadSwapped(0x2440 + 0x14, &apploader_size, m_Wii) ||
!m_rVolume->ReadSwapped(0x2440 + 0x18, &trailer_size, m_Wii))
return false;
apploader_size += trailer_size + header_size;
DEBUG_LOG(DISCIO, "Apploader size -> %x", apploader_size);
std::vector<u8> buffer(apploader_size);
if (m_rVolume->Read(0x2440, apploader_size, buffer.data(), m_Wii))
{
std::string exportName(_rExportFolder + "/apploader.img");
File::IOFile AppFile(exportName, "wb");
if (AppFile)
{
AppFile.WriteBytes(buffer.data(), apploader_size);
return true;
}
}
return false;
}
u64 CFileSystemGCWii::GetBootDOLOffset() const
{
u32 offset = 0;
m_rVolume->ReadSwapped(0x420, &offset, m_Wii);
return static_cast<u64>(offset) << GetOffsetShift();
}
u32 CFileSystemGCWii::GetBootDOLSize(u64 dol_offset) const
{
// The dol_offset value is usually obtained by calling GetBootDOLOffset.
// If GetBootDOLOffset fails by returning 0, GetBootDOLSize should also fail.
if (dol_offset == 0)
return 0;
u32 dol_size = 0;
u32 offset = 0;
u32 size = 0;
// Iterate through the 7 code segments
for (u8 i = 0; i < 7; i++)
{
if (!m_rVolume->ReadSwapped(dol_offset + 0x00 + i * 4, &offset, m_Wii) ||
!m_rVolume->ReadSwapped(dol_offset + 0x90 + i * 4, &size, m_Wii))
return 0;
dol_size = std::max(offset + size, dol_size);
}
// Iterate through the 11 data segments
for (u8 i = 0; i < 11; i++)
{
if (!m_rVolume->ReadSwapped(dol_offset + 0x1c + i * 4, &offset, m_Wii) ||
!m_rVolume->ReadSwapped(dol_offset + 0xac + i * 4, &size, m_Wii))
return 0;
dol_size = std::max(offset + size, dol_size);
}
return dol_size;
}
bool CFileSystemGCWii::ExportDOL(const std::string& _rExportFolder) const
{
u64 DolOffset = GetBootDOLOffset();
u32 DolSize = GetBootDOLSize(DolOffset);
if (DolOffset == 0 || DolSize == 0)
return false;
std::vector<u8> buffer(DolSize);
if (m_rVolume->Read(DolOffset, DolSize, &buffer[0], m_Wii))
{
std::string exportName(_rExportFolder + "/boot.dol");
File::IOFile DolFile(exportName, "wb");
if (DolFile)
{
DolFile.WriteBytes(&buffer[0], DolSize);
return true;
}
}
return false;
}
std::string CFileSystemGCWii::GetStringFromOffset(u64 _Offset) const
{
std::string data(255, 0x00);
m_rVolume->Read(_Offset, data.size(), (u8*)&data[0], m_Wii);
data.erase(std::find(data.begin(), data.end(), 0x00), data.end());
// TODO: Should we really always use SHIFT-JIS?
// It makes some filenames in Pikmin (NTSC-U) sane, but is it correct?
return SHIFTJISToUTF8(data);
}
const std::vector<SFileInfo>& CFileSystemGCWii::GetFileList()
{
if (!m_Initialized)
InitFileSystem();
return m_FileInfoVector;
}
const SFileInfo* CFileSystemGCWii::FindFileInfo(const std::string& _rFullPath)
{
if (!m_Initialized)
InitFileSystem();
for (auto& fileInfo : m_FileInfoVector)
{
if (!strcasecmp(fileInfo.m_FullPath.c_str(), _rFullPath.c_str()))
return &fileInfo;
}
return nullptr;
}
bool CFileSystemGCWii::DetectFileSystem()
{
u32 magic_bytes;
if (m_rVolume->ReadSwapped(0x18, &magic_bytes, false) && magic_bytes == 0x5D1C9EA3)
{
m_Wii = true;
return true;
}
else if (m_rVolume->ReadSwapped(0x1c, &magic_bytes, false) && magic_bytes == 0xC2339F3D)
{
m_Wii = false;
return true;
}
return false;
}
void CFileSystemGCWii::InitFileSystem()
{
m_Initialized = true;
u32 const shift = GetOffsetShift();
// read the whole FST
u32 fst_offset_unshifted;
if (!m_rVolume->ReadSwapped(0x424, &fst_offset_unshifted, m_Wii))
return;
u64 FSTOffset = static_cast<u64>(fst_offset_unshifted) << shift;
// read all fileinfos
u32 name_offset, offset, size;
if (!m_rVolume->ReadSwapped(FSTOffset + 0x0, &name_offset, m_Wii) ||
!m_rVolume->ReadSwapped(FSTOffset + 0x4, &offset, m_Wii) ||
!m_rVolume->ReadSwapped(FSTOffset + 0x8, &size, m_Wii))
return;
SFileInfo root = { name_offset, static_cast<u64>(offset) << shift, size };
if (!root.IsDirectory())
return;
// 12 bytes (the size of a file entry) times 10 * 1024 * 1024 is 120 MiB,
// more than total RAM in a Wii. No file system should use anywhere near that much.
static const u32 ARBITRARY_FILE_SYSTEM_SIZE_LIMIT = 10 * 1024 * 1024;
if (root.m_FileSize > ARBITRARY_FILE_SYSTEM_SIZE_LIMIT)
{
// Without this check, Dolphin can crash by trying to allocate too much
// memory when loading the file systems of certain malformed disc images.
ERROR_LOG(DISCIO, "File system is abnormally large! Aborting loading");
return;
}
if (m_FileInfoVector.size())
PanicAlert("Wtf?");
u64 NameTableOffset = FSTOffset;
m_FileInfoVector.reserve((size_t)root.m_FileSize);
for (u32 i = 0; i < root.m_FileSize; i++)
{
const u64 read_offset = FSTOffset + (i * 0xC);
name_offset = 0;
m_rVolume->ReadSwapped(read_offset + 0x0, &name_offset, m_Wii);
offset = 0;
m_rVolume->ReadSwapped(read_offset + 0x4, &offset, m_Wii);
size = 0;
m_rVolume->ReadSwapped(read_offset + 0x8, &size, m_Wii);
m_FileInfoVector.emplace_back(name_offset, static_cast<u64>(offset) << shift, size);
NameTableOffset += 0xC;
}
BuildFilenames(1, m_FileInfoVector.size(), "", NameTableOffset);
}
size_t CFileSystemGCWii::BuildFilenames(const size_t _FirstIndex, const size_t _LastIndex, const std::string& _szDirectory, u64 _NameTableOffset)
{
size_t CurrentIndex = _FirstIndex;
while (CurrentIndex < _LastIndex)
{
SFileInfo& rFileInfo = m_FileInfoVector[CurrentIndex];
u64 const uOffset = _NameTableOffset + (rFileInfo.m_NameOffset & 0xFFFFFF);
std::string const offset_str { GetStringFromOffset(uOffset) };
bool const is_dir = rFileInfo.IsDirectory();
rFileInfo.m_FullPath.reserve(_szDirectory.size() + offset_str.size());
rFileInfo.m_FullPath.append(_szDirectory.data(), _szDirectory.size())
.append(offset_str.data(), offset_str.size())
.append("/", size_t(is_dir));
if (!is_dir)
{
++CurrentIndex;
continue;
}
// check next index
CurrentIndex = BuildFilenames(CurrentIndex + 1, (size_t) rFileInfo.m_FileSize, rFileInfo.m_FullPath, _NameTableOffset);
}
return CurrentIndex;
}
u32 CFileSystemGCWii::GetOffsetShift() const
{
return m_Wii ? 2 : 0;
}
} // namespace