system/vulkan_enc/VulkanStreamGuest.h

// Copyright (C) 2018 The Android Open Source Project
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#pragma once

#include "android/base/files/Stream.h"
#include "android/base/files/StreamSerializing.h"

#include "goldfish_vk_private_defs.h"

#include "VulkanHandleMapping.h"

#include <memory>

class IOStream;

namespace goldfish_vk {

class VulkanStreamGuest : public android::base::Stream {
public:
    VulkanStreamGuest(IOStream* stream);
    ~VulkanStreamGuest();

    // Returns whether the connection is valid.
    bool valid();

    // General allocation function
    void alloc(void** ptrAddr, size_t bytes);

    // Utility functions to load strings or
    // string arrays in place with allocation.
    void loadStringInPlace(char** forOutput);
    void loadStringArrayInPlace(char*** forOutput);

    ssize_t read(void *buffer, size_t size) override;
    ssize_t write(const void *buffer, size_t size) override;

    // Frees everything that got alloc'ed.
    void clearPool();

    void setHandleMapping(VulkanHandleMapping* mapping);
    void unsetHandleMapping();
    VulkanHandleMapping* handleMapping() const;

    void flush();

    uint32_t getFeatureBits() const;

private:
    class Impl;
    std::unique_ptr<Impl> mImpl;
};

class VulkanCountingStream : public VulkanStreamGuest {
public:
    VulkanCountingStream();
    ~VulkanCountingStream();

    ssize_t read(void *buffer, size_t size) override;
    ssize_t write(const void *buffer, size_t size) override;

    size_t bytesWritten() const { return m_written; }
    size_t bytesRead() const { return m_read; }

    void rewind();
private:
    size_t m_written = 0;
    size_t m_read = 0;
};

} // namespace goldfish_vk