suyu/src/core/hle/kernel/shared_memory.h

// Copyright 2014 Citra Emulator Project
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.

#pragma once

#include "common/common_types.h"

#include "core/hle/kernel/kernel.h"

namespace Kernel {

/// Permissions for mapped shared memory blocks
enum class MemoryPermission : u32 {
    None             = 0,
    Read             = (1u <<  0),
    Write            = (1u <<  1),
    ReadWrite        = (Read | Write),
    Execute          = (1u <<  2),
    ReadExecute      = (Read | Execute),
    WriteExecute     = (Write | Execute),
    ReadWriteExecute = (Read | Write | Execute),
    DontCare         = (1u << 28)
};

class SharedMemory final : public Object {
public:
    /**
     * Creates a shared memory object
     * @param name Optional object name, used only for debugging purposes.
     */
    static ResultVal<SharedPtr<SharedMemory>> Create(std::string name = "Unknown");

    std::string GetTypeName() const override { return "SharedMemory"; }

    static const HandleType HANDLE_TYPE = HandleType::SharedMemory;
    HandleType GetHandleType() const override { return HANDLE_TYPE; }

    /**
     * Maps a shared memory block to an address in system memory
     * @param address Address in system memory to map shared memory block to
     * @param permissions Memory block map permissions (specified by SVC field)
     * @param other_permissions Memory block map other permissions (specified by SVC field)
     */
    ResultCode Map(VAddr address, MemoryPermission permissions, MemoryPermission other_permissions);

    /**
    * Gets a pointer to the shared memory block
    * @param offset Offset from the start of the shared memory block to get pointer
    * @return Pointer to the shared memory block from the specified offset
    */
    ResultVal<u8*> GetPointer(u32 offset = 0);

    VAddr base_address;                 ///< Address of shared memory block in RAM
    MemoryPermission permissions;       ///< Permissions of shared memory block (SVC field)
    MemoryPermission other_permissions; ///< Other permissions of shared memory block (SVC field)
    std::string name;                   ///< Name of shared memory object (optional)

private:
    SharedMemory() = default;
};

} // namespace