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93 lines
1.9 KiB
C++
93 lines
1.9 KiB
C++
// Copyright 2013 Dolphin Emulator Project
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// Licensed under GPLv2
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// Refer to the license.txt file included.
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#include <algorithm>
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#include <cmath>
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#include "Blob.h"
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#include "CISOBlob.h"
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namespace DiscIO
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{
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static const char CISO_MAGIC[] = "CISO";
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CISOFileReader::CISOFileReader(std::FILE* file)
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: m_file(file)
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{
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m_size = m_file.GetSize();
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CISOHeader header;
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m_file.ReadArray(&header, 1);
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m_block_size = header.block_size;
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MapType count = 0;
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for (u32 idx = 0; idx < CISO_MAP_SIZE; idx++)
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m_ciso_map[idx] = (1 == header.map[idx]) ? count++ : UNUSED_BLOCK_ID;
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}
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CISOFileReader* CISOFileReader::Create(const char* filename)
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{
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if (IsCISOBlob(filename))
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{
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File::IOFile f(filename, "rb");
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return new CISOFileReader(f.ReleaseHandle());
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}
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else
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return NULL;
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}
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u64 CISOFileReader::GetDataSize() const
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{
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return GetRawSize();
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}
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u64 CISOFileReader::GetRawSize() const
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{
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return m_size;
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}
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bool CISOFileReader::Read(u64 offset, u64 nbytes, u8* out_ptr)
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{
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while (nbytes != 0)
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{
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auto const block = offset / m_block_size;
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auto const data_offset = offset % m_block_size;
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auto const bytes_to_read = std::min(m_block_size - data_offset, nbytes);
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if (block < CISO_MAP_SIZE && UNUSED_BLOCK_ID != m_ciso_map[block])
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{
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// calculate the base address
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auto const file_off = CISO_HEADER_SIZE + m_ciso_map[block] * m_block_size + data_offset;
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if (!(m_file.Seek(file_off, SEEK_SET) && m_file.ReadArray(out_ptr, bytes_to_read)))
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return false;
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out_ptr += bytes_to_read;
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offset += bytes_to_read;
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nbytes -= bytes_to_read;
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}
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else
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{
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std::fill_n(out_ptr, bytes_to_read, 0);
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out_ptr += bytes_to_read;
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offset += bytes_to_read;
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nbytes -= bytes_to_read;
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}
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}
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return true;
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}
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bool IsCISOBlob(const char* filename)
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{
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File::IOFile f(filename, "rb");
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CISOHeader header;
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return (f.ReadArray(&header, 1) &&
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std::equal(header.magic, header.magic + sizeof(header.magic), CISO_MAGIC));
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}
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} // namespace
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