1use crate::wasm_host::parse_wasm_extension_version;
2use crate::ExtensionManifest;
3use crate::{extension_manifest::ExtensionLibraryKind, GrammarManifestEntry};
4use anyhow::{anyhow, bail, Context as _, Result};
5use async_compression::futures::bufread::GzipDecoder;
6use async_tar::Archive;
7use futures::io::BufReader;
8use futures::AsyncReadExt;
9use serde::Deserialize;
10use std::{
11 env, fs, mem,
12 path::{Path, PathBuf},
13 process::{Command, Stdio},
14 sync::Arc,
15};
16use util::http::{self, AsyncBody, HttpClient};
17use wasm_encoder::{ComponentSectionId, Encode as _, RawSection, Section as _};
18use wasmparser::Parser;
19use wit_component::ComponentEncoder;
20
21/// Currently, we compile with Rust's `wasm32-wasi` target, which works with WASI `preview1`.
22/// But the WASM component model is based on WASI `preview2`. So we need an 'adapter' WASM
23/// module, which implements the `preview1` interface in terms of `preview2`.
24///
25/// Once Rust 1.78 is released, there will be a `wasm32-wasip2` target available, so we will
26/// not need the adapter anymore.
27const RUST_TARGET: &str = "wasm32-wasi";
28const WASI_ADAPTER_URL: &str =
29 "https://github.com/bytecodealliance/wasmtime/releases/download/v18.0.2/wasi_snapshot_preview1.reactor.wasm";
30
31/// Compiling Tree-sitter parsers from C to WASM requires Clang 17, and a WASM build of libc
32/// and clang's runtime library. The `wasi-sdk` provides these binaries.
33///
34/// Once Clang 17 and its wasm target are available via system package managers, we won't need
35/// to download this.
36const WASI_SDK_URL: &str = "https://github.com/WebAssembly/wasi-sdk/releases/download/wasi-sdk-21/";
37const WASI_SDK_ASSET_NAME: Option<&str> = if cfg!(target_os = "macos") {
38 Some("wasi-sdk-21.0-macos.tar.gz")
39} else if cfg!(target_os = "linux") {
40 Some("wasi-sdk-21.0-linux.tar.gz")
41} else if cfg!(target_os = "windows") {
42 Some("wasi-sdk-21.0.m-mingw.tar.gz")
43} else {
44 None
45};
46
47pub struct ExtensionBuilder {
48 cache_dir: PathBuf,
49 pub http: Arc<dyn HttpClient>,
50}
51
52pub struct CompileExtensionOptions {
53 pub release: bool,
54}
55
56#[derive(Deserialize)]
57struct CargoToml {
58 package: CargoTomlPackage,
59}
60
61#[derive(Deserialize)]
62struct CargoTomlPackage {
63 name: String,
64}
65
66impl ExtensionBuilder {
67 pub fn new(cache_dir: PathBuf) -> Self {
68 Self {
69 cache_dir,
70 http: http::client(),
71 }
72 }
73
74 pub async fn compile_extension(
75 &self,
76 extension_dir: &Path,
77 extension_manifest: &mut ExtensionManifest,
78 options: CompileExtensionOptions,
79 ) -> Result<()> {
80 populate_defaults(extension_manifest, &extension_dir)?;
81
82 if extension_dir.is_relative() {
83 bail!(
84 "extension dir {} is not an absolute path",
85 extension_dir.display()
86 );
87 }
88
89 fs::create_dir_all(&self.cache_dir).context("failed to create cache dir")?;
90
91 if extension_manifest.lib.kind == Some(ExtensionLibraryKind::Rust) {
92 log::info!("compiling Rust extension {}", extension_dir.display());
93 self.compile_rust_extension(extension_dir, extension_manifest, options)
94 .await
95 .context("failed to compile Rust extension")?;
96 }
97
98 for (grammar_name, grammar_metadata) in &extension_manifest.grammars {
99 self.compile_grammar(extension_dir, grammar_name.as_ref(), grammar_metadata)
100 .await
101 .with_context(|| format!("failed to compile grammar '{grammar_name}'"))?;
102 }
103
104 log::info!("finished compiling extension {}", extension_dir.display());
105 Ok(())
106 }
107
108 async fn compile_rust_extension(
109 &self,
110 extension_dir: &Path,
111 manifest: &mut ExtensionManifest,
112 options: CompileExtensionOptions,
113 ) -> Result<(), anyhow::Error> {
114 self.install_rust_wasm_target_if_needed()?;
115 let adapter_bytes = self.install_wasi_preview1_adapter_if_needed().await?;
116
117 let cargo_toml_content = fs::read_to_string(&extension_dir.join("Cargo.toml"))?;
118 let cargo_toml: CargoToml = toml::from_str(&cargo_toml_content)?;
119
120 log::info!("compiling rust extension {}", extension_dir.display());
121 let output = Command::new("cargo")
122 .args(["build", "--target", RUST_TARGET])
123 .args(options.release.then_some("--release"))
124 .arg("--target-dir")
125 .arg(extension_dir.join("target"))
126 .current_dir(&extension_dir)
127 .output()
128 .context("failed to run `cargo`")?;
129 if !output.status.success() {
130 bail!(
131 "failed to build extension {}",
132 String::from_utf8_lossy(&output.stderr)
133 );
134 }
135
136 let mut wasm_path = PathBuf::from(extension_dir);
137 wasm_path.extend([
138 "target",
139 RUST_TARGET,
140 if options.release { "release" } else { "debug" },
141 &cargo_toml
142 .package
143 .name
144 // The wasm32-wasi target normalizes `-` in package names to `_` in the resulting `.wasm` file.
145 .replace('-', "_"),
146 ]);
147 wasm_path.set_extension("wasm");
148
149 let wasm_bytes = fs::read(&wasm_path)
150 .with_context(|| format!("failed to read output module `{}`", wasm_path.display()))?;
151
152 let encoder = ComponentEncoder::default()
153 .module(&wasm_bytes)?
154 .adapter("wasi_snapshot_preview1", &adapter_bytes)
155 .context("failed to load adapter module")?
156 .validate(true);
157
158 let component_bytes = encoder
159 .encode()
160 .context("failed to encode wasm component")?;
161
162 let component_bytes = self
163 .strip_custom_sections(&component_bytes)
164 .context("failed to strip debug sections from wasm component")?;
165
166 let wasm_extension_api_version =
167 parse_wasm_extension_version(&manifest.id, &component_bytes)
168 .context("compiled wasm did not contain a valid zed extension api version")?;
169 manifest.lib.version = Some(wasm_extension_api_version);
170
171 fs::write(extension_dir.join("extension.wasm"), &component_bytes)
172 .context("failed to write extension.wasm")?;
173
174 Ok(())
175 }
176
177 async fn compile_grammar(
178 &self,
179 extension_dir: &Path,
180 grammar_name: &str,
181 grammar_metadata: &GrammarManifestEntry,
182 ) -> Result<()> {
183 let clang_path = self.install_wasi_sdk_if_needed().await?;
184
185 let mut grammar_repo_dir = extension_dir.to_path_buf();
186 grammar_repo_dir.extend(["grammars", grammar_name]);
187
188 let mut grammar_wasm_path = grammar_repo_dir.clone();
189 grammar_wasm_path.set_extension("wasm");
190
191 log::info!("checking out {grammar_name} parser");
192 self.checkout_repo(
193 &grammar_repo_dir,
194 &grammar_metadata.repository,
195 &grammar_metadata.rev,
196 )?;
197
198 let src_path = grammar_repo_dir.join("src");
199 let parser_path = src_path.join("parser.c");
200 let scanner_path = src_path.join("scanner.c");
201
202 log::info!("compiling {grammar_name} parser");
203 let clang_output = Command::new(&clang_path)
204 .args(["-fPIC", "-shared", "-Os"])
205 .arg(format!("-Wl,--export=tree_sitter_{grammar_name}"))
206 .arg("-o")
207 .arg(&grammar_wasm_path)
208 .arg("-I")
209 .arg(&src_path)
210 .arg(&parser_path)
211 .args(scanner_path.exists().then_some(scanner_path))
212 .output()
213 .context("failed to run clang")?;
214 if !clang_output.status.success() {
215 bail!(
216 "failed to compile {} parser with clang: {}",
217 grammar_name,
218 String::from_utf8_lossy(&clang_output.stderr),
219 );
220 }
221
222 Ok(())
223 }
224
225 fn checkout_repo(&self, directory: &Path, url: &str, rev: &str) -> Result<()> {
226 let git_dir = directory.join(".git");
227
228 if directory.exists() {
229 let remotes_output = Command::new("git")
230 .arg("--git-dir")
231 .arg(&git_dir)
232 .args(["remote", "-v"])
233 .output()?;
234 let has_remote = remotes_output.status.success()
235 && String::from_utf8_lossy(&remotes_output.stdout)
236 .lines()
237 .any(|line| {
238 let mut parts = line.split(|c: char| c.is_whitespace());
239 parts.next() == Some("origin") && parts.any(|part| part == url)
240 });
241 if !has_remote {
242 bail!(
243 "grammar directory '{}' already exists, but is not a git clone of '{}'",
244 directory.display(),
245 url
246 );
247 }
248 } else {
249 fs::create_dir_all(&directory).with_context(|| {
250 format!("failed to create grammar directory {}", directory.display(),)
251 })?;
252 let init_output = Command::new("git")
253 .arg("init")
254 .current_dir(&directory)
255 .output()?;
256 if !init_output.status.success() {
257 bail!(
258 "failed to run `git init` in directory '{}'",
259 directory.display()
260 );
261 }
262
263 let remote_add_output = Command::new("git")
264 .arg("--git-dir")
265 .arg(&git_dir)
266 .args(["remote", "add", "origin", url])
267 .output()
268 .context("failed to execute `git remote add`")?;
269 if !remote_add_output.status.success() {
270 bail!(
271 "failed to add remote {url} for git repository {}",
272 git_dir.display()
273 );
274 }
275 }
276
277 let fetch_output = Command::new("git")
278 .arg("--git-dir")
279 .arg(&git_dir)
280 .args(["fetch", "--depth", "1", "origin", &rev])
281 .output()
282 .context("failed to execute `git fetch`")?;
283
284 let checkout_output = Command::new("git")
285 .arg("--git-dir")
286 .arg(&git_dir)
287 .args(["checkout", &rev])
288 .current_dir(&directory)
289 .output()
290 .context("failed to execute `git checkout`")?;
291 if !checkout_output.status.success() {
292 if !fetch_output.status.success() {
293 bail!(
294 "failed to fetch revision {} in directory '{}'",
295 rev,
296 directory.display()
297 );
298 }
299 bail!(
300 "failed to checkout revision {} in directory '{}': {}",
301 rev,
302 directory.display(),
303 String::from_utf8_lossy(&checkout_output.stderr)
304 );
305 }
306
307 Ok(())
308 }
309
310 fn install_rust_wasm_target_if_needed(&self) -> Result<()> {
311 let rustc_output = Command::new("rustc")
312 .arg("--print")
313 .arg("sysroot")
314 .output()
315 .context("failed to run rustc")?;
316 if !rustc_output.status.success() {
317 bail!(
318 "failed to retrieve rust sysroot: {}",
319 String::from_utf8_lossy(&rustc_output.stderr)
320 );
321 }
322
323 let sysroot = PathBuf::from(String::from_utf8(rustc_output.stdout)?.trim());
324 if sysroot.join("lib/rustlib").join(RUST_TARGET).exists() {
325 return Ok(());
326 }
327
328 let output = Command::new("rustup")
329 .args(["target", "add", RUST_TARGET])
330 .stderr(Stdio::inherit())
331 .stdout(Stdio::inherit())
332 .output()
333 .context("failed to run `rustup target add`")?;
334 if !output.status.success() {
335 bail!("failed to install the `{RUST_TARGET}` target");
336 }
337
338 Ok(())
339 }
340
341 async fn install_wasi_preview1_adapter_if_needed(&self) -> Result<Vec<u8>> {
342 let cache_path = self.cache_dir.join("wasi_snapshot_preview1.reactor.wasm");
343 if let Ok(content) = fs::read(&cache_path) {
344 if Parser::is_core_wasm(&content) {
345 return Ok(content);
346 }
347 }
348
349 fs::remove_file(&cache_path).ok();
350
351 log::info!(
352 "downloading wasi adapter module to {}",
353 cache_path.display()
354 );
355 let mut response = self
356 .http
357 .get(WASI_ADAPTER_URL, AsyncBody::default(), true)
358 .await?;
359
360 let mut content = Vec::new();
361 let mut body = BufReader::new(response.body_mut());
362 body.read_to_end(&mut content).await?;
363
364 fs::write(&cache_path, &content)
365 .with_context(|| format!("failed to save file {}", cache_path.display()))?;
366
367 if !Parser::is_core_wasm(&content) {
368 bail!("downloaded wasi adapter is invalid");
369 }
370 Ok(content)
371 }
372
373 async fn install_wasi_sdk_if_needed(&self) -> Result<PathBuf> {
374 let url = if let Some(asset_name) = WASI_SDK_ASSET_NAME {
375 format!("{WASI_SDK_URL}/{asset_name}")
376 } else {
377 bail!("wasi-sdk is not available for platform {}", env::consts::OS);
378 };
379
380 let wasi_sdk_dir = self.cache_dir.join("wasi-sdk");
381 let mut clang_path = wasi_sdk_dir.clone();
382 clang_path.extend(["bin", &format!("clang{}", env::consts::EXE_SUFFIX)]);
383
384 if fs::metadata(&clang_path).map_or(false, |metadata| metadata.is_file()) {
385 return Ok(clang_path);
386 }
387
388 let mut tar_out_dir = wasi_sdk_dir.clone();
389 tar_out_dir.set_extension("archive");
390
391 fs::remove_dir_all(&wasi_sdk_dir).ok();
392 fs::remove_dir_all(&tar_out_dir).ok();
393
394 log::info!("downloading wasi-sdk to {}", wasi_sdk_dir.display());
395 let mut response = self.http.get(&url, AsyncBody::default(), true).await?;
396 let body = BufReader::new(response.body_mut());
397 let body = GzipDecoder::new(body);
398 let tar = Archive::new(body);
399 tar.unpack(&tar_out_dir)
400 .await
401 .context("failed to unpack wasi-sdk archive")?;
402
403 let inner_dir = fs::read_dir(&tar_out_dir)?
404 .next()
405 .ok_or_else(|| anyhow!("no content"))?
406 .context("failed to read contents of extracted wasi archive directory")?
407 .path();
408 fs::rename(&inner_dir, &wasi_sdk_dir).context("failed to move extracted wasi dir")?;
409 fs::remove_dir_all(&tar_out_dir).ok();
410
411 Ok(clang_path)
412 }
413
414 // This was adapted from:
415 // https://github.com/bytecodealliance/wasm-tools/1791a8f139722e9f8679a2bd3d8e423e55132b22/src/bin/wasm-tools/strip.rs
416 fn strip_custom_sections(&self, input: &Vec<u8>) -> Result<Vec<u8>> {
417 use wasmparser::Payload::*;
418
419 let strip_custom_section = |name: &str| name.starts_with(".debug");
420
421 let mut output = Vec::new();
422 let mut stack = Vec::new();
423
424 for payload in Parser::new(0).parse_all(input) {
425 let payload = payload?;
426
427 // Track nesting depth, so that we don't mess with inner producer sections:
428 match payload {
429 Version { encoding, .. } => {
430 output.extend_from_slice(match encoding {
431 wasmparser::Encoding::Component => &wasm_encoder::Component::HEADER,
432 wasmparser::Encoding::Module => &wasm_encoder::Module::HEADER,
433 });
434 }
435 ModuleSection { .. } | ComponentSection { .. } => {
436 stack.push(mem::take(&mut output));
437 continue;
438 }
439 End { .. } => {
440 let mut parent = match stack.pop() {
441 Some(c) => c,
442 None => break,
443 };
444 if output.starts_with(&wasm_encoder::Component::HEADER) {
445 parent.push(ComponentSectionId::Component as u8);
446 output.encode(&mut parent);
447 } else {
448 parent.push(ComponentSectionId::CoreModule as u8);
449 output.encode(&mut parent);
450 }
451 output = parent;
452 }
453 _ => {}
454 }
455
456 match &payload {
457 CustomSection(c) => {
458 if strip_custom_section(c.name()) {
459 continue;
460 }
461 }
462
463 _ => {}
464 }
465
466 if let Some((id, range)) = payload.as_section() {
467 RawSection {
468 id,
469 data: &input[range],
470 }
471 .append_to(&mut output);
472 }
473 }
474
475 Ok(output)
476 }
477}
478
479fn populate_defaults(manifest: &mut ExtensionManifest, extension_path: &Path) -> Result<()> {
480 // For legacy extensions on the v0 schema (aka, using `extension.json`), clear out any existing
481 // contents of the computed fields, since we don't care what the existing values are.
482 if manifest.schema_version.is_v0() {
483 manifest.languages.clear();
484 manifest.grammars.clear();
485 manifest.themes.clear();
486 }
487
488 let cargo_toml_path = extension_path.join("Cargo.toml");
489 if cargo_toml_path.exists() {
490 manifest.lib.kind = Some(ExtensionLibraryKind::Rust);
491 }
492
493 let languages_dir = extension_path.join("languages");
494 if languages_dir.exists() {
495 for entry in fs::read_dir(&languages_dir).context("failed to list languages dir")? {
496 let entry = entry?;
497 let language_dir = entry.path();
498 let config_path = language_dir.join("config.toml");
499 if config_path.exists() {
500 let relative_language_dir =
501 language_dir.strip_prefix(extension_path)?.to_path_buf();
502 if !manifest.languages.contains(&relative_language_dir) {
503 manifest.languages.push(relative_language_dir);
504 }
505 }
506 }
507 }
508
509 let themes_dir = extension_path.join("themes");
510 if themes_dir.exists() {
511 for entry in fs::read_dir(&themes_dir).context("failed to list themes dir")? {
512 let entry = entry?;
513 let theme_path = entry.path();
514 if theme_path.extension() == Some("json".as_ref()) {
515 let relative_theme_path = theme_path.strip_prefix(extension_path)?.to_path_buf();
516 if !manifest.themes.contains(&relative_theme_path) {
517 manifest.themes.push(relative_theme_path);
518 }
519 }
520 }
521 }
522
523 // For legacy extensions on the v0 schema (aka, using `extension.json`), we want to populate the grammars in
524 // the manifest using the contents of the `grammars` directory.
525 if manifest.schema_version.is_v0() {
526 let grammars_dir = extension_path.join("grammars");
527 if grammars_dir.exists() {
528 for entry in fs::read_dir(&grammars_dir).context("failed to list grammars dir")? {
529 let entry = entry?;
530 let grammar_path = entry.path();
531 if grammar_path.extension() == Some("toml".as_ref()) {
532 #[derive(Deserialize)]
533 struct GrammarConfigToml {
534 pub repository: String,
535 pub commit: String,
536 }
537
538 let grammar_config = fs::read_to_string(&grammar_path)?;
539 let grammar_config: GrammarConfigToml = toml::from_str(&grammar_config)?;
540
541 let grammar_name = grammar_path
542 .file_stem()
543 .and_then(|stem| stem.to_str())
544 .ok_or_else(|| anyhow!("no grammar name"))?;
545 if !manifest.grammars.contains_key(grammar_name) {
546 manifest.grammars.insert(
547 grammar_name.into(),
548 GrammarManifestEntry {
549 repository: grammar_config.repository,
550 rev: grammar_config.commit,
551 },
552 );
553 }
554 }
555 }
556 }
557 }
558
559 Ok(())
560}