fix/src/libutil/config.cc
regnat af99941279 Make experimental-features a proper type
Rather than having them plain strings scattered through the whole
codebase, create an enum containing all the known experimental features.

This means that
- Nix can now `warn` when an unkwown experimental feature is passed
  (making it much nicer to spot typos and spot deprecated features)
- It’s now easy to remove a feature altogether (once the feature isn’t
  experimental anymore or is dropped) by just removing the field for the
  enum and letting the compiler point us to all the now invalid usages
  of it.
2021-10-26 07:02:31 +02:00

448 lines
12 KiB
C++

#include "config.hh"
#include "args.hh"
#include "abstract-setting-to-json.hh"
#include "experimental-features.hh"
#include <nlohmann/json.hpp>
namespace nix {
bool Config::set(const std::string & name, const std::string & value)
{
bool append = false;
auto i = _settings.find(name);
if (i == _settings.end()) {
if (hasPrefix(name, "extra-")) {
i = _settings.find(std::string(name, 6));
if (i == _settings.end() || !i->second.setting->isAppendable())
return false;
append = true;
} else
return false;
}
i->second.setting->set(value, append);
i->second.setting->overridden = true;
return true;
}
void Config::addSetting(AbstractSetting * setting)
{
_settings.emplace(setting->name, Config::SettingData(false, setting));
for (auto & alias : setting->aliases)
_settings.emplace(alias, Config::SettingData(true, setting));
bool set = false;
auto i = unknownSettings.find(setting->name);
if (i != unknownSettings.end()) {
setting->set(i->second);
setting->overridden = true;
unknownSettings.erase(i);
set = true;
}
for (auto & alias : setting->aliases) {
auto i = unknownSettings.find(alias);
if (i != unknownSettings.end()) {
if (set)
warn("setting '%s' is set, but it's an alias of '%s' which is also set",
alias, setting->name);
else {
setting->set(i->second);
setting->overridden = true;
unknownSettings.erase(i);
set = true;
}
}
}
}
void AbstractConfig::warnUnknownSettings()
{
for (auto & s : unknownSettings)
warn("unknown setting '%s'", s.first);
}
void AbstractConfig::reapplyUnknownSettings()
{
auto unknownSettings2 = std::move(unknownSettings);
for (auto & s : unknownSettings2)
set(s.first, s.second);
}
void Config::getSettings(std::map<std::string, SettingInfo> & res, bool overriddenOnly)
{
for (auto & opt : _settings)
if (!opt.second.isAlias && (!overriddenOnly || opt.second.setting->overridden))
res.emplace(opt.first, SettingInfo{opt.second.setting->to_string(), opt.second.setting->description});
}
void AbstractConfig::applyConfig(const std::string & contents, const std::string & path) {
unsigned int pos = 0;
while (pos < contents.size()) {
string line;
while (pos < contents.size() && contents[pos] != '\n')
line += contents[pos++];
pos++;
string::size_type hash = line.find('#');
if (hash != string::npos)
line = string(line, 0, hash);
vector<string> tokens = tokenizeString<vector<string> >(line);
if (tokens.empty()) continue;
if (tokens.size() < 2)
throw UsageError("illegal configuration line '%1%' in '%2%'", line, path);
auto include = false;
auto ignoreMissing = false;
if (tokens[0] == "include")
include = true;
else if (tokens[0] == "!include") {
include = true;
ignoreMissing = true;
}
if (include) {
if (tokens.size() != 2)
throw UsageError("illegal configuration line '%1%' in '%2%'", line, path);
auto p = absPath(tokens[1], dirOf(path));
if (pathExists(p)) {
applyConfigFile(p);
} else if (!ignoreMissing) {
throw Error("file '%1%' included from '%2%' not found", p, path);
}
continue;
}
if (tokens[1] != "=")
throw UsageError("illegal configuration line '%1%' in '%2%'", line, path);
string name = tokens[0];
vector<string>::iterator i = tokens.begin();
advance(i, 2);
set(name, concatStringsSep(" ", Strings(i, tokens.end()))); // FIXME: slow
};
}
void AbstractConfig::applyConfigFile(const Path & path)
{
try {
string contents = readFile(path);
applyConfig(contents, path);
} catch (SysError &) { }
}
void Config::resetOverridden()
{
for (auto & s : _settings)
s.second.setting->overridden = false;
}
nlohmann::json Config::toJSON()
{
auto res = nlohmann::json::object();
for (auto & s : _settings)
if (!s.second.isAlias) {
res.emplace(s.first, s.second.setting->toJSON());
}
return res;
}
std::string Config::toKeyValue()
{
auto res = std::string();
for (auto & s : _settings)
if (!s.second.isAlias) {
res += fmt("%s = %s\n", s.first, s.second.setting->to_string());
}
return res;
}
void Config::convertToArgs(Args & args, const std::string & category)
{
for (auto & s : _settings)
if (!s.second.isAlias)
s.second.setting->convertToArg(args, category);
}
AbstractSetting::AbstractSetting(
const std::string & name,
const std::string & description,
const std::set<std::string> & aliases)
: name(name), description(stripIndentation(description)), aliases(aliases)
{
}
nlohmann::json AbstractSetting::toJSON()
{
return nlohmann::json(toJSONObject());
}
std::map<std::string, nlohmann::json> AbstractSetting::toJSONObject()
{
std::map<std::string, nlohmann::json> obj;
obj.emplace("description", description);
obj.emplace("aliases", aliases);
return obj;
}
void AbstractSetting::convertToArg(Args & args, const std::string & category)
{
}
template<typename T>
bool BaseSetting<T>::isAppendable()
{
return false;
}
template<typename T>
void BaseSetting<T>::convertToArg(Args & args, const std::string & category)
{
args.addFlag({
.longName = name,
.description = fmt("Set the `%s` setting.", name),
.category = category,
.labels = {"value"},
.handler = {[=](std::string s) { overridden = true; set(s); }},
});
if (isAppendable())
args.addFlag({
.longName = "extra-" + name,
.description = fmt("Append to the `%s` setting.", name),
.category = category,
.labels = {"value"},
.handler = {[=](std::string s) { overridden = true; set(s, true); }},
});
}
template<> void BaseSetting<std::string>::set(const std::string & str, bool append)
{
value = str;
}
template<> std::string BaseSetting<std::string>::to_string() const
{
return value;
}
template<typename T>
void BaseSetting<T>::set(const std::string & str, bool append)
{
static_assert(std::is_integral<T>::value, "Integer required.");
if (auto n = string2Int<T>(str))
value = *n;
else
throw UsageError("setting '%s' has invalid value '%s'", name, str);
}
template<typename T>
std::string BaseSetting<T>::to_string() const
{
static_assert(std::is_integral<T>::value, "Integer required.");
return std::to_string(value);
}
template<> void BaseSetting<bool>::set(const std::string & str, bool append)
{
if (str == "true" || str == "yes" || str == "1")
value = true;
else if (str == "false" || str == "no" || str == "0")
value = false;
else
throw UsageError("Boolean setting '%s' has invalid value '%s'", name, str);
}
template<> std::string BaseSetting<bool>::to_string() const
{
return value ? "true" : "false";
}
template<> void BaseSetting<bool>::convertToArg(Args & args, const std::string & category)
{
args.addFlag({
.longName = name,
.description = fmt("Enable the `%s` setting.", name),
.category = category,
.handler = {[=]() { override(true); }}
});
args.addFlag({
.longName = "no-" + name,
.description = fmt("Disable the `%s` setting.", name),
.category = category,
.handler = {[=]() { override(false); }}
});
}
template<> void BaseSetting<Strings>::set(const std::string & str, bool append)
{
auto ss = tokenizeString<Strings>(str);
if (!append) value.clear();
for (auto & s : ss) value.push_back(std::move(s));
}
template<> bool BaseSetting<Strings>::isAppendable()
{
return true;
}
template<> std::string BaseSetting<Strings>::to_string() const
{
return concatStringsSep(" ", value);
}
template<> void BaseSetting<StringSet>::set(const std::string & str, bool append)
{
if (!append) value.clear();
for (auto & s : tokenizeString<StringSet>(str))
value.insert(s);
}
template<> bool BaseSetting<StringSet>::isAppendable()
{
return true;
}
template<> std::string BaseSetting<StringSet>::to_string() const
{
return concatStringsSep(" ", value);
}
template<> void BaseSetting<std::set<ExperimentalFeature>>::set(const std::string & str, bool append)
{
if (!append) value.clear();
for (auto & s : tokenizeString<StringSet>(str)) {
auto thisXpFeature = parseExperimentalFeature(s);
if (thisXpFeature)
value.insert(thisXpFeature.value());
else
warn("Unknown experimental feature %s", s);
}
}
template<> bool BaseSetting<std::set<ExperimentalFeature>>::isAppendable()
{
return true;
}
template<> std::string BaseSetting<std::set<ExperimentalFeature>>::to_string() const
{
StringSet stringifiedXpFeatures;
for (auto & feature : value)
stringifiedXpFeatures.insert(std::string(showExperimentalFeature(feature)));
return concatStringsSep(" ", stringifiedXpFeatures);
}
template<> void BaseSetting<StringMap>::set(const std::string & str, bool append)
{
if (!append) value.clear();
for (auto & s : tokenizeString<Strings>(str)) {
auto eq = s.find_first_of('=');
if (std::string::npos != eq)
value.emplace(std::string(s, 0, eq), std::string(s, eq + 1));
// else ignored
}
}
template<> bool BaseSetting<StringMap>::isAppendable()
{
return true;
}
template<> std::string BaseSetting<StringMap>::to_string() const
{
Strings kvstrs;
std::transform(value.begin(), value.end(), back_inserter(kvstrs),
[&](auto kvpair){ return kvpair.first + "=" + kvpair.second; });
return concatStringsSep(" ", kvstrs);
}
template class BaseSetting<int>;
template class BaseSetting<unsigned int>;
template class BaseSetting<long>;
template class BaseSetting<unsigned long>;
template class BaseSetting<long long>;
template class BaseSetting<unsigned long long>;
template class BaseSetting<bool>;
template class BaseSetting<std::string>;
template class BaseSetting<Strings>;
template class BaseSetting<StringSet>;
template class BaseSetting<StringMap>;
template class BaseSetting<std::set<ExperimentalFeature>>;
void PathSetting::set(const std::string & str, bool append)
{
if (str == "") {
if (allowEmpty)
value = "";
else
throw UsageError("setting '%s' cannot be empty", name);
} else
value = canonPath(str);
}
bool GlobalConfig::set(const std::string & name, const std::string & value)
{
for (auto & config : *configRegistrations)
if (config->set(name, value)) return true;
unknownSettings.emplace(name, value);
return false;
}
void GlobalConfig::getSettings(std::map<std::string, SettingInfo> & res, bool overriddenOnly)
{
for (auto & config : *configRegistrations)
config->getSettings(res, overriddenOnly);
}
void GlobalConfig::resetOverridden()
{
for (auto & config : *configRegistrations)
config->resetOverridden();
}
nlohmann::json GlobalConfig::toJSON()
{
auto res = nlohmann::json::object();
for (auto & config : *configRegistrations)
res.update(config->toJSON());
return res;
}
std::string GlobalConfig::toKeyValue()
{
std::string res;
std::map<std::string, Config::SettingInfo> settings;
globalConfig.getSettings(settings);
for (auto & s : settings)
res += fmt("%s = %s\n", s.first, s.second.value);
return res;
}
void GlobalConfig::convertToArgs(Args & args, const std::string & category)
{
for (auto & config : *configRegistrations)
config->convertToArgs(args, category);
}
GlobalConfig globalConfig;
GlobalConfig::ConfigRegistrations * GlobalConfig::configRegistrations;
GlobalConfig::Register::Register(Config * config)
{
if (!configRegistrations)
configRegistrations = new ConfigRegistrations;
configRegistrations->emplace_back(config);
}
}