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

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bitcoin / src / leveldb / util / crc32c.cc

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251}
252
253// Returns the smallest address >= the given address that is aligned to N bytes.
254//
255// N must be a power of two.
256template <int N>
257constexpr inline const uint8_t* RoundUp(const uint8_t* pointer) {
258  return reinterpret_cast<uint8_t*>(
259      (reinterpret_cast<uintptr_t>(pointer) + (N - 1)) &
260      ~static_cast<uintptr_t>(N - 1));
261}
262
263}  // namespace
264
265// Determine if the CPU running this program can accelerate the CRC32C
266// calculation.
267static bool CanAccelerateCRC32C() {
268  // port::AcceleretedCRC32C returns zero when unable to accelerate.
269  static const char kTestCRCBuffer[] = "TestCRCBuffer";
270  static const char kBufSize = sizeof(kTestCRCBuffer) - 1;
271  static const uint32_t kTestCRCValue = 0xdcbc59fa;
272
273  return port::AcceleratedCRC32C(0, kTestCRCBuffer, kBufSize) == kTestCRCValue;
274}
275
276uint32_t Extend(uint32_t crc, const char* data, size_t n) {
277  static bool accelerate = CanAccelerateCRC32C();
278  if (accelerate) {
279    return port::AcceleratedCRC32C(crc, data, n);
280  }
281
282  const uint8_t* p = reinterpret_cast<const uint8_t*>(data);
283  const uint8_t* e = p + n;
284  uint32_t l = crc ^ kCRC32Xor;
285
286// Process one byte at a time.
287#define STEP1                              \
288  do {                                     \
289    int c = (l & 0xff) ^ *p++;             \
290    l = kByteExtensionTable[c] ^ (l >> 8); \
291  } while (0)
292
293// Process one of the 4 strides of 4-byte data.
294#define STEP4(s)                                                               \
295  do {                                                                         \
296    crc##s = ReadUint32LE(p + s * 4) ^ kStrideExtensionTable3[crc##s & 0xff] ^ \
297             kStrideExtensionTable2[(crc##s >> 8) & 0xff] ^                    \
298             kStrideExtensionTable1[(crc##s >> 16) & 0xff] ^                   \
299             kStrideExtensionTable0[crc##s >> 24];                             \
300  } while (0)
301
302// Process a 16-byte swath of 4 strides, each of which has 4 bytes of data.
303#define STEP16 \
304  do {         \
305    STEP4(0);  \
306    STEP4(1);  \
307    STEP4(2);  \
308    STEP4(3);  \
309    p += 16;   \
310  } while (0)
311
312// Process 4 bytes that were already loaded into a word.
313#define STEP4W(w)                                   \
314  do {                                              \
315    w ^= l;                                         \
316    for (size_t i = 0; i < 4; ++i) {                \
317      w = (w >> 8) ^ kByteExtensionTable[w & 0xff]; \
318    }                                               \
319    l = w;                                          \
320  } while (0)
321
322  // Point x at first 4-byte aligned byte in the buffer. This might be past the
323  // end of the buffer.
324  const uint8_t* x = RoundUp<4>(p);
325  if (x <= e) {
326    // Process bytes p is 4-byte aligned.
327    while (p != x) {
328      STEP1;
329    }
330  }
331
332  if ((e - p) >= 16) {
333    // Load a 16-byte swath into the stride partial results.
334    uint32_t crc0 = ReadUint32LE(p + 0 * 4) ^ l;
335    uint32_t crc1 = ReadUint32LE(p + 1 * 4);
336    uint32_t crc2 = ReadUint32LE(p + 2 * 4);
337    uint32_t crc3 = ReadUint32LE(p + 3 * 4);
338    p += 16;
339
340    // It is possible to get better speeds (at least on x86) by interleaving
341    // prefetching 256 bytes ahead with processing 64 bytes at a time. See the
342    // portable implementation in https://github.com/google/crc32c/.
343
344    // Process one 16-byte swath at a time.
345    while ((e - p) >= 16) {
346      STEP16;
347    }
348
349    // Advance one word at a time as far as possible.
350    while ((e - p) >= 4) {
351      STEP4(0);
352      uint32_t tmp = crc0;
353      crc0 = crc1;
354      crc1 = crc2;
355      crc2 = crc3;
356      crc3 = tmp;
357      p += 4;
358    }
359
360    // Combine the 4 partial stride results.
361    l = 0;
362    STEP4W(crc0);
363    STEP4W(crc1);
364    STEP4W(crc2);
365    STEP4W(crc3);
366  }
367
368  // Process the last few bytes.
369  while (p != e) {
370    STEP1;
371  }
372#undef STEP4W
373#undef STEP16
374#undef STEP4
375#undef STEP1
376  return l ^ kCRC32Xor;
377}
378
379}  // namespace crc32c
380}  // namespace leveldb
381

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440 guided files · 2,580 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

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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