winamp/Src/external_dependencies/openmpt-trunk/soundlib/Loaders.h
2024-09-24 14:54:57 +02:00

90 lines
3.3 KiB
C++

/*
* Loaders.h
* ---------
* Purpose: Common functions for module loaders
* Notes : (currently none)
* Authors: OpenMPT Devs
* The OpenMPT source code is released under the BSD license. Read LICENSE for more details.
*/
#pragma once
#include "openmpt/all/BuildSettings.hpp"
#include "../common/misc_util.h"
#include "../common/FileReader.h"
#include "Sndfile.h"
#include "SampleIO.h"
OPENMPT_NAMESPACE_BEGIN
// Functions to create 4-byte and 2-byte magic byte identifiers in little-endian format
// Use this together with uint32le/uint16le file members.
constexpr uint32 MagicLE(const char(&id)[5])
{
return static_cast<uint32>((static_cast<uint8>(id[3]) << 24) | (static_cast<uint8>(id[2]) << 16) | (static_cast<uint8>(id[1]) << 8) | static_cast<uint8>(id[0]));
}
constexpr uint16 MagicLE(const char(&id)[3])
{
return static_cast<uint16>((static_cast<uint8>(id[1]) << 8) | static_cast<uint8>(id[0]));
}
// Functions to create 4-byte and 2-byte magic byte identifiers in big-endian format
// Use this together with uint32be/uint16be file members.
// Note: Historically, some magic bytes in MPT-specific fields are reversed (due to the use of multi-char literals).
// Such fields turned up reversed in files, so MagicBE is used to keep them readable in the code.
constexpr uint32 MagicBE(const char(&id)[5])
{
return static_cast<uint32>((static_cast<uint8>(id[0]) << 24) | (static_cast<uint8>(id[1]) << 16) | (static_cast<uint8>(id[2]) << 8) | static_cast<uint8>(id[3]));
}
constexpr uint16 MagicBE(const char(&id)[3])
{
return static_cast<uint16>((static_cast<uint8>(id[0]) << 8) | static_cast<uint8>(id[1]));
}
// Read 'howMany' order items from an array.
// 'stopIndex' is treated as '---', 'ignoreIndex' is treated as '+++'. If the format doesn't support such indices, just pass uint16_max.
template<typename T, size_t arraySize>
bool ReadOrderFromArray(ModSequence &order, const T(&orders)[arraySize], size_t howMany = arraySize, uint16 stopIndex = uint16_max, uint16 ignoreIndex = uint16_max)
{
static_assert(mpt::is_binary_safe<T>::value);
LimitMax(howMany, arraySize);
LimitMax(howMany, MAX_ORDERS);
ORDERINDEX readEntries = static_cast<ORDERINDEX>(howMany);
order.resize(readEntries);
for(int i = 0; i < readEntries; i++)
{
PATTERNINDEX pat = static_cast<PATTERNINDEX>(orders[i]);
if(pat == stopIndex) pat = order.GetInvalidPatIndex();
else if(pat == ignoreIndex) pat = order.GetIgnoreIndex();
order.at(i) = pat;
}
return true;
}
// Read 'howMany' order items as integers with defined endianness from a file.
// 'stopIndex' is treated as '---', 'ignoreIndex' is treated as '+++'. If the format doesn't support such indices, just pass uint16_max.
template<typename T>
bool ReadOrderFromFile(ModSequence &order, FileReader &file, size_t howMany, uint16 stopIndex = uint16_max, uint16 ignoreIndex = uint16_max)
{
static_assert(mpt::is_binary_safe<T>::value);
if(!file.CanRead(howMany * sizeof(T)))
return false;
LimitMax(howMany, MAX_ORDERS);
ORDERINDEX readEntries = static_cast<ORDERINDEX>(howMany);
order.resize(readEntries);
T patF;
for(auto &pat : order)
{
file.ReadStruct(patF);
pat = static_cast<PATTERNINDEX>(patF);
if(pat == stopIndex) pat = order.GetInvalidPatIndex();
else if(pat == ignoreIndex) pat = order.GetIgnoreIndex();
}
return true;
}
OPENMPT_NAMESPACE_END