Move build logic to lib (#97)

* refactored out build to lib

* save_raw returns

* fix indentations and other small fixes

* fix build API

* rename Target to SourceTarget

* fix formatting

* make join runtime_type into runtime_type and runtime_version

cli/build/main.rs

@@ -9,13 +9,11 @@ extern crate pwasm_utils_cli as logger;
 mod source;
 
 use std::{fs, io};
-use std::io::Write;
 use std::path::PathBuf;
 
 use clap::{App, Arg};
 use parity_wasm::elements;
-
-use utils::{CREATE_SYMBOL, CALL_SYMBOL, ununderscore_funcs, externalize_mem, shrink_unknown_stack};
+use utils::{build, BuildError, SourceTarget};
 
 #[derive(Debug)]
 pub enum Error {
@@ -23,38 +21,18 @@ pub enum Error {
 	FailedToCopy(String),
 	Decoding(elements::Error, String),
 	Encoding(elements::Error),
-	Packing(utils::PackingError),
-	Optimizer,
-}
-
-impl From<io::Error> for Error {
-	fn from(err: io::Error) -> Self {
-		Error::Io(err)
-	}
-}
-
-impl From<utils::OptimizerError> for Error {
-	fn from(_err: utils::OptimizerError) -> Self {
-		Error::Optimizer
-	}
-}
-
-impl From<utils::PackingError> for Error {
-	fn from(err: utils::PackingError) -> Self {
-		Error::Packing(err)
-	}
+	Build(BuildError),
 }
 
 impl std::fmt::Display for Error {
 	fn fmt(&self, f: &mut std::fmt::Formatter) -> Result<(), std::fmt::Error> {
-		use Error::*;
+		use self::Error::*;
 		match *self {
 			Io(ref io) => write!(f, "Generic i/o error: {}", io),
 			FailedToCopy(ref msg) => write!(f, "{}. Have you tried to run \"cargo build\"?", msg),
 			Decoding(ref err, ref file) => write!(f, "Decoding error ({}). Must be a valid wasm file {}. Pointed wrong file?", err, file),
 			Encoding(ref err) => write!(f, "Encoding error ({}). Almost impossible to happen, no free disk space?", err),
-			Optimizer => write!(f, "Optimization error due to missing export section. Pointed wrong file?"),
-			Packing(ref e) => write!(f, "Packing failed due to module structure error: {}. Sure used correct libraries for building contracts?", e),
+			Build(ref err) => write!(f, "Build error: {}", err)
 		}
 	}
 }
@@ -70,8 +48,8 @@ pub fn process_output(input: &source::SourceInput) -> Result<(), Error> {
 	let wasm_name = input.bin_name().to_string().replace("-", "_");
 	cargo_path.push(
 		match input.target() {
-			source::SourceTarget::Emscripten => source::EMSCRIPTEN_TRIPLET,
-			source::SourceTarget::Unknown => source::UNKNOWN_TRIPLET,
+			SourceTarget::Emscripten => source::EMSCRIPTEN_TRIPLET,
+			SourceTarget::Unknown => source::UNKNOWN_TRIPLET,
 		}
 	);
 	cargo_path.push("release");
@@ -87,14 +65,6 @@ pub fn process_output(input: &source::SourceInput) -> Result<(), Error> {
 	Ok(())
 }
 
-fn has_ctor(module: &elements::Module) -> bool {
-	if let Some(ref section) = module.export_section() {
-		section.entries().iter().any(|e| CREATE_SYMBOL == e.field())
-	} else {
-		false
-	}
-}
-
 fn do_main() -> Result<(), Error> {
 	logger::init_log();
 
@@ -166,71 +136,48 @@ fn do_main() -> Result<(), Error> {
 
 	let path = wasm_path(&source_input);
 
-	let mut module = parity_wasm::deserialize_file(&path)
+	let module = parity_wasm::deserialize_file(&path)
 		.map_err(|e| Error::Decoding(e, path.to_string()))?;
 
-	if let source::SourceTarget::Emscripten = source_input.target() {
-		module = ununderscore_funcs(module);
-	}
-
-	if let source::SourceTarget::Unknown = source_input.target() {
-		// 49152 is 48kb!
-		if matches.is_present("enforce_stack_adjustment") {
-			let stack_size: u32 = matches.value_of("shrink_stack").unwrap_or_else(|| "49152").parse().expect("New stack size is not valid u32");
-			assert!(stack_size <= 1024*1024);
-			let (new_module, new_stack_top) = shrink_unknown_stack(module, 1024 * 1024 - stack_size);
-			module = new_module;
-			let mut stack_top_page = new_stack_top / 65536;
-			if new_stack_top % 65536 > 0 { stack_top_page += 1 };
-			module = externalize_mem(module, Some(stack_top_page), 16);
-		} else {
-			module = externalize_mem(module, None, 16);
-		}
-	}
-
-	if let Some(runtime_type) = matches.value_of("runtime_type") {
-		let runtime_type: &[u8] = runtime_type.as_bytes();
-		if runtime_type.len() != 4 {
+	let runtime_type_version = if let (Some(runtime_type), Some(runtime_version))
+		 = (matches.value_of("runtime_type"), matches.value_of("runtime_version")) {
+		let mut ty: [u8; 4] = Default::default();
+		let runtime_bytes = runtime_type.as_bytes();
+		if runtime_bytes.len() != 4 {
 			panic!("--runtime-type should be equal to 4 bytes");
 		}
-		let runtime_version: u32 = matches.value_of("runtime_version").unwrap_or("1").parse()
+		ty.copy_from_slice(runtime_bytes);
+		let version: u32 = runtime_version.parse()
 			.expect("--runtime-version should be a positive integer");
-		module = utils::inject_runtime_type(module, &runtime_type, runtime_version);
-	}
+		Some((ty, version))
+	} else {
+		None
+	};
 
-	let mut ctor_module = module.clone();
-
-	let mut public_api_entries = matches.value_of("public_api")
+	let public_api_entries = matches.value_of("public_api")
 		.map(|val| val.split(",").collect())
 		.unwrap_or(Vec::new());
-	public_api_entries.push(CALL_SYMBOL);
-	if !matches.is_present("skip_optimization") {
-		utils::optimize(
-			&mut module,
-			public_api_entries,
-		)?;
-	}
+
+	let (module, ctor_module) = build(
+		module,
+		true,
+		source_input.target(),
+		runtime_type_version,
+		&public_api_entries,
+		matches.is_present("enforce_stack_adjustment"),
+		matches.value_of("shrink_stack").unwrap_or_else(|| "49152").parse()
+			.expect("New stack size is not valid u32"),
+		matches.is_present("skip_optimization"),
+	).map_err(Error::Build)?;
 
 	if let Some(save_raw_path) = matches.value_of("save_raw") {
 		parity_wasm::serialize_to_file(save_raw_path, module.clone()).map_err(Error::Encoding)?;
 	}
 
-	let raw_module = parity_wasm::serialize(module).map_err(Error::Encoding)?;
-
-	// If module has an exported function with name=CREATE_SYMBOL
-	// build will pack the module (raw_module) into this funciton and export as CALL_SYMBOL.
-	// Otherwise it will just save an optimised raw_module
-	if has_ctor(&ctor_module) {
-		if !matches.is_present("skip_optimization") {
-			utils::optimize(&mut ctor_module, vec![CREATE_SYMBOL])?;
-		}
-		let ctor_module = utils::pack_instance(raw_module, ctor_module)?;
-		parity_wasm::serialize_to_file(&path, ctor_module).map_err(Error::Encoding)?;
-	} else {
-		let mut file = fs::File::create(&path)?;
-		file.write_all(&raw_module)?;
-	}
-
+	parity_wasm::serialize_to_file(
+		&path,
+		ctor_module.expect("ctor_module can't be None, because 'constructor' argument is set to true in build"),
+	).map_err(Error::Encoding)?;
 	Ok(())
 }
 

cli/build/source.rs

@@ -3,12 +3,7 @@
 pub const UNKNOWN_TRIPLET: &str = "wasm32-unknown-unknown";
 pub const EMSCRIPTEN_TRIPLET: &str = "wasm32-unknown-emscripten";
 
-/// Target configiration of previous build step
-#[derive(Debug, Clone, Copy)]
-pub enum SourceTarget {
-	Emscripten,
-	Unknown,
-}
+use utils::SourceTarget;
 
 /// Configuration of previous build step (cargo compilation)
 #[derive(Debug)]
@@ -59,4 +54,4 @@ impl<'a> SourceInput<'a> {
 	pub fn target(&self) -> SourceTarget {
 		self.target
 	}
-}
+}

src/build.rs

@@ -0,0 +1,123 @@
+use std;
+use super::{
+	CREATE_SYMBOL,
+	CALL_SYMBOL,
+	optimize,
+	pack_instance,
+	ununderscore_funcs,
+	externalize_mem,
+	shrink_unknown_stack,
+	inject_runtime_type,
+	PackingError,
+	OptimizerError,
+};
+use parity_wasm;
+use parity_wasm::elements;
+
+#[derive(Debug)]
+pub enum Error {
+	Encoding(elements::Error),
+	Packing(PackingError),
+	NoCreateSymbolFound,
+	Optimizer,
+}
+
+impl From<OptimizerError> for Error {
+	fn from(_err: OptimizerError) -> Self {
+		Error::Optimizer
+	}
+}
+
+impl From<PackingError> for Error {
+	fn from(err: PackingError) -> Self {
+		Error::Packing(err)
+	}
+}
+
+#[derive(Debug, Clone, Copy)]
+pub enum SourceTarget {
+	Emscripten,
+	Unknown,
+}
+
+impl std::fmt::Display for Error {
+	fn fmt(&self, f: &mut std::fmt::Formatter) -> Result<(), std::fmt::Error> {
+		use self::Error::*;
+		match *self {
+			Encoding(ref err) => write!(f, "Encoding error ({})", err),
+			Optimizer => write!(f, "Optimization error due to missing export section. Pointed wrong file?"),
+			Packing(ref e) => write!(f, "Packing failed due to module structure error: {}. Sure used correct libraries for building contracts?", e),
+			NoCreateSymbolFound => write!(f, "Packing failed: no \"{}\" symbol found?", CREATE_SYMBOL),
+		}
+	}
+}
+
+fn has_ctor(module: &elements::Module) -> bool {
+	if let Some(ref section) = module.export_section() {
+		section.entries().iter().any(|e| CREATE_SYMBOL == e.field())
+	} else {
+		false
+	}
+}
+
+pub fn build(
+	mut module: elements::Module,
+	constructor: bool,
+	source_target: SourceTarget,
+	runtime_type_version: Option<([u8; 4], u32)>,
+	public_api_entries: &[&str],
+	enforce_stack_adjustment: bool,
+	stack_size: u32,
+	skip_optimization: bool,
+) -> Result<(elements::Module, Option<elements::Module>), Error> {
+
+	if let SourceTarget::Emscripten = source_target {
+		module = ununderscore_funcs(module);
+	}
+
+	if let SourceTarget::Unknown = source_target {
+		// 49152 is 48kb!
+		if enforce_stack_adjustment {
+			assert!(stack_size <= 1024*1024);
+			let (new_module, new_stack_top) = shrink_unknown_stack(module, 1024 * 1024 - stack_size);
+			module = new_module;
+			let mut stack_top_page = new_stack_top / 65536;
+			if new_stack_top % 65536 > 0 { stack_top_page += 1 };
+			module = externalize_mem(module, Some(stack_top_page), 16);
+		} else {
+			module = externalize_mem(module, None, 16);
+		}
+	}
+
+	if let Some(runtime_type_version) = runtime_type_version {
+		let (runtime_type, runtime_version) = runtime_type_version;
+		module = inject_runtime_type(module, runtime_type, runtime_version);
+	}
+
+	let mut ctor_module = module.clone();
+
+	let mut public_api_entries = public_api_entries.to_vec();
+	public_api_entries.push(CALL_SYMBOL);
+	if !skip_optimization {
+		optimize(
+			&mut module,
+			public_api_entries,
+		)?;
+	}
+
+	if constructor {
+		if !has_ctor(&ctor_module) {
+			Err(Error::NoCreateSymbolFound)?
+		}
+		if !skip_optimization {
+			optimize(&mut ctor_module, vec![CREATE_SYMBOL])?;
+		}
+		let ctor_module = pack_instance(
+			parity_wasm::serialize(module.clone()).map_err(Error::Encoding)?,
+			ctor_module.clone(),
+		)?;
+		Ok((module, Some(ctor_module)))
+	} else {
+		Ok((module, None))
+	}
+}

src/lib.rs

@@ -15,6 +15,7 @@ pub static RET_SYMBOL: &'static str = "ret";
 
 pub mod rules;
 
+mod build;
 mod optimizer;
 mod gas;
 mod symbols;
@@ -24,6 +25,7 @@ mod runtime_type;
 
 pub mod stack_height;
 
+pub use build::{build, SourceTarget, Error as BuildError};
 pub use optimizer::{optimize, Error as OptimizerError};
 pub use gas::inject_gas_counter;
 pub use ext::{externalize, externalize_mem, underscore_funcs, ununderscore_funcs, shrink_unknown_stack};

src/runtime_type.rs

@@ -2,7 +2,7 @@ use parity_wasm::{elements, builder};
 use self::elements::{ Module, GlobalEntry, External, ExportEntry, GlobalType, ValueType, InitExpr, Instruction, Internal };
 use byteorder::{ LittleEndian, ByteOrder };
 
-pub fn inject_runtime_type(module: Module, runtime_type: &[u8], runtime_version: u32) -> Module {
+pub fn inject_runtime_type(module: Module, runtime_type: [u8; 4], runtime_version: u32) -> Module {
 	let runtime_type: u32 = LittleEndian::read_u32(&runtime_type);
 	let globals_count: u32 = match module.global_section() {
 		Some(ref section) => section.entries().len() as u32,
@@ -33,7 +33,9 @@ mod tests {
 		let mut module = builder::module()
 			.with_global(GlobalEntry::new(GlobalType::new(ValueType::I32, false), InitExpr::new(vec![Instruction::I32Const(42 as i32)])))
 		.build();
-		module = inject_runtime_type(module, b"emcc", 1);
+		let mut runtime_type: [u8; 4] = Default::default();
+		runtime_type.copy_from_slice(b"emcc");
+		module = inject_runtime_type(module, runtime_type, 1);
 		let global_section = module.global_section().expect("Global section expected");
 		assert_eq!(3, global_section.entries().len());
 		let export_section = module.export_section().expect("Export section expected");