mirror of
https://github.com/dashpay/dash.git
synced 2024-12-26 04:22:55 +01:00
9d9d97d4fd
3e33d170cc0a8f386791777f3cc597e2bd0bf2ee Add ipc::Context and ipc::capnp::Context structs (Russell Yanofsky) Pull request description: These are currently empty structs but they will be used to pass some function and object pointers from bitcoin application code to IPC hooks that run, for example, when a remote object is created or destroyed, or a new process is created. --- This PR is part of the [process separation project](https://github.com/bitcoin/bitcoin/projects/10). The commit was first part of larger PR #10102. ACKs for top commit: ariard: Code Review ACK 3e33d170 Tree-SHA512: fd949fae5f1a973d39cb97f2745821ab2f62b98e166e53bc2801f97dcde988e18faaaaa0ffc2a82c170938b3a18078b6162fa35460e6e7c635e681b3c9e5b0a6
79 lines
3.4 KiB
C++
79 lines
3.4 KiB
C++
// Copyright (c) 2021 The Bitcoin Core developers
|
|
// Distributed under the MIT software license, see the accompanying
|
|
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
|
|
|
|
#ifndef BITCOIN_INTERFACES_IPC_H
|
|
#define BITCOIN_INTERFACES_IPC_H
|
|
|
|
#include <functional>
|
|
#include <memory>
|
|
#include <typeindex>
|
|
|
|
namespace ipc {
|
|
struct Context;
|
|
} // namespace ipc
|
|
|
|
namespace interfaces {
|
|
class Init;
|
|
|
|
//! Interface providing access to interprocess-communication (IPC)
|
|
//! functionality. The IPC implementation is responsible for establishing
|
|
//! connections between a controlling process and a process being controlled.
|
|
//! When a connection is established, the process being controlled returns an
|
|
//! interfaces::Init pointer to the controlling process, which the controlling
|
|
//! process can use to get access to other interfaces and functionality.
|
|
//!
|
|
//! When spawning a new process, the steps are:
|
|
//!
|
|
//! 1. The controlling process calls interfaces::Ipc::spawnProcess(), which
|
|
//! calls ipc::Process::spawn(), which spawns a new process and returns a
|
|
//! socketpair file descriptor for communicating with it.
|
|
//! interfaces::Ipc::spawnProcess() then calls ipc::Protocol::connect()
|
|
//! passing the socketpair descriptor, which returns a local proxy
|
|
//! interfaces::Init implementation calling remote interfaces::Init methods.
|
|
//! 2. The spawned process calls interfaces::Ipc::startSpawnProcess(), which
|
|
//! calls ipc::Process::checkSpawned() to read command line arguments and
|
|
//! determine whether it is a spawned process and what socketpair file
|
|
//! descriptor it should use. It then calls ipc::Protocol::serve() to handle
|
|
//! incoming requests from the socketpair and invoke interfaces::Init
|
|
//! interface methods, and exit when the socket is closed.
|
|
//! 3. The controlling process calls local proxy interfaces::Init object methods
|
|
//! to make other proxy objects calling other remote interfaces. It can also
|
|
//! destroy the initial interfaces::Init object to close the connection and
|
|
//! shut down the spawned process.
|
|
class Ipc
|
|
{
|
|
public:
|
|
virtual ~Ipc() = default;
|
|
|
|
//! Spawn a child process returning pointer to its Init interface.
|
|
virtual std::unique_ptr<Init> spawnProcess(const char* exe_name) = 0;
|
|
|
|
//! If this is a spawned process, block and handle requests from the parent
|
|
//! process by forwarding them to this process's Init interface, then return
|
|
//! true. If this is not a spawned child process, return false.
|
|
virtual bool startSpawnedProcess(int argc, char* argv[], int& exit_status) = 0;
|
|
|
|
//! Add cleanup callback to remote interface that will run when the
|
|
//! interface is deleted.
|
|
template<typename Interface>
|
|
void addCleanup(Interface& iface, std::function<void()> cleanup)
|
|
{
|
|
addCleanup(typeid(Interface), &iface, std::move(cleanup));
|
|
}
|
|
|
|
//! IPC context struct accessor (see struct definition for more description).
|
|
virtual ipc::Context& context() = 0;
|
|
|
|
protected:
|
|
//! Internal implementation of public addCleanup method (above) as a
|
|
//! type-erased virtual function, since template functions can't be virtual.
|
|
virtual void addCleanup(std::type_index type, void* iface, std::function<void()> cleanup) = 0;
|
|
};
|
|
|
|
//! Return implementation of Ipc interface.
|
|
std::unique_ptr<Ipc> MakeIpc(const char* exe_name, const char* process_argv0, Init& init);
|
|
} // namespace interfaces
|
|
|
|
#endif // BITCOIN_INTERFACES_IPC_H
|