From 78b9c64f67aa0c6c52f7da31a59e4d5512a83c8f Mon Sep 17 00:00:00 2001
From: Nekotekina <nekotekina@gmail.com>
Date: Wed, 29 Mar 2017 02:54:05 +0300
Subject: [PATCH] Simple patch engine

---
 Utilities/bin_patch.cpp       | 105 ++++++++++++++++++++++++++++++++++
 Utilities/bin_patch.h         |  37 ++++++++++++
 rpcs3/Emu/System.cpp          |   8 +++
 rpcs3/emucore.vcxproj         |   4 ++
 rpcs3/emucore.vcxproj.filters |   6 ++
 5 files changed, 160 insertions(+)
 create mode 100644 Utilities/bin_patch.cpp
 create mode 100644 Utilities/bin_patch.h

diff --git a/Utilities/bin_patch.cpp b/Utilities/bin_patch.cpp
new file mode 100644
index 0000000000..60d0a05c8a
--- /dev/null
+++ b/Utilities/bin_patch.cpp
@@ -0,0 +1,105 @@
+#include "bin_patch.h"
+#include "yaml-cpp/yaml.h"
+#include "File.h"
+#include "Config.h"
+
+template <>
+void fmt_class_string<patch_type>::format(std::string& out, u64 arg)
+{
+	format_enum(out, arg, [](patch_type value)
+	{
+		switch (value)
+		{
+		case patch_type::byte: return "byte";
+		case patch_type::le16: return "le16";
+		case patch_type::le32: return "le32";
+		case patch_type::le64: return "le64";
+		case patch_type::be16: return "be16";
+		case patch_type::be32: return "be32";
+		case patch_type::be64: return "be64";
+		}
+
+		return unknown;
+	});
+}
+
+void patch_engine::append(const std::string& patch)
+{
+	if (fs::file f{patch})
+	{
+		auto root = YAML::Load(f.to_string());
+
+		for (auto pair : root)
+		{
+			auto& name = pair.first.Scalar();
+			auto& data = m_map[name];
+			
+			for (auto patch : pair.second)
+			{
+				u64 type64 = 0;
+				cfg::try_to_enum_value(&type64, &fmt_class_string<patch_type>::format, patch[0].Scalar());
+
+				struct patch info;
+				info.type   = static_cast<patch_type>(type64);
+				info.offset = patch[1].as<u32>();
+				info.value  = patch[2].as<u64>();
+				data.emplace_back(info);
+			}
+		}
+	}
+}
+
+void patch_engine::apply(const std::string& name, u8* dst) const
+{
+	const auto found = m_map.find(name);
+
+	if (found == m_map.cend())
+	{
+		return;
+	}
+
+	// Apply modifications sequentially
+	for (const auto& p : found->second)
+	{
+		auto ptr = dst + p.offset;
+
+		switch (p.type)
+		{
+		case patch_type::byte:
+		{
+			*ptr = static_cast<u8>(p.value);
+			break;
+		}
+		case patch_type::le16:
+		{
+			*reinterpret_cast<le_t<u16, 1>*>(ptr) = static_cast<u16>(p.value);
+			break;
+		}
+		case patch_type::le32:
+		{
+			*reinterpret_cast<le_t<u32, 1>*>(ptr) = static_cast<u32>(p.value);
+			break;
+		}
+		case patch_type::le64:
+		{
+			*reinterpret_cast<le_t<u64, 1>*>(ptr) = static_cast<u64>(p.value);
+			break;
+		}
+		case patch_type::be16:
+		{
+			*reinterpret_cast<be_t<u16, 1>*>(ptr) = static_cast<u16>(p.value);
+			break;
+		}
+		case patch_type::be32:
+		{
+			*reinterpret_cast<be_t<u32, 1>*>(ptr) = static_cast<u32>(p.value);
+			break;
+		}
+		case patch_type::be64:
+		{
+			*reinterpret_cast<be_t<u64, 1>*>(ptr) = static_cast<u64>(p.value);
+			break;
+		}
+		}
+	}
+}
diff --git a/Utilities/bin_patch.h b/Utilities/bin_patch.h
new file mode 100644
index 0000000000..56704e5d52
--- /dev/null
+++ b/Utilities/bin_patch.h
@@ -0,0 +1,37 @@
+#pragma once
+
+#include "BEType.h"
+#include <vector>
+#include <string>
+#include <unordered_map>
+
+enum class patch_type
+{
+	byte,
+	le16,
+	le32,
+	le64,
+	be16,
+	be32,
+	be64,
+};
+
+class patch_engine
+{
+	struct patch
+	{
+		patch_type type;
+		u32 offset;
+		u64 value;
+	};
+
+	// Database
+	std::unordered_map<std::string, std::vector<patch>> m_map;
+
+public:
+	// Load from file
+	void append(const std::string& path);
+
+	// Apply patch
+	void apply(const std::string& name, u8* dst) const;
+};
diff --git a/rpcs3/Emu/System.cpp b/rpcs3/Emu/System.cpp
index 7bbb3e07fa..99390def52 100644
--- a/rpcs3/Emu/System.cpp
+++ b/rpcs3/Emu/System.cpp
@@ -2,6 +2,7 @@
 #include "Utilities/Config.h"
 #include "Utilities/AutoPause.h"
 #include "Utilities/event.h"
+#include "Utilities/bin_patch.h"
 #include "Emu/Memory/Memory.h"
 #include "Emu/System.h"
 
@@ -99,6 +100,9 @@ void Emulator::Init()
 	fs::create_dir(dev_hdd1 + "game/");
 	fs::create_path(dev_hdd1);
 	fs::create_path(dev_usb);
+
+	// Initialize patch engine
+	fxm::make_always<patch_engine>()->append(fs::get_config_dir() + "/patch.yml");
 }
 
 void Emulator::SetPath(const std::string& path, const std::string& elf_path)
@@ -215,6 +219,10 @@ void Emulator::Load()
 
 		LOG_NOTICE(LOADER, "Used configuration:\n%s\n", cfg::root.to_string());
 
+		// Load patches from different locations
+		fxm::check_unlocked<patch_engine>()->append(fs::get_config_dir() + "data/" + m_title_id + "/patch.yml");
+		fxm::check_unlocked<patch_engine>()->append(m_cache_path + "/patch.yml");
+
 		// Mount all devices
 		const std::string emu_dir_ = g_cfg_vfs_emulator_dir;
 		const std::string emu_dir = emu_dir_.empty() ? fs::get_config_dir() : emu_dir_;
diff --git a/rpcs3/emucore.vcxproj b/rpcs3/emucore.vcxproj
index bbe6a7943e..8d720c1a64 100644
--- a/rpcs3/emucore.vcxproj
+++ b/rpcs3/emucore.vcxproj
@@ -73,6 +73,9 @@
       <PrecompiledHeader>NotUsing</PrecompiledHeader>
     </ClCompile>
     <ClCompile Include="..\Utilities\AutoPause.cpp" />
+    <ClCompile Include="..\Utilities\bin_patch.cpp">
+      <PrecompiledHeader>NotUsing</PrecompiledHeader>
+    </ClCompile>
     <ClCompile Include="..\Utilities\cond.cpp">
       <PrecompiledHeader>NotUsing</PrecompiledHeader>
     </ClCompile>
@@ -396,6 +399,7 @@
     <ClInclude Include="..\Utilities\AtomicPtr.h" />
     <ClInclude Include="..\Utilities\AutoPause.h" />
     <ClInclude Include="..\Utilities\BEType.h" />
+    <ClInclude Include="..\Utilities\bin_patch.h" />
     <ClInclude Include="..\Utilities\BitField.h" />
     <ClInclude Include="..\Utilities\bit_set.h" />
     <ClInclude Include="..\Utilities\cfmt.h" />
diff --git a/rpcs3/emucore.vcxproj.filters b/rpcs3/emucore.vcxproj.filters
index 840db6c849..2e4bb036e3 100644
--- a/rpcs3/emucore.vcxproj.filters
+++ b/rpcs3/emucore.vcxproj.filters
@@ -908,6 +908,9 @@
     <ClCompile Include="Loader\TAR.cpp">
       <Filter>Loader</Filter>
     </ClCompile>
+    <ClCompile Include="..\Utilities\bin_patch.cpp">
+      <Filter>Utilities</Filter>
+    </ClCompile>
   </ItemGroup>
   <ItemGroup>
     <ClInclude Include="Crypto\aes.h">
@@ -1738,5 +1741,8 @@
     <ClInclude Include="Loader\TAR.h">
       <Filter>Loader</Filter>
     </ClInclude>
+    <ClInclude Include="..\Utilities\bin_patch.h">
+      <Filter>Utilities</Filter>
+    </ClInclude>
   </ItemGroup>
 </Project>
\ No newline at end of file