diff options
Diffstat (limited to 'nixos/modules/installer/tools')
7 files changed, 730 insertions, 331 deletions
diff --git a/nixos/modules/installer/tools/nixos-option.sh b/nixos/modules/installer/tools/nixos-option.sh deleted file mode 100644 index 4560e9c7403..00000000000 --- a/nixos/modules/installer/tools/nixos-option.sh +++ /dev/null @@ -1,327 +0,0 @@ -#! @shell@ -e - -# FIXME: rewrite this in a more suitable language. - -usage () { - exec man nixos-option - exit 1 -} - -##################### -# Process Arguments # -##################### - -xml=false -verbose=false -nixPath="" - -option="" -exit_code=0 - -argfun="" -for arg; do - if test -z "$argfun"; then - case $arg in - -*) - sarg="$arg" - longarg="" - while test "$sarg" != "-"; do - case $sarg in - --*) longarg=$arg; sarg="--";; - -I) argfun="include_nixpath";; - -*) usage;; - esac - # remove the first letter option - sarg="-${sarg#??}" - done - ;; - *) longarg=$arg;; - esac - for larg in $longarg; do - case $larg in - --xml) xml=true;; - --verbose) verbose=true;; - --help) usage;; - -*) usage;; - *) if test -z "$option"; then - option="$larg" - else - usage - fi;; - esac - done - else - case $argfun in - set_*) - var=$(echo $argfun | sed 's,^set_,,') - eval $var=$arg - ;; - include_nixpath) - nixPath="-I $arg $nixPath" - ;; - esac - argfun="" - fi -done - -if $verbose; then - set -x -else - set +x -fi - -############################# -# Process the configuration # -############################# - -evalNix(){ - # disable `-e` flag, it's possible that the evaluation of `nix-instantiate` fails (e.g. due to broken pkgs) - set +e - result=$(nix-instantiate ${nixPath:+$nixPath} - --eval-only "$@" 2>&1) - exit_code=$? - set -e - - if test $exit_code -eq 0; then - sed '/^warning: Nix search path/d' <<EOF -$result -EOF - return 0; - else - sed -n ' - /^error/ { s/, at (string):[0-9]*:[0-9]*//; p; }; - /^warning: Nix search path/ { p; }; -' >&2 <<EOF -$result -EOF - exit_code=1 - fi -} - -header="let - nixos = import <nixpkgs/nixos> {}; - nixpkgs = import <nixpkgs> {}; -in with nixpkgs.lib; -" - -# This function is used for converting the option definition path given by -# the user into accessors for reaching the definition and the declaration -# corresponding to this option. -generateAccessors(){ - if result=$(evalNix --strict --show-trace <<EOF -$header - -let - path = "${option:+$option}"; - pathList = splitString "." path; - - walkOptions = attrsNames: result: - if attrsNames == [] then - result - else - let name = head attrsNames; rest = tail attrsNames; in - if isOption result.options then - walkOptions rest { - options = result.options.type.getSubOptions ""; - opt = ''(\${result.opt}.type.getSubOptions "")''; - cfg = ''\${result.cfg}."\${name}"''; - } - else - walkOptions rest { - options = result.options.\${name}; - opt = ''\${result.opt}."\${name}"''; - cfg = ''\${result.cfg}."\${name}"''; - } - ; - - walkResult = (if path == "" then x: x else walkOptions pathList) { - options = nixos.options; - opt = ''nixos.options''; - cfg = ''nixos.config''; - }; - -in - ''let option = \${walkResult.opt}; config = \${walkResult.cfg}; in'' -EOF -) - then - echo $result - else - # In case of error we want to ignore the error message roduced by the - # script above, as it is iterating over each attribute, which does not - # produce a nice error message. The following code is a fallback - # solution which is cause a nicer error message in the next - # evaluation. - echo "\"let option = nixos.options${option:+.$option}; config = nixos.config${option:+.$option}; in\"" - fi -} - -header="$header -$(eval echo $(generateAccessors)) -" - -evalAttr(){ - local prefix="$1" - local strict="$2" - local suffix="$3" - - # If strict is set, then set it to "true". - test -n "$strict" && strict=true - - evalNix ${strict:+--strict} <<EOF -$header - -let - value = $prefix${suffix:+.$suffix}; - strict = ${strict:-false}; - cleanOutput = x: with nixpkgs.lib; - if isDerivation x then x.outPath - else if isFunction x then "<CODE>" - else if strict then - if isAttrs x then mapAttrs (n: cleanOutput) x - else if isList x then map cleanOutput x - else x - else x; -in - cleanOutput value -EOF -} - -evalOpt(){ - evalAttr "option" "" "$@" -} - -evalCfg(){ - local strict="$1" - evalAttr "config" "$strict" -} - -findSources(){ - local suffix=$1 - evalNix --strict <<EOF -$header - -option.$suffix -EOF -} - -# Given a result from nix-instantiate, recover the list of attributes it -# contains. -attrNames() { - local attributeset=$1 - # sed is used to replace un-printable subset by 0s, and to remove most of - # the inner-attribute set, which reduce the likelyhood to encounter badly - # pre-processed input. - echo "builtins.attrNames $attributeset" | \ - sed 's,<[A-Z]*>,0,g; :inner; s/{[^\{\}]*};/0;/g; t inner;' | \ - evalNix --strict -} - -# map a simple list which contains strings or paths. -nixMap() { - local fun="$1" - local list="$2" - local elem - for elem in $list; do - test $elem = '[' -o $elem = ']' && continue; - $fun $elem - done -} - -# This duplicates the work made below, but it is useful for processing -# the output of nixos-option with other tools such as nixos-gui. -if $xml; then - evalNix --xml --no-location <<EOF -$header - -let - sources = builtins.map (f: f.source); - opt = option; - cfg = config; -in - -with nixpkgs.lib; - -let - optStrict = v: - let - traverse = x : - if isAttrs x then - if x ? outPath then true - else all id (mapAttrsFlatten (n: traverseNoAttrs) x) - else traverseNoAttrs x; - traverseNoAttrs = x: - # do not continue in attribute sets - if isAttrs x then true - else if isList x then all id (map traverse x) - else true; - in assert traverse v; v; -in - -if isOption opt then - optStrict ({} - // optionalAttrs (opt ? default) { inherit (opt) default; } - // optionalAttrs (opt ? example) { inherit (opt) example; } - // optionalAttrs (opt ? description) { inherit (opt) description; } - // optionalAttrs (opt ? type) { typename = opt.type.description; } - // optionalAttrs (opt ? options) { inherit (opt) options; } - // { - # to disambiguate the xml output. - _isOption = true; - declarations = sources opt.declarations; - definitions = sources opt.definitions; - value = cfg; - }) -else - opt -EOF - exit $? -fi - -if test "$(evalOpt "_type" 2> /dev/null)" = '"option"'; then - echo "Value:" - evalCfg 1 - - echo - - echo "Default:" - if default=$(evalOpt "default" - 2> /dev/null); then - echo "$default" - else - echo "<None>" - fi - echo - if example=$(evalOpt "example" - 2> /dev/null); then - echo "Example:" - echo "$example" - echo - fi - echo "Description:" - echo - echo $(evalOpt "description") - - echo $desc; - - printPath () { echo " $1"; } - - echo "Declared by:" - nixMap printPath "$(findSources "declarations")" - echo - echo "Defined by:" - nixMap printPath "$(findSources "files")" - echo - -else - # echo 1>&2 "Warning: This value is not an option." - - result=$(evalCfg "") - if [ ! -z "$result" ]; then - names=$(attrNames "$result" 2> /dev/null) - echo 1>&2 "This attribute set contains:" - escapeQuotes () { eval echo "$1"; } - nixMap escapeQuotes "$names" - else - echo 1>&2 "An error occurred while looking for attribute names. Are you sure that '$option' exists?" - fi -fi - -exit $exit_code diff --git a/nixos/modules/installer/tools/nixos-option/CMakeLists.txt b/nixos/modules/installer/tools/nixos-option/CMakeLists.txt new file mode 100644 index 00000000000..e5834598c4f --- /dev/null +++ b/nixos/modules/installer/tools/nixos-option/CMakeLists.txt @@ -0,0 +1,8 @@ +cmake_minimum_required (VERSION 2.6) +project (nixos-option) + +add_executable(nixos-option nixos-option.cc libnix-copy-paste.cc) +target_link_libraries(nixos-option PRIVATE -lnixmain -lnixexpr -lnixstore -lnixutil) +target_compile_features(nixos-option PRIVATE cxx_std_17) + +install (TARGETS nixos-option DESTINATION bin) diff --git a/nixos/modules/installer/tools/nixos-option/default.nix b/nixos/modules/installer/tools/nixos-option/default.nix new file mode 100644 index 00000000000..753fd92c7bb --- /dev/null +++ b/nixos/modules/installer/tools/nixos-option/default.nix @@ -0,0 +1,11 @@ +{lib, stdenv, boost, cmake, pkgconfig, nix, ... }: +stdenv.mkDerivation rec { + name = "nixos-option"; + src = ./.; + nativeBuildInputs = [ cmake pkgconfig ]; + buildInputs = [ boost nix ]; + meta = { + license = stdenv.lib.licenses.lgpl2Plus; + maintainers = with lib.maintainers; [ chkno ]; + }; +} diff --git a/nixos/modules/installer/tools/nixos-option/libnix-copy-paste.cc b/nixos/modules/installer/tools/nixos-option/libnix-copy-paste.cc new file mode 100644 index 00000000000..875c07da639 --- /dev/null +++ b/nixos/modules/installer/tools/nixos-option/libnix-copy-paste.cc @@ -0,0 +1,83 @@ +// These are useful methods inside the nix library that ought to be exported. +// Since they are not, copy/paste them here. +// TODO: Delete these and use the ones in the library as they become available. + +#include <nix/config.h> // for nix/globals.hh's reference to SYSTEM + +#include "libnix-copy-paste.hh" +#include <boost/format/alt_sstream.hpp> // for basic_altstringbuf... +#include <boost/format/alt_sstream_impl.hpp> // for basic_altstringbuf... +#include <boost/format/format_class.hpp> // for basic_format +#include <boost/format/format_fwd.hpp> // for format +#include <boost/format/format_implementation.hpp> // for basic_format::basi... +#include <boost/optional/optional.hpp> // for get_pointer +#include <iostream> // for operator<<, basic_... +#include <nix/types.hh> // for Strings, Error +#include <string> // for string, basic_string + +using boost::format; +using nix::Error; +using nix::Strings; +using std::string; + +// From nix/src/libexpr/attr-path.cc +Strings parseAttrPath(const string & s) +{ + Strings res; + string cur; + string::const_iterator i = s.begin(); + while (i != s.end()) { + if (*i == '.') { + res.push_back(cur); + cur.clear(); + } else if (*i == '"') { + ++i; + while (1) { + if (i == s.end()) + throw Error(format("missing closing quote in selection path '%1%'") % s); + if (*i == '"') + break; + cur.push_back(*i++); + } + } else + cur.push_back(*i); + ++i; + } + if (!cur.empty()) + res.push_back(cur); + return res; +} + +// From nix/src/nix/repl.cc +bool isVarName(const string & s) +{ + if (s.size() == 0) + return false; + char c = s[0]; + if ((c >= '0' && c <= '9') || c == '-' || c == '\'') + return false; + for (auto & i : s) + if (!((i >= 'a' && i <= 'z') || (i >= 'A' && i <= 'Z') || (i >= '0' && i <= '9') || i == '_' || i == '-' || + i == '\'')) + return false; + return true; +} + +// From nix/src/nix/repl.cc +std::ostream & printStringValue(std::ostream & str, const char * string) +{ + str << "\""; + for (const char * i = string; *i; i++) + if (*i == '\"' || *i == '\\') + str << "\\" << *i; + else if (*i == '\n') + str << "\\n"; + else if (*i == '\r') + str << "\\r"; + else if (*i == '\t') + str << "\\t"; + else + str << *i; + str << "\""; + return str; +} diff --git a/nixos/modules/installer/tools/nixos-option/libnix-copy-paste.hh b/nixos/modules/installer/tools/nixos-option/libnix-copy-paste.hh new file mode 100644 index 00000000000..2274e9a0f85 --- /dev/null +++ b/nixos/modules/installer/tools/nixos-option/libnix-copy-paste.hh @@ -0,0 +1,9 @@ +#pragma once + +#include <iostream> +#include <nix/types.hh> +#include <string> + +nix::Strings parseAttrPath(const std::string & s); +bool isVarName(const std::string & s); +std::ostream & printStringValue(std::ostream & str, const char * string); diff --git a/nixos/modules/installer/tools/nixos-option/nixos-option.cc b/nixos/modules/installer/tools/nixos-option/nixos-option.cc new file mode 100644 index 00000000000..9b92dc829cd --- /dev/null +++ b/nixos/modules/installer/tools/nixos-option/nixos-option.cc @@ -0,0 +1,618 @@ +#include <nix/config.h> // for nix/globals.hh's reference to SYSTEM + +#include <exception> // for exception_ptr, current_exception +#include <functional> // for function +#include <iostream> // for operator<<, basic_ostream, ostrin... +#include <iterator> // for next +#include <list> // for _List_iterator +#include <memory> // for allocator, unique_ptr, make_unique +#include <new> // for operator new +#include <nix/args.hh> // for argvToStrings, UsageError +#include <nix/attr-path.hh> // for findAlongAttrPath +#include <nix/attr-set.hh> // for Attr, Bindings, Bindings::iterator +#include <nix/common-eval-args.hh> // for MixEvalArgs +#include <nix/eval-inline.hh> // for EvalState::forceValue +#include <nix/eval.hh> // for EvalState, initGC, operator<< +#include <nix/globals.hh> // for initPlugins, Settings, settings +#include <nix/nixexpr.hh> // for Pos +#include <nix/shared.hh> // for getArg, LegacyArgs, printVersion +#include <nix/store-api.hh> // for openStore +#include <nix/symbol-table.hh> // for Symbol, SymbolTable +#include <nix/types.hh> // for Error, Path, Strings, PathSet +#include <nix/util.hh> // for absPath, baseNameOf +#include <nix/value.hh> // for Value, Value::(anonymous), Value:... +#include <string> // for string, operator+, operator== +#include <utility> // for move +#include <variant> // for get, holds_alternative, variant +#include <vector> // for vector<>::iterator, vector + +#include "libnix-copy-paste.hh" + +using nix::absPath; +using nix::Bindings; +using nix::Error; +using nix::EvalError; +using nix::EvalState; +using nix::Path; +using nix::PathSet; +using nix::Strings; +using nix::Symbol; +using nix::tAttrs; +using nix::ThrownError; +using nix::tLambda; +using nix::tString; +using nix::UsageError; +using nix::Value; + +// An ostream wrapper to handle nested indentation +class Out +{ + public: + class Separator + {}; + const static Separator sep; + enum LinePolicy + { + ONE_LINE, + MULTI_LINE + }; + explicit Out(std::ostream & ostream) : ostream(ostream), policy(ONE_LINE), writeSinceSep(true) {} + Out(Out & o, const std::string & start, const std::string & end, LinePolicy policy); + Out(Out & o, const std::string & start, const std::string & end, int count) + : Out(o, start, end, count < 2 ? ONE_LINE : MULTI_LINE) + {} + Out(const Out &) = delete; + Out(Out &&) = default; + Out & operator=(const Out &) = delete; + Out & operator=(Out &&) = delete; + ~Out() { ostream << end; } + + private: + std::ostream & ostream; + std::string indentation; + std::string end; + LinePolicy policy; + bool writeSinceSep; + template <typename T> friend Out & operator<<(Out & o, T thing); +}; + +template <typename T> Out & operator<<(Out & o, T thing) +{ + if (!o.writeSinceSep && o.policy == Out::MULTI_LINE) { + o.ostream << o.indentation; + } + o.writeSinceSep = true; + o.ostream << thing; + return o; +} + +template <> Out & operator<<<Out::Separator>(Out & o, Out::Separator /* thing */) +{ + o.ostream << (o.policy == Out::ONE_LINE ? " " : "\n"); + o.writeSinceSep = false; + return o; +} + +Out::Out(Out & o, const std::string & start, const std::string & end, LinePolicy policy) + : ostream(o.ostream), indentation(policy == ONE_LINE ? o.indentation : o.indentation + " "), + end(policy == ONE_LINE ? end : o.indentation + end), policy(policy), writeSinceSep(true) +{ + o << start; + *this << Out::sep; +} + +// Stuff needed for evaluation +struct Context +{ + Context(EvalState & state, Bindings & autoArgs, Value optionsRoot, Value configRoot) + : state(state), autoArgs(autoArgs), optionsRoot(optionsRoot), configRoot(configRoot), + underscoreType(state.symbols.create("_type")) + {} + EvalState & state; + Bindings & autoArgs; + Value optionsRoot; + Value configRoot; + Symbol underscoreType; +}; + +Value evaluateValue(Context & ctx, Value & v) +{ + ctx.state.forceValue(v); + if (ctx.autoArgs.empty()) { + return v; + } + Value called{}; + ctx.state.autoCallFunction(ctx.autoArgs, v, called); + return called; +} + +bool isOption(Context & ctx, const Value & v) +{ + if (v.type != tAttrs) { + return false; + } + const auto & atualType = v.attrs->find(ctx.underscoreType); + if (atualType == v.attrs->end()) { + return false; + } + try { + Value evaluatedType = evaluateValue(ctx, *atualType->value); + if (evaluatedType.type != tString) { + return false; + } + return static_cast<std::string>(evaluatedType.string.s) == "option"; + } catch (Error &) { + return false; + } +} + +// Add quotes to a component of a path. +// These are needed for paths like: +// fileSystems."/".fsType +// systemd.units."dbus.service".text +std::string quoteAttribute(const std::string & attribute) +{ + if (isVarName(attribute)) { + return attribute; + } + std::ostringstream buf; + printStringValue(buf, attribute.c_str()); + return buf.str(); +} + +const std::string appendPath(const std::string & prefix, const std::string & suffix) +{ + if (prefix.empty()) { + return quoteAttribute(suffix); + } + return prefix + "." + quoteAttribute(suffix); +} + +bool forbiddenRecursionName(std::string name) { return (!name.empty() && name[0] == '_') || name == "haskellPackages"; } + +void recurse(const std::function<bool(const std::string & path, std::variant<Value, std::exception_ptr>)> & f, + Context & ctx, Value v, const std::string & path) +{ + std::variant<Value, std::exception_ptr> evaluated; + try { + evaluated = evaluateValue(ctx, v); + } catch (Error &) { + evaluated = std::current_exception(); + } + if (!f(path, evaluated)) { + return; + } + if (std::holds_alternative<std::exception_ptr>(evaluated)) { + return; + } + const Value & evaluated_value = std::get<Value>(evaluated); + if (evaluated_value.type != tAttrs) { + return; + } + for (const auto & child : evaluated_value.attrs->lexicographicOrder()) { + if (forbiddenRecursionName(child->name)) { + continue; + } + recurse(f, ctx, *child->value, appendPath(path, child->name)); + } +} + +// Calls f on all the option names +void mapOptions(const std::function<void(const std::string & path)> & f, Context & ctx, Value root) +{ + recurse( + [f, &ctx](const std::string & path, std::variant<Value, std::exception_ptr> v) { + bool isOpt = std::holds_alternative<std::exception_ptr>(v) || isOption(ctx, std::get<Value>(v)); + if (isOpt) { + f(path); + } + return !isOpt; + }, + ctx, root, ""); +} + +// Calls f on all the config values inside one option. +// Simple options have one config value inside, like sound.enable = true. +// Compound options have multiple config values. For example, the option +// "users.users" has about 1000 config values inside it: +// users.users.avahi.createHome = false; +// users.users.avahi.cryptHomeLuks = null; +// users.users.avahi.description = "`avahi-daemon' privilege separation user"; +// ... +// users.users.avahi.openssh.authorizedKeys.keyFiles = [ ]; +// users.users.avahi.openssh.authorizedKeys.keys = [ ]; +// ... +// users.users.avahi.uid = 10; +// users.users.avahi.useDefaultShell = false; +// users.users.cups.createHome = false; +// ... +// users.users.cups.useDefaultShell = false; +// users.users.gdm = ... ... ... +// users.users.messagebus = ... .. ... +// users.users.nixbld1 = ... .. ... +// ... +// users.users.systemd-timesync = ... .. ... +void mapConfigValuesInOption( + const std::function<void(const std::string & path, std::variant<Value, std::exception_ptr> v)> & f, + const std::string & path, Context & ctx) +{ + Value * option; + try { + option = findAlongAttrPath(ctx.state, path, ctx.autoArgs, ctx.configRoot); + } catch (Error &) { + f(path, std::current_exception()); + return; + } + recurse( + [f, ctx](const std::string & path, std::variant<Value, std::exception_ptr> v) { + bool leaf = std::holds_alternative<std::exception_ptr>(v) || std::get<Value>(v).type != tAttrs || + ctx.state.isDerivation(std::get<Value>(v)); + if (!leaf) { + return true; // Keep digging + } + f(path, v); + return false; + }, + ctx, *option, path); +} + +std::string describeError(const Error & e) { return "«error: " + e.msg() + "»"; } + +void describeDerivation(Context & ctx, Out & out, Value v) +{ + // Copy-pasted from nix/src/nix/repl.cc :( + Bindings::iterator i = v.attrs->find(ctx.state.sDrvPath); + PathSet pathset; + try { + Path drvPath = i != v.attrs->end() ? ctx.state.coerceToPath(*i->pos, *i->value, pathset) : "???"; + out << "«derivation " << drvPath << "»"; + } catch (Error & e) { + out << describeError(e); + } +} + +Value parseAndEval(EvalState & state, const std::string & expression, const std::string & path) +{ + Value v{}; + state.eval(state.parseExprFromString(expression, absPath(path)), v); + return v; +} + +void printValue(Context & ctx, Out & out, std::variant<Value, std::exception_ptr> maybeValue, const std::string & path); + +void printList(Context & ctx, Out & out, Value & v) +{ + Out listOut(out, "[", "]", v.listSize()); + for (unsigned int n = 0; n < v.listSize(); ++n) { + printValue(ctx, listOut, *v.listElems()[n], ""); + listOut << Out::sep; + } +} + +void printAttrs(Context & ctx, Out & out, Value & v, const std::string & path) +{ + Out attrsOut(out, "{", "}", v.attrs->size()); + for (const auto & a : v.attrs->lexicographicOrder()) { + std::string name = a->name; + attrsOut << name << " = "; + printValue(ctx, attrsOut, *a->value, appendPath(path, name)); + attrsOut << ";" << Out::sep; + } +} + +void multiLineStringEscape(Out & out, const std::string & s) +{ + int i; + for (i = 1; i < s.size(); i++) { + if (s[i - 1] == '$' && s[i] == '{') { + out << "''${"; + i++; + } else if (s[i - 1] == '\'' && s[i] == '\'') { + out << "'''"; + i++; + } else { + out << s[i - 1]; + } + } + if (i == s.size()) { + out << s[i - 1]; + } +} + +void printMultiLineString(Out & out, const Value & v) +{ + std::string s = v.string.s; + Out strOut(out, "''", "''", Out::MULTI_LINE); + std::string::size_type begin = 0; + while (begin < s.size()) { + std::string::size_type end = s.find('\n', begin); + if (end == std::string::npos) { + multiLineStringEscape(strOut, s.substr(begin, s.size() - begin)); + break; + } + multiLineStringEscape(strOut, s.substr(begin, end - begin)); + strOut << Out::sep; + begin = end + 1; + } +} + +void printValue(Context & ctx, Out & out, std::variant<Value, std::exception_ptr> maybeValue, const std::string & path) +{ + try { + if (auto ex = std::get_if<std::exception_ptr>(&maybeValue)) { + std::rethrow_exception(*ex); + } + Value v = evaluateValue(ctx, std::get<Value>(maybeValue)); + if (ctx.state.isDerivation(v)) { + describeDerivation(ctx, out, v); + } else if (v.isList()) { + printList(ctx, out, v); + } else if (v.type == tAttrs) { + printAttrs(ctx, out, v, path); + } else if (v.type == tString && std::string(v.string.s).find('\n') != std::string::npos) { + printMultiLineString(out, v); + } else { + ctx.state.forceValueDeep(v); + out << v; + } + } catch (ThrownError & e) { + if (e.msg() == "The option `" + path + "' is used but not defined.") { + // 93% of errors are this, and just letting this message through would be + // misleading. These values may or may not actually be "used" in the + // config. The thing throwing the error message assumes that if anything + // ever looks at this value, it is a "use" of this value. But here in + // nixos-option, we are looking at this value only to print it. + // In order to avoid implying that this undefined value is actually + // referenced, eat the underlying error message and emit "«not defined»". + out << "«not defined»"; + } else { + out << describeError(e); + } + } catch (Error & e) { + out << describeError(e); + } +} + +void printConfigValue(Context & ctx, Out & out, const std::string & path, std::variant<Value, std::exception_ptr> v) +{ + out << path << " = "; + printValue(ctx, out, std::move(v), path); + out << ";\n"; +} + +void printAll(Context & ctx, Out & out) +{ + mapOptions( + [&ctx, &out](const std::string & optionPath) { + mapConfigValuesInOption( + [&ctx, &out](const std::string & configPath, std::variant<Value, std::exception_ptr> v) { + printConfigValue(ctx, out, configPath, v); + }, + optionPath, ctx); + }, + ctx, ctx.optionsRoot); +} + +void printAttr(Context & ctx, Out & out, const std::string & path, Value & root) +{ + try { + printValue(ctx, out, *findAlongAttrPath(ctx.state, path, ctx.autoArgs, root), path); + } catch (Error & e) { + out << describeError(e); + } +} + +bool hasExample(Context & ctx, Value & option) +{ + try { + findAlongAttrPath(ctx.state, "example", ctx.autoArgs, option); + return true; + } catch (Error &) { + return false; + } +} + +void printOption(Context & ctx, Out & out, const std::string & path, Value & option) +{ + out << "Value:\n"; + printAttr(ctx, out, path, ctx.configRoot); + + out << "\n\nDefault:\n"; + printAttr(ctx, out, "default", option); + + out << "\n\nType:\n"; + printAttr(ctx, out, "type.description", option); + + if (hasExample(ctx, option)) { + out << "\n\nExample:\n"; + printAttr(ctx, out, "example", option); + } + + out << "\n\nDescription:\n"; + printAttr(ctx, out, "description", option); + + out << "\n\nDeclared by:\n"; + printAttr(ctx, out, "declarations", option); + + out << "\n\nDefined by:\n"; + printAttr(ctx, out, "files", option); + out << "\n"; +} + +void printListing(Out & out, Value & v) +{ + out << "This attribute set contains:\n"; + for (const auto & a : v.attrs->lexicographicOrder()) { + std::string name = a->name; + if (!name.empty() && name[0] != '_') { + out << name << "\n"; + } + } +} + +bool optionTypeIs(Context & ctx, Value & v, const std::string & soughtType) +{ + try { + const auto & typeLookup = v.attrs->find(ctx.state.sType); + if (typeLookup == v.attrs->end()) { + return false; + } + Value type = evaluateValue(ctx, *typeLookup->value); + if (type.type != tAttrs) { + return false; + } + const auto & nameLookup = type.attrs->find(ctx.state.sName); + if (nameLookup == type.attrs->end()) { + return false; + } + Value name = evaluateValue(ctx, *nameLookup->value); + if (name.type != tString) { + return false; + } + return name.string.s == soughtType; + } catch (Error &) { + return false; + } +} + +bool isAggregateOptionType(Context & ctx, Value & v) +{ + return optionTypeIs(ctx, v, "attrsOf") || optionTypeIs(ctx, v, "listOf") || optionTypeIs(ctx, v, "loaOf"); +} + +MakeError(OptionPathError, EvalError); + +Value getSubOptions(Context & ctx, Value & option) +{ + Value getSubOptions = evaluateValue(ctx, *findAlongAttrPath(ctx.state, "type.getSubOptions", ctx.autoArgs, option)); + if (getSubOptions.type != tLambda) { + throw OptionPathError("Option's type.getSubOptions isn't a function"); + } + Value emptyString{}; + nix::mkString(emptyString, ""); + Value v; + ctx.state.callFunction(getSubOptions, emptyString, v, nix::Pos{}); + return v; +} + +// Carefully walk an option path, looking for sub-options when a path walks past +// an option value. +Value findAlongOptionPath(Context & ctx, const std::string & path) +{ + Strings tokens = parseAttrPath(path); + Value v = ctx.optionsRoot; + for (auto i = tokens.begin(); i != tokens.end(); i++) { + const auto & attr = *i; + try { + bool lastAttribute = std::next(i) == tokens.end(); + v = evaluateValue(ctx, v); + if (attr.empty()) { + throw OptionPathError("empty attribute name"); + } + if (isOption(ctx, v) && optionTypeIs(ctx, v, "submodule")) { + v = getSubOptions(ctx, v); + } + if (isOption(ctx, v) && isAggregateOptionType(ctx, v) && !lastAttribute) { + v = getSubOptions(ctx, v); + // Note that we've consumed attr, but didn't actually use it. This is the path component that's looked + // up in the list or attribute set that doesn't name an option -- the "root" in "users.users.root.name". + } else if (v.type != tAttrs) { + throw OptionPathError("Value is %s while a set was expected", showType(v)); + } else { + const auto & next = v.attrs->find(ctx.state.symbols.create(attr)); + if (next == v.attrs->end()) { + throw OptionPathError("Attribute not found", attr, path); + } + v = *next->value; + } + } catch (OptionPathError & e) { + throw OptionPathError("At '%s' in path '%s': %s", attr, path, e.msg()); + } + } + return v; +} + +void printOne(Context & ctx, Out & out, const std::string & path) +{ + try { + Value option = findAlongOptionPath(ctx, path); + option = evaluateValue(ctx, option); + if (isOption(ctx, option)) { + printOption(ctx, out, path, option); + } else { + printListing(out, option); + } + } catch (Error & e) { + std::cerr << "error: " << e.msg() + << "\nAn error occurred while looking for attribute names. Are " + "you sure that '" + << path << "' exists?\n"; + } +} + +int main(int argc, char ** argv) +{ + bool all = false; + std::string path = "."; + std::string optionsExpr = "(import <nixpkgs/nixos> {}).options"; + std::string configExpr = "(import <nixpkgs/nixos> {}).config"; + std::vector<std::string> args; + + struct MyArgs : nix::LegacyArgs, nix::MixEvalArgs + { + using nix::LegacyArgs::LegacyArgs; + }; + + MyArgs myArgs(nix::baseNameOf(argv[0]), [&](Strings::iterator & arg, const Strings::iterator & end) { + if (*arg == "--help") { + nix::showManPage("nixos-option"); + } else if (*arg == "--version") { + nix::printVersion("nixos-option"); + } else if (*arg == "--all") { + all = true; + } else if (*arg == "--path") { + path = nix::getArg(*arg, arg, end); + } else if (*arg == "--options_expr") { + optionsExpr = nix::getArg(*arg, arg, end); + } else if (*arg == "--config_expr") { + configExpr = nix::getArg(*arg, arg, end); + } else if (!arg->empty() && arg->at(0) == '-') { + return false; + } else { + args.push_back(*arg); + } + return true; + }); + + myArgs.parseCmdline(nix::argvToStrings(argc, argv)); + + nix::initPlugins(); + nix::initGC(); + nix::settings.readOnlyMode = true; + auto store = nix::openStore(); + auto state = std::make_unique<EvalState>(myArgs.searchPath, store); + + Value optionsRoot = parseAndEval(*state, optionsExpr, path); + Value configRoot = parseAndEval(*state, configExpr, path); + + Context ctx{*state, *myArgs.getAutoArgs(*state), optionsRoot, configRoot}; + Out out(std::cout); + + if (all) { + if (!args.empty()) { + throw UsageError("--all cannot be used with arguments"); + } + printAll(ctx, out); + } else { + if (args.empty()) { + printOne(ctx, out, ""); + } + for (const auto & arg : args) { + printOne(ctx, out, arg); + } + } + + ctx.state.printStats(); + + return 0; +} diff --git a/nixos/modules/installer/tools/tools.nix b/nixos/modules/installer/tools/tools.nix index 052e7fdd4fc..e4db39b5c81 100644 --- a/nixos/modules/installer/tools/tools.nix +++ b/nixos/modules/installer/tools/tools.nix @@ -41,10 +41,7 @@ let inherit (config.system.nixos-generate-config) configuration; }; - nixos-option = makeProg { - name = "nixos-option"; - src = ./nixos-option.sh; - }; + nixos-option = pkgs.callPackage ./nixos-option { }; nixos-version = makeProg { name = "nixos-version"; |