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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.

9,872 bytes · SHA-256 70de6f21d04c0b1d… · View upstream ↗

1// Copyright (c) 2019-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#ifndef BITCOIN_UTIL_STRING_H
6#define BITCOIN_UTIL_STRING_H
7
8#include <algorithm>
9#include <array>
10#include <cstddef>
11#include <cstdint>
12#include <initializer_list>
13#include <locale>
14#include <optional>
15#include <span>
16#include <sstream>
17#include <string>
18#include <string_view>
19#include <vector>
20
21#include <attributes.h>
22
23namespace util {
24namespace detail {
25template <unsigned num_params>
26constexpr void CheckNumFormatSpecifiers(const char* str)
27{
28    unsigned count_normal{0}; // Number of "normal" specifiers, like %s
29    unsigned count_pos{0};    // Max number in positional specifier, like %8$s
30    for (auto it{str}; *it != '\0'; ++it) {
31        if (*it != '%' || *++it == '%') continue; // Skip escaped %%
32
33        auto add_arg = [&] {
34            unsigned maybe_num{0};
35            while ('0' <= *it && *it <= '9') {
36                maybe_num *= 10;
37                maybe_num += *it - '0';
38                ++it;
39            }
40
41            if (*it == '$') {
42                ++it;
43                // Positional specifier, like %8$s
44                if (maybe_num == 0) throw "Positional format specifier must have position of at least 1";
45                count_pos = std::max(count_pos, maybe_num);
46            } else {
47                // Non-positional specifier, like %s
48                ++count_normal;
49            }
50        };
51
52        // Increase argument count and consume positional specifier, if present.
53        add_arg();
54
55        // Consume flags.
56        while (*it == '#' || *it == '0' || *it == '-' || *it == ' ' || *it == '+') ++it;
57
58        auto parse_size = [&] {
59            if (*it == '*') {
60                ++it;
61                add_arg();
62            } else {
63                while ('0' <= *it && *it <= '9') ++it;
64            }
65        };
66
67        // Consume dynamic or static width value.
68        parse_size();
69
70        // Consume dynamic or static precision value.
71        if (*it == '.') {
72            ++it;
73            parse_size();
74        }
75
76        if (*it == '\0') throw "Format specifier incorrectly terminated by end of string";
77
78        // Length and type in "[flags][width][.precision][length]type"
79        // is not checked. Parsing continues with the next '%'.
80    }
81    if (count_normal && count_pos) throw "Format specifiers must be all positional or all non-positional!";
82    unsigned count{count_normal | count_pos};
83    if (num_params != count) throw "Format specifier count must match the argument count!";
84}
85} // namespace detail
86
87/**
88 * @brief A wrapper for a compile-time partially validated format string
89 *
90 * This struct can be used to enforce partial compile-time validation of format
91 * strings, to reduce the likelihood of tinyformat throwing exceptions at
92 * run-time. Validation is partial to try and prevent the most common errors
93 * while avoiding re-implementing the entire parsing logic.
94 */
95template <unsigned num_params>
96struct ConstevalFormatString {
97    const char* const fmt;
98    consteval ConstevalFormatString(const char* str) : fmt{str} { detail::CheckNumFormatSpecifiers<num_params>(fmt); }
99};
100
101/// Replace every non-overlapping occurrence of `search` with `substitute`, treating both literally; the replacement text is not searched again.
102void ReplaceAll(std::string& in_out, std::string_view search, std::string_view substitute);
103
104/** Split a string on any char found in separators, returning a vector.
105 *
106 * If sep does not occur in sp, a singleton with the entirety of sp is returned.
107 *
108 * @param[in] include_sep Whether to include the separator at the end of the left side of the splits.
109 *
110 * Note that this function does not care about braces, so splitting
111 * "foo(bar(1),2),3) on ',' will return {"foo(bar(1)", "2)", "3)"}.
112 *
113 * If include_sep == true, splitting "foo(bar(1),2),3) on ','
114 * will return:
115 *  - foo(bar(1),
116 *  - 2),
117 *  - 3)
118 */
119template <typename T = std::span<const char>>
120std::vector<T> Split(std::span<const char> sp LIFETIMEBOUND, std::string_view separators, bool include_sep = false)
121{
122    std::vector<T> ret;
123    auto it = sp.begin();
124    auto start = it;
125    while (it != sp.end()) {
126        if (separators.find(*it) != std::string::npos) {
127            if (include_sep) {
128                ret.emplace_back(start, it + 1);
129            } else {
130                ret.emplace_back(start, it);
131            }
132            start = it + 1;
133        }
134        ++it;
135    }
136    ret.emplace_back(start, it);
137    return ret;
138}
139
140/** Split a string on every instance of sep, returning a vector.
141 *
142 * If sep does not occur in sp, a singleton with the entirety of sp is returned.
143 *
144 * Note that this function does not care about braces, so splitting
145 * "foo(bar(1),2),3) on ',' will return {"foo(bar(1)", "2)", "3)"}.
146 */
147template <typename T = std::span<const char>>
148std::vector<T> Split(std::span<const char> sp LIFETIMEBOUND, char sep, bool include_sep = false)
149{
150    return Split<T>(sp, std::string_view{&sep, 1}, include_sep);
151}
152
153[[nodiscard]] inline std::vector<std::string> SplitString(std::string_view str, char sep)
154{
155    return Split<std::string>(str, sep);
156}
157
158[[nodiscard]] inline std::vector<std::string> SplitString(std::string_view str, std::string_view separators)
159{
160    return Split<std::string>(str, separators);
161}
162
163[[nodiscard]] inline std::string_view TrimStringView(std::string_view str LIFETIMEBOUND, std::string_view pattern = " \f\n\r\t\v")
164{
165    std::string::size_type front = str.find_first_not_of(pattern);
166    if (front == std::string::npos) {
167        return {};
168    }
169    std::string::size_type end = str.find_last_not_of(pattern);
170    return str.substr(front, end - front + 1);
171}
172
173[[nodiscard]] inline std::string TrimString(std::string_view str, std::string_view pattern = " \f\n\r\t\v")
174{
175    return std::string(TrimStringView(str, pattern));
176}
177
178[[nodiscard]] inline std::string_view RemoveSuffixView(std::string_view str LIFETIMEBOUND, std::string_view suffix)
179{
180    if (str.ends_with(suffix)) {
181        return str.substr(0, str.size() - suffix.size());
182    }
183    return str;
184}
185
186[[nodiscard]] inline std::string_view RemovePrefixView(std::string_view str LIFETIMEBOUND, std::string_view prefix)
187{
188    if (str.starts_with(prefix)) {
189        return str.substr(prefix.size());
190    }
191    return str;
192}
193
194[[nodiscard]] inline std::string RemovePrefix(std::string_view str, std::string_view prefix)
195{
196    return std::string(RemovePrefixView(str, prefix));
197}
198
199/**
200 * Join all container items. Typically used to concatenate strings but accepts
201 * containers with elements of any type.
202 *
203 * @param container The items to join
204 * @param separator The separator
205 * @param unary_op  Apply this operator to each item
206 */
207template <typename C, typename S, typename UnaryOp>
208// NOLINTNEXTLINE(misc-no-recursion)
209auto Join(const C& container, const S& separator, UnaryOp unary_op)
210{
211    decltype(unary_op(*container.begin())) ret;
212    bool first{true};
213    for (const auto& item : container) {
214        if (!first) ret += separator;
215        ret += unary_op(item);
216        first = false;
217    }
218    return ret;
219}
220
221template <typename C, typename S>
222auto Join(const C& container, const S& separator)
223{
224    return Join(container, separator, [](const auto& i) { return i; });
225}
226
227/**
228 * Create an unordered multi-line list of items.
229 */
230inline std::string MakeUnorderedList(const std::vector<std::string>& items)
231{
232    return Join(items, "\n", [](const std::string& item) { return "- " + item; });
233}
234
235/**
236 * Check if a string contains any embedded NUL (\0) characters
237 */
238[[nodiscard]] inline bool ContainsNUL(std::string_view str) noexcept
239{
240    for (auto c : str) {
241        if (c == 0) return true;
242    }
243    return false;
244}
245
246/**
247 * Locale-independent version of std::to_string
248 */
249template <typename T>
250std::string ToString(const T& t)

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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