git / moonbite-core / src/util/settings.cpp · raw

// Copyright (c) 2019 The Bitcoin Core developers// Distributed under the MIT software license, see the accompanying// file COPYING or http://www.opensource.org/licenses/mit-license.php.#include <util/settings.h>#include <tinyformat.h>#include <univalue.h>namespace util {namespace {enum class Source {   FORCED,   COMMAND_LINE,   RW_SETTINGS,   CONFIG_FILE_NETWORK_SECTION,   CONFIG_FILE_DEFAULT_SECTION};//! Merge settings from multiple sources in precedence order://! Forced config > command line > read-write settings file > config file network-specific section > config file default section//!//! This function is provided with a callback function fn that contains//! specific logic for how to merge the sources.template <typename Fn>static void MergeSettings(const Settings& settings, const std::string& section, const std::string& name, Fn&& fn){    // Merge in the forced settings    if (auto* value = FindKey(settings.forced_settings, name)) {        fn(SettingsSpan(*value), Source::FORCED);    }    // Merge in the command-line options    if (auto* values = FindKey(settings.command_line_options, name)) {        fn(SettingsSpan(*values), Source::COMMAND_LINE);    }    // Merge in the read-write settings    if (const SettingsValue* value = FindKey(settings.rw_settings, name)) {        fn(SettingsSpan(*value), Source::RW_SETTINGS);    }    // Merge in the network-specific section of the config file    if (!section.empty()) {        if (auto* map = FindKey(settings.ro_config, section)) {            if (auto* values = FindKey(*map, name)) {                fn(SettingsSpan(*values), Source::CONFIG_FILE_NETWORK_SECTION);            }        }    }    // Merge in the default section of the config file    if (auto* map = FindKey(settings.ro_config, "")) {        if (auto* values = FindKey(*map, name)) {            fn(SettingsSpan(*values), Source::CONFIG_FILE_DEFAULT_SECTION);        }    }}} // namespacebool ReadSettings(const fs::path& path, std::map<std::string, SettingsValue>& values, std::vector<std::string>& errors){    values.clear();    errors.clear();    fsbridge::ifstream file;    file.open(path);    if (!file.is_open()) return true; // Ok for file not to exist.    SettingsValue in;    if (!in.read(std::string{std::istreambuf_iterator<char>(file), std::istreambuf_iterator<char>()})) {        errors.emplace_back(strprintf("Unable to parse settings file %s", path.string()));        return false;    }    if (file.fail()) {        errors.emplace_back(strprintf("Failed reading settings file %s", path.string()));        return false;    }    file.close(); // Done with file descriptor. Release while copying data.    if (!in.isObject()) {        errors.emplace_back(strprintf("Found non-object value %s in settings file %s", in.write(), path.string()));        return false;    }    const std::vector<std::string>& in_keys = in.getKeys();    const std::vector<SettingsValue>& in_values = in.getValues();    for (size_t i = 0; i < in_keys.size(); ++i) {        auto inserted = values.emplace(in_keys[i], in_values[i]);        if (!inserted.second) {            errors.emplace_back(strprintf("Found duplicate key %s in settings file %s", in_keys[i], path.string()));        }    }    return errors.empty();}bool WriteSettings(const fs::path& path,    const std::map<std::string, SettingsValue>& values,    std::vector<std::string>& errors){    SettingsValue out(SettingsValue::VOBJ);    for (const auto& value : values) {        out.__pushKV(value.first, value.second);    }    fsbridge::ofstream file;    file.open(path);    if (file.fail()) {        errors.emplace_back(strprintf("Error: Unable to open settings file %s for writing", path.string()));        return false;    }    file << out.write(/* prettyIndent= */ 1, /* indentLevel= */ 4) << std::endl;    file.close();    return true;}SettingsValue GetSetting(const Settings& settings,    const std::string& section,    const std::string& name,    bool ignore_default_section_config,    bool get_chain_name){    SettingsValue result;    bool done = false; // Done merging any more settings sources.    MergeSettings(settings, section, name, [&](SettingsSpan span, Source source) {        // Weird behavior preserved for backwards compatibility: Apply negated        // setting even if non-negated setting would be ignored. A negated        // value in the default section is applied to network specific options,        // even though normal non-negated values there would be ignored.        const bool never_ignore_negated_setting = span.last_negated();        // Weird behavior preserved for backwards compatibility: Take first        // assigned value instead of last. In general, later settings take        // precedence over early settings, but for backwards compatibility in        // the config file the precedence is reversed for all settings except        // chain name settings.        const bool reverse_precedence =            (source == Source::CONFIG_FILE_NETWORK_SECTION || source == Source::CONFIG_FILE_DEFAULT_SECTION) &&            !get_chain_name;        // Weird behavior preserved for backwards compatibility: Negated        // -regtest and -testnet arguments which you would expect to override        // values set in the configuration file are currently accepted but        // silently ignored. It would be better to apply these just like other        // negated values, or at least warn they are ignored.        const bool skip_negated_command_line = get_chain_name;        if (done) return;        // Ignore settings in default config section if requested.        if (ignore_default_section_config && source == Source::CONFIG_FILE_DEFAULT_SECTION &&            !never_ignore_negated_setting) {            return;        }        // Skip negated command line settings.        if (skip_negated_command_line && span.last_negated()) return;        if (!span.empty()) {            result = reverse_precedence ? span.begin()[0] : span.end()[-1];            done = true;        } else if (span.last_negated()) {            result = false;            done = true;        }    });    return result;}std::vector<SettingsValue> GetSettingsList(const Settings& settings,    const std::string& section,    const std::string& name,    bool ignore_default_section_config){    std::vector<SettingsValue> result;    bool done = false; // Done merging any more settings sources.    bool prev_negated_empty = false;    MergeSettings(settings, section, name, [&](SettingsSpan span, Source source) {        // Weird behavior preserved for backwards compatibility: Apply config        // file settings even if negated on command line. Negating a setting on        // command line will ignore earlier settings on the command line and        // ignore settings in the config file, unless the negated command line        // value is followed by non-negated value, in which case config file        // settings will be brought back from the dead (but earlier command        // line settings will still be ignored).        const bool add_zombie_config_values =            (source == Source::CONFIG_FILE_NETWORK_SECTION || source == Source::CONFIG_FILE_DEFAULT_SECTION) &&            !prev_negated_empty;        // Ignore settings in default config section if requested.        if (ignore_default_section_config && source == Source::CONFIG_FILE_DEFAULT_SECTION) return;        // Add new settings to the result if isn't already complete, or if the        // values are zombies.        if (!done || add_zombie_config_values) {            for (const auto& value : span) {                if (value.isArray()) {                    result.insert(result.end(), value.getValues().begin(), value.getValues().end());                } else {                    result.push_back(value);                }            }        }        // If a setting was negated, or if a setting was forced, set        // done to true to ignore any later lower priority settings.        done |= span.negated() > 0 || source == Source::FORCED;        // Update the negated and empty state used for the zombie values check.        prev_negated_empty |= span.last_negated() && result.empty();    });    return result;}bool OnlyHasDefaultSectionSetting(const Settings& settings, const std::string& section, const std::string& name){    bool has_default_section_setting = false;    bool has_other_setting = false;    MergeSettings(settings, section, name, [&](SettingsSpan span, Source source) {        if (span.empty()) return;        else if (source == Source::CONFIG_FILE_DEFAULT_SECTION) has_default_section_setting = true;        else has_other_setting = true;    });    // If a value is set in the default section and not explicitly overwritten by the    // user on the command line or in a different section, then we want to enable    // warnings about the value being ignored.    return has_default_section_setting && !has_other_setting;}SettingsSpan::SettingsSpan(const std::vector<SettingsValue>& vec) noexcept : SettingsSpan(vec.data(), vec.size()) {}const SettingsValue* SettingsSpan::begin() const { return data + negated(); }const SettingsValue* SettingsSpan::end() const { return data + size; }bool SettingsSpan::empty() const { return size == 0 || last_negated(); }bool SettingsSpan::last_negated() const { return size > 0 && data[size - 1].isFalse(); }size_t SettingsSpan::negated() const{    for (size_t i = size; i > 0; --i) {        if (data[i - 1].isFalse()) return i; // Return number of negated values (position of last false value)    }    return 0;}} // namespace util