Use byte_slice for sending zmq messages - removes data copy within zmq

This commit is contained in:
Lee Clagett 2019-11-17 06:06:10 +00:00
parent 378cdeaeae
commit da99157462
11 changed files with 138 additions and 27 deletions

View file

@ -42,7 +42,12 @@ namespace epee
struct release_byte_slice
{
void operator()(byte_slice_data*) const noexcept;
//! For use with `zmq_message_init_data`, use second arg for buffer pointer.
static void call(void*, void* ptr) noexcept;
void operator()(byte_slice_data* ptr) const noexcept
{
call(nullptr, ptr);
}
};
/*! Inspired by slices in golang. Storage is thread-safe reference counted,
@ -140,6 +145,9 @@ namespace epee
\throw std::out_of_range If `size() < end`.
\return Slice starting at `data() + begin` of size `end - begin`. */
byte_slice get_slice(std::size_t begin, std::size_t end) const;
//! \post `empty()` \return Ownership of ref-counted buffer.
std::unique_ptr<byte_slice_data, release_byte_slice> take_buffer() noexcept;
};
} // epee

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@ -49,12 +49,16 @@ namespace epee
std::atomic<std::size_t> ref_count;
};
void release_byte_slice::operator()(byte_slice_data* ptr) const noexcept
void release_byte_slice::call(void*, void* ptr) noexcept
{
if (ptr && --(ptr->ref_count) == 0)
if (ptr)
{
ptr->~byte_slice_data();
free(ptr);
byte_slice_data* self = static_cast<byte_slice_data*>(ptr);
if (--(self->ref_count) == 0)
{
self->~byte_slice_data();
free(self);
}
}
}
@ -206,4 +210,11 @@ namespace epee
return {};
return {storage_.get(), {portion_.begin() + begin, end - begin}};
}
std::unique_ptr<byte_slice_data, release_byte_slice> byte_slice::take_buffer() noexcept
{
std::unique_ptr<byte_slice_data, release_byte_slice> out{std::move(storage_)};
portion_ = nullptr;
return out;
}
} // epee

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@ -33,6 +33,8 @@
#include <limits>
#include <utility>
#include "byte_slice.h"
namespace net
{
namespace zmq
@ -183,6 +185,22 @@ namespace zmq
{
return retry_op(zmq_send, socket, payload.data(), payload.size(), flags);
}
expect<void> send(epee::byte_slice&& payload, void* socket, int flags) noexcept
{
void* const data = const_cast<std::uint8_t*>(payload.data());
const std::size_t size = payload.size();
auto buffer = payload.take_buffer(); // clears `payload` from callee
zmq_msg_t msg{};
MONERO_ZMQ_CHECK(zmq_msg_init_data(std::addressof(msg), data, size, epee::release_byte_slice::call, buffer.get()));
buffer.release(); // zmq will now decrement byte_slice ref-count
expect<void> sent = retry_op(zmq_msg_send, std::addressof(msg), socket, flags);
if (!sent) // beware if removing `noexcept` from this function - possible leak here
zmq_msg_close(std::addressof(msg));
return sent;
}
} // zmq
} // net

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@ -53,6 +53,11 @@
#define MONERO_ZMQ_THROW(msg) \
MONERO_THROW( ::net::zmq::get_error_code(), msg )
namespace epee
{
class byte_slice;
}
namespace net
{
namespace zmq
@ -132,5 +137,24 @@ namespace zmq
\param flags See `zmq_send` for possible flags.
\return `success()` if sent, otherwise ZMQ error. */
expect<void> send(epee::span<const std::uint8_t> payload, void* socket, int flags = 0) noexcept;
/*! Sends `payload` on `socket`. Blocks until the entire message is queued
for sending, or until `zmq_term` is called on the `zmq_context`
associated with `socket`. If the context is terminated,
`make_error_code(ETERM)` is returned.
\note This will automatically retry on `EINTR`, so exiting on
interrupts requires context termination.
\note If non-blocking behavior is requested on `socket` or by `flags`,
then `net::zmq::make_error_code(EAGAIN)` will be returned if this
would block.
\param payload sent as one message on `socket`.
\param socket Handle created with `zmq_socket`.
\param flags See `zmq_msg_send` for possible flags.
\post `payload.emtpy()` - ownership is transferred to zmq.
\return `success()` if sent, otherwise ZMQ error. */
expect<void> send(epee::byte_slice&& payload, void* socket, int flags = 0) noexcept;
} // zmq
} // net

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@ -33,6 +33,7 @@
#include <stdexcept>
#include <boost/uuid/nil_generator.hpp>
#include <boost/utility/string_ref.hpp>
// likely included by daemon_handler.h's includes,
// but including here for clarity
#include "cryptonote_core/cryptonote_core.h"
@ -48,7 +49,7 @@ namespace rpc
{
namespace
{
using handler_function = std::string(DaemonHandler& handler, const rapidjson::Value& id, const rapidjson::Value& msg);
using handler_function = epee::byte_slice(DaemonHandler& handler, const rapidjson::Value& id, const rapidjson::Value& msg);
struct handler_map
{
const char* method_name;
@ -66,7 +67,7 @@ namespace rpc
}
template<typename Message>
std::string handle_message(DaemonHandler& handler, const rapidjson::Value& id, const rapidjson::Value& parameters)
epee::byte_slice handle_message(DaemonHandler& handler, const rapidjson::Value& id, const rapidjson::Value& parameters)
{
typename Message::Request request{};
request.fromJson(parameters);
@ -903,7 +904,7 @@ namespace rpc
return true;
}
std::string DaemonHandler::handle(const std::string& request)
epee::byte_slice DaemonHandler::handle(const std::string& request)
{
MDEBUG("Handling RPC request: " << request);
@ -916,8 +917,11 @@ namespace rpc
if (matched_handler == std::end(handlers) || matched_handler->method_name != request_type)
return BAD_REQUEST(request_type, req_full.getID());
std::string response = matched_handler->call(*this, req_full.getID(), req_full.getMessage());
MDEBUG("Returning RPC response: " << response);
epee::byte_slice response = matched_handler->call(*this, req_full.getID(), req_full.getMessage());
const boost::string_ref response_view{reinterpret_cast<const char*>(response.data()), response.size()};
MDEBUG("Returning RPC response: " << response_view);
return response;
}
catch (const std::exception& e)

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@ -28,6 +28,7 @@
#pragma once
#include "byte_slice.h"
#include "daemon_messages.h"
#include "daemon_rpc_version.h"
#include "rpc_handler.h"
@ -132,7 +133,7 @@ class DaemonHandler : public RpcHandler
void handle(const GetOutputDistribution::Request& req, GetOutputDistribution::Response& res);
std::string handle(const std::string& request);
epee::byte_slice handle(const std::string& request) override final;
private:

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@ -149,7 +149,7 @@ cryptonote::rpc::error FullMessage::getError()
return err;
}
std::string FullMessage::getRequest(const std::string& request, const Message& message, const unsigned id)
epee::byte_slice FullMessage::getRequest(const std::string& request, const Message& message, const unsigned id)
{
rapidjson::StringBuffer buffer;
{
@ -172,11 +172,11 @@ std::string FullMessage::getRequest(const std::string& request, const Message& m
if (!dest.IsComplete())
throw std::logic_error{"Invalid JSON tree generated"};
}
return std::string{buffer.GetString(), buffer.GetSize()};
return epee::byte_slice{{buffer.GetString(), buffer.GetSize()}};
}
std::string FullMessage::getResponse(const Message& message, const rapidjson::Value& id)
epee::byte_slice FullMessage::getResponse(const Message& message, const rapidjson::Value& id)
{
rapidjson::StringBuffer buffer;
{
@ -207,17 +207,17 @@ std::string FullMessage::getResponse(const Message& message, const rapidjson::Va
if (!dest.IsComplete())
throw std::logic_error{"Invalid JSON tree generated"};
}
return std::string{buffer.GetString(), buffer.GetSize()};
return epee::byte_slice{{buffer.GetString(), buffer.GetSize()}};
}
// convenience functions for bad input
std::string BAD_REQUEST(const std::string& request)
epee::byte_slice BAD_REQUEST(const std::string& request)
{
rapidjson::Value invalid;
return BAD_REQUEST(request, invalid);
}
std::string BAD_REQUEST(const std::string& request, const rapidjson::Value& id)
epee::byte_slice BAD_REQUEST(const std::string& request, const rapidjson::Value& id)
{
Message fail;
fail.status = Message::STATUS_BAD_REQUEST;
@ -225,7 +225,7 @@ std::string BAD_REQUEST(const std::string& request, const rapidjson::Value& id)
return FullMessage::getResponse(fail, id);
}
std::string BAD_JSON(const std::string& error_details)
epee::byte_slice BAD_JSON(const std::string& error_details)
{
rapidjson::Value invalid;
Message fail;

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@ -33,6 +33,7 @@
#include <rapidjson/writer.h>
#include <string>
#include "byte_slice.h"
#include "rpc/message_data_structs.h"
namespace cryptonote
@ -85,8 +86,8 @@ namespace rpc
cryptonote::rpc::error getError();
static std::string getRequest(const std::string& request, const Message& message, unsigned id);
static std::string getResponse(const Message& message, const rapidjson::Value& id);
static epee::byte_slice getRequest(const std::string& request, const Message& message, unsigned id);
static epee::byte_slice getResponse(const Message& message, const rapidjson::Value& id);
private:
FullMessage() = default;
@ -99,10 +100,10 @@ namespace rpc
// convenience functions for bad input
std::string BAD_REQUEST(const std::string& request);
std::string BAD_REQUEST(const std::string& request, const rapidjson::Value& id);
epee::byte_slice BAD_REQUEST(const std::string& request);
epee::byte_slice BAD_REQUEST(const std::string& request, const rapidjson::Value& id);
std::string BAD_JSON(const std::string& error_details);
epee::byte_slice BAD_JSON(const std::string& error_details);
} // namespace rpc

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@ -32,6 +32,7 @@
#include <cstdint>
#include <string>
#include <vector>
#include "byte_slice.h"
#include "crypto/hash.h"
namespace cryptonote
@ -54,7 +55,7 @@ class RpcHandler
RpcHandler() { }
virtual ~RpcHandler() { }
virtual std::string handle(const std::string& request) = 0;
virtual epee::byte_slice handle(const std::string& request) = 0;
static boost::optional<output_distribution_data>
get_output_distribution(const std::function<bool(uint64_t, uint64_t, uint64_t, uint64_t&, std::vector<uint64_t>&, uint64_t&)> &f, uint64_t amount, uint64_t from_height, uint64_t to_height, const std::function<crypto::hash(uint64_t)> &get_hash, bool cumulative, uint64_t blockchain_height);

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@ -28,10 +28,13 @@
#include "zmq_server.h"
#include <boost/utility/string_ref.hpp>
#include <chrono>
#include <cstdint>
#include <system_error>
#include "byte_slice.h"
namespace cryptonote
{
@ -73,10 +76,11 @@ void ZmqServer::serve()
{
const std::string message = MONERO_UNWRAP(net::zmq::receive(socket.get()));
MDEBUG("Received RPC request: \"" << message << "\"");
const std::string& response = handler.handle(message);
epee::byte_slice response = handler.handle(message);
MONERO_UNWRAP(net::zmq::send(epee::strspan<std::uint8_t>(response), socket.get()));
MDEBUG("Sent RPC reply: \"" << response << "\"");
const boost::string_ref response_view{reinterpret_cast<const char*>(response.data()), response.size()};
MDEBUG("Sending RPC reply: \"" << response_view << "\"");
MONERO_UNWRAP(net::zmq::send(std::move(response), socket.get()));
}
}
catch (const std::system_error& e)

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@ -1702,6 +1702,45 @@ TEST(zmq, read_write)
EXPECT_EQ(message, *received);
}
TEST(zmq, read_write_slice)
{
net::zmq::context context{zmq_init(1)};
ASSERT_NE(nullptr, context);
net::zmq::socket send_socket{zmq_socket(context.get(), ZMQ_REQ)};
net::zmq::socket recv_socket{zmq_socket(context.get(), ZMQ_REP)};
ASSERT_NE(nullptr, send_socket);
ASSERT_NE(nullptr, recv_socket);
ASSERT_EQ(0u, zmq_bind(recv_socket.get(), "inproc://testing"));
ASSERT_EQ(0u, zmq_connect(send_socket.get(), "inproc://testing"));
std::string message;
message.resize(1024);
crypto::rand(message.size(), reinterpret_cast<std::uint8_t*>(std::addressof(message[0])));
{
epee::byte_slice slice_message{{epee::strspan<std::uint8_t>(message)}};
ASSERT_TRUE(bool(net::zmq::send(std::move(slice_message), send_socket.get())));
EXPECT_TRUE(slice_message.empty());
}
const expect<std::string> received = net::zmq::receive(recv_socket.get());
ASSERT_TRUE(bool(received));
EXPECT_EQ(message, *received);
}
TEST(zmq, write_slice_fail)
{
std::string message;
message.resize(1024);
crypto::rand(message.size(), reinterpret_cast<std::uint8_t*>(std::addressof(message[0])));
epee::byte_slice slice_message{std::move(message)};
EXPECT_FALSE(bool(net::zmq::send(std::move(slice_message), nullptr)));
EXPECT_TRUE(slice_message.empty());
}
TEST(zmq, read_write_multipart)
{
net::zmq::context context{zmq_init(1)};