WASM runtime switch to import memory (#4737)

* WASM runtime switch to import memory Up to now runtimes have exported their memory. To unify it with sandboxing, this pr switches runtimes to import memory as well. From a functional perspective, exporting/importing memory makes no difference to the runtime. To provide backwards compatibility, WASM exported memory is still supported. * Revert debug stuff * Revert some stuff
2026-04-26 22:47:56 +00:00 · 2020-01-28 09:36:57 +01:00
parent 5c8743510e
commit 793a1eb053
15 changed files with 603 additions and 428 deletions
@@ -25,7 +25,10 @@
 //!
 //! For more information see <https://crates.io/substrate-wasm-builder>

-use std::{env, process::{Command, self}, fs, path::{PathBuf, Path}};
+use std::{
+	env, process::{Command, self}, fs, path::{PathBuf, Path}, hash::{Hash, Hasher},
+	collections::hash_map::DefaultHasher,
+};

 /// Environment variable that tells us to skip building the WASM binary.
 const SKIP_BUILD_ENV: &str = "SKIP_WASM_BUILD";
@@ -47,6 +50,225 @@ fn replace_back_slashes<T: ToString>(path: T) -> String {
 	path.to_string().replace("\\", "/")
 }

+/// Returns the manifest dir from the `CARGO_MANIFEST_DIR` env.
+fn get_manifest_dir() -> PathBuf {
+	env::var("CARGO_MANIFEST_DIR")
+		.expect("`CARGO_MANIFEST_DIR` is always set for `build.rs` files; qed")
+		.into()
+}
+
+/// First step of the [`WasmBuilder`] to select the project to build.
+pub struct WasmBuilderSelectProject {
+	/// This parameter just exists to make it impossible to construct
+	/// this type outside of this crate.
+	_ignore: (),
+}
+
+impl WasmBuilderSelectProject {
+	/// Use the current project as project for building the WASM binary.
+	///
+	/// # Panics
+	///
+	/// Panics if the `CARGO_MANIFEST_DIR` variable is not set. This variable
+	/// is always set by `Cargo` in `build.rs` files.
+	pub fn with_current_project(self) -> WasmBuilderSelectSource {
+		WasmBuilderSelectSource(get_manifest_dir().join("Cargo.toml"))
+	}
+
+	/// Use the given `path` as project for building the WASM binary.
+	///
+	/// Returns an error if the given `path` does not points to a `Cargo.toml`.
+	pub fn with_project(
+		self,
+		path: impl Into<PathBuf>,
+	) -> Result<WasmBuilderSelectSource, &'static str> {
+		let path = path.into();
+
+		if path.ends_with("Cargo.toml") {
+			Ok(WasmBuilderSelectSource(path))
+		} else {
+			Err("Project path must point to the `Cargo.toml` of the project")
+		}
+	}
+}
+
+/// Second step of the [`WasmBuilder`] to set the source of the `wasm-builder`.
+pub struct WasmBuilderSelectSource(PathBuf);
+
+impl WasmBuilderSelectSource {
+	/// Use the given `path` as source for `wasm-builder`.
+	///
+	/// The `path` must be relative and point to the directory that contains the `Cargo.toml` for
+	/// `wasm-builder`.
+	pub fn with_wasm_builder_from_path(self, path: &'static str) -> WasmBuilder {
+		WasmBuilder {
+			source: WasmBuilderSource::Path(path),
+			rust_flags: Vec::new(),
+			file_name: None,
+			project_cargo_toml: self.0,
+		}
+	}
+
+	/// Use the given `repo` and `rev` as source for `wasm-builder`.
+	pub fn with_wasm_builder_from_git(self, repo: &'static str, rev: &'static str) -> WasmBuilder {
+		WasmBuilder {
+			source: WasmBuilderSource::Git { repo, rev },
+			rust_flags: Vec::new(),
+			file_name: None,
+			project_cargo_toml: self.0,
+		}
+	}
+
+	/// Use the given `version` to fetch `wasm-builder` source from crates.io.
+	pub fn with_wasm_builder_from_crates(self, version: &'static str) -> WasmBuilder {
+		WasmBuilder {
+			source: WasmBuilderSource::Crates(version),
+			rust_flags: Vec::new(),
+			file_name: None,
+			project_cargo_toml: self.0,
+		}
+	}
+
+	/// Use the given `version` to fetch `wasm-builder` source from crates.io or use
+	/// the given `path` as source.
+	///
+	/// The `path` must be relative and point to the directory that contains the `Cargo.toml` for
+	/// `wasm-builder`.
+	pub fn with_wasm_builder_from_crates_or_path(
+		self,
+		version: &'static str,
+		path: &'static str,
+	) -> WasmBuilder {
+		WasmBuilder {
+			source: WasmBuilderSource::CratesOrPath { version, path },
+			rust_flags: Vec::new(),
+			file_name: None,
+			project_cargo_toml: self.0,
+		}
+	}
+
+	/// Use the given `source` as source for `wasm-builder`.
+	pub fn with_wasm_builder_source(self, source: WasmBuilderSource) -> WasmBuilder {
+		WasmBuilder {
+			source,
+			rust_flags: Vec::new(),
+			file_name: None,
+			project_cargo_toml: self.0,
+		}
+	}
+}
+
+/// The builder for building a wasm binary.
+///
+/// The builder itself is seperated into multiple structs to make the setup type safe.
+///
+/// Building a wasm binary:
+///
+/// 1. Call [`WasmBuilder::new`] to create a new builder.
+/// 2. Select the project to build using the methods of [`WasmBuilderSelectProject`].
+/// 3. Select the source of the `wasm-builder` crate using the methods of
+///    [`WasmBuilderSelectSource`].
+/// 4. Set additional `RUST_FLAGS` or a different name for the file containing the WASM code
+///    using methods of [`Self`].
+/// 5. Build the WASM binary using [`Self::build`].
+pub struct WasmBuilder {
+	/// Where should we pull the `wasm-builder` crate from.
+	source: WasmBuilderSource,
+	/// Flags that should be appended to `RUST_FLAGS` env variable.
+	rust_flags: Vec<String>,
+	/// The name of the file that is being generated in `OUT_DIR`.
+	///
+	/// Defaults to `wasm_binary.rs`.
+	file_name: Option<String>,
+	/// The path to the `Cargo.toml` of the project that should be build
+	/// for wasm.
+	project_cargo_toml: PathBuf,
+}
+
+impl WasmBuilder {
+	/// Create a new instance of the builder.
+	pub fn new() -> WasmBuilderSelectProject {
+		WasmBuilderSelectProject {
+			_ignore: (),
+		}
+	}
+
+	/// Enable exporting `__heap_base` as global variable in the WASM binary.
+	///
+	/// This adds `-Clink-arg=--export=__heap_base` to `RUST_FLAGS`.
+	pub fn export_heap_base(mut self) -> Self {
+		self.rust_flags.push("-Clink-arg=--export=__heap_base".into());
+		self
+	}
+
+	/// Set the name of the file that will be generated in `OUT_DIR`.
+	///
+	/// This file needs to be included to get access to the build WASM binary.
+	///
+	/// If this function is not called, `file_name` defaults to `wasm_binary.rs`
+	pub fn set_file_name(mut self, file_name: impl Into<String>) -> Self {
+		self.file_name = Some(file_name.into());
+		self
+	}
+
+	/// Instruct the linker to import the memory into the WASM binary.
+	///
+	/// This adds `-C link-arg=--import-memory` to `RUST_FLAGS`.
+	pub fn import_memory(mut self) -> Self {
+		self.rust_flags.push("-C link-arg=--import-memory".into());
+		self
+	}
+
+	/// Append the given `flag` to `RUST_FLAGS`.
+	///
+	/// `flag` is appended as is, so it needs to be a valid flag.
+	pub fn append_to_rust_flags(mut self, flag: impl Into<String>) -> Self {
+		self.rust_flags.push(flag.into());
+		self
+	}
+
+	/// Build the WASM binary.
+	pub fn build(self) {
+		if check_skip_build() {
+			// If we skip the build, we still want to make sure to be called when an env variable
+			// changes
+			generate_rerun_if_changed_instructions();
+			return;
+		}
+
+		let out_dir = PathBuf::from(env::var("OUT_DIR").expect("`OUT_DIR` is set by cargo!"));
+		let file_path = out_dir.join(self.file_name.unwrap_or_else(|| "wasm_binary.rs".into()));
+
+		// Hash the path to the project cargo toml.
+		let mut hasher = DefaultHasher::new();
+		self.project_cargo_toml.hash(&mut hasher);
+
+		let project_name = env::var("CARGO_PKG_NAME").expect("`CARGO_PKG_NAME` is set by cargo!");
+		// Make sure the `wasm-builder-runner` path is unique by concatenating the name of the
+		// project that is compiling the WASM binary with the hash of the path to the project that
+		// should be compiled as WASM binary.
+		let project_folder = get_workspace_root()
+			.join(format!("{}{}", project_name, hasher.finish()));
+
+		if check_provide_dummy_wasm_binary() {
+			provide_dummy_wasm_binary(&file_path);
+		} else {
+			create_project(
+				&project_folder,
+				&file_path,
+				self.source,
+				&self.project_cargo_toml,
+				&self.rust_flags.into_iter().map(|f| format!("{} ", f)).collect::<String>(),
+			);
+			run_project(&project_folder);
+		}
+
+		// As last step we need to generate our `rerun-if-changed` stuff. If a build fails, we don't
+		// want to spam the output!
+		generate_rerun_if_changed_instructions();
+	}
+}
+
 /// The `wasm-builder` dependency source.
 pub enum WasmBuilderSource {
 	/// The relative path to the source code from the current manifest dir.
@@ -96,46 +318,21 @@ impl WasmBuilderSource {
 /// Build the currently built project as WASM binary and extend `RUSTFLAGS` with the given rustflags.
 ///
 /// For more information, see [`build_current_project`].
+#[deprecated(
+	since = "1.0.5",
+	note = "Please switch to [`WasmBuilder`]",
+)]
 pub fn build_current_project_with_rustflags(
 	file_name: &str,
 	wasm_builder_source: WasmBuilderSource,
-	default_rustflags: &str,
+	default_rust_flags: &str,
 ) {
-	if check_skip_build() {
-		// If we skip the build, we still want to make sure to be called when an env variable changes
-		generate_rerun_if_changed_instructions();
-		return;
-	}
-
-	let manifest_dir = PathBuf::from(
-		env::var("CARGO_MANIFEST_DIR").expect(
-			"`CARGO_MANIFEST_DIR` is always set for `build.rs` files; qed"
-		)
-	);
-
-	let cargo_toml_path = manifest_dir.join("Cargo.toml");
-	let out_dir = PathBuf::from(env::var("OUT_DIR").expect("`OUT_DIR` is set by cargo!"));
-	let file_path = out_dir.join(file_name);
-	let project_name = env::var("CARGO_PKG_NAME").expect("`CARGO_PKG_NAME` is set by cargo!");
-	let project_folder = get_workspace_root().join(project_name);
-
-	if check_provide_dummy_wasm_binary() {
-		provide_dummy_wasm_binary(&file_path);
-	} else {
-		create_project(
-			&project_folder,
-			&file_path,
-			&manifest_dir,
-			wasm_builder_source,
-			&cargo_toml_path,
-			default_rustflags,
-		);
-		run_project(&project_folder);
-	}
-
-	// As last step we need to generate our `rerun-if-changed` stuff. If a build fails, we don't
-	// want to spam the output!
-	generate_rerun_if_changed_instructions();
+	WasmBuilder::new()
+		.with_current_project()
+		.with_wasm_builder_source(wasm_builder_source)
+		.append_to_rust_flags(default_rust_flags)
+		.set_file_name(file_name)
+		.build()
 }

 /// Build the currently built project as WASM binary.
@@ -145,7 +342,12 @@ pub fn build_current_project_with_rustflags(
 /// `file_name` - The name of the file being generated in the `OUT_DIR`. The file contains the
 ///               constant `WASM_BINARY` which contains the build wasm binary.
 /// `wasm_builder_path` - Path to the wasm-builder project, relative to `CARGO_MANIFEST_DIR`.
+#[deprecated(
+	since = "1.0.5",
+	note = "Please switch to [`WasmBuilder`]",
+)]
 pub fn build_current_project(file_name: &str, wasm_builder_source: WasmBuilderSource) {
+	#[allow(deprecated)]
 	build_current_project_with_rustflags(file_name, wasm_builder_source, "");
 }

@@ -171,7 +373,6 @@ fn get_workspace_root() -> PathBuf {
 fn create_project(
 	project_folder: &Path,
 	file_path: &Path,
-	manifest_dir: &Path,
 	wasm_builder_source: WasmBuilderSource,
 	cargo_toml_path: &Path,
 	default_rustflags: &str,
@@ -193,7 +394,7 @@ fn create_project(

 				[workspace]
 			"#,
-			wasm_builder_source = wasm_builder_source.to_cargo_source(manifest_dir),
+			wasm_builder_source = wasm_builder_source.to_cargo_source(&get_manifest_dir()),
 		)
 	).expect("WASM build runner `Cargo.toml` writing can not fail; qed");