jam_pvm_builder/
lib.rs

//! Builder logic for creating PVM code blobs for execution on the JAM PVM instances (service code
//! and authorizer code).

#![allow(clippy::unwrap_used)]

const NIGHTLY: &str = "nightly-2024-11-01";

use std::{
	fmt::Display,
	fs,
	path::{Path, PathBuf},
	process::Command,
};

pub enum BlobType {
	Service,
	Authorizer,
}
impl Display for BlobType {
	fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
		match self {
			Self::Service => write!(f, "Service"),
			Self::Authorizer => write!(f, "Authorizer"),
		}
	}
}

impl BlobType {
	pub fn dispatch_table(&self) -> Vec<Vec<u8>> {
		match self {
			Self::Service =>
				vec![b"refine_ext".into(), b"accumulate_ext".into(), b"on_transfer_ext".into()],
			Self::Authorizer => vec![b"is_authorized_ext".into()],
		}
	}
}

/// Build the service crate in `crate_dir` for the RISCV target, convert to PVM code and finish
/// by creating a `<crate_name>.pvm` blob file.
///
/// If used in `build.rs`, then this may be included in the relevant crate by using the `pvm_binary`
/// macro.
pub fn build_service(crate_dir: &Path) {
	let out_dir: PathBuf = std::env::var("OUT_DIR").expect("No OUT_DIR").into();
	println!("cargo:rerun-if-changed={}", crate_dir.to_str().unwrap());
	build_pvm_blob(crate_dir, BlobType::Service, &out_dir, true);
}

/// Build the authorizer crate in `crate_dir` for the RISCV target, convert to PVM code and finish
/// by creating a `<crate_name>.pvm` blob file.
///
/// If used in `build.rs`, then this may be included in the relevant crate by using the `pvm_binary`
/// macro.
pub fn build_authorizer(crate_dir: &Path) {
	let out_dir: PathBuf = std::env::var("OUT_DIR").expect("No OUT_DIR").into();
	println!("cargo:rerun-if-changed={}", crate_dir.to_str().unwrap());
	build_pvm_blob(crate_dir, BlobType::Authorizer, &out_dir, true);
}

fn get_crate_name(crate_dir: &Path) -> String {
	let manifest = Command::new("cargo")
		.current_dir(crate_dir)
		.arg("read-manifest")
		.output()
		.unwrap()
		.stdout;
	serde_json::from_slice::<serde_json::Value>(&manifest)
		.unwrap()
		.get("name")
		.unwrap()
		.as_str()
		.unwrap()
		.to_string()
}

/// Build the PVM crate in `crate_dir` called `crate_name` for the RISCV target, convert to PVM
/// code and finish by creating a `.pvm` blob file of path `output_file`. `out_dir` is used to store
/// any intermediate build files.
pub fn build_pvm_blob(
	crate_dir: &Path,
	blob_type: BlobType,
	out_dir: &Path,
	install_rustc: bool,
) -> (String, PathBuf) {
	let is_64_bit = cfg!(feature = "use-64-bit-pvm");
	let (target_name, target_json_path) = if is_64_bit {
		("riscv64emac-unknown-none-polkavm", polkavm_linker::target_json_64_path().unwrap())
	} else {
		("riscv32emac-unknown-none-polkavm", polkavm_linker::target_json_32_path().unwrap())
	};

	println!("PVM binary type: {}", blob_type);
	println!("Target name: {}", target_name);

	let output = Command::new("rustup")
		.args(["component", "list", "--toolchain", NIGHTLY, "--installed"])
		.output()
		.unwrap_or_else(|_| {
			panic!(
				"Failed to execute `rustup component list --toolchain {NIGHTLY} --installed`.\n\
		Please install `rustup` to continue.",
			)
		});
	if !output.status.success() ||
		!output.stdout.split(|x| *x == b'\n').any(|x| x[..] == b"rust-src"[..])
	{
		if install_rustc {
			println!("Installing rustc dependencies...");
			let mut child = Command::new("rustup")
				.args(["toolchain", "install", NIGHTLY, "-c", "rust-src"])
				.stdout(std::process::Stdio::inherit())
				.stderr(std::process::Stdio::inherit())
				.spawn()
				.unwrap_or_else(|_| {
					panic!(
						"Failed to execute `rustup toolchain install {NIGHTLY} -c rust-src`.\n\
				Please install `rustup` to continue."
					)
				});
			if !child.wait().expect("Failed to execute rustup process").success() {
				panic!("Failed to install `rust-src` component of {}.", NIGHTLY);
			}
		} else {
			panic!("`rust-src` component of {} is required to build the PVM binary.", NIGHTLY);
		}
	}

	println!("Found good cargo environment. Building RISC-V ELF...");
	let mut child = Command::new("cargo")
		.current_dir(crate_dir)
		.env_clear()
		.env("PATH", std::env::var("PATH").unwrap())
		.env("RUSTFLAGS", "-C panic=abort")
		.env("CARGO_TARGET_DIR", out_dir)
		.arg(format!("+{}", NIGHTLY))
		.args(["build", "-Z", "build-std=core,alloc", "--release", "--target"])
		.arg(target_json_path)
		.stdout(std::process::Stdio::inherit())
		.stderr(std::process::Stdio::inherit())
		.spawn()
		.expect("Failed to execute cargo process");
	let status = child.wait().expect("Failed to execute cargo process");

	if !status.success() {
		eprintln!("Failed to build RISC-V ELF due to cargo execution error");
		std::process::exit(1);
	}

	let crate_name = get_crate_name(crate_dir);
	println!("Building PVM binary for: {}", crate_name);

	// Post processing
	println!("Converting RISC-V ELF to PVM blob...");
	let mut config = polkavm_linker::Config::default();
	config.set_strip(true);
	config.set_dispatch_table(blob_type.dispatch_table());
	let input_path = &out_dir.join(target_name).join("release").join(&crate_name);
	let orig =
		fs::read(input_path).unwrap_or_else(|e| panic!("Failed to read {:?} :{:?}", input_path, e));
	let linked = polkavm_linker::program_from_elf(config, orig.as_ref())
		.expect("Failed to link polkavm program:");

	// Write out a full `.polkavm` blob for debugging/inspection.
	let output_path_polkavm = &out_dir.join(format!("{}.polkavm", &crate_name));
	fs::write(output_path_polkavm, &linked).expect("Error writing resulting binary");

	let parts = polkavm_linker::ProgramParts::from_bytes(linked.into())
		.expect("failed to deserialize linked PolkaVM program");

	let mut ro_data = parts.ro_data.to_vec();
	ro_data.resize(parts.ro_data_size as usize, 0);

	let blob_jam = jam_types::ProgramBlob {
		ro_data: ro_data.into(),
		rw_data: (&parts.rw_data[..]).into(),
		code_blob: (&parts.code_and_jump_table[..]).into(),
		rw_data_padding: (parts.rw_data_size as usize - parts.rw_data.len()) as u32,
		stack_size: parts.stack_size,
	};

	let output_file = out_dir.join(format!("{}.jam", &crate_name));
	fs::write(&output_file, blob_jam.to_vec().expect("error serializing the .jam blob"))
		.expect("error writing the .jam blob");

	(crate_name, output_file)
}

#[macro_export]
macro_rules! pvm_binary {
	($name:literal) => {
		include_bytes!(concat!(env!("OUT_DIR"), "/", $name, ".jam"));
	};
}
jam_pvm_builder/lib.rs

jam_pvm_builder/
lib.rs
