tdesktop/Telegram/SourceFiles/mtproto/sender.h

384 lines
11 KiB
C++

/*
This file is part of Telegram Desktop,
the official desktop version of Telegram messaging app, see https://telegram.org
Telegram Desktop is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
It is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
In addition, as a special exception, the copyright holders give permission
to link the code of portions of this program with the OpenSSL library.
Full license: https://github.com/telegramdesktop/tdesktop/blob/master/LICENSE
Copyright (c) 2014-2017 John Preston, https://desktop.telegram.org
*/
#pragma once
#include "base/variant.h"
namespace MTP {
class Instance;
Instance *MainInstance();
class Sender {
class RequestBuilder {
public:
RequestBuilder(const RequestBuilder &other) = delete;
RequestBuilder &operator=(const RequestBuilder &other) = delete;
RequestBuilder &operator=(RequestBuilder &&other) = delete;
protected:
using FailPlainHandler = base::lambda_once<void(const RPCError &error)>;
using FailRequestIdHandler = base::lambda_once<void(const RPCError &error, mtpRequestId requestId)>;
enum class FailSkipPolicy {
Simple,
HandleFlood,
HandleAll,
};
template <typename Response>
struct DonePlainPolicy {
using Callback = base::lambda_once<void(const Response &result)>;
static void handle(Callback &&handler, mtpRequestId requestId, Response &&result) {
handler(result);
}
};
template <typename Response>
struct DoneRequestIdPolicy {
using Callback = base::lambda_once<void(const Response &result, mtpRequestId requestId)>;
static void handle(Callback &&handler, mtpRequestId requestId, Response &&result) {
handler(result, requestId);
}
};
template <typename Response, template <typename> typename PolicyTemplate>
class DoneHandler : public RPCAbstractDoneHandler {
using Policy = PolicyTemplate<Response>;
using Callback = typename Policy::Callback;
public:
DoneHandler(gsl::not_null<Sender*> sender, Callback handler) : _sender(sender), _handler(std::move(handler)) {
}
void operator()(mtpRequestId requestId, const mtpPrime *from, const mtpPrime *end) override {
auto handler = std::move(_handler);
_sender->requestHandled(requestId);
if (handler) {
auto result = Response();
result.read(from, end);
Policy::handle(std::move(handler), requestId, std::move(result));
}
}
private:
gsl::not_null<Sender*> _sender;
Callback _handler;
};
struct FailPlainPolicy {
using Callback = base::lambda_once<void(const RPCError &error)>;
static void handle(Callback &&handler, mtpRequestId requestId, const RPCError &error) {
handler(error);
}
};
struct FailRequestIdPolicy {
using Callback = base::lambda_once<void(const RPCError &error, mtpRequestId requestId)>;
static void handle(Callback &&handler, mtpRequestId requestId, const RPCError &error) {
handler(error, requestId);
}
};
template <typename Policy>
class FailHandler : public RPCAbstractFailHandler {
using Callback = typename Policy::Callback;
public:
FailHandler(gsl::not_null<Sender*> sender, Callback handler, FailSkipPolicy skipPolicy)
: _sender(sender)
, _handler(std::move(handler))
, _skipPolicy(skipPolicy) {
}
bool operator()(mtpRequestId requestId, const RPCError &error) override {
if (_skipPolicy == FailSkipPolicy::Simple) {
if (MTP::isDefaultHandledError(error)) {
return false;
}
} else if (_skipPolicy == FailSkipPolicy::HandleFlood) {
if (MTP::isDefaultHandledError(error) && !MTP::isFloodError(error)) {
return false;
}
}
auto handler = std::move(_handler);
_sender->requestHandled(requestId);
if (handler) {
Policy::handle(std::move(handler), requestId, error);
}
return true;
}
private:
gsl::not_null<Sender*> _sender;
Callback _handler;
FailSkipPolicy _skipPolicy = FailSkipPolicy::Simple;
};
explicit RequestBuilder(gsl::not_null<Sender*> sender) noexcept : _sender(sender) {
}
RequestBuilder(RequestBuilder &&other) = default;
void setToDC(ShiftedDcId dcId) noexcept {
_dcId = dcId;
}
void setCanWait(TimeMs ms) noexcept {
_canWait = ms;
}
void setDoneHandler(RPCDoneHandlerPtr &&handler) noexcept {
_done = std::move(handler);
}
void setFailHandler(FailPlainHandler &&handler) noexcept {
_fail = std::move(handler);
}
void setFailHandler(FailRequestIdHandler &&handler) noexcept {
_fail = std::move(handler);
}
void setFailSkipPolicy(FailSkipPolicy policy) noexcept {
_failSkipPolicy = policy;
}
void setAfter(mtpRequestId requestId) noexcept {
_afterRequestId = requestId;
}
ShiftedDcId takeDcId() const noexcept {
return _dcId;
}
TimeMs takeCanWait() const noexcept {
return _canWait;
}
RPCDoneHandlerPtr takeOnDone() noexcept {
return std::move(_done);
}
RPCFailHandlerPtr takeOnFail() {
if (auto handler = base::get_if<FailPlainHandler>(&_fail)) {
return MakeShared<FailHandler<FailPlainPolicy>>(_sender, std::move(*handler), _failSkipPolicy);
} else if (auto handler = base::get_if<FailRequestIdHandler>(&_fail)) {
return MakeShared<FailHandler<FailRequestIdPolicy>>(_sender, std::move(*handler), _failSkipPolicy);
}
return RPCFailHandlerPtr();
}
mtpRequestId takeAfter() const noexcept {
return _afterRequestId;
}
gsl::not_null<Sender*> sender() const noexcept {
return _sender;
}
gsl::not_null<Instance*> instance() const noexcept {
return _sender->_instance;
}
void registerRequest(mtpRequestId requestId) {
_sender->requestRegister(requestId);
}
private:
gsl::not_null<Sender*> _sender;
ShiftedDcId _dcId = 0;
TimeMs _canWait = 0;
RPCDoneHandlerPtr _done;
base::variant<FailPlainHandler, FailRequestIdHandler> _fail;
FailSkipPolicy _failSkipPolicy = FailSkipPolicy::Simple;
mtpRequestId _afterRequestId = 0;
};
public:
Sender(gsl::not_null<Instance*> instance = MainInstance()) noexcept : _instance(instance) {
}
template <typename Request>
class SpecificRequestBuilder : public RequestBuilder {
private:
friend class Sender;
SpecificRequestBuilder(gsl::not_null<Sender*> sender, Request &&request) noexcept : RequestBuilder(sender), _request(std::move(request)) {
}
SpecificRequestBuilder(SpecificRequestBuilder &&other) = default;
public:
SpecificRequestBuilder &toDC(ShiftedDcId dcId) noexcept WARN_UNUSED_RESULT {
setToDC(dcId);
return *this;
}
SpecificRequestBuilder &canWait(TimeMs ms) noexcept WARN_UNUSED_RESULT {
setCanWait(ms);
return *this;
}
SpecificRequestBuilder &done(base::lambda_once<void(const typename Request::ResponseType &result)> callback) WARN_UNUSED_RESULT {
setDoneHandler(MakeShared<DoneHandler<typename Request::ResponseType, DonePlainPolicy>>(sender(), std::move(callback)));
return *this;
}
SpecificRequestBuilder &done(base::lambda_once<void(const typename Request::ResponseType &result, mtpRequestId requestId)> callback) WARN_UNUSED_RESULT {
setDoneHandler(MakeShared<DoneHandler<typename Request::ResponseType, DoneRequestIdPolicy>>(sender(), std::move(callback)));
return *this;
}
SpecificRequestBuilder &fail(base::lambda_once<void(const RPCError &error)> callback) noexcept WARN_UNUSED_RESULT {
setFailHandler(std::move(callback));
return *this;
}
SpecificRequestBuilder &fail(base::lambda_once<void(const RPCError &error, mtpRequestId requestId)> callback) noexcept WARN_UNUSED_RESULT {
setFailHandler(std::move(callback));
return *this;
}
SpecificRequestBuilder &handleFloodErrors() noexcept WARN_UNUSED_RESULT {
setFailSkipPolicy(FailSkipPolicy::HandleFlood);
return *this;
}
SpecificRequestBuilder &handleAllErrors() noexcept WARN_UNUSED_RESULT {
setFailSkipPolicy(FailSkipPolicy::HandleAll);
return *this;
}
SpecificRequestBuilder &after(mtpRequestId requestId) noexcept WARN_UNUSED_RESULT {
setAfter(requestId);
return *this;
}
mtpRequestId send() {
auto id = instance()->send(_request, takeOnDone(), takeOnFail(), takeDcId(), takeCanWait(), takeAfter());
registerRequest(id);
return id;
}
private:
Request _request;
};
class SentRequestWrap {
private:
friend class Sender;
SentRequestWrap(gsl::not_null<Sender*> sender, mtpRequestId requestId) : _sender(sender), _requestId(requestId) {
}
public:
void cancel() {
_sender->requestCancel(_requestId);
}
private:
gsl::not_null<Sender*> _sender;
mtpRequestId _requestId = 0;
};
template <typename Request, typename = std::enable_if_t<std::is_rvalue_reference<Request&&>::value>, typename = typename Request::Unboxed>
SpecificRequestBuilder<Request> request(Request &&request) noexcept WARN_UNUSED_RESULT;
SentRequestWrap request(mtpRequestId requestId) noexcept WARN_UNUSED_RESULT;
void requestSendDelayed() {
MTP::sendAnything();
}
void requestCancellingDiscard() {
for (auto &request : _requests) {
request.handled();
}
}
private:
class RequestWrap {
public:
RequestWrap(Instance *instance, mtpRequestId requestId) noexcept : _instance(instance), _id(requestId) {
}
mtpRequestId id() const noexcept {
return _id;
}
void handled() const noexcept {
_instance = nullptr;
}
~RequestWrap() {
if (_instance) {
_instance->cancel(_id);
}
}
private:
mutable Instance *_instance = nullptr;
mtpRequestId _id = 0;
};
struct RequestWrapComparator {
using is_transparent = std::true_type;
struct helper {
mtpRequestId requestId = 0;
helper() = default;
helper(const helper &other) = default;
helper(mtpRequestId requestId) noexcept : requestId(requestId) {
}
helper(const RequestWrap &request) noexcept : requestId(request.id()) {
}
bool operator<(helper other) const {
return requestId < other.requestId;
}
};
bool operator()(const helper &&lhs, const helper &&rhs) const {
return lhs < rhs;
}
};
template <typename Request>
friend class SpecialRequestBuilder;
friend class RequestBuilder;
friend class RequestWrap;
friend class SentRequestWrap;
void requestRegister(mtpRequestId requestId) {
_requests.emplace(_instance, requestId);
}
void requestHandled(mtpRequestId requestId) {
auto it = _requests.find(requestId);
if (it != _requests.cend()) {
it->handled();
_requests.erase(it);
}
}
void requestCancel(mtpRequestId requestId) {
auto it = _requests.find(requestId);
if (it != _requests.cend()) {
_requests.erase(it);
}
}
gsl::not_null<Instance*> _instance;
std::set<RequestWrap, RequestWrapComparator> _requests; // Better to use flatmap.
};
template <typename Request, typename, typename>
Sender::SpecificRequestBuilder<Request> Sender::request(Request &&request) noexcept {
return SpecificRequestBuilder<Request>(this, std::move(request));
}
inline Sender::SentRequestWrap Sender::request(mtpRequestId requestId) noexcept {
return SentRequestWrap(this, requestId);
}
} // namespace MTP