1pub mod wit;
2
3use crate::ExtensionManifest;
4use crate::capability_granter::CapabilityGranter;
5use anyhow::{Context as _, Result, anyhow, bail};
6use async_trait::async_trait;
7use dap::{DebugRequest, StartDebuggingRequestArgumentsRequest};
8use extension::{
9 CodeLabel, Command, Completion, ContextServerConfiguration, DebugAdapterBinary,
10 DebugTaskDefinition, ExtensionCapability, ExtensionHostProxy, KeyValueStoreDelegate,
11 ProcessExecCapability, ProjectDelegate, SlashCommand, SlashCommandArgumentCompletion,
12 SlashCommandOutput, Symbol, WorktreeDelegate,
13};
14use fs::{Fs, normalize_path};
15use futures::future::LocalBoxFuture;
16use futures::{
17 Future, FutureExt, StreamExt as _,
18 channel::{
19 mpsc::{self, UnboundedSender},
20 oneshot,
21 },
22 future::BoxFuture,
23};
24use gpui::{App, AsyncApp, BackgroundExecutor, Task, Timer};
25use http_client::HttpClient;
26use language::LanguageName;
27use lsp::LanguageServerName;
28use moka::sync::Cache;
29use node_runtime::NodeRuntime;
30use release_channel::ReleaseChannel;
31use semantic_version::SemanticVersion;
32use std::borrow::Cow;
33use std::sync::{LazyLock, OnceLock};
34use std::time::Duration;
35use std::{
36 path::{Path, PathBuf},
37 sync::Arc,
38};
39use task::{DebugScenario, SpawnInTerminal, TaskTemplate, ZedDebugConfig};
40use wasmtime::{
41 CacheStore, Engine, Store,
42 component::{Component, ResourceTable},
43};
44use wasmtime_wasi::{self as wasi, WasiView};
45use wit::Extension;
46
47pub struct WasmHost {
48 engine: Engine,
49 release_channel: ReleaseChannel,
50 http_client: Arc<dyn HttpClient>,
51 node_runtime: NodeRuntime,
52 pub(crate) proxy: Arc<ExtensionHostProxy>,
53 fs: Arc<dyn Fs>,
54 pub work_dir: PathBuf,
55 /// The capabilities granted to extensions running on the host.
56 pub(crate) granted_capabilities: Vec<ExtensionCapability>,
57 _main_thread_message_task: Task<()>,
58 main_thread_message_tx: mpsc::UnboundedSender<MainThreadCall>,
59}
60
61#[derive(Clone, Debug)]
62pub struct WasmExtension {
63 tx: UnboundedSender<ExtensionCall>,
64 pub manifest: Arc<ExtensionManifest>,
65 pub work_dir: Arc<Path>,
66 #[allow(unused)]
67 pub zed_api_version: SemanticVersion,
68}
69
70impl Drop for WasmExtension {
71 fn drop(&mut self) {
72 self.tx.close_channel();
73 }
74}
75
76#[async_trait]
77impl extension::Extension for WasmExtension {
78 fn manifest(&self) -> Arc<ExtensionManifest> {
79 self.manifest.clone()
80 }
81
82 fn work_dir(&self) -> Arc<Path> {
83 self.work_dir.clone()
84 }
85
86 async fn language_server_command(
87 &self,
88 language_server_id: LanguageServerName,
89 language_name: LanguageName,
90 worktree: Arc<dyn WorktreeDelegate>,
91 ) -> Result<Command> {
92 self.call(|extension, store| {
93 async move {
94 let resource = store.data_mut().table().push(worktree)?;
95 let command = extension
96 .call_language_server_command(
97 store,
98 &language_server_id,
99 &language_name,
100 resource,
101 )
102 .await?
103 .map_err(|err| store.data().extension_error(err))?;
104
105 Ok(command.into())
106 }
107 .boxed()
108 })
109 .await
110 }
111
112 async fn language_server_initialization_options(
113 &self,
114 language_server_id: LanguageServerName,
115 language_name: LanguageName,
116 worktree: Arc<dyn WorktreeDelegate>,
117 ) -> Result<Option<String>> {
118 self.call(|extension, store| {
119 async move {
120 let resource = store.data_mut().table().push(worktree)?;
121 let options = extension
122 .call_language_server_initialization_options(
123 store,
124 &language_server_id,
125 &language_name,
126 resource,
127 )
128 .await?
129 .map_err(|err| store.data().extension_error(err))?;
130 anyhow::Ok(options)
131 }
132 .boxed()
133 })
134 .await
135 }
136
137 async fn language_server_workspace_configuration(
138 &self,
139 language_server_id: LanguageServerName,
140 worktree: Arc<dyn WorktreeDelegate>,
141 ) -> Result<Option<String>> {
142 self.call(|extension, store| {
143 async move {
144 let resource = store.data_mut().table().push(worktree)?;
145 let options = extension
146 .call_language_server_workspace_configuration(
147 store,
148 &language_server_id,
149 resource,
150 )
151 .await?
152 .map_err(|err| store.data().extension_error(err))?;
153 anyhow::Ok(options)
154 }
155 .boxed()
156 })
157 .await
158 }
159
160 async fn language_server_additional_initialization_options(
161 &self,
162 language_server_id: LanguageServerName,
163 target_language_server_id: LanguageServerName,
164 worktree: Arc<dyn WorktreeDelegate>,
165 ) -> Result<Option<String>> {
166 self.call(|extension, store| {
167 async move {
168 let resource = store.data_mut().table().push(worktree)?;
169 let options = extension
170 .call_language_server_additional_initialization_options(
171 store,
172 &language_server_id,
173 &target_language_server_id,
174 resource,
175 )
176 .await?
177 .map_err(|err| store.data().extension_error(err))?;
178 anyhow::Ok(options)
179 }
180 .boxed()
181 })
182 .await
183 }
184
185 async fn language_server_additional_workspace_configuration(
186 &self,
187 language_server_id: LanguageServerName,
188 target_language_server_id: LanguageServerName,
189 worktree: Arc<dyn WorktreeDelegate>,
190 ) -> Result<Option<String>> {
191 self.call(|extension, store| {
192 async move {
193 let resource = store.data_mut().table().push(worktree)?;
194 let options = extension
195 .call_language_server_additional_workspace_configuration(
196 store,
197 &language_server_id,
198 &target_language_server_id,
199 resource,
200 )
201 .await?
202 .map_err(|err| store.data().extension_error(err))?;
203 anyhow::Ok(options)
204 }
205 .boxed()
206 })
207 .await
208 }
209
210 async fn labels_for_completions(
211 &self,
212 language_server_id: LanguageServerName,
213 completions: Vec<Completion>,
214 ) -> Result<Vec<Option<CodeLabel>>> {
215 self.call(|extension, store| {
216 async move {
217 let labels = extension
218 .call_labels_for_completions(
219 store,
220 &language_server_id,
221 completions.into_iter().map(Into::into).collect(),
222 )
223 .await?
224 .map_err(|err| store.data().extension_error(err))?;
225
226 Ok(labels
227 .into_iter()
228 .map(|label| label.map(Into::into))
229 .collect())
230 }
231 .boxed()
232 })
233 .await
234 }
235
236 async fn labels_for_symbols(
237 &self,
238 language_server_id: LanguageServerName,
239 symbols: Vec<Symbol>,
240 ) -> Result<Vec<Option<CodeLabel>>> {
241 self.call(|extension, store| {
242 async move {
243 let labels = extension
244 .call_labels_for_symbols(
245 store,
246 &language_server_id,
247 symbols.into_iter().map(Into::into).collect(),
248 )
249 .await?
250 .map_err(|err| store.data().extension_error(err))?;
251
252 Ok(labels
253 .into_iter()
254 .map(|label| label.map(Into::into))
255 .collect())
256 }
257 .boxed()
258 })
259 .await
260 }
261
262 async fn complete_slash_command_argument(
263 &self,
264 command: SlashCommand,
265 arguments: Vec<String>,
266 ) -> Result<Vec<SlashCommandArgumentCompletion>> {
267 self.call(|extension, store| {
268 async move {
269 let completions = extension
270 .call_complete_slash_command_argument(store, &command.into(), &arguments)
271 .await?
272 .map_err(|err| store.data().extension_error(err))?;
273
274 Ok(completions.into_iter().map(Into::into).collect())
275 }
276 .boxed()
277 })
278 .await
279 }
280
281 async fn run_slash_command(
282 &self,
283 command: SlashCommand,
284 arguments: Vec<String>,
285 delegate: Option<Arc<dyn WorktreeDelegate>>,
286 ) -> Result<SlashCommandOutput> {
287 self.call(|extension, store| {
288 async move {
289 let resource = if let Some(delegate) = delegate {
290 Some(store.data_mut().table().push(delegate)?)
291 } else {
292 None
293 };
294
295 let output = extension
296 .call_run_slash_command(store, &command.into(), &arguments, resource)
297 .await?
298 .map_err(|err| store.data().extension_error(err))?;
299
300 Ok(output.into())
301 }
302 .boxed()
303 })
304 .await
305 }
306
307 async fn context_server_command(
308 &self,
309 context_server_id: Arc<str>,
310 project: Arc<dyn ProjectDelegate>,
311 ) -> Result<Command> {
312 self.call(|extension, store| {
313 async move {
314 let project_resource = store.data_mut().table().push(project)?;
315 let command = extension
316 .call_context_server_command(store, context_server_id.clone(), project_resource)
317 .await?
318 .map_err(|err| store.data().extension_error(err))?;
319 anyhow::Ok(command.into())
320 }
321 .boxed()
322 })
323 .await
324 }
325
326 async fn context_server_configuration(
327 &self,
328 context_server_id: Arc<str>,
329 project: Arc<dyn ProjectDelegate>,
330 ) -> Result<Option<ContextServerConfiguration>> {
331 self.call(|extension, store| {
332 async move {
333 let project_resource = store.data_mut().table().push(project)?;
334 let Some(configuration) = extension
335 .call_context_server_configuration(
336 store,
337 context_server_id.clone(),
338 project_resource,
339 )
340 .await?
341 .map_err(|err| store.data().extension_error(err))?
342 else {
343 return Ok(None);
344 };
345
346 Ok(Some(configuration.try_into()?))
347 }
348 .boxed()
349 })
350 .await
351 }
352
353 async fn suggest_docs_packages(&self, provider: Arc<str>) -> Result<Vec<String>> {
354 self.call(|extension, store| {
355 async move {
356 let packages = extension
357 .call_suggest_docs_packages(store, provider.as_ref())
358 .await?
359 .map_err(|err| store.data().extension_error(err))?;
360
361 Ok(packages)
362 }
363 .boxed()
364 })
365 .await
366 }
367
368 async fn index_docs(
369 &self,
370 provider: Arc<str>,
371 package_name: Arc<str>,
372 kv_store: Arc<dyn KeyValueStoreDelegate>,
373 ) -> Result<()> {
374 self.call(|extension, store| {
375 async move {
376 let kv_store_resource = store.data_mut().table().push(kv_store)?;
377 extension
378 .call_index_docs(
379 store,
380 provider.as_ref(),
381 package_name.as_ref(),
382 kv_store_resource,
383 )
384 .await?
385 .map_err(|err| store.data().extension_error(err))?;
386
387 anyhow::Ok(())
388 }
389 .boxed()
390 })
391 .await
392 }
393
394 async fn get_dap_binary(
395 &self,
396 dap_name: Arc<str>,
397 config: DebugTaskDefinition,
398 user_installed_path: Option<PathBuf>,
399 worktree: Arc<dyn WorktreeDelegate>,
400 ) -> Result<DebugAdapterBinary> {
401 self.call(|extension, store| {
402 async move {
403 let resource = store.data_mut().table().push(worktree)?;
404 let dap_binary = extension
405 .call_get_dap_binary(store, dap_name, config, user_installed_path, resource)
406 .await?
407 .map_err(|err| store.data().extension_error(err))?;
408 let dap_binary = dap_binary.try_into()?;
409 Ok(dap_binary)
410 }
411 .boxed()
412 })
413 .await
414 }
415 async fn dap_request_kind(
416 &self,
417 dap_name: Arc<str>,
418 config: serde_json::Value,
419 ) -> Result<StartDebuggingRequestArgumentsRequest> {
420 self.call(|extension, store| {
421 async move {
422 let kind = extension
423 .call_dap_request_kind(store, dap_name, config)
424 .await?
425 .map_err(|err| store.data().extension_error(err))?;
426 Ok(kind.into())
427 }
428 .boxed()
429 })
430 .await
431 }
432
433 async fn dap_config_to_scenario(&self, config: ZedDebugConfig) -> Result<DebugScenario> {
434 self.call(|extension, store| {
435 async move {
436 let kind = extension
437 .call_dap_config_to_scenario(store, config)
438 .await?
439 .map_err(|err| store.data().extension_error(err))?;
440 Ok(kind)
441 }
442 .boxed()
443 })
444 .await
445 }
446
447 async fn dap_locator_create_scenario(
448 &self,
449 locator_name: String,
450 build_config_template: TaskTemplate,
451 resolved_label: String,
452 debug_adapter_name: String,
453 ) -> Result<Option<DebugScenario>> {
454 self.call(|extension, store| {
455 async move {
456 extension
457 .call_dap_locator_create_scenario(
458 store,
459 locator_name,
460 build_config_template,
461 resolved_label,
462 debug_adapter_name,
463 )
464 .await
465 }
466 .boxed()
467 })
468 .await
469 }
470 async fn run_dap_locator(
471 &self,
472 locator_name: String,
473 config: SpawnInTerminal,
474 ) -> Result<DebugRequest> {
475 self.call(|extension, store| {
476 async move {
477 extension
478 .call_run_dap_locator(store, locator_name, config)
479 .await?
480 .map_err(|err| store.data().extension_error(err))
481 }
482 .boxed()
483 })
484 .await
485 }
486}
487
488pub struct WasmState {
489 manifest: Arc<ExtensionManifest>,
490 pub table: ResourceTable,
491 ctx: wasi::WasiCtx,
492 pub host: Arc<WasmHost>,
493 pub(crate) capability_granter: CapabilityGranter,
494}
495
496type MainThreadCall = Box<dyn Send + for<'a> FnOnce(&'a mut AsyncApp) -> LocalBoxFuture<'a, ()>>;
497
498type ExtensionCall = Box<
499 dyn Send + for<'a> FnOnce(&'a mut Extension, &'a mut Store<WasmState>) -> BoxFuture<'a, ()>,
500>;
501
502fn wasm_engine(executor: &BackgroundExecutor) -> wasmtime::Engine {
503 static WASM_ENGINE: OnceLock<wasmtime::Engine> = OnceLock::new();
504 WASM_ENGINE
505 .get_or_init(|| {
506 let mut config = wasmtime::Config::new();
507 config.wasm_component_model(true);
508 config.async_support(true);
509 config
510 .enable_incremental_compilation(cache_store())
511 .unwrap();
512 // Async support introduces the issue that extension execution happens during `Future::poll`,
513 // which could block an async thread.
514 // https://docs.rs/wasmtime/latest/wasmtime/struct.Config.html#execution-in-poll
515 //
516 // Epoch interruption is a lightweight mechanism to allow the extensions to yield control
517 // back to the executor at regular intervals.
518 config.epoch_interruption(true);
519
520 let engine = wasmtime::Engine::new(&config).unwrap();
521
522 // It might be safer to do this on a non-async thread to make sure it makes progress
523 // regardless of if extensions are blocking.
524 // However, due to our current setup, this isn't a likely occurrence and we'd rather
525 // not have a dedicated thread just for this. If it becomes an issue, we can consider
526 // creating a separate thread for epoch interruption.
527 let engine_ref = engine.weak();
528 executor
529 .spawn(async move {
530 // Somewhat arbitrary interval, as it isn't a guaranteed interval.
531 // But this is a rough upper bound for how long the extension execution can block on
532 // `Future::poll`.
533 const EPOCH_INTERVAL: Duration = Duration::from_millis(100);
534 let mut timer = Timer::interval(EPOCH_INTERVAL);
535 while let Some(_) = timer.next().await {
536 // Exit the loop and thread once the engine is dropped.
537 let Some(engine) = engine_ref.upgrade() else {
538 break;
539 };
540 engine.increment_epoch();
541 }
542 })
543 .detach();
544
545 engine
546 })
547 .clone()
548}
549
550fn cache_store() -> Arc<IncrementalCompilationCache> {
551 static CACHE_STORE: LazyLock<Arc<IncrementalCompilationCache>> =
552 LazyLock::new(|| Arc::new(IncrementalCompilationCache::new()));
553 CACHE_STORE.clone()
554}
555
556impl WasmHost {
557 pub fn new(
558 fs: Arc<dyn Fs>,
559 http_client: Arc<dyn HttpClient>,
560 node_runtime: NodeRuntime,
561 proxy: Arc<ExtensionHostProxy>,
562 work_dir: PathBuf,
563 cx: &mut App,
564 ) -> Arc<Self> {
565 let (tx, mut rx) = mpsc::unbounded::<MainThreadCall>();
566 let task = cx.spawn(async move |cx| {
567 while let Some(message) = rx.next().await {
568 message(cx).await;
569 }
570 });
571 Arc::new(Self {
572 engine: wasm_engine(cx.background_executor()),
573 fs,
574 work_dir,
575 http_client,
576 node_runtime,
577 proxy,
578 release_channel: ReleaseChannel::global(cx),
579 granted_capabilities: vec![ExtensionCapability::ProcessExec(ProcessExecCapability {
580 command: "*".to_string(),
581 args: vec!["**".to_string()],
582 })],
583 _main_thread_message_task: task,
584 main_thread_message_tx: tx,
585 })
586 }
587
588 pub fn load_extension(
589 self: &Arc<Self>,
590 wasm_bytes: Vec<u8>,
591 manifest: &Arc<ExtensionManifest>,
592 executor: BackgroundExecutor,
593 ) -> Task<Result<WasmExtension>> {
594 let this = self.clone();
595 let manifest = manifest.clone();
596 executor.clone().spawn(async move {
597 let zed_api_version = parse_wasm_extension_version(&manifest.id, &wasm_bytes)?;
598
599 let component = Component::from_binary(&this.engine, &wasm_bytes)
600 .context("failed to compile wasm component")?;
601
602 let mut store = wasmtime::Store::new(
603 &this.engine,
604 WasmState {
605 ctx: this.build_wasi_ctx(&manifest).await?,
606 manifest: manifest.clone(),
607 table: ResourceTable::new(),
608 host: this.clone(),
609 capability_granter: CapabilityGranter::new(
610 this.granted_capabilities.clone(),
611 manifest.clone(),
612 ),
613 },
614 );
615 // Store will yield after 1 tick, and get a new deadline of 1 tick after each yield.
616 store.set_epoch_deadline(1);
617 store.epoch_deadline_async_yield_and_update(1);
618
619 let mut extension = Extension::instantiate_async(
620 &executor,
621 &mut store,
622 this.release_channel,
623 zed_api_version,
624 &component,
625 )
626 .await?;
627
628 extension
629 .call_init_extension(&mut store)
630 .await
631 .context("failed to initialize wasm extension")?;
632
633 let (tx, mut rx) = mpsc::unbounded::<ExtensionCall>();
634 executor
635 .spawn(async move {
636 while let Some(call) = rx.next().await {
637 (call)(&mut extension, &mut store).await;
638 }
639 })
640 .detach();
641
642 Ok(WasmExtension {
643 manifest: manifest.clone(),
644 work_dir: this.work_dir.join(manifest.id.as_ref()).into(),
645 tx,
646 zed_api_version,
647 })
648 })
649 }
650
651 async fn build_wasi_ctx(&self, manifest: &Arc<ExtensionManifest>) -> Result<wasi::WasiCtx> {
652 let extension_work_dir = self.work_dir.join(manifest.id.as_ref());
653 self.fs
654 .create_dir(&extension_work_dir)
655 .await
656 .context("failed to create extension work dir")?;
657
658 let file_perms = wasi::FilePerms::all();
659 let dir_perms = wasi::DirPerms::all();
660
661 Ok(wasi::WasiCtxBuilder::new()
662 .inherit_stdio()
663 .preopened_dir(&extension_work_dir, ".", dir_perms, file_perms)?
664 .preopened_dir(
665 &extension_work_dir,
666 extension_work_dir.to_string_lossy(),
667 dir_perms,
668 file_perms,
669 )?
670 .env("PWD", extension_work_dir.to_string_lossy())
671 .env("RUST_BACKTRACE", "full")
672 .build())
673 }
674
675 pub fn writeable_path_from_extension(&self, id: &Arc<str>, path: &Path) -> Result<PathBuf> {
676 let extension_work_dir = self.work_dir.join(id.as_ref());
677 let path = normalize_path(&extension_work_dir.join(path));
678 anyhow::ensure!(
679 path.starts_with(&extension_work_dir),
680 "cannot write to path {path:?}",
681 );
682 Ok(path)
683 }
684}
685
686pub fn parse_wasm_extension_version(
687 extension_id: &str,
688 wasm_bytes: &[u8],
689) -> Result<SemanticVersion> {
690 let mut version = None;
691
692 for part in wasmparser::Parser::new(0).parse_all(wasm_bytes) {
693 if let wasmparser::Payload::CustomSection(s) =
694 part.context("error parsing wasm extension")?
695 {
696 if s.name() == "zed:api-version" {
697 version = parse_wasm_extension_version_custom_section(s.data());
698 if version.is_none() {
699 bail!(
700 "extension {} has invalid zed:api-version section: {:?}",
701 extension_id,
702 s.data()
703 );
704 }
705 }
706 }
707 }
708
709 // The reason we wait until we're done parsing all of the Wasm bytes to return the version
710 // is to work around a panic that can happen inside of Wasmtime when the bytes are invalid.
711 //
712 // By parsing the entirety of the Wasm bytes before we return, we're able to detect this problem
713 // earlier as an `Err` rather than as a panic.
714 version.with_context(|| format!("extension {extension_id} has no zed:api-version section"))
715}
716
717fn parse_wasm_extension_version_custom_section(data: &[u8]) -> Option<SemanticVersion> {
718 if data.len() == 6 {
719 Some(SemanticVersion::new(
720 u16::from_be_bytes([data[0], data[1]]) as _,
721 u16::from_be_bytes([data[2], data[3]]) as _,
722 u16::from_be_bytes([data[4], data[5]]) as _,
723 ))
724 } else {
725 None
726 }
727}
728
729impl WasmExtension {
730 pub async fn load(
731 extension_dir: &Path,
732 manifest: &Arc<ExtensionManifest>,
733 wasm_host: Arc<WasmHost>,
734 cx: &AsyncApp,
735 ) -> Result<Self> {
736 let path = extension_dir.join("extension.wasm");
737
738 let mut wasm_file = wasm_host
739 .fs
740 .open_sync(&path)
741 .await
742 .context("failed to open wasm file")?;
743
744 let mut wasm_bytes = Vec::new();
745 wasm_file
746 .read_to_end(&mut wasm_bytes)
747 .context("failed to read wasm")?;
748
749 wasm_host
750 .load_extension(wasm_bytes, manifest, cx.background_executor().clone())
751 .await
752 .with_context(|| format!("failed to load wasm extension {}", manifest.id))
753 }
754
755 pub async fn call<T, Fn>(&self, f: Fn) -> T
756 where
757 T: 'static + Send,
758 Fn: 'static
759 + Send
760 + for<'a> FnOnce(&'a mut Extension, &'a mut Store<WasmState>) -> BoxFuture<'a, T>,
761 {
762 let (return_tx, return_rx) = oneshot::channel();
763 self.tx
764 .unbounded_send(Box::new(move |extension, store| {
765 async {
766 let result = f(extension, store).await;
767 return_tx.send(result).ok();
768 }
769 .boxed()
770 }))
771 .expect("wasm extension channel should not be closed yet");
772 return_rx.await.expect("wasm extension channel")
773 }
774}
775
776impl WasmState {
777 fn on_main_thread<T, Fn>(&self, f: Fn) -> impl 'static + Future<Output = T>
778 where
779 T: 'static + Send,
780 Fn: 'static + Send + for<'a> FnOnce(&'a mut AsyncApp) -> LocalBoxFuture<'a, T>,
781 {
782 let (return_tx, return_rx) = oneshot::channel();
783 self.host
784 .main_thread_message_tx
785 .clone()
786 .unbounded_send(Box::new(move |cx| {
787 async {
788 let result = f(cx).await;
789 return_tx.send(result).ok();
790 }
791 .boxed_local()
792 }))
793 .expect("main thread message channel should not be closed yet");
794 async move { return_rx.await.expect("main thread message channel") }
795 }
796
797 fn work_dir(&self) -> PathBuf {
798 self.host.work_dir.join(self.manifest.id.as_ref())
799 }
800
801 fn extension_error(&self, message: String) -> anyhow::Error {
802 anyhow!(
803 "from extension \"{}\" version {}: {}",
804 self.manifest.name,
805 self.manifest.version,
806 message
807 )
808 }
809}
810
811impl wasi::WasiView for WasmState {
812 fn table(&mut self) -> &mut ResourceTable {
813 &mut self.table
814 }
815
816 fn ctx(&mut self) -> &mut wasi::WasiCtx {
817 &mut self.ctx
818 }
819}
820
821/// Wrapper around a mini-moka bounded cache for storing incremental compilation artifacts.
822/// Since wasm modules have many similar elements, this can save us a lot of work at the
823/// cost of a small memory footprint. However, we don't want this to be unbounded, so we use
824/// a LFU/LRU cache to evict less used cache entries.
825#[derive(Debug)]
826struct IncrementalCompilationCache {
827 cache: Cache<Vec<u8>, Vec<u8>>,
828}
829
830impl IncrementalCompilationCache {
831 fn new() -> Self {
832 let cache = Cache::builder()
833 // Cap this at 32 MB for now. Our extensions turn into roughly 512kb in the cache,
834 // which means we could store 64 completely novel extensions in the cache, but in
835 // practice we will more than that, which is more than enough for our use case.
836 .max_capacity(32 * 1024 * 1024)
837 .weigher(|k: &Vec<u8>, v: &Vec<u8>| (k.len() + v.len()).try_into().unwrap_or(u32::MAX))
838 .build();
839 Self { cache }
840 }
841}
842
843impl CacheStore for IncrementalCompilationCache {
844 fn get(&self, key: &[u8]) -> Option<Cow<'_, [u8]>> {
845 self.cache.get(key).map(|v| v.into())
846 }
847
848 fn insert(&self, key: &[u8], value: Vec<u8>) -> bool {
849 self.cache.insert(key.to_vec(), value);
850 true
851 }
852}