Initial community commit

Src/external_dependencies/openmpt-trunk/soundlib/Loaders.h

@@ -0,0 +1,90 @@
+/*
+ * 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