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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.

bitcoin / bitcoinstable

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▤ interfaces.cppGuide

▤ license_info.cppGuide

▤ license_info.hGuide

▤ run_command.cppGuide

▤ arith_uint256.hGuide

▤ bitcoin-chainstate.cpp

▤ bitcoin-cli-res.rc

▤ bitcoin-cli.cppGuide

▤ bitcoin-res.rc

▤ bitcoin-tx-res.rc

▤ bitcoin-tx.cpp

▤ bitcoin-util-res.rc

▤ bitcoin-util.cpp

▤ bitcoin-wallet-res.rc

▤ blockencodings.cppGuide

▤ blockencodings.hGuide

▤ blockfilter.cppGuide

▤ blockfilter.hGuide

▤ chain.cppGuide

▤ chain.h

▤ chainparams.cppGuide

▤ chainparams.h

▤ chainparamsbase.cppGuide

▤ chainparamsbase.hGuide

▤ chainparamsseeds.h

▤ checkqueue.hGuide

▤ clientversion.cpp

▤ clientversion.hGuide

▤ cluster_linearize.h

▤ CMakeLists.txt

▤ coins.cppGuide

▤ coins.hGuide

▤ compressor.cppGuide

▤ deploymentstatus.cpp

▤ deploymentstatus.h

▤ dummywallet.cpp

▤ external_signer.cpp

▤ merkleblock.cppGuide

▤ merkleblock.hGuide

▤ musig.cpp

▤ musig.h

▤ net_permissions.cppGuide

▤ net_permissions.h

▤ net_processing.cppGuide

▤ netaddress.cppGuide

▤ private_broadcast.cpp

▤ private_broadcast.h

▤ threadsafety.hGuide

▤ tinyformat.h

▤ torcontrol.cppGuide

▤ validation.cppGuide

▤ validation.h

▤ validationinterface.cpp

▤ validationinterface.h

▤ versionbits_impl.h

▤ versionbits.cpp

▤ versionbits.h

▤ walletinitinterface.h

▤ CMakeLists.txtGuide

▤ libbitcoinkernel.pc.in

bitcoin / src / common / netif.cpp

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15,294 bytes · SHA-256 22d9c9591d1d832e… · View upstream ↗

251        if ((msg_pos + sizeof(rt_msghdr)) > buf.size()) return std::nullopt;
252        const struct rt_msghdr* rt = (const struct rt_msghdr*)(buf.data() + msg_pos);
253        const size_t next_msg_pos = msg_pos + rt->rtm_msglen;
254        if (rt->rtm_msglen < sizeof(rt_msghdr) || next_msg_pos > buf.size()) return std::nullopt;
255        // Iterate over addresses within message, get destination and gateway (if present).
256        // Address data starts after header.
257        size_t sa_pos = msg_pos + sizeof(struct rt_msghdr);
258        std::optional<CNetAddr> dst, gateway;
259        for (int i = 0; i < RTAX_MAX; i++) {
260            if (rt->rtm_addrs & (1 << i)) {
261                // 2 is just sa_len + sa_family, the theoretical minimum size of a socket address.
262                if ((sa_pos + 2) > next_msg_pos) return std::nullopt;
263                const struct sockaddr* sa = (const struct sockaddr*)(buf.data() + sa_pos);
264                if ((sa_pos + sa->sa_len) > next_msg_pos) return std::nullopt;
265                if (i == RTAX_DST) {
266                    dst = FromSockAddr(sa, sa->sa_len);
267                } else if (i == RTAX_GATEWAY) {
268                    gateway = FromSockAddr(sa, sa->sa_len);
269                }
270                // Skip sockaddr entries for bit flags we're not interested in,
271                // move cursor.
272                sa_pos += ROUNDUP32(sa->sa_len);
273            }
274        }
275        // Found default gateway?
276        if (dst && gateway && dst->IsBindAny()) { // Route to 0.0.0.0 or :: ?
277            return *gateway;
278        }
279        // Skip to next message.
280        msg_pos = next_msg_pos;
281    }
282    return std::nullopt;
283}
284
285#else
286
287// Dummy implementation.
288std::optional<CNetAddr> QueryDefaultGatewayImpl(sa_family_t)
289{
290    return std::nullopt;
291}
292
293#endif
294
295}
296
297std::optional<CNetAddr> QueryDefaultGateway(Network network)
298{
299    Assume(network == NET_IPV4 || network == NET_IPV6);
300
301    sa_family_t family;
302    if (network == NET_IPV4) {
303        family = AF_INET;
304    } else if(network == NET_IPV6) {
305        family = AF_INET6;
306    } else {
307        return std::nullopt;
308    }
309
310    std::optional<CNetAddr> ret = QueryDefaultGatewayImpl(family);
311
312    // It's possible for the default gateway to be 0.0.0.0 or ::0 on at least Windows
313    // for some routing strategies. If so, return as if no default gateway was found.
314    if (ret && !ret->IsBindAny()) {
315        return ret;
316    } else {
317        return std::nullopt;
318    }
319}
320
321std::vector<CNetAddr> GetLocalAddresses()
322{
323    std::vector<CNetAddr> addresses;
324#ifdef WIN32
325    DWORD status = 0;
326    constexpr size_t MAX_ADAPTER_ADDR_SIZE = 4 * 1000 * 1000; // Absolute maximum size of adapter addresses structure we're willing to handle, as a precaution.
327    std::vector<std::byte> out_buf(15000, {}); // Start with 15KB allocation as recommended in GetAdaptersAddresses documentation.
328    while (true) {
329        ULONG out_buf_len = out_buf.size();
330        status = GetAdaptersAddresses(AF_UNSPEC, GAA_FLAG_SKIP_ANYCAST | GAA_FLAG_SKIP_MULTICAST | GAA_FLAG_SKIP_DNS_SERVER | GAA_FLAG_SKIP_FRIENDLY_NAME,
331                nullptr, reinterpret_cast<PIP_ADAPTER_ADDRESSES>(out_buf.data()), &out_buf_len);
332        if (status == ERROR_BUFFER_OVERFLOW && out_buf.size() < MAX_ADAPTER_ADDR_SIZE) {
333            // If status == ERROR_BUFFER_OVERFLOW, out_buf_len will contain the needed size.
334            // Unfortunately, this cannot be fully relied on, because another process may have added interfaces.
335            // So to avoid getting stuck due to a race condition, double the buffer size at least
336            // once before retrying (but only up to the maximum allowed size).
337            out_buf.resize(std::min(std::max<size_t>(out_buf_len, out_buf.size()) * 2, MAX_ADAPTER_ADDR_SIZE));
338        } else {
339            break;
340        }
341    }
342
343    if (status != NO_ERROR) {
344        // This includes ERROR_NO_DATA if there are no addresses and thus there's not even one PIP_ADAPTER_ADDRESSES
345        // record in the returned structure.
346        LogError("Could not get local adapter addresses: %s\n", NetworkErrorString(status));
347        return addresses;
348    }
349
350    // Iterate over network adapters.
351    for (PIP_ADAPTER_ADDRESSES cur_adapter = reinterpret_cast<PIP_ADAPTER_ADDRESSES>(out_buf.data());
352         cur_adapter != nullptr; cur_adapter = cur_adapter->Next) {
353        if (cur_adapter->OperStatus != IfOperStatusUp) continue;
354        if (cur_adapter->IfType == IF_TYPE_SOFTWARE_LOOPBACK) continue;
355
356        // Iterate over unicast addresses for adapter, the only address type we're interested in.
357        for (PIP_ADAPTER_UNICAST_ADDRESS cur_address = cur_adapter->FirstUnicastAddress;
358             cur_address != nullptr; cur_address = cur_address->Next) {
359            // "The IP address is a cluster address and should not be used by most applications."
360            if ((cur_address->Flags & IP_ADAPTER_ADDRESS_TRANSIENT) != 0) continue;
361
362            if (std::optional<CNetAddr> addr = FromSockAddr(cur_address->Address.lpSockaddr, static_cast<socklen_t>(cur_address->Address.iSockaddrLength))) {
363                addresses.push_back(*addr);
364            }
365        }
366    }
367#elif defined(HAVE_IFADDRS)
368    struct ifaddrs* myaddrs;
369    if (getifaddrs(&myaddrs) == 0) {
370        for (struct ifaddrs* ifa = myaddrs; ifa != nullptr; ifa = ifa->ifa_next)
371        {
372            if (ifa->ifa_addr == nullptr) continue;
373            if ((ifa->ifa_flags & IFF_UP) == 0) continue;
374            if ((ifa->ifa_flags & IFF_LOOPBACK) != 0) continue;
375
376            if (std::optional<CNetAddr> addr = FromSockAddr(ifa->ifa_addr, std::nullopt)) {
377                addresses.push_back(*addr);
378            }
379        }
380        freeifaddrs(myaddrs);
381    }
382#endif
383    return addresses;
384}
385

A READING COMPANION

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This file is included in the stable source snapshot. A file-specific guide has not been published yet.

340 guided files · 2,680 pending. Guides cover key sections, not every line.

cmake/bitcoin-build-config.h.in src/consensus/amount.h src/consensus/consensus.h src/primitives/block.h src/primitives/transaction.h src/crypto/sha256.h src/util/moneystr.h src/clientversion.h src/uint256.h src/script/script.h src/policy/policy.h CMakeLists.txt README.md COPYING src/consensus/tx_check.cpp src/consensus/tx_verify.cpp src/consensus/merkle.cpp src/pow.cpp src/validation.cpp src/script/interpreter.cpp src/script/solver.cpp src/script/sign.cpp src/key_io.cpp src/net.cpp src/net_processing.cpp src/netaddress.cpp src/protocol.h src/wallet/wallet.cpp src/wallet/spend.cpp

← Previous 250 linesCode page 2

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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