// Copyright (c) 2020-2024, The Monero Project
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#pragma once
#include <array>
#include <boost/thread/mutex.hpp>
#include <boost/utility/string_ref.hpp>
#include <cstdint>
#include <deque>
#include <memory>
#include <vector>
#include "cryptonote_basic/fwd.h"
#include "net/zmq.h"
#include "span.h"
#include "cryptonote_basic/difficulty.h"
namespace cryptonote { namespace listener
{
/*! \brief Sends ZMQ PUB messages on cryptonote events
Clients must ensure that all transaction(s) are notified before any blocks
they are contained in, and must ensure that each block is notified in chain
order. An external lock **must** be held by clients during the entire
txpool check and notification sequence and (a possibly second) lock is held
during the entire block check and notification sequence. Otherwise, events
could be sent in a different order than processed. */
class zmq_pub
{
/* Each socket has its own internal queue. So we can only use one socket, else
the messages being published are not guaranteed to be in the same order
pushed. */
net::zmq::socket relay_;
std::deque<std::vector<txpool_event>> txes_;
std::array<std::size_t, 2> chain_subs_;
std::array<std::size_t, 1> miner_subs_;
std::array<std::size_t, 2> txpool_subs_;
boost::mutex sync_; //!< Synchronizes counts in `*_subs_` arrays.
public:
//! \return Name of ZMQ_PAIR endpoint for pub notifications
static constexpr const char* relay_endpoint() noexcept { return "inproc://pub_relay"; }
explicit zmq_pub(void* context);
zmq_pub(const zmq_pub&) = delete;
zmq_pub(zmq_pub&&) = delete;
~zmq_pub();
zmq_pub& operator=(const zmq_pub&) = delete;
zmq_pub& operator=(zmq_pub&&) = delete;
//! Process a client subscription request (from XPUB sockets). Thread-safe.
bool sub_request(const boost::string_ref message);
/*! Forward ZMQ messages sent to `relay` via `send_chain_main` or
`send_txpool_add` to `pub`. Used by `ZmqServer`. */
bool relay_to_pub(void* relay, void* pub);
/*! Send a `ZMQ_PUB` notification for a change to the main chain.
Thread-safe.
\return Number of ZMQ messages sent to relay. */
std::size_t send_chain_main(std::uint64_t height, epee::span<const cryptonote::block> blocks);
/*! Send a `ZMQ_PUB` notification for a new miner data.
Thread-safe.
\return Number of ZMQ messages sent to relay. */
std::size_t send_miner_data(uint8_t major_version, uint64_t height, const crypto::hash& prev_id, const crypto::hash& seed_hash, difficulty_type diff, uint64_t median_weight, uint64_t already_generated_coins, const std::vector<tx_block_template_backlog_entry>& tx_backlog);
/*! Send a `ZMQ_PUB` notification for new tx(es) being added to the local
pool. Thread-safe.
\return Number of ZMQ messages sent to relay. */
std::size_t send_txpool_add(std::vector<cryptonote::txpool_event> txes);
//! Callable for `send_chain_main` with weak ownership to `zmq_pub` object.
struct chain_main
{
std::weak_ptr<zmq_pub> self_;
void operator()(std::uint64_t height, epee::span<const cryptonote::block> blocks) const;
};
//! Callable for `send_miner_data` with weak ownership to `zmq_pub` object.
struct miner_data
{
std::weak_ptr<zmq_pub> self_;
void operator()(uint8_t major_version, uint64_t height, const crypto::hash& prev_id, const crypto::hash& seed_hash, difficulty_type diff, uint64_t median_weight, uint64_t already_generated_coins, const std::vector<tx_block_template_backlog_entry>& tx_backlog) const;
};
//! Callable for `send_txpool_add` with weak ownership to `zmq_pub` object.
struct txpool_add
{
std::weak_ptr<zmq_pub> self_;
void operator()(std::vector<cryptonote::txpool_event> txes) const;
};
};
}}
