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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.

6,506 bytes · SHA-256 0bf5e52d78e6454c… · View upstream ↗

1// Copyright (c) 2009-2010 Satoshi Nakamoto
2// Copyright (c) 2009-present The Bitcoin Core developers
3// Distributed under the MIT software license, see the accompanying
4// file COPYING or http://www.opensource.org/licenses/mit-license.php.
5
6#include <arith_uint256.h>
7
8#include <crypto/common.h>
9#include <uint256.h>
10#include <util/overflow.h>
11
12#include <cassert>
13
14template <unsigned int BITS>
15base_uint<BITS>& base_uint<BITS>::operator<<=(unsigned int shift)
16{
17    base_uint<BITS> a(*this);
18    for (int i = 0; i < WIDTH; i++)
19        pn[i] = 0;
20    int k = shift / 32;
21    shift = shift % 32;
22    for (int i = 0; i < WIDTH; i++) {
23        if (i + k + 1 < WIDTH && shift != 0)
24            pn[i + k + 1] |= (a.pn[i] >> (32 - shift));
25        if (i + k < WIDTH)
26            pn[i + k] |= (a.pn[i] << shift);
27    }
28    return *this;
29}
30
31template <unsigned int BITS>
32base_uint<BITS>& base_uint<BITS>::operator>>=(unsigned int shift)
33{
34    base_uint<BITS> a(*this);
35    for (int i = 0; i < WIDTH; i++)
36        pn[i] = 0;
37    int k = shift / 32;
38    shift = shift % 32;
39    for (int i = 0; i < WIDTH; i++) {
40        if (i - k - 1 >= 0 && shift != 0)
41            pn[i - k - 1] |= (a.pn[i] << (32 - shift));
42        if (i - k >= 0)
43            pn[i - k] |= (a.pn[i] >> shift);
44    }
45    return *this;
46}
47
48template <unsigned int BITS>
49base_uint<BITS>& base_uint<BITS>::operator*=(uint32_t b32)
50{
51    uint64_t carry = 0;
52    for (int i = 0; i < WIDTH; i++) {
53        uint64_t n = carry + (uint64_t)b32 * pn[i];
54        pn[i] = n & 0xffffffff;
55        carry = n >> 32;
56    }
57    return *this;
58}
59
60template <unsigned int BITS>
61base_uint<BITS>& base_uint<BITS>::operator*=(const base_uint& b)
62{
63    base_uint<BITS> a;
64    for (int j = 0; j < WIDTH; j++) {
65        uint64_t carry = 0;
66        for (int i = 0; i + j < WIDTH; i++) {
67            uint64_t n = carry + a.pn[i + j] + (uint64_t)pn[j] * b.pn[i];
68            a.pn[i + j] = n & 0xffffffff;
69            carry = n >> 32;
70        }
71    }
72    *this = a;
73    return *this;
74}
75
76template <unsigned int BITS>
77base_uint<BITS>& base_uint<BITS>::operator/=(const base_uint& b)
78{
79    base_uint<BITS> div = b;     // make a copy, so we can shift.
80    base_uint<BITS> num = *this; // make a copy, so we can subtract.
81    *this = 0;                   // the quotient.
82    int num_bits = num.bits();
83    int div_bits = div.bits();
84    if (div_bits == 0)
85        throw uint_error("Division by zero");
86    if (div_bits > num_bits) // the result is certainly 0.
87        return *this;
88    int shift = num_bits - div_bits;
89    div <<= shift; // shift so that div and num align.
90    while (shift >= 0) {
91        if (num >= div) {
92            num -= div;
93            pn[shift / 32] |= (1U << (shift & 31)); // set a bit of the result.
94        }
95        div >>= 1; // shift back.
96        shift--;
97    }
98    // num now contains the remainder of the division.
99    return *this;
100}
101
102template <unsigned int BITS>
103int base_uint<BITS>::CompareTo(const base_uint<BITS>& b) const
104{
105    for (int i = WIDTH - 1; i >= 0; i--) {
106        if (pn[i] < b.pn[i])
107            return -1;
108        if (pn[i] > b.pn[i])
109            return 1;
110    }
111    return 0;
112}
113
114template <unsigned int BITS>
115bool base_uint<BITS>::EqualTo(uint64_t b) const
116{
117    for (int i = WIDTH - 1; i >= 2; i--) {
118        if (pn[i])
119            return false;
120    }
121    if (pn[1] != (b >> 32))
122        return false;
123    if (pn[0] != (b & 0xfffffffful))
124        return false;
125    return true;
126}
127
128template <unsigned int BITS>
129double base_uint<BITS>::getdouble() const
130{
131    double ret = 0.0;
132    double fact = 1.0;
133    for (int i = 0; i < WIDTH; i++) {
134        ret += fact * pn[i];
135        fact *= 4294967296.0;
136    }
137    return ret;
138}
139
140template <unsigned int BITS>
141std::string base_uint<BITS>::GetHex() const
142{
143    base_blob<BITS> b;
144    for (int x = 0; x < this->WIDTH; ++x) {
145        WriteLE32(b.begin() + x*4, this->pn[x]);
146    }
147    return b.GetHex();
148}
149
150template <unsigned int BITS>
151std::string base_uint<BITS>::ToString() const
152{
153    return GetHex();
154}
155
156template <unsigned int BITS>
157unsigned int base_uint<BITS>::bits() const
158{
159    for (int pos = WIDTH - 1; pos >= 0; pos--) {
160        if (pn[pos]) {
161            for (int nbits = 31; nbits > 0; nbits--) {
162                if (pn[pos] & 1U << nbits)
163                    return 32 * pos + nbits + 1;
164            }
165            return 32 * pos + 1;
166        }
167    }
168    return 0;
169}
170
171// Explicit instantiations for base_uint<256>
172template class base_uint<256>;
173
174// This implementation directly uses shifts instead of going
175// through an intermediate MPI representation.
176arith_uint256& arith_uint256::SetCompact(uint32_t nCompact, bool* pfNegative, bool* pfOverflow)
177{
178    int nSize = nCompact >> 24;
179    uint32_t nWord = nCompact & 0x007fffff;
180    if (nSize <= 3) {
181        nWord >>= 8 * (3 - nSize);
182        *this = nWord;
183    } else {
184        *this = nWord;
185        *this <<= 8 * (nSize - 3);
186    }
187    if (pfNegative)
188        *pfNegative = nWord != 0 && (nCompact & 0x00800000) != 0;
189    if (pfOverflow)
190        *pfOverflow = nWord != 0 && ((nSize > 34) ||
191                                     (nWord > 0xff && nSize > 33) ||
192                                     (nWord > 0xffff && nSize > 32));
193    return *this;
194}
195
196uint32_t arith_uint256::GetCompact(bool fNegative) const
197{
198    int nSize = CeilDiv(bits(), 8u);
199    uint32_t nCompact = 0;
200    if (nSize <= 3) {
201        nCompact = GetLow64() << 8 * (3 - nSize);
202    } else {
203        arith_uint256 bn = *this >> 8 * (nSize - 3);
204        nCompact = bn.GetLow64();
205    }
206    // The 0x00800000 bit denotes the sign.
207    // Thus, if it is already set, divide the mantissa by 256 and increase the exponent.
208    if (nCompact & 0x00800000) {
209        nCompact >>= 8;
210        nSize++;
211    }
212    assert((nCompact & ~0x007fffffU) == 0);
213    assert(nSize < 256);
214    nCompact |= nSize << 24;
215    nCompact |= (fNegative && (nCompact & 0x007fffff) ? 0x00800000 : 0);
216    return nCompact;
217}
218
219uint256 ArithToUint256(const arith_uint256 &a)
220{
221    uint256 b;
222    for(int x=0; x<a.WIDTH; ++x)
223        WriteLE32(b.begin() + x*4, a.pn[x]);
224    return b;
225}
226arith_uint256 UintToArith256(const uint256 &a)
227{
228    arith_uint256 b;
229    for(int x=0; x<b.WIDTH; ++x)
230        b.pn[x] = ReadLE32(a.begin() + x*4);
231    return b;
232}
233
234// Explicit instantiations for base_uint<6144> (used in test/fuzz/muhash.cpp).
235template base_uint<6144>& base_uint<6144>::operator*=(const base_uint<6144>& b);
236template base_uint<6144>& base_uint<6144>::operator/=(const base_uint<6144>& b);
237

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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