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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.

13,066 bytes · SHA-256 330ad83e5af22de3… · View upstream ↗

1// Copyright (c) 2016-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 <support/lockedpool.h>
6#include <support/cleanse.h>
7
8#ifdef WIN32
9#include <windows.h>
10#else
11#include <sys/mman.h>
12#include <sys/resource.h>
13#include <unistd.h>
14#endif
15
16#include <algorithm>
17#include <limits>
18#include <stdexcept>
19#include <utility>
20#ifdef ARENA_DEBUG
21#include <iomanip>
22#include <iostream>
23#endif
24
25LockedPoolManager* LockedPoolManager::_instance = nullptr;
26
27/*******************************************************************************/
28// Utilities
29//
30/** Align up to power of 2 */
31static inline size_t align_up(size_t x, size_t align)
32{
33    return (x + align - 1) & ~(align - 1);
34}
35
36/*******************************************************************************/
37// Implementation: Arena
38
39Arena::Arena(void *base_in, size_t size_in, size_t alignment_in):
40    base(base_in), end(static_cast<char*>(base_in) + size_in), alignment(alignment_in)
41{
42    // Start with one free chunk that covers the entire arena
43    auto it = size_to_free_chunk.emplace(size_in, base);
44    chunks_free.emplace(base, it);
45    chunks_free_end.emplace(static_cast<char*>(base) + size_in, it);
46}
47
48Arena::~Arena() = default;
49
50void* Arena::alloc(size_t size)
51{
52    // Round to next multiple of alignment
53    size = align_up(size, alignment);
54
55    // Don't handle zero-sized chunks
56    if (size == 0)
57        return nullptr;
58
59    // Pick a large enough free-chunk. Returns an iterator pointing to the first element that is not less than key.
60    // This allocation strategy is best-fit. According to "Dynamic Storage Allocation: A Survey and Critical Review",
61    // Wilson et. al. 1995, https://www.scs.stanford.edu/14wi-cs140/sched/readings/wilson.pdf, best-fit and first-fit
62    // policies seem to work well in practice.
63    auto size_ptr_it = size_to_free_chunk.lower_bound(size);
64    if (size_ptr_it == size_to_free_chunk.end())
65        return nullptr;
66
67    // Create the used-chunk, taking its space from the end of the free-chunk
68    const size_t size_remaining = size_ptr_it->first - size;
69    char* const free_chunk = static_cast<char*>(size_ptr_it->second);
70    auto allocated = chunks_used.emplace(free_chunk + size_remaining, size).first;
71    chunks_free_end.erase(free_chunk + size_ptr_it->first);
72    if (size_ptr_it->first == size) {
73        // whole chunk is used up
74        chunks_free.erase(size_ptr_it->second);
75    } else {
76        // still some memory left in the chunk
77        auto it_remaining = size_to_free_chunk.emplace(size_remaining, size_ptr_it->second);
78        chunks_free[size_ptr_it->second] = it_remaining;
79        chunks_free_end.emplace(free_chunk + size_remaining, it_remaining);
80    }
81    size_to_free_chunk.erase(size_ptr_it);
82
83    return allocated->first;
84}
85
86void Arena::free(void *ptr)
87{
88    // Freeing the nullptr pointer is OK.
89    if (ptr == nullptr) {
90        return;
91    }
92
93    // Remove chunk from used map
94    auto i = chunks_used.find(ptr);
95    if (i == chunks_used.end()) {
96        throw std::runtime_error("Arena: invalid or double free");
97    }
98    auto freed = std::make_pair(static_cast<char*>(i->first), i->second);
99    chunks_used.erase(i);
100
101    // coalesce freed with previous chunk
102    auto prev = chunks_free_end.find(freed.first);
103    if (prev != chunks_free_end.end()) {
104        freed.first -= prev->second->first;
105        freed.second += prev->second->first;
106        size_to_free_chunk.erase(prev->second);
107        chunks_free_end.erase(prev);
108    }
109
110    // coalesce freed with chunk after freed
111    auto next = chunks_free.find(freed.first + freed.second);
112    if (next != chunks_free.end()) {
113        freed.second += next->second->first;
114        size_to_free_chunk.erase(next->second);
115        chunks_free.erase(next);
116    }
117
118    // Add/set space with coalesced free chunk
119    auto it = size_to_free_chunk.emplace(freed.second, freed.first);
120    chunks_free[freed.first] = it;
121    chunks_free_end[freed.first + freed.second] = it;
122}
123
124Arena::Stats Arena::stats() const
125{
126    Arena::Stats r{ 0, 0, 0, chunks_used.size(), chunks_free.size() };
127    for (const auto& chunk: chunks_used)
128        r.used += chunk.second;
129    for (const auto& chunk: chunks_free)
130        r.free += chunk.second->first;
131    r.total = r.used + r.free;
132    return r;
133}
134
135#ifdef ARENA_DEBUG
136static void printchunk(void* base, size_t sz, bool used) {
137    std::cout <<
138        "0x" << std::hex << std::setw(16) << std::setfill('0') << base <<
139        " 0x" << std::hex << std::setw(16) << std::setfill('0') << sz <<
140        " 0x" << used << std::endl;
141}
142void Arena::walk() const
143{
144    for (const auto& chunk: chunks_used)
145        printchunk(chunk.first, chunk.second, true);
146    std::cout << std::endl;
147    for (const auto& chunk: chunks_free)
148        printchunk(chunk.first, chunk.second->first, false);
149    std::cout << std::endl;
150}
151#endif
152
153/*******************************************************************************/
154// Implementation: Win32LockedPageAllocator
155
156#ifdef WIN32
157/** LockedPageAllocator specialized for Windows.
158 */
159class Win32LockedPageAllocator: public LockedPageAllocator
160{
161public:
162    Win32LockedPageAllocator();
163    void* AllocateLocked(size_t len, bool *lockingSuccess) override;
164    void FreeLocked(void* addr, size_t len) override;
165    size_t GetLimit() override;
166private:
167    size_t page_size;
168};
169
170Win32LockedPageAllocator::Win32LockedPageAllocator()
171{
172    // Determine system page size in bytes
173    SYSTEM_INFO sSysInfo;
174    GetSystemInfo(&sSysInfo);
175    page_size = sSysInfo.dwPageSize;
176}
177void *Win32LockedPageAllocator::AllocateLocked(size_t len, bool *lockingSuccess)
178{
179    len = align_up(len, page_size);
180    void *addr = VirtualAlloc(nullptr, len, MEM_COMMIT | MEM_RESERVE, PAGE_READWRITE);
181    if (addr) {
182        // VirtualLock is used to attempt to keep keying material out of swap. Note
183        // that it does not provide this as a guarantee, but, in practice, memory
184        // that has been VirtualLock'd almost never gets written to the pagefile
185        // except in rare circumstances where memory is extremely low.
186        *lockingSuccess = VirtualLock(const_cast<void*>(addr), len) != 0;
187    }
188    return addr;
189}
190void Win32LockedPageAllocator::FreeLocked(void* addr, size_t len)
191{
192    len = align_up(len, page_size);
193    memory_cleanse(addr, len);
194    VirtualUnlock(const_cast<void*>(addr), len);
195}
196
197size_t Win32LockedPageAllocator::GetLimit()
198{
199    size_t min, max;
200    if(GetProcessWorkingSetSize(GetCurrentProcess(), &min, &max) != 0) {
201        return min;
202    }
203    return std::numeric_limits<size_t>::max();
204}
205#endif
206
207/*******************************************************************************/
208// Implementation: PosixLockedPageAllocator
209
210#ifndef WIN32
211/** LockedPageAllocator specialized for OSes that don't try to be
212 * special snowflakes.
213 */
214class PosixLockedPageAllocator: public LockedPageAllocator
215{
216public:
217    PosixLockedPageAllocator();
218    void* AllocateLocked(size_t len, bool *lockingSuccess) override;
219    void FreeLocked(void* addr, size_t len) override;
220    size_t GetLimit() override;
221private:
222    size_t page_size;
223};
224
225PosixLockedPageAllocator::PosixLockedPageAllocator()
226{
227    // Determine system page size in bytes
228#if defined(PAGESIZE) // defined in limits.h
229    page_size = PAGESIZE;
230#else                   // assume some POSIX OS
231    page_size = sysconf(_SC_PAGESIZE);
232#endif
233}
234
235void *PosixLockedPageAllocator::AllocateLocked(size_t len, bool *lockingSuccess)
236{
237    void *addr;
238    len = align_up(len, page_size);
239    addr = mmap(nullptr, len, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
240    if (addr == MAP_FAILED) {
241        return nullptr;
242    }
243    if (addr) {
244        *lockingSuccess = mlock(addr, len) == 0;
245#if defined(MADV_DONTDUMP) // Linux
246        madvise(addr, len, MADV_DONTDUMP);
247#elif defined(MADV_NOCORE) // FreeBSD
248        madvise(addr, len, MADV_NOCORE);
249#endif
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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