git.delta.rocks / fleet / refs/commits / 210037fd620b

1use std::borrow::Cow;2use std::cell::RefCell;3use std::collections::HashMap;4use std::ffi::{CStr, CString, c_char, c_int, c_uint, c_void};5use std::ptr::{null, null_mut};6use std::sync::{Arc, LazyLock, OnceLock};7use std::{array, fmt, slice};89use anyhow::{Context, anyhow, bail};10use camino::{Utf8Path, Utf8PathBuf};11use itertools::Itertools;12use serde::Serialize;13use serde::de::DeserializeOwned;14use std::mem::transmute;1516pub use anyhow::Result;17use tracing::{Span, instrument, warn};1819use self::logging::{ErrorInfoBuilder, nix_logging_cxx};20use self::nix_cxx::set_fetcher_setting;21use self::nix_raw::{22	BindingsBuilder as c_bindings_builder, EvalState as c_eval_state, GC_SUCCESS,23	GC_allow_register_threads, GC_get_stack_base, GC_register_my_thread, GC_stack_base,24	GC_thread_is_registered, GC_unregister_my_thread, ListBuilder as c_list_builder, PrimOp,25	PrimOpFun, Store as c_store, StorePath as c_store_path, alloc_primop, alloc_value,26	bindings_builder_free, bindings_builder_insert, c_context, c_context_create, c_context_free,27	clear_err, copy_value, err_NIX_ERR_KEY, err_NIX_ERR_NIX_ERROR, err_NIX_ERR_OVERFLOW,28	err_NIX_ERR_UNKNOWN, err_NIX_OK, err_code, err_info_msg, err_msg, eval_state_build,29	eval_state_builder_load, eval_state_builder_new, eval_state_builder_set_eval_setting,30	expr_eval_from_string, fetchers_settings, fetchers_settings_free, fetchers_settings_new,31	flake_lock, flake_lock_flags, flake_lock_flags_free, flake_lock_flags_new, flake_reference,32	flake_reference_and_fragment_from_string, flake_reference_parse_flags,33	flake_reference_parse_flags_free, flake_reference_parse_flags_new,34	flake_reference_parse_flags_set_base_directory, flake_settings, flake_settings_free,35	flake_settings_new, gc_now as gc_now_raw, get_attr_byname, get_attr_name_byidx, get_attrs_size,36	get_list_byidx, get_list_size, get_string, get_type, has_attr_byname, init_bool, init_int,37	init_primop, init_string, libexpr_init, libstore_init, libutil_init, list_builder_free,38	list_builder_insert, locked_flake, locked_flake_free, locked_flake_get_output_attrs,39	make_attrs, make_bindings_builder, make_list, make_list_builder, realised_string,40	realised_string_free, realised_string_get_buffer_size, realised_string_get_buffer_start,41	realised_string_get_store_path, realised_string_get_store_path_count, register_primop,42	set_err_msg, setting_set, state_free, store_copy_closure, store_free, store_open,43	store_parse_path, store_path_free, store_path_name, string_realise, value, value_call,44	value_decref, value_force, value_incref,45};4647// Contains macros helpers48pub mod drv;49pub mod logging;50#[doc(hidden)]51pub mod macros;52pub mod scheduler;5354#[doc(hidden)]55pub mod __macro_support {56	pub use std::collections::hash_map::HashMap;5758	pub use anyhow::Context;59	pub use tokio::task::block_in_place;60}61pub mod util;6263#[allow(64	non_upper_case_globals,65	non_camel_case_types,66	non_snake_case,67	dead_code68)]69mod nix_raw {70	include!(concat!(env!("OUT_DIR"), "/bindings.rs"));71}72#[cxx::bridge]73pub mod nix_cxx {74	struct AddFileToStoreResult {75		error: String,76		store_path: String,77		hash: String,78	}79	struct CxxProfileGeneration {80		id: u64,81		store_path: String,82		creation_time_unix: i64,83		current: bool,84	}85	struct CxxListGenerationsResult {86		error: String,87		generations: Vec<CxxProfileGeneration>,88	}89	struct CxxBuildResult {90		error: String,91		outputs: Vec<String>,92	}93	unsafe extern "C++" {94		type nix_fetchers_settings;95		type Store;96		include!("nix-eval/src/lib.hh");9798		#[allow(clippy::missing_safety_doc)]99		unsafe fn set_fetcher_setting(100			settings: *mut nix_fetchers_settings,101			setting: *const c_char,102			value: *const c_char,103		);104105		#[allow(clippy::missing_safety_doc)]106		unsafe fn switch_profile(store: *mut Store, profile: &str, store_path: &str) -> String;107108		#[allow(clippy::missing_safety_doc)]109		unsafe fn sign_closure(store: *mut Store, store_path: &str, key_file: &str) -> String;110111		#[allow(clippy::missing_safety_doc)]112		unsafe fn add_file_to_store(113			store: *mut Store,114			name: &str,115			path: &str,116		) -> AddFileToStoreResult;117118		fn list_generations(profile_path: &str) -> CxxListGenerationsResult;119120		#[allow(clippy::missing_safety_doc)]121		unsafe fn build_drv_outputs(122			store: *mut Store,123			drv_path: &str,124			output_names_joined: &str,125		) -> CxxBuildResult;126127		#[allow(clippy::missing_safety_doc)]128		unsafe fn substitute_paths(store: *mut Store, paths_joined: &str) -> CxxBuildResult;129130		#[allow(clippy::missing_safety_doc)]131		unsafe fn is_valid_path(store: *mut Store, path: &str) -> bool;132	}133}134135#[derive(Debug, PartialEq, Eq)]136pub enum NixType {137	Thunk,138	Int,139	Float,140	Bool,141	String,142	Path,143	Null,144	Attrs,145	List,146	Function,147	External,148}149impl NixType {150	fn from_int(c: c_uint) -> Self {151		match c {152			0 => Self::Thunk,153			1 => Self::Int,154			2 => Self::Float,155			3 => Self::Bool,156			4 => Self::String,157			5 => Self::Path,158			6 => Self::Null,159			7 => Self::Attrs,160			8 => Self::List,161			9 => Self::Function,162			10 => Self::External,163			_ => unreachable!("unknown nix type: {c}"),164		}165	}166}167168enum FunctorKind {169	Function,170	Functor,171}172173#[derive(Debug)]174#[repr(i32)]175pub enum NixErrorKind {176	Unknown = err_NIX_ERR_UNKNOWN,177	Overflow = err_NIX_ERR_OVERFLOW,178	Key = err_NIX_ERR_KEY,179	Generic = err_NIX_ERR_NIX_ERROR,180}181impl NixErrorKind {182	fn from_int(v: c_int) -> Option<Self> {183		Some(match v {184			0 => return None,185			nix_raw::err_NIX_ERR_UNKNOWN => Self::Unknown,186			nix_raw::err_NIX_ERR_OVERFLOW => Self::Overflow,187			nix_raw::err_NIX_ERR_KEY => Self::Key,188			nix_raw::err_NIX_ERR_NIX_ERROR => Self::Generic,189			_ => {190				debug_assert!(false, "unexpected nix error kind: {v}");191				Self::Unknown192			}193		})194	}195}196197pub fn gc_now() {198	unsafe { gc_now_raw() };199}200201pub fn gc_register_my_thread() {202	assert_eq!(unsafe { GC_thread_is_registered() }, 0);203204	let mut sb = GC_stack_base {205		mem_base: null_mut(),206	};207	let r = unsafe { GC_get_stack_base(&mut sb) };208	if r as u32 != GC_SUCCESS {209		panic!("failed to get thread stack base");210	}211	unsafe { GC_register_my_thread(&sb) };212}213pub fn gc_unregister_my_thread() {214	assert_eq!(unsafe { GC_thread_is_registered() }, 1);215216	unsafe { GC_unregister_my_thread() };217}218219pub struct ThreadRegisterGuard {}220impl ThreadRegisterGuard {221	#[allow(clippy::new_without_default)]222	pub fn new() -> Self {223		gc_register_my_thread();224		Self {}225	}226}227impl Drop for ThreadRegisterGuard {228	fn drop(&mut self) {229		gc_unregister_my_thread();230	}231}232233#[repr(transparent)]234pub struct NixContext(*mut c_context);235impl NixContext {236	pub fn set_err_raw(&mut self, err: NixErrorKind, msg: &CStr) {237		unsafe { set_err_msg(self.0, err as c_int, msg.as_ptr()) };238	}239	pub fn set_err(&mut self, err: anyhow::Error) {240		let fmt = format!("{err:?}").replace("\0", "\\0");241		self.set_err_raw(242			NixErrorKind::Generic,243			&CString::new(fmt).expect("NUL bytes were just replaced"),244		);245	}246	pub fn new() -> Self {247		let ctx = unsafe { c_context_create() };248		Self(ctx)249	}250	fn error_kind(&self) -> Option<NixErrorKind> {251		let code = unsafe { err_code(self.0) };252		NixErrorKind::from_int(code)253	}254	fn error<'t>(&self) -> Option<(Cow<'t, str>, Option<Box<ErrorInfoBuilder>>)> {255		if let NixErrorKind::Generic = self.error_kind()? {256			let ei = unsafe { logging::nix_logging_cxx::extract_error_info(self.0) };257			let mut err_out = String::new();258			unsafe {259				err_info_msg(260					null_mut(),261					self.0,262					Some(copy_nix_str),263					(&raw mut err_out).cast(),264				)265			};266			return Some((Cow::Owned(err_out), Some(ei)));267		};268269		// TODO: Can throw error (resulting in panic) if unable to retrieve error. Should be able to resolve by passing context as a first argument,270		// but it looks ugly271		let str = unsafe { err_msg(null_mut(), self.0, null_mut()) };272		Some((unsafe { CStr::from_ptr(str) }.to_string_lossy(), None))273	}274	fn clean_err(&mut self) {275		unsafe {276			clear_err(self.0);277		}278	}279280	fn bail_if_error(&self) -> Result<()> {281		if let Some((err, stack)) = self.error() {282			let mut e = Err(anyhow!("{err}"));283			if let Some(stack) = stack {284				for ele in stack.stack_frames {285					e = e.with_context(|| {286						if ele.pos.is_empty() {287							ele.msg288						} else {289							format!("{} at {}", ele.msg, ele.pos)290						}291					})292				}293			}294			return e.context("<nix frames>");295		};296		Ok(())297	}298299	fn run_in_context<T>(&mut self, f: impl FnOnce(*mut c_context) -> T) -> Result<T> {300		self.clean_err();301		let o = f(self.0);302		self.bail_if_error()?;303		self.clean_err();304		Ok(o)305	}306}307308impl Default for NixContext {309	fn default() -> Self {310		Self::new()311	}312}313impl Drop for NixContext {314	fn drop(&mut self) {315		unsafe {316			c_context_free(self.0);317		}318	}319}320struct GlobalState {321	// Store should be valid as long as EvalState is valid322	#[allow(dead_code)]323	store: Arc<Store>,324	state: EvalState,325}326impl GlobalState {327	fn new() -> Result<Self> {328		let mut ctx = NixContext::new();329		let store = Arc::new(330			ctx.run_in_context(|c| unsafe { store_open(c, c"auto".as_ptr(), null_mut()) })331				.map(Store)?,332		);333334		let builder = ctx.run_in_context(|c| unsafe { eval_state_builder_new(c, store.0) })?;335		ctx.run_in_context(|c| unsafe { eval_state_builder_load(c, builder) })?;336		ctx.run_in_context(|c| unsafe {337			eval_state_builder_set_eval_setting(338				c,339				builder,340				c"lazy-trees".as_ptr(),341				c"true".as_ptr(),342			)343		})?;344		ctx.run_in_context(|c| unsafe {345			eval_state_builder_set_eval_setting(346				c,347				builder,348				c"lazy-locks".as_ptr(),349				c"true".as_ptr(),350			)351		})?;352		let state = ctx353			.run_in_context(|c| unsafe { eval_state_build(c, builder) })354			.map(EvalState)?;355356		Ok(Self { store, state })357	}358}359360struct ThreadState {361	ctx: NixContext,362}363impl ThreadState {364	fn new() -> Result<Self> {365		let ctx = NixContext::new();366367		Ok(Self { ctx })368	}369}370371static GLOBAL_STATE: LazyLock<GlobalState> =372	LazyLock::new(|| GlobalState::new().expect("global state init shouldn't fail"));373374thread_local! {375	static THREAD_STATE: RefCell<ThreadState> = RefCell::new(ThreadState::new().expect("thread state init shouldn't fail"));376}377pub(crate) fn with_default_context<T>(378	f: impl FnOnce(*mut c_context, *mut c_eval_state) -> T,379) -> Result<T> {380	let global = &GLOBAL_STATE.state;381	let (ctx, state) = THREAD_STATE.with_borrow_mut(|w| (w.ctx.0, global.0));382	let mut ctx = NixContext(ctx);383	let v = ctx.run_in_context(|c| f(c, state));384	// It is reused for thread385	std::mem::forget(ctx);386	v387}388389pub fn set_setting(s: &CStr, v: &CStr) -> Result<()> {390	with_default_context(|c, _| unsafe { setting_set(c, s.as_ptr(), v.as_ptr()) }).map(|_| ())391}392393#[derive(Debug)]394pub struct AddedFile {395	pub store_path: Utf8PathBuf,396	pub hash: String,397}398399#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]400pub struct ProfileGeneration {401	pub id: u64,402	pub store_path: Utf8PathBuf,403	pub creation_time_unix: i64,404	pub current: bool,405}406407#[instrument]408pub fn list_generations(profile_path: &str) -> Result<Vec<ProfileGeneration>> {409	let res = nix_cxx::list_generations(profile_path);410	if !res.error.is_empty() {411		bail!(412			"failed to list generations at {profile_path}: {}",413			res.error414		);415	}416	Ok(res417		.generations418		.into_iter()419		.map(|g| ProfileGeneration {420			id: g.id,421			store_path: Utf8PathBuf::from(g.store_path),422			creation_time_unix: g.creation_time_unix,423			current: g.current,424		})425		.collect())426}427428pub struct FetchSettings(*mut fetchers_settings);429impl FetchSettings {430	pub fn new() -> Self {431		Self::try_new().expect("allocation should not fail")432	}433	fn try_new() -> Result<Self> {434		with_default_context(|c, _| unsafe { fetchers_settings_new(c) }).map(Self)435	}436	pub fn set(&mut self, setting: &CStr, value: &CStr) {437		unsafe {438			set_fetcher_setting(self.0.cast(), setting.as_ptr(), value.as_ptr());439		};440	}441}442unsafe impl Send for FetchSettings {}443unsafe impl Sync for FetchSettings {}444445impl Default for FetchSettings {446	fn default() -> Self {447		Self::new()448	}449}450451impl Drop for FetchSettings {452	fn drop(&mut self) {453		unsafe { fetchers_settings_free(self.0) };454	}455}456pub struct FlakeSettings(*mut flake_settings);457impl FlakeSettings {458	pub fn new() -> Result<Self> {459		with_default_context(|c, _| unsafe { flake_settings_new(c) }).map(Self)460	}461}462unsafe impl Send for FlakeSettings {}463unsafe impl Sync for FlakeSettings {}464impl Drop for FlakeSettings {465	fn drop(&mut self) {466		unsafe {467			flake_settings_free(self.0);468		}469	}470}471472pub struct FlakeReferenceParseFlags(*mut flake_reference_parse_flags);473impl FlakeReferenceParseFlags {474	pub fn new(settings: &FlakeSettings) -> Result<Self> {475		with_default_context(|c, _| unsafe { flake_reference_parse_flags_new(c, settings.0) })476			.map(Self)477	}478	pub fn set_base_dir(&mut self, dir: &str) -> Result<()> {479		with_default_context(|c, _| {480			unsafe {481				flake_reference_parse_flags_set_base_directory(482					c,483					self.0,484					dir.as_ptr().cast(),485					dir.len(),486				)487			};488		})489	}490}491impl Drop for FlakeReferenceParseFlags {492	fn drop(&mut self) {493		unsafe {494			flake_reference_parse_flags_free(self.0);495		}496	}497}498pub struct FlakeLockFlags(*mut flake_lock_flags);499impl FlakeLockFlags {500	pub fn new(settings: &FlakeSettings) -> Result<Self> {501		let o = with_default_context(|c, _| unsafe { flake_lock_flags_new(c, settings.0) })502			.map(Self)?;503		// with_default_context(|c, _| unsafe { flake_lock_flags_set_mode_virtual(c, o.0) })?;504505		Ok(o)506	}507}508impl Drop for FlakeLockFlags {509	fn drop(&mut self) {510		unsafe {511			flake_lock_flags_free(self.0);512		}513	}514}515516pub(crate) unsafe extern "C" fn copy_nix_str(517	start: *const c_char,518	n: c_uint,519	user_data: *mut c_void,520) {521	let s = unsafe { slice::from_raw_parts(start.cast::<u8>(), n as usize) };522	let s = std::str::from_utf8(s).expect("c string has invalid utf-8");523	unsafe { *user_data.cast::<String>() = s.to_owned() };524}525526pub struct Store(*mut c_store);527unsafe impl Send for Store {}528unsafe impl Sync for Store {}529530pub fn eval_store() -> Arc<Store> {531	GLOBAL_STATE.store.clone()532}533534impl Store {535	pub fn open(uri: &str) -> Result<Self> {536		let uri = CString::new(uri)?;537		let ptr = with_default_context(|c, _| unsafe { store_open(c, uri.as_ptr(), null_mut()) })?;538		if ptr.is_null() {539			bail!("failed to open store");540		}541		Ok(Store(ptr))542	}543544	pub fn parse_path(&self, path: &Utf8Path) -> Result<StorePath> {545		let path = CString::new(path.as_str()).expect("valid cstr");546		with_default_context(|c, _| {547			StorePath(unsafe { store_parse_path(c, self.0, path.as_ptr()) })548		})549	}550551	#[instrument(skip(self))]552	pub fn sign_closure(&self, path: &Utf8Path, key_file: &Utf8Path) -> Result<()> {553		let err = with_default_context(|_, _| unsafe {554			nix_cxx::sign_closure(self.as_ptr().cast(), path.as_str(), key_file.as_str())555		})?556		.to_string();557558		if err.is_empty() {559			Ok(())560		} else {561			bail!("failed to sign {path}: {err}");562		}563	}564565	#[instrument(skip(self, dst))]566	pub fn copy_to(&self, dst: &Store, path: &Utf8Path) -> Result<()> {567		let sp = self568			.parse_path(&path)569			.context("failed to parse store path")?;570		let rc = with_default_context(|c, _| unsafe {571			store_copy_closure(c, self.as_ptr(), dst.0, sp.as_ptr())572		})?;573		if rc != err_NIX_OK {574			bail!("store_copy_closure failed (code {rc})");575		}576		Ok(())577	}578579	/// Would only work with local store.580	#[instrument(skip(self))]581	pub fn switch_profile(&self, profile: &str, path: &Utf8Path) -> Result<()> {582		let msg = unsafe { nix_cxx::switch_profile(self.as_ptr().cast(), profile, path.as_str()) };583		if msg.is_empty() {584			Ok(())585		} else {586			bail!("failed to switch profile {profile}: {msg}");587		}588	}589590	#[instrument(skip(self))]591	pub fn add_file(&self, name: &str, path: &Utf8Path) -> Result<AddedFile> {592		let msg = unsafe { nix_cxx::add_file_to_store(self.as_ptr().cast(), name, path.as_str()) };593		if !msg.error.is_empty() {594			bail!("failed to add {path} to store: {}", msg.error)595		}596		Ok(AddedFile {597			store_path: Utf8PathBuf::from(msg.store_path),598			hash: msg.hash,599		})600	}601602	#[instrument(skip(self))]603	pub fn substitute_paths(&self, paths: &[Utf8PathBuf]) -> Result<Vec<Utf8PathBuf>> {604		let joined = paths.into_iter().join("\n");605		let res = unsafe { nix_cxx::substitute_paths(self.as_ptr().cast(), &joined) };606		if !res.error.is_empty() {607			warn!("substitute_paths reported: {}", res.error);608		}609		Ok(res.outputs.into_iter().map(Utf8PathBuf::from).collect())610	}611612	#[instrument(skip(self))]613	pub fn is_valid_path(&self, path: &Utf8Path) -> bool {614		unsafe { nix_cxx::is_valid_path(self.as_ptr().cast(), path.as_str()) }615	}616617	#[instrument(skip(self))]618	pub fn build_drv_outputs(619		&self,620		drv_path: &Utf8Path,621		output_names: &[String],622	) -> Result<Vec<String>> {623		let joined = output_names.join("\n");624		let res =625			unsafe { nix_cxx::build_drv_outputs(self.as_ptr().cast(), drv_path.as_str(), &joined) };626		if !res.error.is_empty() {627			bail!("build of {drv_path} failed: {}", res.error);628		}629		Ok(res.outputs)630	}631632	#[instrument(skip(self))]633	pub fn store_dir(&self) -> Result<Utf8PathBuf> {634		let mut out = String::new();635		with_default_context(|c, es| unsafe {636			nix_raw::store_get_storedir(c, self.as_ptr(), Some(copy_nix_str), (&raw mut out).cast())637		})?;638		let p = Utf8PathBuf::from(out);639		assert!(p.is_absolute());640		Ok(p)641	}642643	fn as_ptr(&self) -> *mut c_store {644		self.0645	}646}647impl Drop for Store {648	fn drop(&mut self) {649		unsafe { store_free(self.0) }650	}651}652653#[repr(transparent)]654pub struct EvalState(*mut c_eval_state);655unsafe impl Send for EvalState {}656unsafe impl Sync for EvalState {}657658impl Drop for EvalState {659	fn drop(&mut self) {660		unsafe {661			state_free(self.0);662		}663	}664}665666pub struct FlakeReference(*mut flake_reference);667impl FlakeReference {668	#[instrument(name = "new-flake-reference", skip(flake, parse, fetch))]669	pub fn new(670		s: &str,671		flake: &FlakeSettings,672		parse: &FlakeReferenceParseFlags,673		fetch: &FetchSettings,674	) -> Result<(Self, String)> {675		let mut out = null_mut();676		let mut fragment = String::new();677		// let fetch_settings = fetcher_settings;678		with_default_context(|c, _| unsafe {679			flake_reference_and_fragment_from_string(680				c,681				fetch.0,682				flake.0,683				parse.0,684				s.as_ptr().cast(),685				s.len(),686				&mut out,687				Some(copy_nix_str),688				(&raw mut fragment).cast(),689			)690		})?;691		assert!(!out.is_null());692693		Ok((Self(out), fragment))694	}695	#[instrument(name = "lock-flake", skip(self, fetch, flake, lock))]696	pub fn lock(697		&mut self,698		fetch: &FetchSettings,699		flake: &FlakeSettings,700		lock: &FlakeLockFlags,701	) -> Result<LockedFlake> {702		with_default_context(|c, es| unsafe { flake_lock(c, fetch.0, flake.0, es, lock.0, self.0) })703			.map(LockedFlake)704	}705}706unsafe impl Send for FlakeReference {}707unsafe impl Sync for FlakeReference {}708709pub struct LockedFlake(*mut locked_flake);710impl LockedFlake {711	pub fn get_attrs(&self, settings: &mut FlakeSettings) -> Result<Value> {712		with_default_context(|c, es| unsafe {713			locked_flake_get_output_attrs(c, settings.0, es, self.0)714		})715		.map(Value)716	}717}718unsafe impl Send for LockedFlake {}719unsafe impl Sync for LockedFlake {}720impl Drop for LockedFlake {721	fn drop(&mut self) {722		unsafe {723			locked_flake_free(self.0);724		};725	}726}727728type FieldName = [u8; 64];729fn init_field_name(v: &str) -> FieldName {730	let mut f = [0; 64];731	assert!(v.len() < 64, "max field name is 63 chars");732	assert!(733		v.bytes().all(|v| v != 0),734		"nul bytes are unsupported in field name"735	);736	f[0..v.len()].copy_from_slice(v.as_bytes());737	f738}739740pub struct RealisedString(*mut realised_string);741impl fmt::Debug for RealisedString {742	fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {743		self.as_str().fmt(f)744	}745}746747impl RealisedString {748	pub fn as_str(&self) -> &str {749		let len = unsafe { realised_string_get_buffer_size(self.0) };750		let data: *const u8 = unsafe { realised_string_get_buffer_start(self.0) }.cast();751		let data = unsafe { slice::from_raw_parts(data, len) };752		std::str::from_utf8(data).expect("non-utf8 strings not supported")753	}754	pub fn path_count(&self) -> usize {755		unsafe { realised_string_get_store_path_count(self.0) }756	}757	pub fn path(&self, i: usize) -> String {758		assert!(i < self.path_count());759		let path = unsafe { realised_string_get_store_path(self.0, i) };760		let mut err_out = String::new();761		unsafe { store_path_name(path, Some(copy_nix_str), (&raw mut err_out).cast()) };762		err_out763	}764}765766unsafe impl Send for RealisedString {}767impl Drop for RealisedString {768	fn drop(&mut self) {769		unsafe { realised_string_free(self.0) }770	}771}772773#[repr(transparent)]774pub struct Value(*mut value);775776unsafe impl Send for Value {}777unsafe impl Sync for Value {}778779pub trait AsFieldName {780	fn as_field_name<T>(&self, v: impl FnOnce(FieldName) -> Result<T>) -> Result<T>;781	fn to_field_name(&self) -> Result<String>;782}783impl AsFieldName for Value {784	fn as_field_name<T>(&self, v: impl FnOnce(FieldName) -> Result<T>) -> Result<T> {785		let f = self.to_string()?;786		v(init_field_name(&f))787	}788	fn to_field_name(&self) -> Result<String> {789		self.to_string()790	}791}792impl<E> AsFieldName for E793where794	E: AsRef<str>,795{796	fn as_field_name<T>(&self, v: impl FnOnce(FieldName) -> Result<T>) -> Result<T> {797		let f = self.as_ref();798		v(init_field_name(f))799	}800	fn to_field_name(&self) -> Result<String> {801		Ok(self.as_ref().to_owned())802	}803}804805struct AttrsBuilder(*mut c_bindings_builder);806impl AttrsBuilder {807	fn new(capacity: usize) -> Self {808		with_default_context(|c, es| unsafe { make_bindings_builder(c, es, capacity) })809			.map(Self)810			.expect("alloc should not fail")811	}812	fn insert(&mut self, k: &impl AsFieldName, v: Value) {813		k.as_field_name(|name| {814			with_default_context(|c, _| unsafe {815				bindings_builder_insert(c, self.0, name.as_ptr().cast(), v.0);816				// bindings_builder_insert doesn't do incref817			})818		})819		.expect("builder insert shouldn't fail");820	}821}822impl Drop for AttrsBuilder {823	fn drop(&mut self) {824		unsafe { bindings_builder_free(self.0) };825	}826}827828struct ListBuilder(*mut c_list_builder, c_uint);829impl ListBuilder {830	fn new(capacity: usize) -> Self {831		with_default_context(|c, es| unsafe { make_list_builder(c, es, capacity) })832			.map(|l| Self(l, 0))833			.expect("alloc should not fail")834	}835}836impl ListBuilder {837	fn push(&mut self, v: Value) {838		with_default_context(|c, _| unsafe {839			list_builder_insert(840				c,841				self.0,842				{843					let v = self.1;844					self.1 += 1;845					v846				},847				v.0,848			)849		})850		.expect("list insert shouldn't fail");851	}852}853impl Drop for ListBuilder {854	fn drop(&mut self) {855		unsafe { list_builder_free(self.0) };856	}857}858859impl Value {860	pub fn new_primop(v: NativeFn) -> Self {861		let out = Self::new_uninit();862		with_default_context(|c, _| unsafe { init_primop(c, out.0, v.0) })863			.expect("primop initialization should not fail");864		out865	}866	pub fn new_attrs(v: HashMap<&str, Value>) -> Self {867		let out = Self::new_uninit();868		let mut b = AttrsBuilder::new(v.len());869		for (k, v) in v {870			b.insert(&k, v);871		}872		with_default_context(|c, _| unsafe { make_attrs(c, out.0, b.0) })873			.expect("attrs initialization should not fail");874875		out876	}877	fn new_list<T: Into<Self>>(v: Vec<T>) -> Self {878		let out = Self::new_uninit();879		let mut b = ListBuilder::new(v.len());880		for v in v {881			b.push(v.into());882		}883		with_default_context(|c, _| unsafe { make_list(c, b.0, out.0) })884			.expect("list initialization should not fail");885886		out887	}888	fn new_uninit() -> Self {889		let out = with_default_context(|c, es| unsafe { alloc_value(c, es) })890			.expect("value allocation should not fail");891		Self(out)892	}893	pub fn new_str(v: &str) -> Self {894		let s = CString::new(v).expect("string should not contain NULs");895		let out = Self::new_uninit();896		// String is copied, `s` is free to be dropped897		with_default_context(|c, _| unsafe { init_string(c, out.0, s.as_ptr()) })898			.expect("string initialization should not fail");899		out900	}901	pub fn new_int(i: i64) -> Self {902		let out = Self::new_uninit();903		with_default_context(|c, _| unsafe { init_int(c, out.0, i) })904			.expect("int initialization should not fail");905		out906	}907	pub fn new_bool(v: bool) -> Self {908		let out = Self::new_uninit();909		with_default_context(|c, _| unsafe { init_bool(c, out.0, v) })910			.expect("bool initialization should not fail");911		out912	}913	// TODO: As far as I can see, there is no way to get Thunks from nix public C api, so this function is useless914	// fn force(&mut self, st: &mut EvalState) -> Result<()> {915	// 	with_default_context(|c, _| unsafe { value_force(c, st.0, self.0) })?;916	// 	Ok(())917	// }918	pub fn type_of(&self) -> NixType {919		let ty = with_default_context(|c, _| unsafe { get_type(c, self.0) })920			.expect("get_type should not fail");921		NixType::from_int(ty)922	}923	fn builtin_to_string(&self) -> Result<Self> {924		let builtin = Self::eval("builtins.toString")?;925		builtin.call(self.clone())926	}927	fn force(&mut self, s: *mut nix_raw::EvalState) -> Result<()> {928		with_default_context(|c, _| unsafe { value_force(c, s, self.0) })?;929		Ok(())930	}931	pub fn to_string(&self) -> Result<String> {932		let ty = self.type_of();933		if !matches!(ty, NixType::String) {934			bail!("unexpected type: {ty:?}, expected string");935		}936		let mut str_out = String::new();937		with_default_context(|c, _| unsafe {938			get_string(c, self.0, Some(copy_nix_str), (&raw mut str_out).cast())939		})?;940941		Ok(str_out)942	}943	pub fn to_realised_string(&self) -> Result<RealisedString> {944		with_default_context(|c, es| unsafe { string_realise(c, es, self.0, false) })945			.map(RealisedString)946947		// let store_paths = unsafe { nix_raw::realised_string_get_store_path_count(str) };948		// for i in 0..store_paths {949		// 	let store_path = unsafe { nix_raw::realised_string_get_store_path(str, i) };950		// 	nix_raw::store_path_name(store_path, callback, user_data);951		// }952		// dbg!(store_paths);953		// todo!();954	}955956	pub fn has_field(&self, field: &str) -> Result<bool> {957		if !matches!(self.type_of(), NixType::Attrs) {958			bail!("invalid type: expected attrs");959		}960961		let f = init_field_name(field);962		with_default_context(|c, es| unsafe { has_attr_byname(c, self.0, es, f.as_ptr().cast()) })963	}964	// pub fn derivation_path(&self) {965	// 	nix_raw::real966	// }967	pub fn list_fields(&self) -> Result<Vec<String>> {968		if !matches!(self.type_of(), NixType::Attrs) {969			bail!("invalid type: expected attrs");970		}971972		let len = with_default_context(|c, _| unsafe { get_attrs_size(c, self.0) })?;973		let mut out = Vec::with_capacity(len as usize);974975		for i in 0..len {976			let name =977				with_default_context(|c, es| unsafe { get_attr_name_byidx(c, self.0, es, i) })?;978			let c = unsafe { CStr::from_ptr(name) };979			out.push(c.to_str().expect("nix field names are utf-8").to_owned());980		}981		Ok(out)982	}983	pub fn get_elem(&self, v: usize) -> Result<Self> {984		if !matches!(self.type_of(), NixType::List) {985			bail!("invalid type: expected list");986		}987		let len = with_default_context(|c, _| unsafe { get_list_size(c, self.0) })? as usize;988		if v >= len {989			bail!("oob list get: {v} >= {len}");990		}991992		with_default_context(|c, es| unsafe { get_list_byidx(c, self.0, es, v as u32) }).map(Self)993	}994	pub fn attrs_update(self, other: Value /*, ignore_errors: bool*/) -> Result<Self> {995		let attrs_update_fn = Self::eval("a: b: a // b")?;996997		attrs_update_fn998			.call(self)?999			.call(other)1000			.context("attrs update")1001	}1002	pub fn get_field(&self, name: impl AsFieldName) -> Result<Self> {1003		if !matches!(self.type_of(), NixType::Attrs) {1004			bail!("invalid type: expected attrs");1005		}10061007		name.as_field_name(|name| {1008			with_default_context(|c, es| unsafe {1009				get_attr_byname(c, self.0, es, name.as_ptr().cast())1010			})1011			.map(Self)1012		})1013		.with_context(|| format!("getting field {:?}", name.to_field_name()))1014	}1015	pub fn call(&self, v: Value) -> Result<Self> {1016		let kind = self1017			.functor_kind()1018			.ok_or_else(|| anyhow!("can only call function or functor"))?;10191020		let function = match kind {1021			FunctorKind::Function => self.clone(),1022			FunctorKind::Functor => {1023				let f = self1024					.get_field("__functor")1025					.context("getting functor value")?;1026				assert_eq!(1027					f.type_of(),1028					NixType::Function,1029					"invalid functor encountered"1030				);1031				f1032			}1033		};10341035		let out = Value::new_uninit();1036		with_default_context(|c, es| unsafe { value_call(c, es, function.0, v.0, out.0) })?;10371038		Ok(out)1039	}1040	pub fn eval(v: &str) -> Result<Self> {1041		let s = CString::new(v).expect("expression shouldn't have internal NULs");1042		let out = Self::new_uninit();1043		with_default_context(|c, es| unsafe {1044			expr_eval_from_string(c, es, s.as_ptr(), c"/root".as_ptr(), out.0)1045		})?;1046		Ok(out)1047	}1048	#[instrument(name = "build", skip(self), fields(output))]1049	pub fn build(&self, output: &str) -> Result<Utf8PathBuf> {1050		if !self.is_derivation() {1051			bail!("expected derivation to build")1052		}1053		let output_name = self1054			.get_field("outputName")1055			.context("getting output name field")?1056			.to_string()?;1057		let v = if output_name != output {1058			let out = self.get_field(output).context("getting target output")?;1059			if !out.is_derivation() {1060				bail!("unknown output: {output}");1061			}1062			out1063		} else {1064			self.clone()1065		};10661067		let drv_path = Utf8PathBuf::from(1068			v.get_field("drvPath")1069				.context("getting drvPath")?1070				.to_string()?,1071		);1072		let graph = Arc::new(drv::DrvGraph::resolve(&eval_store(), &drv_path)?);1073		let _guard = logging::register_build_graph(&Span::current(), &graph);10741075		scheduler::build_graph_sync(graph.clone(), vec![output.to_owned()])?;10761077		let s = v.builtin_to_string()?;1078		let rs = s.to_realised_string()?;1079		let out_path = rs.as_str().to_owned();1080		Ok(Utf8PathBuf::from(out_path))1081	}1082	pub fn as_json<T: DeserializeOwned>(&self) -> Result<T> {1083		let to_json = Self::eval("builtins.toJSON")?;1084		let s = to_json.call(self.clone())?.to_string()?;1085		Ok(serde_json::from_str(&s)?)1086	}1087	pub fn serialized<T: Serialize>(v: &T) -> Result<Self> {1088		Self::eval(&nixlike::serialize(v)?)1089	}10901091	// Convert to string/evaluate derivations/etc1092	// fn to_string_weak(&self) -> Result<String> {1093	// 	// TODO: For now, it works exactly like to_string, see the comment for fn force()1094	// 	self.to_string()1095	// }10961097	fn is_derivation(&self) -> bool {1098		if !matches!(self.type_of(), NixType::Attrs) {1099			return false;1100		}1101		let Some(ty) = self.get_field("type").ok() else {1102			return false;1103		};1104		matches!(ty.to_string().as_deref(), Ok("derivation"))1105	}1106	fn functor_kind(&self) -> Option<FunctorKind> {1107		match self.type_of() {1108			NixType::Attrs => self1109				.has_field("__functor")1110				.expect("has_field shouldn't fail for attrs")1111				.then_some(FunctorKind::Functor),1112			NixType::Function => Some(FunctorKind::Function),1113			_ => None,1114		}1115	}1116	pub fn is_function(&self) -> bool {1117		self.functor_kind().is_some()1118	}1119	pub fn is_null(&self) -> bool {1120		matches!(self.type_of(), NixType::Null)1121	}1122	pub fn is_string(&self) -> bool {1123		matches!(self.type_of(), NixType::String)1124	}1125	pub fn is_attrs(&self) -> bool {1126		matches!(self.type_of(), NixType::Attrs)1127	}1128}11291130impl From<String> for Value {1131	fn from(value: String) -> Self {1132		Value::new_str(&value)1133	}1134}1135impl From<bool> for Value {1136	fn from(value: bool) -> Self {1137		Value::new_bool(value)1138	}1139}1140impl From<&str> for Value {1141	fn from(value: &str) -> Self {1142		Value::new_str(value)1143	}1144}1145impl<T> From<Vec<T>> for Value1146where1147	T: Into<Value>,1148{1149	fn from(value: Vec<T>) -> Self {1150		Value::new_list(value)1151	}1152}11531154impl Clone for Value {1155	fn clone(&self) -> Self {1156		with_default_context(|c, _| unsafe { value_incref(c, self.0) })1157			.expect("value incref should not fail");1158		Self(self.0)1159	}1160}1161impl Drop for Value {1162	fn drop(&mut self) {1163		with_default_context(|c, _| unsafe { value_decref(c, self.0) })1164			.expect("value drop should not fail");1165	}1166}11671168static TOKIO_FOR_NIX: OnceLock<Arc<tokio::runtime::Runtime>> = OnceLock::new();11691170pub fn init_libraries() {1171	unsafe { GC_allow_register_threads() };11721173	let mut ctx = NixContext::new();1174	ctx.run_in_context(|c| unsafe { libutil_init(c) })1175		.expect("util init should not fail");1176	ctx.run_in_context(|c| unsafe { libstore_init(c) })1177		.expect("store init should not fail");1178	ctx.run_in_context(|c| unsafe { libexpr_init(c) })1179		.expect("expr init should not fail");11801181	nix_logging_cxx::apply_tracing_logger();1182}11831184pub fn init_tokio_for_nix(tokio: Arc<tokio::runtime::Runtime>) {1185	TOKIO_FOR_NIX1186		.set(tokio)1187		.expect("tokio for nix should only be initialized once");1188}11891190pub fn await_in_nix<F: Send + 'static>(f: impl Future<Output = F> + Send + 'static) -> F {1191	// It should be possible to do Handle::current(), but some of the planned features don't work well with that1192	let runtime = TOKIO_FOR_NIX1193		.get()1194		.expect("init_tokio_for_nix was not called");1195	std::thread::spawn(move || runtime.block_on(f))1196		.join()1197		.expect("await_in_nix inner thread panicked")1198}11991200unsafe extern "C" fn nix_primop_closure_adapter<const N: usize>(1201	user_data: *mut c_void,1202	mut context: *mut c_context,1203	state: *mut nix_raw::EvalState,1204	args: *mut *mut value,1205	ret: *mut value,1206) {1207	let user_closure: &UserClosure<N> = unsafe { &*user_data.cast_const().cast() };1208	let args: [&Value; N] = array::from_fn(|i| {1209		let v: &mut Value = unsafe { &mut *args.add(i).cast() };1210		v as &Value1211	});1212	let ctx: &mut NixContext = unsafe { transmute(&mut context) };12131214	let state: &EvalState = unsafe { std::mem::transmute(&state) };12151216	match user_closure(state, args) {1217		Ok(v) => {1218			unsafe { copy_value(context, ret, v.0) };1219		}1220		Err(e) => {1221			ctx.set_err(e);1222		}1223	}1224}12251226type UserClosure<const N: usize> = Box<dyn Fn(&EvalState, [&Value; N]) -> Result<Value>>;12271228pub struct NativeFn(*mut PrimOp);1229impl NativeFn {1230	pub fn new<const N: usize>(1231		name: &'static CStr,1232		doc: &'static CStr,1233		args: [&'static CStr; N],1234		f: impl Fn(&EvalState, [&Value; N]) -> Result<Value> + 'static,1235	) -> Self {1236		// Double-boxing to make it thin pointer, as vtable gets outside of first Box1237		let closure: Box<UserClosure<N>> = Box::new(Box::new(f));1238		let f: PrimOpFun = Some(nix_primop_closure_adapter::<N>);1239		let mut args = args.into_iter().map(|v| v.as_ptr()).collect_vec();1240		args.push(null());1241		let args = args.as_mut_ptr();1242		let primop = unsafe {1243			alloc_primop(1244				null_mut(),1245				f,1246				N as i32,1247				name.as_ptr(),1248				args,1249				doc.as_ptr(),1250				Box::into_raw(closure).cast(),1251			)1252		};12531254		assert!(!primop.is_null(), "primop allocation should not fail");12551256		Self(primop)1257	}1258	pub fn register(self) {1259		unsafe { register_primop(null_mut(), self.0) };1260	}1261}12621263pub struct StorePath(*mut c_store_path);1264impl StorePath {1265	fn as_ptr(&self) -> *mut c_store_path {1266		self.01267	}1268}12691270impl Drop for StorePath {1271	fn drop(&mut self) {1272		unsafe { store_path_free(self.0) }1273	}1274}12751276#[test_log::test]1277fn test_native() -> Result<()> {1278	init_libraries();1279	NativeFn::new(1280		c"__uppercaseSuffix2",1281		c"make string uppercase and add suffix",1282		[c"str", c"suffix"],1283		|_, [str, suffix]: [&Value; 2]| {1284			let str = str.to_string()?;1285			let suffix = suffix.to_string()?;1286			Ok(Value::new_str(&format!("{}{suffix}", str.to_uppercase())))1287		},1288	)1289	.register();12901291	let mut fetch_settings = FetchSettings::new();1292	fetch_settings.set(c"warn-dirty", c"false");12931294	let manifest = format!("git+file://{}/../../", env!("CARGO_MANIFEST_DIR"));1295	let flake = FlakeSettings::new()?;1296	let parse = FlakeReferenceParseFlags::new(&flake)?;1297	let (mut r, _) = FlakeReference::new(&manifest, &flake, &parse, &fetch_settings)?;1298	let lock = FlakeLockFlags::new(&flake)?;1299	let locked = r.lock(&fetch_settings, &flake, &lock)?;1300	let attrs = locked.get_attrs(&mut FlakeSettings::new()?)?;13011302	let builtins = Value::eval("builtins")?;1303	assert_eq!(builtins.type_of(), NixType::Attrs);13041305	assert_eq!(attrs.type_of(), NixType::Attrs);1306	let test_data = nix_go!(attrs.testData);13071308	let test_string: String = nix_go_json!(test_data.testString);1309	assert_eq!(test_string, "hello");13101311	let s = nix_go!(attrs.packages["x86_64-linux"].fleet.drvPath);1312	let s = CString::new(s.to_string()?).expect("path str is cstring");13131314	let uppercase_suffix = Value::new_primop(NativeFn::new(1315		c"uppercase_suffix",1316		c"make string uppercase and add suffix",1317		[c"str", c"suffix"],1318		|es, [str, suffix]: [&Value; 2]| {1319			let str = str.to_string()?;1320			let suffix = suffix.to_string()?;1321			Ok(Value::new_str(&format!("{}{suffix}", str.to_uppercase())))1322		},1323	));13241325	let test_result: String = nix_go_json!(test_data.testPrimop(uppercase_suffix));1326	assert_eq!(test_result, "PREFIX_BODY_SUFFIX");1327	let test_result: String = nix_go_json!(builtins.uppercaseSuffix2("test")("suffix"));1328	assert_eq!(test_result, "TESTsuffix");13291330	let drv_path =1331		nix_go!(attrs.packages["x86_64-linux"]["fleet-install-secrets"].drvPath).to_string()?;1332	let graph = drv::DrvGraph::resolve(&drv_path)?;1333	eprintln!(1334		"fleet-install-secrets dependency graph: {} nodes",1335		graph.nodes.len()1336	);1337	for (path, node) in &graph.nodes {1338		if !node.input_drvs.is_empty() {1339			eprintln!("  {} ({} deps)", node.name, node.input_drvs.len());1340		}1341	}13421343	Ok(())1344}13451346// pub struct GcAlloc;1347// unsafe impl GlobalAlloc for GcAlloc {1348// 	unsafe fn alloc(&self, l: Layout) -> *mut u8 {1349// 		let ptr = unsafe { GC_malloc(l.size()) };1350// 		ptr.cast()1351// 	}1352// 	unsafe fn dealloc(&self, ptr: *mut u8, _: Layout) {1353// 		// unsafe { GC_free(ptr.cast()) };1354// 	}1355//1356// 	unsafe fn realloc(&self, ptr: *mut u8, _: Layout, new_size: usize) -> *mut u8 {1357// 		let ptr = unsafe { GC_realloc(ptr.cast(), new_size) };1358// 		ptr.cast()1359// 	}1360// }1361//1362// #[global_allocator]1363// static GC: GcAlloc = GcAlloc;