dolphin/Source/Core/DiscIO/WbfsBlob.cpp
2015-05-25 13:22:31 +02:00

196 lines
4.5 KiB
C++

// Copyright 2012 Dolphin Emulator Project
// Licensed under GPLv2+
// Refer to the license.txt file included.
#include <algorithm>
#include <cstdio>
#include <cstring>
#include <string>
#include <vector>
#include "Common/CommonTypes.h"
#include "Common/FileUtil.h"
#include "DiscIO/WbfsBlob.h"
namespace DiscIO
{
static const u64 WII_SECTOR_SIZE = 0x8000;
static const u64 WII_SECTOR_COUNT = 143432 * 2;
static const u64 WII_DISC_HEADER_SIZE = 256;
static inline u64 align(u64 value, u64 bounds)
{
return (value + (bounds - 1)) & (~(bounds - 1));
}
WbfsFileReader::WbfsFileReader(const std::string& filename)
: m_total_files(0), m_size(0), m_wlba_table(nullptr), m_good(true)
{
if (filename.length() < 4 || !OpenFiles(filename) || !ReadHeader())
{
m_good = false;
return;
}
// Grab disc info (assume slot 0, checked in ReadHeader())
m_wlba_table = new u16[m_blocks_per_disc];
m_files[0]->file.Seek(m_hd_sector_size + WII_DISC_HEADER_SIZE /*+ i * m_disc_info_size*/, SEEK_SET);
m_files[0]->file.ReadBytes(m_wlba_table, m_blocks_per_disc * sizeof(u16));
}
WbfsFileReader::~WbfsFileReader()
{
for (file_entry* entry : m_files)
delete entry;
delete[] m_wlba_table;
}
bool WbfsFileReader::OpenFiles(const std::string& filename)
{
m_total_files = 0;
while (true)
{
file_entry* new_entry = new file_entry;
// Replace last character with index (e.g. wbfs = wbf1)
std::string path = filename;
if (m_total_files != 0)
{
path[path.length() - 1] = '0' + m_total_files;
}
if (!new_entry->file.Open(path, "rb"))
{
delete new_entry;
return 0 != m_total_files;
}
new_entry->base_address = m_size;
new_entry->size = new_entry->file.GetSize();
m_size += new_entry->size;
m_total_files++;
m_files.push_back(new_entry);
}
}
bool WbfsFileReader::ReadHeader()
{
m_files[0]->file.Seek(4, SEEK_SET);
// Read hd size info
m_files[0]->file.ReadBytes(&m_hd_sector_count, 4);
m_hd_sector_count = Common::swap32(m_hd_sector_count);
m_files[0]->file.ReadBytes(&m_hd_sector_shift, 1);
m_hd_sector_size = 1ull << m_hd_sector_shift;
if (m_size != (m_hd_sector_count * m_hd_sector_size))
return false;
// Read wbfs cluster info
m_files[0]->file.ReadBytes(&m_wbfs_sector_shift, 1);
m_wbfs_sector_size = 1ull << m_wbfs_sector_shift;
m_wbfs_sector_count = m_size / m_wbfs_sector_size;
if (m_wbfs_sector_size < WII_SECTOR_SIZE)
return false;
m_blocks_per_disc = (WII_SECTOR_COUNT * WII_SECTOR_SIZE) / m_wbfs_sector_size;
m_disc_info_size = align(WII_DISC_HEADER_SIZE + m_blocks_per_disc * 2, m_hd_sector_size);
// Read disc table
m_files[0]->file.Seek(2, SEEK_CUR);
m_files[0]->file.ReadBytes(m_disc_table, 500);
if (m_disc_table[0] == 0)
return false;
return true;
}
bool WbfsFileReader::Read(u64 offset, u64 nbytes, u8* out_ptr)
{
while (nbytes)
{
u64 read_size = 0;
File::IOFile& data_file = SeekToCluster(offset, &read_size);
read_size = (read_size > nbytes) ? nbytes : read_size;
if (!data_file.ReadBytes(out_ptr, read_size))
{
data_file.Clear();
return false;
}
out_ptr += read_size;
nbytes -= read_size;
offset += read_size;
}
return true;
}
File::IOFile& WbfsFileReader::SeekToCluster(u64 offset, u64* available)
{
u64 base_cluster = (offset >> m_wbfs_sector_shift);
if (base_cluster < m_blocks_per_disc)
{
u64 cluster_address = m_wbfs_sector_size * Common::swap16(m_wlba_table[base_cluster]);
u64 cluster_offset = offset & (m_wbfs_sector_size - 1);
u64 final_address = cluster_address + cluster_offset;
for (u32 i = 0; i != m_total_files; i++)
{
if (final_address < (m_files[i]->base_address + m_files[i]->size))
{
m_files[i]->file.Seek(final_address - m_files[i]->base_address, SEEK_SET);
if (available)
{
u64 till_end_of_file = m_files[i]->size - (final_address - m_files[i]->base_address);
u64 till_end_of_sector = m_wbfs_sector_size - cluster_offset;
*available = std::min(till_end_of_file, till_end_of_sector);
}
return m_files[i]->file;
}
}
}
PanicAlert("Read beyond end of disc");
m_files[0]->file.Seek(0, SEEK_SET);
return m_files[0]->file;
}
WbfsFileReader* WbfsFileReader::Create(const std::string& filename)
{
WbfsFileReader* reader = new WbfsFileReader(filename);
if (reader->IsGood())
{
return reader;
}
else
{
delete reader;
return nullptr;
}
}
bool IsWbfsBlob(const std::string& filename)
{
File::IOFile f(filename, "rb");
u8 magic[4] = {0, 0, 0, 0};
f.ReadBytes(&magic, 4);
return (magic[0] == 'W') &&
(magic[1] == 'B') &&
(magic[2] == 'F') &&
(magic[3] == 'S');
}
} // namespace