From d13e18a8edfb6f26026acb72db426f651ab80ef2 Mon Sep 17 00:00:00 2001
From: bunnei <bunneidev@gmail.com>
Date: Thu, 11 Nov 2021 18:36:52 -0800
Subject: [PATCH] hle: nvflinger: Move implementation for Parcel to its own
 header.

---
 src/core/CMakeLists.txt                 |   1 +
 src/core/hle/service/nvflinger/parcel.h | 171 ++++++++++++++++++++++++
 2 files changed, 172 insertions(+)
 create mode 100644 src/core/hle/service/nvflinger/parcel.h

diff --git a/src/core/CMakeLists.txt b/src/core/CMakeLists.txt
index d9b94b4800..367d44cf38 100644
--- a/src/core/CMakeLists.txt
+++ b/src/core/CMakeLists.txt
@@ -543,6 +543,7 @@ add_library(core STATIC
     hle/service/nvflinger/consumer_listener.h
     hle/service/nvflinger/nvflinger.cpp
     hle/service/nvflinger/nvflinger.h
+    hle/service/nvflinger/parcel.h
     hle/service/nvflinger/pixel_format.h
     hle/service/nvflinger/producer_listener.h
     hle/service/nvflinger/status.h
diff --git a/src/core/hle/service/nvflinger/parcel.h b/src/core/hle/service/nvflinger/parcel.h
new file mode 100644
index 0000000000..710964f5d9
--- /dev/null
+++ b/src/core/hle/service/nvflinger/parcel.h
@@ -0,0 +1,171 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+// Copyright 2021 yuzu Emulator Project
+
+#pragma once
+
+#include <memory>
+#include <vector>
+
+#include "common/alignment.h"
+#include "common/assert.h"
+#include "common/common_types.h"
+
+namespace android {
+
+class Parcel final {
+public:
+    static constexpr std::size_t DefaultBufferSize = 0x40;
+
+    Parcel() : buffer(DefaultBufferSize) {}
+
+    template <typename T>
+    explicit Parcel(const T& out_data) : buffer(DefaultBufferSize) {
+        Write(out_data);
+    }
+
+    explicit Parcel(std::vector<u8> in_data) : buffer(std::move(in_data)) {
+        DeserializeHeader();
+        [[maybe_unused]] const std::u16string token = ReadInterfaceToken();
+    }
+
+    template <typename T>
+    void Read(T& val) {
+        static_assert(std::is_trivially_copyable_v<T>, "T must be trivially copyable.");
+        ASSERT(read_index + sizeof(T) <= buffer.size());
+
+        std::memcpy(&val, buffer.data() + read_index, sizeof(T));
+        read_index += sizeof(T);
+        read_index = Common::AlignUp(read_index, 4);
+    }
+
+    template <typename T>
+    T Read() {
+        T val;
+        Read(val);
+        return val;
+    }
+
+    template <typename T>
+    void ReadFlattened(T& val) {
+        const auto flattened_size = Read<s64>();
+        ASSERT(sizeof(T) == flattened_size);
+        Read(val);
+    }
+
+    template <typename T>
+    T ReadFlattened() {
+        T val;
+        ReadFlattened(val);
+        return val;
+    }
+
+    template <typename T>
+    T ReadUnaligned() {
+        static_assert(std::is_trivially_copyable_v<T>, "T must be trivially copyable.");
+        ASSERT(read_index + sizeof(T) <= buffer.size());
+
+        T val;
+        std::memcpy(&val, buffer.data() + read_index, sizeof(T));
+        read_index += sizeof(T);
+        return val;
+    }
+
+    template <typename T>
+    const std::shared_ptr<T> ReadObject() {
+        static_assert(std::is_trivially_copyable_v<T>, "T must be trivially copyable.");
+
+        const auto is_valid{Read<bool>()};
+
+        if (is_valid) {
+            auto result = std::make_shared<T>();
+            ReadFlattened(*result);
+            return result;
+        }
+
+        return {};
+    }
+
+    std::u16string ReadInterfaceToken() {
+        [[maybe_unused]] const u32 unknown = Read<u32>();
+        const u32 length = Read<u32>();
+
+        std::u16string token{};
+
+        for (u32 ch = 0; ch < length + 1; ++ch) {
+            token.push_back(ReadUnaligned<u16>());
+        }
+
+        read_index = Common::AlignUp(read_index, 4);
+
+        return token;
+    }
+
+    template <typename T>
+    void Write(const T& val) {
+        static_assert(std::is_trivially_copyable_v<T>, "T must be trivially copyable.");
+
+        if (buffer.size() < write_index + sizeof(T)) {
+            buffer.resize(buffer.size() + sizeof(T) + DefaultBufferSize);
+        }
+
+        std::memcpy(buffer.data() + write_index, &val, sizeof(T));
+        write_index += sizeof(T);
+        write_index = Common::AlignUp(write_index, 4);
+    }
+
+    template <typename T>
+    void WriteObject(const T* ptr) {
+        static_assert(std::is_trivially_copyable_v<T>, "T must be trivially copyable.");
+
+        if (!ptr) {
+            Write<u32>(0);
+            return;
+        }
+
+        Write<u32>(1);
+        Write<s64>(sizeof(T));
+        Write(*ptr);
+    }
+
+    template <typename T>
+    void WriteObject(const std::shared_ptr<T> ptr) {
+        WriteObject(ptr.get());
+    }
+
+    void DeserializeHeader() {
+        ASSERT(buffer.size() > sizeof(Header));
+
+        Header header{};
+        std::memcpy(&header, buffer.data(), sizeof(Header));
+
+        read_index = header.data_offset;
+    }
+
+    std::vector<u8> Serialize() const {
+        ASSERT(read_index == 0);
+
+        Header header{};
+        header.data_size = static_cast<u32>(write_index - sizeof(Header));
+        header.data_offset = sizeof(Header);
+        header.objects_size = 4;
+        header.objects_offset = static_cast<u32>(sizeof(Header) + header.data_size);
+        std::memcpy(buffer.data(), &header, sizeof(Header));
+
+        return buffer;
+    }
+
+private:
+    struct Header {
+        u32 data_size;
+        u32 data_offset;
+        u32 objects_size;
+        u32 objects_offset;
+    };
+    static_assert(sizeof(Header) == 16, "ParcelHeader has wrong size");
+
+    mutable std::vector<u8> buffer;
+    std::size_t read_index = 0;
+    std::size_t write_index = sizeof(Header);
+};
+
+} // namespace android