move-only: Extract common/args and common/config.cpp from util/system

This is an extraction of ArgsManager related functions from util/system
into their own common file.

Config file related functions are moved to common/config.cpp.

The background of this commit is an ongoing effort to decouple the
libbitcoinkernel library from the ArgsManager. The ArgsManager belongs
into the common library, since the kernel library should not depend on
it. See doc/design/libraries.md for more information on this rationale.

1 files changed, 823 insertions, 0 deletions

diff --git a/src/common/args.cpp b/src/common/args.cpp
new file mode 100644
index 0000000000..d29b8648bf
--- /dev/null
+++ b/src/common/args.cpp
@@ -0,0 +1,823 @@
+// Copyright (c) 2009-2010 Satoshi Nakamoto
+// Copyright (c) 2009-2022 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 <common/args.h>
+
+#include <chainparamsbase.h>
+#include <logging.h>
+#include <sync.h>
+#include <tinyformat.h>
+#include <univalue.h>
+#include <util/check.h>
+#include <util/fs.h>
+#include <util/fs_helpers.h>
+#include <util/settings.h>
+#include <util/strencodings.h>
+
+#ifdef WIN32
+#include <codecvt>    /* for codecvt_utf8_utf16 */
+#include <shellapi.h> /* for CommandLineToArgvW */
+#include <shlobj.h>   /* for CSIDL_APPDATA */
+#endif
+
+#include <algorithm>
+#include <cassert>
+#include <cstdint>
+#include <cstdlib>
+#include <cstring>
+#include <filesystem>
+#include <map>
+#include <optional>
+#include <stdexcept>
+#include <string>
+#include <utility>
+
+const char * const BITCOIN_CONF_FILENAME = "bitcoin.conf";
+const char * const BITCOIN_SETTINGS_FILENAME = "settings.json";
+
+ArgsManager gArgs;
+
+/**
+ * Interpret a string argument as a boolean.
+ *
+ * The definition of LocaleIndependentAtoi<int>() requires that non-numeric string values
+ * like "foo", return 0. This means that if a user unintentionally supplies a
+ * non-integer argument here, the return value is always false. This means that
+ * -foo=false does what the user probably expects, but -foo=true is well defined
+ * but does not do what they probably expected.
+ *
+ * The return value of LocaleIndependentAtoi<int>(...) is zero when given input not
+ * representable as an int.
+ *
+ * For a more extensive discussion of this topic (and a wide range of opinions
+ * on the Right Way to change this code), see PR12713.
+ */
+static bool InterpretBool(const std::string& strValue)
+{
+    if (strValue.empty())
+        return true;
+    return (LocaleIndependentAtoi<int>(strValue) != 0);
+}
+
+static std::string SettingName(const std::string& arg)
+{
+    return arg.size() > 0 && arg[0] == '-' ? arg.substr(1) : arg;
+}
+
+/**
+ * Parse "name", "section.name", "noname", "section.noname" settings keys.
+ *
+ * @note Where an option was negated can be later checked using the
+ * IsArgNegated() method. One use case for this is to have a way to disable
+ * options that are not normally boolean (e.g. using -nodebuglogfile to request
+ * that debug log output is not sent to any file at all).
+ */
+KeyInfo InterpretKey(std::string key)
+{
+    KeyInfo result;
+    // Split section name from key name for keys like "testnet.foo" or "regtest.bar"
+    size_t option_index = key.find('.');
+    if (option_index != std::string::npos) {
+        result.section = key.substr(0, option_index);
+        key.erase(0, option_index + 1);
+    }
+    if (key.substr(0, 2) == "no") {
+        key.erase(0, 2);
+        result.negated = true;
+    }
+    result.name = key;
+    return result;
+}
+
+/**
+ * Interpret settings value based on registered flags.
+ *
+ * @param[in]   key      key information to know if key was negated
+ * @param[in]   value    string value of setting to be parsed
+ * @param[in]   flags    ArgsManager registered argument flags
+ * @param[out]  error    Error description if settings value is not valid
+ *
+ * @return parsed settings value if it is valid, otherwise nullopt accompanied
+ * by a descriptive error string
+ */
+std::optional<util::SettingsValue> InterpretValue(const KeyInfo& key, const std::string* value,
+                                                  unsigned int flags, std::string& error)
+{
+    // Return negated settings as false values.
+    if (key.negated) {
+        if (flags & ArgsManager::DISALLOW_NEGATION) {
+            error = strprintf("Negating of -%s is meaningless and therefore forbidden", key.name);
+            return std::nullopt;
+        }
+        // Double negatives like -nofoo=0 are supported (but discouraged)
+        if (value && !InterpretBool(*value)) {
+            LogPrintf("Warning: parsed potentially confusing double-negative -%s=%s\n", key.name, *value);
+            return true;
+        }
+        return false;
+    }
+    if (!value && (flags & ArgsManager::DISALLOW_ELISION)) {
+        error = strprintf("Can not set -%s with no value. Please specify value with -%s=value.", key.name, key.name);
+        return std::nullopt;
+    }
+    return value ? *value : "";
+}
+
+// Define default constructor and destructor that are not inline, so code instantiating this class doesn't need to
+// #include class definitions for all members.
+// For example, m_settings has an internal dependency on univalue.
+ArgsManager::ArgsManager() = default;
+ArgsManager::~ArgsManager() = default;
+
+std::set<std::string> ArgsManager::GetUnsuitableSectionOnlyArgs() const
+{
+    std::set<std::string> unsuitables;
+
+    LOCK(cs_args);
+
+    // if there's no section selected, don't worry
+    if (m_network.empty()) return std::set<std::string> {};
+
+    // if it's okay to use the default section for this network, don't worry
+    if (m_network == CBaseChainParams::MAIN) return std::set<std::string> {};
+
+    for (const auto& arg : m_network_only_args) {
+        if (OnlyHasDefaultSectionSetting(m_settings, m_network, SettingName(arg))) {
+            unsuitables.insert(arg);
+        }
+    }
+    return unsuitables;
+}
+
+std::list<SectionInfo> ArgsManager::GetUnrecognizedSections() const
+{
+    // Section names to be recognized in the config file.
+    static const std::set<std::string> available_sections{
+        CBaseChainParams::REGTEST,
+        CBaseChainParams::SIGNET,
+        CBaseChainParams::TESTNET,
+        CBaseChainParams::MAIN
+    };
+
+    LOCK(cs_args);
+    std::list<SectionInfo> unrecognized = m_config_sections;
+    unrecognized.remove_if([](const SectionInfo& appeared){ return available_sections.find(appeared.m_name) != available_sections.end(); });
+    return unrecognized;
+}
+
+void ArgsManager::SelectConfigNetwork(const std::string& network)
+{
+    LOCK(cs_args);
+    m_network = network;
+}
+
+bool ArgsManager::ParseParameters(int argc, const char* const argv[], std::string& error)
+{
+    LOCK(cs_args);
+    m_settings.command_line_options.clear();
+
+    for (int i = 1; i < argc; i++) {
+        std::string key(argv[i]);
+
+#ifdef MAC_OSX
+        // At the first time when a user gets the "App downloaded from the
+        // internet" warning, and clicks the Open button, macOS passes
+        // a unique process serial number (PSN) as -psn_... command-line
+        // argument, which we filter out.
+        if (key.substr(0, 5) == "-psn_") continue;
+#endif
+
+        if (key == "-") break; //bitcoin-tx using stdin
+        std::optional<std::string> val;
+        size_t is_index = key.find('=');
+        if (is_index != std::string::npos) {
+            val = key.substr(is_index + 1);
+            key.erase(is_index);
+        }
+#ifdef WIN32
+        key = ToLower(key);
+        if (key[0] == '/')
+            key[0] = '-';
+#endif
+
+        if (key[0] != '-') {
+            if (!m_accept_any_command && m_command.empty()) {
+                // The first non-dash arg is a registered command
+                std::optional<unsigned int> flags = GetArgFlags(key);
+                if (!flags || !(*flags & ArgsManager::COMMAND)) {
+                    error = strprintf("Invalid command '%s'", argv[i]);
+                    return false;
+                }
+            }
+            m_command.push_back(key);
+            while (++i < argc) {
+                // The remaining args are command args
+                m_command.push_back(argv[i]);
+            }
+            break;
+        }
+
+        // Transform --foo to -foo
+        if (key.length() > 1 && key[1] == '-')
+            key.erase(0, 1);
+
+        // Transform -foo to foo
+        key.erase(0, 1);
+        KeyInfo keyinfo = InterpretKey(key);
+        std::optional<unsigned int> flags = GetArgFlags('-' + keyinfo.name);
+
+        // Unknown command line options and command line options with dot
+        // characters (which are returned from InterpretKey with nonempty
+        // section strings) are not valid.
+        if (!flags || !keyinfo.section.empty()) {
+            error = strprintf("Invalid parameter %s", argv[i]);
+            return false;
+        }
+
+        std::optional<util::SettingsValue> value = InterpretValue(keyinfo, val ? &*val : nullptr, *flags, error);
+        if (!value) return false;
+
+        m_settings.command_line_options[keyinfo.name].push_back(*value);
+    }
+
+    // we do not allow -includeconf from command line, only -noincludeconf
+    if (auto* includes = util::FindKey(m_settings.command_line_options, "includeconf")) {
+        const util::SettingsSpan values{*includes};
+        // Range may be empty if -noincludeconf was passed
+        if (!values.empty()) {
+            error = "-includeconf cannot be used from commandline; -includeconf=" + values.begin()->write();
+            return false; // pick first value as example
+        }
+    }
+    return true;
+}
+
+std::optional<unsigned int> ArgsManager::GetArgFlags(const std::string& name) const
+{
+    LOCK(cs_args);
+    for (const auto& arg_map : m_available_args) {
+        const auto search = arg_map.second.find(name);
+        if (search != arg_map.second.end()) {
+            return search->second.m_flags;
+        }
+    }
+    return std::nullopt;
+}
+
+fs::path ArgsManager::GetPathArg(std::string arg, const fs::path& default_value) const
+{
+    if (IsArgNegated(arg)) return fs::path{};
+    std::string path_str = GetArg(arg, "");
+    if (path_str.empty()) return default_value;
+    fs::path result = fs::PathFromString(path_str).lexically_normal();
+    // Remove trailing slash, if present.
+    return result.has_filename() ? result : result.parent_path();
+}
+
+const fs::path& ArgsManager::GetBlocksDirPath() const
+{
+    LOCK(cs_args);
+    fs::path& path = m_cached_blocks_path;
+
+    // Cache the path to avoid calling fs::create_directories on every call of
+    // this function
+    if (!path.empty()) return path;
+
+    if (IsArgSet("-blocksdir")) {
+        path = fs::absolute(GetPathArg("-blocksdir"));
+        if (!fs::is_directory(path)) {
+            path = "";
+            return path;
+        }
+    } else {
+        path = GetDataDirBase();
+    }
+
+    path /= fs::PathFromString(BaseParams().DataDir());
+    path /= "blocks";
+    fs::create_directories(path);
+    return path;
+}
+
+const fs::path& ArgsManager::GetDataDir(bool net_specific) const
+{
+    LOCK(cs_args);
+    fs::path& path = net_specific ? m_cached_network_datadir_path : m_cached_datadir_path;
+
+    // Used cached path if available
+    if (!path.empty()) return path;
+
+    const fs::path datadir{GetPathArg("-datadir")};
+    if (!datadir.empty()) {
+        path = fs::absolute(datadir);
+        if (!fs::is_directory(path)) {
+            path = "";
+            return path;
+        }
+    } else {
+        path = GetDefaultDataDir();
+    }
+
+    if (net_specific && !BaseParams().DataDir().empty()) {
+        path /= fs::PathFromString(BaseParams().DataDir());
+    }
+
+    return path;
+}
+
+void ArgsManager::ClearPathCache()
+{
+    LOCK(cs_args);
+
+    m_cached_datadir_path = fs::path();
+    m_cached_network_datadir_path = fs::path();
+    m_cached_blocks_path = fs::path();
+}
+
+std::optional<const ArgsManager::Command> ArgsManager::GetCommand() const
+{
+    Command ret;
+    LOCK(cs_args);
+    auto it = m_command.begin();
+    if (it == m_command.end()) {
+        // No command was passed
+        return std::nullopt;
+    }
+    if (!m_accept_any_command) {
+        // The registered command
+        ret.command = *(it++);
+    }
+    while (it != m_command.end()) {
+        // The unregistered command and args (if any)
+        ret.args.push_back(*(it++));
+    }
+    return ret;
+}
+
+std::vector<std::string> ArgsManager::GetArgs(const std::string& strArg) const
+{
+    std::vector<std::string> result;
+    for (const util::SettingsValue& value : GetSettingsList(strArg)) {
+        result.push_back(value.isFalse() ? "0" : value.isTrue() ? "1" : value.get_str());
+    }
+    return result;
+}
+
+bool ArgsManager::IsArgSet(const std::string& strArg) const
+{
+    return !GetSetting(strArg).isNull();
+}
+
+bool ArgsManager::GetSettingsPath(fs::path* filepath, bool temp, bool backup) const
+{
+    fs::path settings = GetPathArg("-settings", BITCOIN_SETTINGS_FILENAME);
+    if (settings.empty()) {
+        return false;
+    }
+    if (backup) {
+        settings += ".bak";
+    }
+    if (filepath) {
+        *filepath = fsbridge::AbsPathJoin(GetDataDirNet(), temp ? settings + ".tmp" : settings);
+    }
+    return true;
+}
+
+static void SaveErrors(const std::vector<std::string> errors, std::vector<std::string>* error_out)
+{
+    for (const auto& error : errors) {
+        if (error_out) {
+            error_out->emplace_back(error);
+        } else {
+            LogPrintf("%s\n", error);
+        }
+    }
+}
+
+bool ArgsManager::ReadSettingsFile(std::vector<std::string>* errors)
+{
+    fs::path path;
+    if (!GetSettingsPath(&path, /* temp= */ false)) {
+        return true; // Do nothing if settings file disabled.
+    }
+
+    LOCK(cs_args);
+    m_settings.rw_settings.clear();
+    std::vector<std::string> read_errors;
+    if (!util::ReadSettings(path, m_settings.rw_settings, read_errors)) {
+        SaveErrors(read_errors, errors);
+        return false;
+    }
+    for (const auto& setting : m_settings.rw_settings) {
+        KeyInfo key = InterpretKey(setting.first); // Split setting key into section and argname
+        if (!GetArgFlags('-' + key.name)) {
+            LogPrintf("Ignoring unknown rw_settings value %s\n", setting.first);
+        }
+    }
+    return true;
+}
+
+bool ArgsManager::WriteSettingsFile(std::vector<std::string>* errors, bool backup) const
+{
+    fs::path path, path_tmp;
+    if (!GetSettingsPath(&path, /*temp=*/false, backup) || !GetSettingsPath(&path_tmp, /*temp=*/true, backup)) {
+        throw std::logic_error("Attempt to write settings file when dynamic settings are disabled.");
+    }
+
+    LOCK(cs_args);
+    std::vector<std::string> write_errors;
+    if (!util::WriteSettings(path_tmp, m_settings.rw_settings, write_errors)) {
+        SaveErrors(write_errors, errors);
+        return false;
+    }
+    if (!RenameOver(path_tmp, path)) {
+        SaveErrors({strprintf("Failed renaming settings file %s to %s\n", fs::PathToString(path_tmp), fs::PathToString(path))}, errors);
+        return false;
+    }
+    return true;
+}
+
+util::SettingsValue ArgsManager::GetPersistentSetting(const std::string& name) const
+{
+    LOCK(cs_args);
+    return util::GetSetting(m_settings, m_network, name, !UseDefaultSection("-" + name),
+        /*ignore_nonpersistent=*/true, /*get_chain_name=*/false);
+}
+
+bool ArgsManager::IsArgNegated(const std::string& strArg) const
+{
+    return GetSetting(strArg).isFalse();
+}
+
+std::string ArgsManager::GetArg(const std::string& strArg, const std::string& strDefault) const
+{
+    return GetArg(strArg).value_or(strDefault);
+}
+
+std::optional<std::string> ArgsManager::GetArg(const std::string& strArg) const
+{
+    const util::SettingsValue value = GetSetting(strArg);
+    return SettingToString(value);
+}
+
+std::optional<std::string> SettingToString(const util::SettingsValue& value)
+{
+    if (value.isNull()) return std::nullopt;
+    if (value.isFalse()) return "0";
+    if (value.isTrue()) return "1";
+    if (value.isNum()) return value.getValStr();
+    return value.get_str();
+}
+
+std::string SettingToString(const util::SettingsValue& value, const std::string& strDefault)
+{
+    return SettingToString(value).value_or(strDefault);
+}
+
+int64_t ArgsManager::GetIntArg(const std::string& strArg, int64_t nDefault) const
+{
+    return GetIntArg(strArg).value_or(nDefault);
+}
+
+std::optional<int64_t> ArgsManager::GetIntArg(const std::string& strArg) const
+{
+    const util::SettingsValue value = GetSetting(strArg);
+    return SettingToInt(value);
+}
+
+std::optional<int64_t> SettingToInt(const util::SettingsValue& value)
+{
+    if (value.isNull()) return std::nullopt;
+    if (value.isFalse()) return 0;
+    if (value.isTrue()) return 1;
+    if (value.isNum()) return value.getInt<int64_t>();
+    return LocaleIndependentAtoi<int64_t>(value.get_str());
+}
+
+int64_t SettingToInt(const util::SettingsValue& value, int64_t nDefault)
+{
+    return SettingToInt(value).value_or(nDefault);
+}
+
+bool ArgsManager::GetBoolArg(const std::string& strArg, bool fDefault) const
+{
+    return GetBoolArg(strArg).value_or(fDefault);
+}
+
+std::optional<bool> ArgsManager::GetBoolArg(const std::string& strArg) const
+{
+    const util::SettingsValue value = GetSetting(strArg);
+    return SettingToBool(value);
+}
+
+std::optional<bool> SettingToBool(const util::SettingsValue& value)
+{
+    if (value.isNull()) return std::nullopt;
+    if (value.isBool()) return value.get_bool();
+    return InterpretBool(value.get_str());
+}
+
+bool SettingToBool(const util::SettingsValue& value, bool fDefault)
+{
+    return SettingToBool(value).value_or(fDefault);
+}
+
+bool ArgsManager::SoftSetArg(const std::string& strArg, const std::string& strValue)
+{
+    LOCK(cs_args);
+    if (IsArgSet(strArg)) return false;
+    ForceSetArg(strArg, strValue);
+    return true;
+}
+
+bool ArgsManager::SoftSetBoolArg(const std::string& strArg, bool fValue)
+{
+    if (fValue)
+        return SoftSetArg(strArg, std::string("1"));
+    else
+        return SoftSetArg(strArg, std::string("0"));
+}
+
+void ArgsManager::ForceSetArg(const std::string& strArg, const std::string& strValue)
+{
+    LOCK(cs_args);
+    m_settings.forced_settings[SettingName(strArg)] = strValue;
+}
+
+void ArgsManager::AddCommand(const std::string& cmd, const std::string& help)
+{
+    Assert(cmd.find('=') == std::string::npos);
+    Assert(cmd.at(0) != '-');
+
+    LOCK(cs_args);
+    m_accept_any_command = false; // latch to false
+    std::map<std::string, Arg>& arg_map = m_available_args[OptionsCategory::COMMANDS];
+    auto ret = arg_map.emplace(cmd, Arg{"", help, ArgsManager::COMMAND});
+    Assert(ret.second); // Fail on duplicate commands
+}
+
+void ArgsManager::AddArg(const std::string& name, const std::string& help, unsigned int flags, const OptionsCategory& cat)
+{
+    Assert((flags & ArgsManager::COMMAND) == 0); // use AddCommand
+
+    // Split arg name from its help param
+    size_t eq_index = name.find('=');
+    if (eq_index == std::string::npos) {
+        eq_index = name.size();
+    }
+    std::string arg_name = name.substr(0, eq_index);
+
+    LOCK(cs_args);
+    std::map<std::string, Arg>& arg_map = m_available_args[cat];
+    auto ret = arg_map.emplace(arg_name, Arg{name.substr(eq_index, name.size() - eq_index), help, flags});
+    assert(ret.second); // Make sure an insertion actually happened
+
+    if (flags & ArgsManager::NETWORK_ONLY) {
+        m_network_only_args.emplace(arg_name);
+    }
+}
+
+void ArgsManager::AddHiddenArgs(const std::vector<std::string>& names)
+{
+    for (const std::string& name : names) {
+        AddArg(name, "", ArgsManager::ALLOW_ANY, OptionsCategory::HIDDEN);
+    }
+}
+
+std::string ArgsManager::GetHelpMessage() const
+{
+    const bool show_debug = GetBoolArg("-help-debug", false);
+
+    std::string usage;
+    LOCK(cs_args);
+    for (const auto& arg_map : m_available_args) {
+        switch(arg_map.first) {
+            case OptionsCategory::OPTIONS:
+                usage += HelpMessageGroup("Options:");
+                break;
+            case OptionsCategory::CONNECTION:
+                usage += HelpMessageGroup("Connection options:");
+                break;
+            case OptionsCategory::ZMQ:
+                usage += HelpMessageGroup("ZeroMQ notification options:");
+                break;
+            case OptionsCategory::DEBUG_TEST:
+                usage += HelpMessageGroup("Debugging/Testing options:");
+                break;
+            case OptionsCategory::NODE_RELAY:
+                usage += HelpMessageGroup("Node relay options:");
+                break;
+            case OptionsCategory::BLOCK_CREATION:
+                usage += HelpMessageGroup("Block creation options:");
+                break;
+            case OptionsCategory::RPC:
+                usage += HelpMessageGroup("RPC server options:");
+                break;
+            case OptionsCategory::WALLET:
+                usage += HelpMessageGroup("Wallet options:");
+                break;
+            case OptionsCategory::WALLET_DEBUG_TEST:
+                if (show_debug) usage += HelpMessageGroup("Wallet debugging/testing options:");
+                break;
+            case OptionsCategory::CHAINPARAMS:
+                usage += HelpMessageGroup("Chain selection options:");
+                break;
+            case OptionsCategory::GUI:
+                usage += HelpMessageGroup("UI Options:");
+                break;
+            case OptionsCategory::COMMANDS:
+                usage += HelpMessageGroup("Commands:");
+                break;
+            case OptionsCategory::REGISTER_COMMANDS:
+                usage += HelpMessageGroup("Register Commands:");
+                break;
+            default:
+                break;
+        }
+
+        // When we get to the hidden options, stop
+        if (arg_map.first == OptionsCategory::HIDDEN) break;
+
+        for (const auto& arg : arg_map.second) {
+            if (show_debug || !(arg.second.m_flags & ArgsManager::DEBUG_ONLY)) {
+                std::string name;
+                if (arg.second.m_help_param.empty()) {
+                    name = arg.first;
+                } else {
+                    name = arg.first + arg.second.m_help_param;
+                }
+                usage += HelpMessageOpt(name, arg.second.m_help_text);
+            }
+        }
+    }
+    return usage;
+}
+
+bool HelpRequested(const ArgsManager& args)
+{
+    return args.IsArgSet("-?") || args.IsArgSet("-h") || args.IsArgSet("-help") || args.IsArgSet("-help-debug");
+}
+
+void SetupHelpOptions(ArgsManager& args)
+{
+    args.AddArg("-?", "Print this help message and exit", ArgsManager::ALLOW_ANY, OptionsCategory::OPTIONS);
+    args.AddHiddenArgs({"-h", "-help"});
+}
+
+static const int screenWidth = 79;
+static const int optIndent = 2;
+static const int msgIndent = 7;
+
+std::string HelpMessageGroup(const std::string &message) {
+    return std::string(message) + std::string("\n\n");
+}
+
+std::string HelpMessageOpt(const std::string &option, const std::string &message) {
+    return std::string(optIndent,' ') + std::string(option) +
+           std::string("\n") + std::string(msgIndent,' ') +
+           FormatParagraph(message, screenWidth - msgIndent, msgIndent) +
+           std::string("\n\n");
+}
+
+fs::path GetDefaultDataDir()
+{
+    // Windows: C:\Users\Username\AppData\Roaming\Bitcoin
+    // macOS: ~/Library/Application Support/Bitcoin
+    // Unix-like: ~/.bitcoin
+#ifdef WIN32
+    // Windows
+    return GetSpecialFolderPath(CSIDL_APPDATA) / "Bitcoin";
+#else
+    fs::path pathRet;
+    char* pszHome = getenv("HOME");
+    if (pszHome == nullptr || strlen(pszHome) == 0)
+        pathRet = fs::path("/");
+    else
+        pathRet = fs::path(pszHome);
+#ifdef MAC_OSX
+    // macOS
+    return pathRet / "Library/Application Support/Bitcoin";
+#else
+    // Unix-like
+    return pathRet / ".bitcoin";
+#endif
+#endif
+}
+
+bool CheckDataDirOption(const ArgsManager& args)
+{
+    const fs::path datadir{args.GetPathArg("-datadir")};
+    return datadir.empty() || fs::is_directory(fs::absolute(datadir));
+}
+
+fs::path ArgsManager::GetConfigFilePath() const
+{
+    return GetConfigFile(*this, GetPathArg("-conf", BITCOIN_CONF_FILENAME));
+}
+
+std::string ArgsManager::GetChainName() const
+{
+    auto get_net = [&](const std::string& arg) {
+        LOCK(cs_args);
+        util::SettingsValue value = util::GetSetting(m_settings, /* section= */ "", SettingName(arg),
+            /* ignore_default_section_config= */ false,
+            /*ignore_nonpersistent=*/false,
+            /* get_chain_name= */ true);
+        return value.isNull() ? false : value.isBool() ? value.get_bool() : InterpretBool(value.get_str());
+    };
+
+    const bool fRegTest = get_net("-regtest");
+    const bool fSigNet  = get_net("-signet");
+    const bool fTestNet = get_net("-testnet");
+    const bool is_chain_arg_set = IsArgSet("-chain");
+
+    if ((int)is_chain_arg_set + (int)fRegTest + (int)fSigNet + (int)fTestNet > 1) {
+        throw std::runtime_error("Invalid combination of -regtest, -signet, -testnet and -chain. Can use at most one.");
+    }
+    if (fRegTest)
+        return CBaseChainParams::REGTEST;
+    if (fSigNet) {
+        return CBaseChainParams::SIGNET;
+    }
+    if (fTestNet)
+        return CBaseChainParams::TESTNET;
+
+    return GetArg("-chain", CBaseChainParams::MAIN);
+}
+
+bool ArgsManager::UseDefaultSection(const std::string& arg) const
+{
+    return m_network == CBaseChainParams::MAIN || m_network_only_args.count(arg) == 0;
+}
+
+util::SettingsValue ArgsManager::GetSetting(const std::string& arg) const
+{
+    LOCK(cs_args);
+    return util::GetSetting(
+        m_settings, m_network, SettingName(arg), !UseDefaultSection(arg),
+        /*ignore_nonpersistent=*/false, /*get_chain_name=*/false);
+}
+
+std::vector<util::SettingsValue> ArgsManager::GetSettingsList(const std::string& arg) const
+{
+    LOCK(cs_args);
+    return util::GetSettingsList(m_settings, m_network, SettingName(arg), !UseDefaultSection(arg));
+}
+
+void ArgsManager::logArgsPrefix(
+    const std::string& prefix,
+    const std::string& section,
+    const std::map<std::string, std::vector<util::SettingsValue>>& args) const
+{
+    std::string section_str = section.empty() ? "" : "[" + section + "] ";
+    for (const auto& arg : args) {
+        for (const auto& value : arg.second) {
+            std::optional<unsigned int> flags = GetArgFlags('-' + arg.first);
+            if (flags) {
+                std::string value_str = (*flags & SENSITIVE) ? "****" : value.write();
+                LogPrintf("%s %s%s=%s\n", prefix, section_str, arg.first, value_str);
+            }
+        }
+    }
+}
+
+void ArgsManager::LogArgs() const
+{
+    LOCK(cs_args);
+    for (const auto& section : m_settings.ro_config) {
+        logArgsPrefix("Config file arg:", section.first, section.second);
+    }
+    for (const auto& setting : m_settings.rw_settings) {
+        LogPrintf("Setting file arg: %s = %s\n", setting.first, setting.second.write());
+    }
+    logArgsPrefix("Command-line arg:", "", m_settings.command_line_options);
+}
+
+namespace common {
+#ifdef WIN32
+WinCmdLineArgs::WinCmdLineArgs()
+{
+    wchar_t** wargv = CommandLineToArgvW(GetCommandLineW(), &argc);
+    std::wstring_convert<std::codecvt_utf8_utf16<wchar_t>, wchar_t> utf8_cvt;
+    argv = new char*[argc];
+    args.resize(argc);
+    for (int i = 0; i < argc; i++) {
+        args[i] = utf8_cvt.to_bytes(wargv[i]);
+        argv[i] = &*args[i].begin();
+    }
+    LocalFree(wargv);
+}
+
+WinCmdLineArgs::~WinCmdLineArgs()
+{
+    delete[] argv;
+}
+
+std::pair<int, char**> WinCmdLineArgs::get()
+{
+    return std::make_pair(argc, argv);
+}
+#endif
+} // namespace common