resolc crate (#328)

- Factor the YUL crate out of `revive-solidity`.
- `revive-solidity` is in reality not a Solidity implementation but the
revive solidity compiler driver (`resolc`). By renaming we not only get
this straight but also a binary with the same name as the crate which
should be less confusing.

---------

Signed-off-by: Cyrill Leutwiler <bigcyrill@hotmail.com>

crates/resolc/src/process/input.rs

@@ -0,0 +1,51 @@
+//! Process for compiling a single compilation unit.
+//! The input data.
+
+use revive_solc_json_interface::SolcStandardJsonInputSettingsPolkaVMMemory;
+use serde::Deserialize;
+use serde::Serialize;
+
+use crate::project::contract::Contract;
+use crate::project::Project;
+
+/// The input data.
+#[derive(Debug, Serialize, Deserialize)]
+pub struct Input {
+    /// The contract representation.
+    pub contract: Contract,
+    /// The project representation.
+    pub project: Project,
+    /// Whether to append the metadata hash.
+    pub include_metadata_hash: bool,
+    /// The optimizer settings.
+    pub optimizer_settings: revive_llvm_context::OptimizerSettings,
+    /// The debug output config.
+    pub debug_config: revive_llvm_context::DebugConfig,
+    /// The extra LLVM arguments give used for manual control.
+    pub llvm_arguments: Vec<String>,
+    /// The PVM memory configuration.
+    pub memory_config: SolcStandardJsonInputSettingsPolkaVMMemory,
+}
+
+impl Input {
+    /// A shortcut constructor.
+    pub fn new(
+        contract: Contract,
+        project: Project,
+        include_metadata_hash: bool,
+        optimizer_settings: revive_llvm_context::OptimizerSettings,
+        debug_config: revive_llvm_context::DebugConfig,
+        llvm_arguments: Vec<String>,
+        memory_config: SolcStandardJsonInputSettingsPolkaVMMemory,
+    ) -> Self {
+        Self {
+            contract,
+            project,
+            include_metadata_hash,
+            optimizer_settings,
+            debug_config,
+            llvm_arguments,
+            memory_config,
+        }
+    }
+}

crates/resolc/src/process/mod.rs

@@ -0,0 +1,77 @@
+//! Process for compiling a single compilation unit.
+
+pub mod input;
+#[cfg(not(target_os = "emscripten"))]
+pub mod native_process;
+pub mod output;
+#[cfg(target_os = "emscripten")]
+pub mod worker_process;
+
+use std::io::{Read, Write};
+
+use self::input::Input;
+use self::output::Output;
+
+pub trait Process {
+    /// Read input from `stdin`, compile a contract, and write the output to `stdout`.
+    fn run(input_file: Option<&mut std::fs::File>) -> anyhow::Result<()> {
+        let mut stdin = std::io::stdin();
+        let mut stdout = std::io::stdout();
+        let mut stderr = std::io::stderr();
+
+        let mut buffer = Vec::with_capacity(16384);
+        match input_file {
+            Some(ins) => {
+                if let Err(error) = ins.read_to_end(&mut buffer) {
+                    anyhow::bail!("Failed to read recursive process input file: {:?}", error);
+                }
+            }
+            None => {
+                if let Err(error) = stdin.read_to_end(&mut buffer) {
+                    anyhow::bail!(
+                        "Failed to read recursive process input from stdin: {:?}",
+                        error
+                    )
+                }
+            }
+        }
+
+        let input: Input = revive_common::deserialize_from_slice(buffer.as_slice())?;
+
+        revive_llvm_context::initialize_llvm(
+            revive_llvm_context::Target::PVM,
+            crate::DEFAULT_EXECUTABLE_NAME,
+            &input.llvm_arguments,
+        );
+
+        let result = input.contract.compile(
+            input.project,
+            input.optimizer_settings,
+            input.include_metadata_hash,
+            input.debug_config,
+            &input.llvm_arguments,
+            input.memory_config,
+        );
+
+        match result {
+            Ok(build) => {
+                let output = Output::new(build);
+                let json = serde_json::to_vec(&output).expect("Always valid");
+                stdout
+                    .write_all(json.as_slice())
+                    .expect("Stdout writing error");
+                Ok(())
+            }
+            Err(error) => {
+                let message = error.to_string();
+                stderr
+                    .write_all(message.as_bytes())
+                    .expect("Stderr writing error");
+                Err(error)
+            }
+        }
+    }
+
+    /// Runs this process recursively to compile a single contract.
+    fn call(input: Input) -> anyhow::Result<Output>;
+}

crates/resolc/src/process/native_process.rs

@@ -0,0 +1,76 @@
+//! Process for compiling a single compilation unit.
+
+use std::io::Write;
+use std::path::PathBuf;
+use std::process::Command;
+
+use once_cell::sync::OnceCell;
+
+use super::Input;
+use super::Output;
+use super::Process;
+
+/// The overriden executable name used when the compiler is run as a library.
+pub static EXECUTABLE: OnceCell<PathBuf> = OnceCell::new();
+
+pub struct NativeProcess;
+
+impl Process for NativeProcess {
+    fn call(input: Input) -> anyhow::Result<Output> {
+        let input_json = serde_json::to_vec(&input).expect("Always valid");
+
+        let executable = match EXECUTABLE.get() {
+            Some(executable) => executable.to_owned(),
+            None => std::env::current_exe()?,
+        };
+
+        let mut command = Command::new(executable.as_path());
+        command.stdin(std::process::Stdio::piped());
+        command.stdout(std::process::Stdio::piped());
+        command.stderr(std::process::Stdio::piped());
+        command.arg("--recursive-process");
+        let process = command.spawn().map_err(|error| {
+            anyhow::anyhow!("{:?} subprocess spawning error: {:?}", executable, error)
+        })?;
+
+        #[cfg(debug_assertions)]
+        input
+            .debug_config
+            .dump_stage_output(&input.contract.path, Some("stage"), &input_json)
+            .map_err(|error| {
+                anyhow::anyhow!(
+                    "{:?} failed to log the recursive process output: {:?}",
+                    executable,
+                    error,
+                )
+            })?;
+
+        process
+            .stdin
+            .as_ref()
+            .ok_or_else(|| anyhow::anyhow!("{:?} stdin getting error", executable))?
+            .write_all(input_json.as_slice())
+            .map_err(|error| {
+                anyhow::anyhow!("{:?} stdin writing error: {:?}", executable, error)
+            })?;
+        let output = process.wait_with_output().map_err(|error| {
+            anyhow::anyhow!("{:?} subprocess output error: {:?}", executable, error)
+        })?;
+        if !output.status.success() {
+            anyhow::bail!(
+                "{}",
+                String::from_utf8_lossy(output.stderr.as_slice()).to_string(),
+            );
+        }
+
+        let output: Output = revive_common::deserialize_from_slice(output.stdout.as_slice())
+            .map_err(|error| {
+                anyhow::anyhow!(
+                    "{:?} subprocess output parsing error: {}",
+                    executable,
+                    error,
+                )
+            })?;
+        Ok(output)
+    }
+}

crates/resolc/src/process/output.rs

@@ -0,0 +1,21 @@
+//! Process for compiling a single compilation unit.
+//! The output data.
+
+use serde::Deserialize;
+use serde::Serialize;
+
+use crate::build::contract::Contract as ContractBuild;
+
+/// The output data.
+#[derive(Debug, Serialize, Deserialize)]
+pub struct Output {
+    /// The contract build.
+    pub build: ContractBuild,
+}
+
+impl Output {
+    /// A shortcut constructor.
+    pub fn new(build: ContractBuild) -> Self {
+        Self { build }
+    }
+}

crates/resolc/src/process/worker_process.rs

@@ -0,0 +1,69 @@
+//! Process for compiling a single compilation unit using Web Workers.
+
+use std::ffi::{c_char, c_void, CStr, CString};
+
+use super::Input;
+use super::Output;
+use super::Process;
+
+use anyhow::Context;
+use serde::Deserialize;
+
+#[derive(Deserialize)]
+struct Error {
+    message: String,
+}
+
+#[derive(Deserialize)]
+struct Success {
+    data: String,
+}
+
+#[derive(Deserialize)]
+#[serde(tag = "type", rename_all = "snake_case")]
+enum Response {
+    Success(Success),
+    Error(Error),
+}
+
+pub struct WorkerProcess;
+
+impl Process for WorkerProcess {
+    fn call(input: Input) -> anyhow::Result<Output> {
+        let input_json = serde_json::to_vec(&input).expect("Always valid");
+        let input_str = String::from_utf8(input_json).expect("Input shall be valid");
+        // Prepare the input string for the Emscripten function
+        let input_cstring = CString::new(input_str).expect("CString allocation failed");
+
+        // Call the Emscripten function
+        let output_ptr =
+            unsafe { resolc_compile(input_cstring.as_ptr(), input_cstring.as_bytes().len()) };
+
+        // Convert the output pointer back to a Rust string
+        let output_str = unsafe {
+            CStr::from_ptr(output_ptr)
+                .to_str()
+                .with_context(|| "Failed to convert C string to Rust string")
+                .map(str::to_owned)
+        };
+        unsafe { libc::free(output_ptr as *mut c_void) };
+        let output_str = output_str?;
+        let response: Response = serde_json::from_str(&output_str)
+            .map_err(|error| anyhow::anyhow!("Worker output parsing error: {}", error,))?;
+        match response {
+            Response::Success(out) => {
+                let output: Output = revive_common::deserialize_from_slice(out.data.as_bytes())
+                    .map_err(|error| {
+                        anyhow::anyhow!("resolc.js subprocess output parsing error: {}", error,)
+                    })?;
+
+                Ok(output)
+            }
+            Response::Error(err) => anyhow::bail!("Worker error: {}", err.message,),
+        }
+    }
+}
+
+extern "C" {
+    fn resolc_compile(input_ptr: *const c_char, input_len: usize) -> *const c_char;
+}