citra/src/core/hle/kernel/session.h
2015-06-28 00:36:54 +01:00

117 lines
3.9 KiB
C++

// Copyright 2014 Citra Emulator Project
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.
#pragma once
#include <string>
#include "common/assert.h"
#include "common/common_types.h"
#include "core/hle/kernel/kernel.h"
#include "core/hle/kernel/thread.h"
#include "core/hle/result.h"
#include "core/memory.h"
namespace IPC {
inline u32 MakeHeader(u16 command_id, unsigned int regular_params, unsigned int translate_params) {
return ((u32)command_id << 16) | (((u32)regular_params & 0x3F) << 6) | (((u32)translate_params & 0x3F) << 0);
}
inline u32 MoveHandleDesc(unsigned int num_handles = 1) {
return 0x0 | ((num_handles - 1) << 26);
}
inline u32 CopyHandleDesc(unsigned int num_handles = 1) {
return 0x10 | ((num_handles - 1) << 26);
}
inline u32 CallingPidDesc() {
return 0x20;
}
inline u32 StaticBufferDesc(u32 size, unsigned int buffer_id) {
return 0x2 | (size << 14) | ((buffer_id & 0xF) << 10);
}
enum MappedBufferPermissions {
R = 2,
W = 4,
RW = R | W,
};
inline u32 MappedBufferDesc(u32 size, MappedBufferPermissions perms) {
return 0x8 | (size << 4) | (u32)perms;
}
}
namespace Kernel {
static const int kCommandHeaderOffset = 0x80; ///< Offset into command buffer of header
/**
* Returns a pointer to the command buffer in the current thread's TLS
* TODO(Subv): This is not entirely correct, the command buffer should be copied from
* the thread's TLS to an intermediate buffer in kernel memory, and then copied again to
* the service handler process' memory.
* @param offset Optional offset into command buffer
* @return Pointer to command buffer
*/
inline static u32* GetCommandBuffer(const int offset = 0) {
return (u32*)Memory::GetPointer(GetCurrentThread()->GetTLSAddress() + kCommandHeaderOffset + offset);
}
/**
* Kernel object representing the client endpoint of an IPC session. Sessions are the basic CTR-OS
* primitive for communication between different processes, and are used to implement service calls
* to the various system services.
*
* To make a service call, the client must write the command header and parameters to the buffer
* located at offset 0x80 of the TLS (Thread-Local Storage) area, then execute a SendSyncRequest
* SVC call with its Session handle. The kernel will read the command header, using it to marshall
* the parameters to the process at the server endpoint of the session. After the server replies to
* the request, the response is marshalled back to the caller's TLS buffer and control is
* transferred back to it.
*
* In Citra, only the client endpoint is currently implemented and only HLE calls, where the IPC
* request is answered by C++ code in the emulator, are supported. When SendSyncRequest is called
* with the session handle, this class's SyncRequest method is called, which should read the TLS
* buffer and emulate the call accordingly. Since the code can directly read the emulated memory,
* no parameter marshalling is done.
*
* In the long term, this should be turned into the full-fledged IPC mechanism implemented by
* CTR-OS so that IPC calls can be optionally handled by the real implementations of processes, as
* opposed to HLE simulations.
*/
class Session : public WaitObject {
public:
Session();
~Session() override;
std::string GetTypeName() const override { return "Session"; }
static const HandleType HANDLE_TYPE = HandleType::Session;
HandleType GetHandleType() const override { return HANDLE_TYPE; }
/**
* Handles a synchronous call to this session using HLE emulation. Emulated <-> emulated calls
* aren't supported yet.
*/
virtual ResultVal<bool> SyncRequest() = 0;
// TODO(bunnei): These functions exist to satisfy a hardware test with a Session object
// passed into WaitSynchronization. Figure out the meaning of them.
bool ShouldWait() override {
return true;
}
void Acquire() override {
ASSERT_MSG(!ShouldWait(), "object unavailable!");
}
};
}