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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.

11,579 bytes · SHA-256 420eddbfb0ac6ac6… · 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#include <bitcoin-build-config.h> // IWYU pragma: keep
6
7#include <common/settings.h>
8
9#include <tinyformat.h>
10#include <univalue.h>
11#include <util/fs.h>
12
13#include <fstream>
14#include <iterator>
15#include <map>
16#include <string>
17#include <utility>
18#include <vector>
19
20namespace common {
21namespace {
22
23enum class Source {
24   FORCED,
25   COMMAND_LINE,
26   RW_SETTINGS,
27   CONFIG_FILE_NETWORK_SECTION,
28   CONFIG_FILE_DEFAULT_SECTION
29};
30
31// Json object key for the auto-generated warning comment
32const std::string SETTINGS_WARN_MSG_KEY{"_warning_"};
33
34//! Merge settings from multiple sources in precedence order:
35//! Forced config > command line > read-write settings file > config file network-specific section > config file default section
36//!
37//! This function is provided with a callback function fn that contains
38//! specific logic for how to merge the sources.
39template <typename Fn>
40static void MergeSettings(const Settings& settings, const std::string& section, const std::string& name, Fn&& fn)
41{
42    // Merge in the forced settings
43    if (auto* value = FindKey(settings.forced_settings, name)) {
44        fn(SettingsSpan(*value), Source::FORCED);
45    }
46    // Merge in the command-line options
47    if (auto* values = FindKey(settings.command_line_options, name)) {
48        fn(SettingsSpan(*values), Source::COMMAND_LINE);
49    }
50    // Merge in the read-write settings
51    if (const SettingsValue* value = FindKey(settings.rw_settings, name)) {
52        fn(SettingsSpan(*value), Source::RW_SETTINGS);
53    }
54    // Merge in the network-specific section of the config file
55    if (!section.empty()) {
56        if (auto* map = FindKey(settings.ro_config, section)) {
57            if (auto* values = FindKey(*map, name)) {
58                fn(SettingsSpan(*values), Source::CONFIG_FILE_NETWORK_SECTION);
59            }
60        }
61    }
62    // Merge in the default section of the config file
63    if (auto* map = FindKey(settings.ro_config, "")) {
64        if (auto* values = FindKey(*map, name)) {
65            fn(SettingsSpan(*values), Source::CONFIG_FILE_DEFAULT_SECTION);
66        }
67    }
68}
69} // namespace
70
71bool ReadSettings(const fs::path& path, std::map<std::string, SettingsValue>& values, std::vector<std::string>& errors)
72{
73    values.clear();
74    errors.clear();
75
76    // Ok for file to not exist
77    if (!fs::exists(path)) return true;
78
79    std::ifstream file;
80    file.open(path.std_path());
81    if (!file.is_open()) {
82      errors.emplace_back(strprintf("%s. Please check permissions.", fs::PathToString(path)));
83      return false;
84    }
85
86    SettingsValue in;
87    if (!in.read(std::string{std::istreambuf_iterator<char>(file), std::istreambuf_iterator<char>()})) {
88        errors.emplace_back(strprintf("Settings file %s does not contain valid JSON. This may be caused by a crash, power loss, full disk, or storage error, "
89                                      "and can be fixed by removing the file, which will reset settings to default values.",
90                                      fs::PathToString(path)));
91        return false;
92    }
93
94    if (file.fail()) {
95        errors.emplace_back(strprintf("Failed reading settings file %s", fs::PathToString(path)));
96        return false;
97    }
98    file.close(); // Done with file descriptor. Release while copying data.
99
100    if (!in.isObject()) {
101        errors.emplace_back(strprintf("Found non-object value %s in settings file %s", in.write(), fs::PathToString(path)));
102        return false;
103    }
104
105    const std::vector<std::string>& in_keys = in.getKeys();
106    const std::vector<SettingsValue>& in_values = in.getValues();
107    for (size_t i = 0; i < in_keys.size(); ++i) {
108        auto inserted = values.emplace(in_keys[i], in_values[i]);
109        if (!inserted.second) {
110            errors.emplace_back(strprintf("Found duplicate key %s in settings file %s", in_keys[i], fs::PathToString(path)));
111            values.clear();
112            break;
113        }
114    }
115
116    // Remove auto-generated warning comment from the accessible settings.
117    values.erase(SETTINGS_WARN_MSG_KEY);
118
119    return errors.empty();
120}
121
122bool WriteSettings(const fs::path& path,
123    const std::map<std::string, SettingsValue>& values,
124    std::vector<std::string>& errors)
125{
126    SettingsValue out(SettingsValue::VOBJ);
127    // Add auto-generated warning comment
128    out.pushKV(SETTINGS_WARN_MSG_KEY, strprintf("This file is automatically generated and updated by %s. Please do not edit this file while the node "
129                                                "is running, as any changes might be ignored or overwritten.", CLIENT_NAME));
130    // Push settings values
131    for (const auto& value : values) {
132        out.pushKVEnd(value.first, value.second);
133    }
134    std::ofstream file;
135    file.open(path.std_path());
136    if (file.fail()) {
137        errors.emplace_back(strprintf("Error: Unable to open settings file %s for writing", fs::PathToString(path)));
138        return false;
139    }
140    file << out.write(/* prettyIndent= */ 4, /* indentLevel= */ 1) << std::endl;
141    if (file.fail()) {
142        errors.emplace_back(strprintf("Error: Unable to write settings file %s", fs::PathToString(path)));
143        return false;
144    }
145    file.close();
146    if (file.fail()) {
147        errors.emplace_back(strprintf("Error: Unable to close settings file %s", fs::PathToString(path)));
148        return false;
149    }
150    return true;
151}
152
153SettingsValue GetSetting(const Settings& settings,
154    const std::string& section,
155    const std::string& name,
156    bool ignore_default_section_config,
157    bool ignore_nonpersistent,
158    bool get_chain_type)
159{
160    SettingsValue result;
161    bool done = false; // Done merging any more settings sources.
162    MergeSettings(settings, section, name, [&](SettingsSpan span, Source source) {
163        // Weird behavior preserved for backwards compatibility: Apply negated
164        // setting even if non-negated setting would be ignored. A negated
165        // value in the default section is applied to network specific options,
166        // even though normal non-negated values there would be ignored.
167        const bool never_ignore_negated_setting = span.last_negated();
168
169        // Weird behavior preserved for backwards compatibility: Take first
170        // assigned value instead of last. In general, later settings take
171        // precedence over early settings, but for backwards compatibility in
172        // the config file the precedence is reversed for all settings except
173        // chain type settings.
174        const bool reverse_precedence =
175            (source == Source::CONFIG_FILE_NETWORK_SECTION || source == Source::CONFIG_FILE_DEFAULT_SECTION) &&
176            !get_chain_type;
177
178        // Weird behavior preserved for backwards compatibility: Negated
179        // -regtest and -testnet arguments which you would expect to override
180        // values set in the configuration file are currently accepted but
181        // silently ignored. It would be better to apply these just like other
182        // negated values, or at least warn they are ignored.
183        const bool skip_negated_command_line = get_chain_type;
184
185        if (done) return;
186
187        // Ignore settings in default config section if requested.
188        if (ignore_default_section_config && source == Source::CONFIG_FILE_DEFAULT_SECTION &&
189            !never_ignore_negated_setting) {
190            return;
191        }
192
193        // Ignore nonpersistent settings if requested.
194        if (ignore_nonpersistent && (source == Source::COMMAND_LINE || source == Source::FORCED)) return;
195
196        // Skip negated command line settings.
197        if (skip_negated_command_line && span.last_negated()) return;
198
199        if (!span.empty()) {
200            result = reverse_precedence ? span.begin()[0] : span.end()[-1];
201            done = true;
202        } else if (span.last_negated()) {
203            result = false;
204            done = true;
205        }
206    });
207    return result;
208}
209
210std::vector<SettingsValue> GetSettingsList(const Settings& settings,
211    const std::string& section,
212    const std::string& name,
213    bool ignore_default_section_config)
214{
215    std::vector<SettingsValue> result;
216    bool done = false; // Done merging any more settings sources.
217    bool prev_negated_empty = false;
218    MergeSettings(settings, section, name, [&](SettingsSpan span, Source source) {
219        // Weird behavior preserved for backwards compatibility: Apply config
220        // file settings even if negated on command line. Negating a setting on
221        // command line will ignore earlier settings on the command line and
222        // ignore settings in the config file, unless the negated command line
223        // value is followed by non-negated value, in which case config file
224        // settings will be brought back from the dead (but earlier command
225        // line settings will still be ignored).
226        const bool add_zombie_config_values =
227            (source == Source::CONFIG_FILE_NETWORK_SECTION || source == Source::CONFIG_FILE_DEFAULT_SECTION) &&
228            !prev_negated_empty;
229
230        // Ignore settings in default config section if requested.
231        if (ignore_default_section_config && source == Source::CONFIG_FILE_DEFAULT_SECTION) return;
232
233        // Add new settings to the result if isn't already complete, or if the
234        // values are zombies.
235        if (!done || add_zombie_config_values) {
236            for (const auto& value : span) {
237                if (value.isArray()) {
238                    result.insert(result.end(), value.getValues().begin(), value.getValues().end());
239                } else {
240                    result.push_back(value);
241                }
242            }
243        }
244
245        // If a setting was negated, or if a setting was forced, set
246        // done to true to ignore any later lower priority settings.
247        done |= span.negated() > 0 || source == Source::FORCED;
248
249        // Update the negated and empty state used for the zombie values check.
250        prev_negated_empty |= span.last_negated() && result.empty();

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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