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Stable release v32.1bitcoin/bitcoin · f0de87f04062 ↗3,020 source files · 47.5 MB stored on the server440 file guides

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1// Copyright (c) The Bitcoin Core developers
2// Distributed under the MIT software license, see the accompanying
3// file COPYING or http://www.opensource.org/licenses/mit-license.php.
4
5#ifndef MP_PROXY_H
6#define MP_PROXY_H
7
8#include <mp/util.h>
9
10#include <cassert>
11#include <functional>
12#include <list>
13#include <memory>
14#include <stddef.h>
15#include <tuple>
16#include <type_traits>
17#include <utility>
18#include <variant> // IWYU pragma: keep
19
20namespace mp {
21class Connection;
22class EventLoop;
23//! Mapping from capnp interface type to proxy client implementation (specializations are generated by
24//! proxy-codegen.cpp).
25template <typename Interface> struct ProxyClient; // IWYU pragma: export
26//! Mapping from capnp interface type to proxy server implementation (specializations are generated by
27//! proxy-codegen.cpp).
28template <typename Interface> struct ProxyServer; // IWYU pragma: export
29//! Mapping from capnp method params type to method traits (specializations are generated by proxy-codegen.cpp).
30template <typename Params> struct ProxyMethod; // IWYU pragma: export
31//! Mapping from capnp struct type to struct traits (specializations are generated by proxy-codegen.cpp).
32template <typename Struct> struct ProxyStruct; // IWYU pragma: export
33//! Mapping from local c++ type to capnp type and traits (specializations are generated by proxy-codegen.cpp).
34template <typename Type> struct ProxyType; // IWYU pragma: export
35
36using CleanupList = std::list<std::function<void()>>;
37using CleanupIt = typename CleanupList::iterator;
38
39inline void CleanupRun(CleanupList& fns) {
40    while (!fns.empty()) {
41        auto fn = std::move(fns.front());
42        fns.pop_front();
43        fn();
44    }
45}
46
47//! Event loop smart pointer automatically managing m_num_refs.
48//! If a lock pointer argument is passed, the specified lock will be used,
49//! otherwise EventLoop::m_mutex will be locked when needed.
50class EventLoopRef
51{
52public:
53    explicit EventLoopRef(EventLoop& loop, Lock* lock = nullptr);
54    EventLoopRef(EventLoopRef&& other) noexcept : m_loop(other.m_loop) { other.m_loop = nullptr; }
55    EventLoopRef(const EventLoopRef&) = delete;
56    EventLoopRef& operator=(const EventLoopRef&) = delete;
57    EventLoopRef& operator=(EventLoopRef&&) = delete;
58    ~EventLoopRef() { reset(); }
59    EventLoop& operator*() const { assert(m_loop); return *m_loop; }
60    EventLoop* operator->() const { assert(m_loop); return m_loop; }
61    void reset(bool relock=false);
62
63    EventLoop* m_loop{nullptr};
64    Lock* m_lock{nullptr};
65};
66
67//! Context data associated with proxy client and server classes.
68struct ProxyContext
69{
70    Connection* connection;
71    EventLoopRef loop;
72    CleanupList cleanup_fns;
73
74    ProxyContext(Connection* connection);
75};
76
77//! Base class for generated ProxyClient classes that implement a C++ interface
78//! and forward calls to a capnp interface.
79template <typename Interface_, typename Impl_>
80class ProxyClientBase : public Impl_
81{
82public:
83    using Interface = Interface_;
84    using Impl = Impl_;
85    using Sub = ProxyClient<Interface>;
86    using Super = ProxyClientBase<Interface, Impl>;
87
88    //! Construct libmultiprocess client object wrapping Cap'n Proto client
89    //! object with a reference to the associated mp::Connection object.
90    //!
91    //! The destroy_connection option determines whether destroying this client
92    //! object closes the connection. It is set to true for the
93    //! ProxyClient<InitInterface> object returned by ConnectStream, to let IPC
94    //! clients close the connection by freeing the object. It is false for
95    //! other client objects so they can be destroyed without affecting the
96    //! connection.
97    ProxyClientBase(typename Interface::Client client, Connection* connection, bool destroy_connection);
98    ~ProxyClientBase() noexcept;
99
100    // construct/destroy methods called during client construction/destruction
101    // that can optionally be defined in capnp interfaces to invoke code on the
102    // server when proxy client objects are created and destroyed.
103    //
104    // The construct() method is not generally very useful, but can be used to
105    // run custom code on the server automatically when a ProxyClient client is
106    // constructed. The only current use is adding a construct method to Init
107    // interfaces that is called automatically on construction, so client and
108    // server exchange ThreadMap references and set Connection::m_thread_map
109    // values as soon as the Init client is created.
110    //
111    //     construct @0 (threadMap: Proxy.ThreadMap) -> (threadMap: Proxy.ThreadMap);
112    //
113    // But construct() is not necessary for this, thread maps could be passed
114    // through a normal method that is just called explicitly rather than
115    // implicitly.
116    //
117    // The destroy() method is more generally useful than construct(), because
118    // it ensures that the server object will be destroyed synchronously before
119    // the client destructor returns, instead of asynchronously at some
120    // unpredictable time after the client object is already destroyed and
121    // client code has moved on. If the destroy method accepts a Context
122    // parameter like:
123    //
124    //     destroy @0 (context: Proxy.Context) -> ();
125    //
126    // then it will also ensure that the destructor runs on the same thread the
127    // client used to make other RPC calls, instead of running on the server
128    // EventLoop thread and possibly blocking it.
129    static void construct(Super&) {}
130    static void destroy(Super&) {}
131
132    typename Interface::Client m_client;
133    ProxyContext m_context;
134};
135
136//! Customizable (through template specialization) base class used in generated ProxyClient implementations from
137//! proxy-codegen.cpp.
138template <typename Interface, typename Impl>
139class ProxyClientCustom : public ProxyClientBase<Interface, Impl>
140{
141    using ProxyClientBase<Interface, Impl>::ProxyClientBase;
142};
143
144//! Base class for generated ProxyServer classes that implement capnp server
145//! methods and forward calls to a wrapped c++ implementation class.
146template <typename Interface_, typename Impl_>
147struct ProxyServerBase : public virtual Interface_::Server
148{
149public:
150    using Interface = Interface_;
151    using Impl = Impl_;
152
153    ProxyServerBase(std::shared_ptr<Impl> impl, Connection& connection);
154    virtual ~ProxyServerBase();
155    void invokeDestroy();
156    using Interface_::Server::thisCap;
157
158    /**
159     * Implementation pointer that may or may not be owned and deleted when this
160     * capnp server goes out of scope. It is owned for servers created to wrap
161     * unique_ptr<Impl> method arguments, but unowned for servers created to
162     * wrap Impl& method arguments.
163     *
164     * In the case of Impl& arguments, custom code is required on other side of
165     * the connection to delete the capnp client & server objects since native
166     * code on that side of the connection will just be taking a plain reference
167     * rather than a pointer, so won't be able to do its own cleanup. Right now
168     * this is implemented with addCloseHook callbacks to delete clients at
169     * appropriate times depending on semantics of the particular method being
170     * wrapped. */
171    std::shared_ptr<Impl> m_impl;
172    ProxyContext m_context;
173};
174
175//! Customizable (through template specialization) base class which ProxyServer
176//! classes produced by generated code will inherit from. The default
177//! specialization of this class just inherits from ProxyServerBase, but custom
178//! specializations can be defined to control ProxyServer behavior.
179//!
180//! Specifically, it can be useful to specialize this class to add additional
181//! state to ProxyServer classes, for example to cache state between IPC calls.
182//! If this is done, however, care should be taken to ensure that the extra
183//! state can be destroyed without blocking, because ProxyServer destructors are
184//! called from the EventLoop thread, and if they block, it could deadlock the
185//! program. One way to do avoid blocking is to clean up the state by pushing
186//! cleanup callbacks to the m_context.cleanup_fns list, which run after the server
187//! m_impl object is destroyed on the same thread destroying it (which will
188//! either be an IPC worker thread if the ProxyServer is being explicitly
189//! destroyed by a client calling a destroy() method with a Context argument and
190//! Context.thread value set, or the temporary EventLoop::m_async_thread used to
191//! run destructors without blocking the event loop when no-longer used server
192//! objects are garbage collected by Cap'n Proto.) Alternately, if cleanup needs
193//! to run before m_impl is destroyed, the specialization can override
194//! invokeDestroy and destructor methods to do that.
195template <typename Interface, typename Impl>
196struct ProxyServerCustom : public ProxyServerBase<Interface, Impl>
197{
198    using ProxyServerBase<Interface, Impl>::ProxyServerBase;
199};
200
201//! Function traits class used to get method parameter and result types, used in
202//! generated ProxyClient and ProxyServer classes produced by gen.cpp to get C++
203//! method type information. The generated code accesses these traits via
204//! intermediate ProxyClientMethodTraits and ProxyServerMethodTraits classes,
205//! which it is possible to specialize to change the way method arguments and
206//! return values are handled.
207//!
208//! Fields of the trait class are:
209//!
210//! Params   - TypeList of C++ ClassName::methodName parameter types
211//! Result   - Return type of ClassName::method
212//! Param<N> - helper to access individual parameter types by index number.
213//! Fwd<N>   - helper to forward arguments by index number.
214//! Fields   - helper alias that appends Result type to the Params typelist if
215//!            it not void.
216template <class Fn>
217struct FunctionTraits;
218
219//! Specialization of above extracting result and params types assuming the
220//! template argument is a pointer-to-method type,
221//! decltype(&ClassName::methodName)
222template <class _Class, class _Result, class... _Params>
223struct FunctionTraits<_Result (_Class::*const)(_Params...)>
224{
225    using Params = TypeList<_Params...>;
226    using Result = _Result;
227    template <size_t N>
228    using Param = typename std::tuple_element<N, std::tuple<_Params...>>::type;
229    using Fields =
230        std::conditional_t<std::is_same_v<void, Result>, Params, TypeList<_Params..., _Result>>;
231
232    //! Enable perfect forwarding for clientInvoke calls. If parameter is a
233    //! value type or rvalue reference type, pass it as an rvalue-reference to
234    //! MakeClientParam and BuildField calls so it can be moved from, and if it
235    //! is an lvalue reference, pass it an lvalue reference so it won't be moved
236    //! from. This method does the same thing as std::forward except it takes a
237    //! parameter number instead of a type as a template argument, so generated
238    //! code calling this can be less repetitive and verbose.
239    template <size_t N>
240    static decltype(auto) Fwd(Param<N>& arg) { return static_cast<Param<N>&&>(arg); }
241};
242
243//! Traits class for a proxy method, providing the same
244//! Params/Result/Param/Fields described in the FunctionTraits class above, plus
245//! an additional invoke() method that calls the C++ method which is being
246//! proxied, forwarding any arguments.
247//!
248//! The template argument should be the InterfaceName::MethodNameParams class
249//! (generated by Cap'n Proto) associated with the method.
250//!

src/wallet/receive.cpp

src/wallet/coinselection.cpp

src/consensus/validation.h

src/primitives/transaction.cpp

src/script/descriptor.cpp

src/bitcoin-cli.cpp

src/rpc/blockchain.cpp

src/rpc/rawtransaction.cpp

src/init.cpp

src/crypto/sha256.cpp

src/consensus/merkle.h

src/consensus/tx_check.h

src/consensus/tx_verify.h

src/policy/feerate.h

src/policy/feerate.cpp

src/primitives/transaction_identifier.h

src/chainparamsbase.h

src/chainparamsbase.cpp

src/util/moneystr.cpp

src/crypto/ripemd160.h

src/crypto/sha1.h

src/crypto/sha512.h

src/crypto/hmac_sha256.h

src/crypto/hmac_sha512.h

src/crypto/hmac_sha256.cpp

src/crypto/hmac_sha512.cpp

src/crypto/hkdf_sha256_32.h

src/crypto/hkdf_sha256_32.cpp

src/support/cleanse.h

src/support/cleanse.cpp

src/crypto/siphash.cpp

src/crypto/muhash.h

src/crypto/chacha20.h

src/crypto/poly1305.h

src/crypto/chacha20poly1305.h

src/crypto/chacha20poly1305.cpp

src/util/chaintype.cpp

src/util/obfuscation.h

src/util/byte_units.h

src/util/overflow.h

src/blockencodings.cpp

src/net_permissions.cpp

src/policy/packages.cpp

src/policy/rbf.cpp

src/policy/truc_policy.cpp

src/policy/ephemeral_policy.cpp

src/policy/settings.cpp

src/policy/policy.cpp

src/node/transaction.cpp

src/node/coin.cpp

src/rpc/client.cpp

src/rpc/external_signer.cpp

src/rpc/request.cpp

src/rpc/server_util.cpp

src/rpc/fees.cpp

src/rpc/output_script.cpp

src/rpc/rawtransaction_util.cpp

src/rpc/rawtransaction_util.h

src/rpc/register.h

src/rpc/request.h

src/rpc/server_util.h

src/rpc/protocol.h

src/rpc/server.h

src/rpc/signmessage.cpp

src/rpc/txoutproof.cpp

src/rpc/util.cpp

src/rpc/util.h

src/wallet/rpc/addresses.cpp

src/wallet/rpc/backup.cpp

src/wallet/rpc/coins.cpp

src/wallet/rpc/encrypt.cpp

src/wallet/rpc/signmessage.cpp

src/wallet/rpc/util.cpp

src/wallet/rpc/util.h

src/wallet/coincontrol.cpp

src/wallet/coincontrol.h

src/wallet/context.cpp

src/wallet/context.h

src/wallet/crypter.cpp

src/wallet/crypter.h

src/wallet/db.cpp

src/wallet/export.cpp

src/wallet/external_signer_scriptpubkeyman.cpp

src/wallet/rpc/spend.cpp

src/wallet/rpc/transactions.cpp

src/wallet/rpc/wallet.cpp

src/wallet/feebumper.cpp

src/wallet/feebumper.h

src/index/base.h

src/index/base.cpp

src/index/txindex.h

src/index/txindex.cpp

src/index/txindex_key.h

src/index/txospenderindex.h

src/index/txospenderindex.cpp

src/index/blockfilterindex.h

src/index/blockfilterindex.cpp

src/index/coinstatsindex.h

src/index/coinstatsindex.cpp

src/index/db_key.h

src/index/disktxpos.h

src/kernel/chain.cpp

src/kernel/chain.h

src/kernel/checks.cpp

src/kernel/checks.h

src/kernel/context.cpp

src/kernel/context.h

src/kernel/cs_main.cpp

src/kernel/cs_main.h

src/kernel/disconnected_transactions.cpp

src/kernel/disconnected_transactions.h

src/kernel/mempool_removal_reason.cpp

src/kernel/mempool_removal_reason.h

src/kernel/coinstats.cpp

src/kernel/coinstats.h

src/kernel/chainparams.cpp

src/kernel/chainparams.h

src/wallet/sqlite.cpp

src/wallet/sqlite.h

src/wallet/transaction.cpp

src/wallet/transaction.h

src/wallet/dump.cpp

src/wallet/dump.h

src/wallet/init.cpp

src/wallet/walletutil.cpp

src/wallet/walletutil.h

src/wallet/wallettool.cpp

src/wallet/wallettool.h

src/wallet/export.h

src/wallet/migrate.cpp

src/wallet/migrate.h

src/wallet/db.h

src/wallet/walletdb.cpp

src/wallet/interfaces.cpp

src/wallet/scriptpubkeyman.cpp

src/wallet/scriptpubkeyman.h

src/kernel/bitcoinkernel.cpp

src/kernel/bitcoinkernel.h

src/kernel/bitcoinkernel_wrapper.h

src/node/chainstate.cpp

src/node/chainstate.h

src/node/blockstorage.cpp

src/node/blockstorage.h

src/node/mempool_persist.cpp

src/node/mempool_persist.h

src/node/utxo_snapshot.cpp

src/node/utxo_snapshot.h

src/node/kernel_notifications.cpp

src/node/kernel_notifications.h

src/node/blockmanager_args.cpp

src/kernel/blockmanager_opts.h

src/util/expected.cpp

src/policy/settings.h

src/util/types.h

src/kernel/messagestartchars.h

src/kernel/warning.h

src/util/exception.h

src/common/license_info.h

src/node/coins_view_args.h

src/node/database_args.h

src/util/batchpriority.h

src/util/ui_change_type.h

src/node/coins_view_args.cpp

src/node/peerman_args.h

src/util/serfloat.h

src/node/blockmanager_args.h

src/node/database_args.cpp

src/util/overloaded.h

src/interfaces/types.h

src/node/chainstatemanager_args.h

src/node/minisketchwrapper.h

src/util/macros.h

src/util/syserror.h

src/common/run_command.h

src/util/bytevectorhash.cpp

src/node/mempool_persist_args.cpp

src/util/exec.h

src/util/rbf.h

src/crypto/hex_base.h

src/node/mempool_persist_args.h

src/interfaces/echo.h

src/util/any.h

src/util/batchpriority.cpp

src/util/threadnames.h

src/node/coin.h

src/node/mempool_args.h

src/util/asmap.h

src/util/bytevectorhash.h

src/node/context.cpp

src/util/insert.h

src/util/readwritefile.h

src/node/peerman_args.cpp

src/node/interface_ui.cpp

src/interfaces/handler.h

src/node/mining_args.h

src/util/hasher.cpp

src/common/init.h

src/kernel/mempool_limits.h

src/common/system.h

src/crypto/sha3.h

src/util/threadinterrupt.cpp

src/node/protocol_version.h

src/util/exception.cpp

src/common/messages.h

src/node/connection_types.cpp

src/util/bip32.h

src/common/license_info.cpp

src/util/stdmutex.h

src/common/run_command.cpp

src/util/check.cpp

src/util/golombrice.h

src/node/types.h

src/node/timeoffsets.h

src/util/readwritefile.cpp

src/util/fastrange.h

src/util/signalinterrupt.h

src/util/task_runner.h

src/util/syserror.cpp

src/common/interfaces.cpp

src/common/types.h

src/util/threadinterrupt.h

src/kernel/chainstatemanager_opts.h

src/node/psbt.h

src/policy/ephemeral_policy.h

src/util/trace.h

src/common/url.cpp

src/kernel/mempool_options.h

src/util/serfloat.cpp

src/kernel/notifications_interface.h

src/node/timeoffsets.cpp

src/node/warnings.cpp

src/util/hash_type.h

src/crypto/hex_base.cpp

src/node/eviction.h

src/util/tokenbucket.h

src/crypto/aes.h

src/common/pcp.h

src/util/feefrac.cpp

src/node/transaction.h

src/util/threadnames.cpp

src/common/signmessage.h

src/util/exec.cpp

src/util/signalinterrupt.cpp

src/clientversion.cpp

src/common/signmessage.cpp

src/compat/assumptions.h

src/compat/byteswap.h

src/deploymentinfo.cpp

src/deploymentinfo.h

src/deploymentstatus.cpp

src/deploymentstatus.h

src/dummywallet.cpp

src/external_signer.h

src/init/bitcoin-gui.cpp

src/init/bitcoin-node.cpp

src/init/bitcoin-qt.cpp

src/init/bitcoin-wallet.cpp

src/init/bitcoind.cpp

src/init/common.h

src/interfaces/init.h

src/interfaces/ipc.h

src/key_io.h

src/logging/categories.h

src/logging/timer.h

src/mapport.h

src/musig.h

src/net_permissions.h

src/netgroup.h

src/netmessagemaker.h

src/node/chainstatemanager_args.cpp

src/node/connection_types.h

src/node/context.h

src/node/interface_ui.h

src/node/mempool_args.cpp

src/node/mining_args.cpp

src/node/minisketchwrapper.cpp

src/node/txreconciliation.h

src/policy/fees/estimator_args.cpp

src/policy/fees/estimator_args.h

src/policy/fees/estimator_man.cpp

src/policy/fees/estimator_man.h

src/policy/packages.h

src/policy/rbf.h

src/policy/truc_policy.h

src/pow.h

src/primitives/block.cpp

src/randomenv.h

src/rest.h

src/script/keyorigin.h

src/script/parsing.cpp

src/script/parsing.h

src/script/script_error.h

src/script/sigcache.cpp

src/script/sigcache.h

src/script/solver.h

src/script/verify_flags.h

src/semaphore_grant.h

src/signet.h

src/span.h

src/support/allocators/secure.h

src/support/allocators/zeroafterfree.h

src/util/tokenpipe.cpp

src/util/translation.h

src/util/vector.h

src/versionbits.h

src/versionbits_impl.h

src/wallet/external_signer_scriptpubkeyman.h

src/wallet/fees.h

src/wallet/load.h

src/wallet/receive.h

src/wallet/rpc/wallet.h

src/wallet/types.h

src/walletinitinterface.h

src/zmq/zmqabstractnotifier.cpp

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