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Stable release v32.1bitcoin/bitcoin · f0de87f04062 ↗3,020 source files · 47.5 MB stored on the server340 file guides

Release published 2026-10-28 · Snapshot fetched 2026-11-01. Latest stable release at fetch time; development branches and Git history are excluded. Only the selected code window and visible folders load here.

12,666 bytes · SHA-256 a6e109f09060dfea… · View upstream ↗

1// Copyright (c) 2020-present 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#include <util/sock.h>
6
7#include <compat/compat.h>
8#include <span.h>
9#include <tinyformat.h>
10#include <util/check.h>
11#include <util/log.h>
12#include <util/syserror.h>
13#include <util/threadinterrupt.h>
14#include <util/time.h>
15
16#include <algorithm>
17#include <compare>
18#include <exception>
19#include <limits>
20#include <memory>
21#include <stdexcept>
22#include <string>
23#include <utility>
24#include <vector>
25
26#ifdef USE_POLL
27#include <poll.h>
28#endif
29
30Sock::Sock(SOCKET s) : m_socket(s) {}
31
32Sock::Sock(Sock&& other)
33{
34    m_socket = other.m_socket;
35    other.m_socket = INVALID_SOCKET;
36}
37
38Sock::~Sock() { Close(); }
39
40Sock& Sock::operator=(Sock&& other)
41{
42    Close();
43    m_socket = other.m_socket;
44    other.m_socket = INVALID_SOCKET;
45    return *this;
46}
47
48ssize_t Sock::Send(const void* data, size_t len, int flags) const
49{
50    return send(m_socket, static_cast<const char*>(data), len, flags);
51}
52
53ssize_t Sock::Recv(void* buf, size_t len, int flags) const
54{
55    return recv(m_socket, static_cast<char*>(buf), len, flags);
56}
57
58int Sock::Connect(const sockaddr* addr, socklen_t addr_len) const
59{
60    return connect(m_socket, addr, addr_len);
61}
62
63int Sock::Bind(const sockaddr* addr, socklen_t addr_len) const
64{
65    return bind(m_socket, addr, addr_len);
66}
67
68int Sock::Listen(int backlog) const
69{
70    return listen(m_socket, backlog);
71}
72
73std::unique_ptr<Sock> Sock::Accept(sockaddr* addr, socklen_t* addr_len) const
74{
75#ifdef WIN32
76    static constexpr auto accept_error = INVALID_SOCKET;
77#else
78    static constexpr auto accept_error = SOCKET_ERROR;
79#endif
80
81    std::unique_ptr<Sock> sock;
82
83    const auto socket = accept(m_socket, addr, addr_len);
84    if (socket != accept_error) {
85        try {
86            sock = std::make_unique<Sock>(socket);
87        } catch (const std::exception&) {
88#ifdef WIN32
89            closesocket(socket);
90#else
91            close(socket);
92#endif
93        }
94    }
95
96    return sock;
97}
98
99int Sock::GetSockOpt(int level, int opt_name, void* opt_val, socklen_t* opt_len) const
100{
101    return getsockopt(m_socket, level, opt_name, static_cast<char*>(opt_val), opt_len);
102}
103
104int Sock::SetSockOpt(int level, int opt_name, const void* opt_val, socklen_t opt_len) const
105{
106    return setsockopt(m_socket, level, opt_name, static_cast<const char*>(opt_val), opt_len);
107}
108
109int Sock::GetSockName(sockaddr* name, socklen_t* name_len) const
110{
111    return getsockname(m_socket, name, name_len);
112}
113
114bool Sock::SetNonBlocking() const
115{
116#ifdef WIN32
117    u_long on{1};
118    if (ioctlsocket(m_socket, FIONBIO, &on) == SOCKET_ERROR) {
119        return false;
120    }
121#else
122    const int flags{fcntl(m_socket, F_GETFL, 0)};
123    if (flags == SOCKET_ERROR) {
124        return false;
125    }
126    if (fcntl(m_socket, F_SETFL, flags | O_NONBLOCK) == SOCKET_ERROR) {
127        return false;
128    }
129#endif
130    return true;
131}
132
133bool Sock::IsSelectable() const
134{
135#if defined(USE_POLL) || defined(WIN32)
136    return true;
137#else
138    return m_socket < FD_SETSIZE;
139#endif
140}
141
142bool Sock::Wait(std::chrono::milliseconds timeout, Event requested, Event* occurred) const
143{
144    // We need a `shared_ptr` holding `this` for `WaitMany()`, but don't want
145    // `this` to be destroyed when the `shared_ptr` goes out of scope at the
146    // end of this function.
147    // Create it with an aliasing shared_ptr that points to `this` without
148    // owning it.
149    std::shared_ptr<const Sock> shared{std::shared_ptr<const Sock>{}, this};
150
151    EventsPerSock events_per_sock{std::make_pair(shared, Events{requested})};
152
153    if (!WaitMany(timeout, events_per_sock)) {
154        return false;
155    }
156
157    if (occurred != nullptr) {
158        *occurred = events_per_sock.begin()->second.occurred;
159    }
160
161    return true;
162}
163
164bool Sock::WaitMany(std::chrono::milliseconds timeout, EventsPerSock& events_per_sock) const
165{
166    // poll() takes the timeout as an int and select() rejects very large values on
167    // some systems (e.g. macOS), so cap it at INT_MAX milliseconds (~24.8 days).
168    timeout = std::min(timeout, std::chrono::milliseconds{std::numeric_limits<int>::max()});
169
170#ifdef USE_POLL
171    std::vector<pollfd> pfds;
172    for (const auto& [sock, events] : events_per_sock) {
173        pfds.emplace_back();
174        auto& pfd = pfds.back();
175        pfd.fd = sock->m_socket;
176        if (events.requested & RecvEvent) {
177            pfd.events |= POLLIN;
178        }
179        if (events.requested & SendEvent) {
180            pfd.events |= POLLOUT;
181        }
182    }
183
184    if (poll(pfds.data(), pfds.size(), count_milliseconds(timeout)) == SOCKET_ERROR) {
185        return false;
186    }
187
188    assert(pfds.size() == events_per_sock.size());
189    size_t i{0};
190    for (auto& [sock, events] : events_per_sock) {
191        assert(sock->m_socket == static_cast<SOCKET>(pfds[i].fd));
192        events.occurred = 0;
193        if (pfds[i].revents & POLLIN) {
194            events.occurred |= RecvEvent;
195        }
196        if (pfds[i].revents & POLLOUT) {
197            events.occurred |= SendEvent;
198        }
199        if (pfds[i].revents & (POLLERR | POLLHUP)) {
200            events.occurred |= ErrorEvent;
201        }
202        ++i;
203    }
204
205    return true;
206#else
207    fd_set recv;
208    fd_set send;
209    fd_set err;
210    FD_ZERO(&recv);
211    FD_ZERO(&send);
212    FD_ZERO(&err);
213    SOCKET socket_max{0};
214
215    for (const auto& [sock, events] : events_per_sock) {
216        if (!sock->IsSelectable()) {
217            return false;
218        }
219        const auto& s = sock->m_socket;
220        if (events.requested & RecvEvent) {
221            FD_SET(s, &recv);
222            FD_SET(s, &err);
223        }
224        if (events.requested & SendEvent) {
225            FD_SET(s, &send);
226        }
227        if (events.requested & (RecvEvent | SendEvent)) {
228            socket_max = std::max(socket_max, s);
229        }
230    }
231
232    timeval tv = MillisToTimeval(timeout);
233
234    if (select(socket_max + 1, &recv, &send, &err, &tv) == SOCKET_ERROR) {
235        return false;
236    }
237
238    for (auto& [sock, events] : events_per_sock) {
239        const auto& s = sock->m_socket;
240        events.occurred = 0;
241        if (FD_ISSET(s, &recv)) {
242            events.occurred |= RecvEvent;
243        }
244        if (FD_ISSET(s, &send)) {
245            events.occurred |= SendEvent;
246        }
247        if (FD_ISSET(s, &err)) {
248            events.occurred |= ErrorEvent;
249        }
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

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