build.rs

// Copyright 2018-2021 Parity Technologies (UK) Ltd.
// This file is part of cargo-contract.
//
// cargo-contract is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// cargo-contract is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with cargo-contract.  If not, see <http://www.gnu.org/licenses/>.

use crate::{
    crate_metadata::CrateMetadata,
    maybe_println, util, validate_wasm,
    workspace::{Manifest, ManifestPath, Profile, Workspace},
    BuildArtifacts, BuildMode, BuildResult, OptimizationPasses, OptimizationResult, UnstableFlags,
    UnstableOptions, Verbosity, VerbosityFlags,
};
use anyhow::{Context, Result};
use colored::Colorize;
use parity_wasm::elements::{External, Internal, MemoryType, Module, Section};
use regex::Regex;
use semver::Version;
use std::{
    convert::TryFrom,
    ffi::OsStr,
    fs::metadata,
    path::{Path, PathBuf},
    process::Command,
    str,
};
use structopt::StructOpt;

/// This is the maximum number of pages available for a contract to allocate.
const MAX_MEMORY_PAGES: u32 = 16;

/// Executes build of the smart-contract which produces a wasm binary that is ready for deploying.
///
/// It does so by invoking `cargo build` and then post processing the final binary.
#[derive(Debug, StructOpt)]
#[structopt(name = "build")]
pub struct BuildCommand {
    /// Path to the Cargo.toml of the contract to build
    #[structopt(long, parse(from_os_str))]
    manifest_path: Option<PathBuf>,
    /// By default the contract is compiled with debug functionality
    /// included. This enables the contract to output debug messages,
    /// but increases the contract size and the amount of gas used.
    ///
    /// A production contract should always be build in `release` mode!
    /// Then no debug functionality is compiled into the contract.
    #[structopt(long = "--release")]
    build_release: bool,
    /// Which build artifacts to generate.
    ///
    /// - `all`: Generate the Wasm, the metadata and a bundled `<name>.contract` file.
    ///
    /// - `code-only`: Only the Wasm is created, generation of metadata and a bundled
    ///   `<name>.contract` file is skipped.
    #[structopt(
        long = "generate",
        default_value = "all",
        value_name = "all | code-only",
        verbatim_doc_comment
    )]
    build_artifact: BuildArtifacts,
    #[structopt(flatten)]
    verbosity: VerbosityFlags,
    #[structopt(flatten)]
    unstable_options: UnstableOptions,
    /// Number of optimization passes, passed as an argument to wasm-opt.
    ///
    /// - `0`: execute no optimization passes
    ///
    /// - `1`: execute 1 optimization pass (quick & useful opts, useful for iteration builds)
    ///
    /// - `2`, execute 2 optimization passes (most opts, generally gets most perf)
    ///
    /// - `3`, execute 3 optimization passes (spends potentially a lot of time optimizing)
    ///
    /// - `4`, execute 4 optimization passes (also flatten the IR, which can take a lot more time and memory
    /// but is useful on more nested / complex / less-optimized input)
    ///
    /// - `s`, execute default optimization passes, focusing on code size
    ///
    /// - `z`, execute default optimization passes, super-focusing on code size
    ///
    /// - The default value is `z`
    ///
    /// - It is possible to define the number of optimization passes in the
    ///   `[package.metadata.contract]` of your `Cargo.toml` as e.g. `optimization-passes = "3"`.
    ///   The CLI argument always takes precedence over the profile value.
    #[structopt(long)]
    optimization_passes: Option<OptimizationPasses>,
    /// Do not remove symbols (Wasm name section) when optimizing.
    ///
    /// This is useful if one wants to analyze or debug the optimized binary.
    #[structopt(long)]
    keep_debug_symbols: bool,
}

impl BuildCommand {
    pub fn exec(&self) -> Result<BuildResult> {
        let manifest_path = ManifestPath::try_from(self.manifest_path.as_ref())?;
        let unstable_flags: UnstableFlags =
            TryFrom::<&UnstableOptions>::try_from(&self.unstable_options)?;
        let verbosity = TryFrom::<&VerbosityFlags>::try_from(&self.verbosity)?;

        // The CLI flag `optimization-passes` overwrites optimization passes which are
        // potentially defined in the `Cargo.toml` profile.
        let optimization_passes = match self.optimization_passes {
            Some(opt_passes) => opt_passes,
            None => {
                let mut manifest = Manifest::new(manifest_path.clone())?;
                match manifest.get_profile_optimization_passes() {
                    // if no setting is found, neither on the cli nor in the profile,
                    // then we use the default
                    None => OptimizationPasses::default(),
                    Some(opt_passes) => opt_passes,
                }
            }
        };

        let build_mode = match self.build_release {
            true => BuildMode::Release,
            false => BuildMode::Debug,
        };
        execute(
            &manifest_path,
            verbosity,
            build_mode,
            self.build_artifact,
            unstable_flags,
            optimization_passes,
            self.keep_debug_symbols,
        )
    }
}

#[derive(Debug, StructOpt)]
#[structopt(name = "check")]
pub struct CheckCommand {
    /// Path to the Cargo.toml of the contract to build
    #[structopt(long, parse(from_os_str))]
    manifest_path: Option<PathBuf>,
    #[structopt(flatten)]
    verbosity: VerbosityFlags,
    #[structopt(flatten)]
    unstable_options: UnstableOptions,
}

impl CheckCommand {
    pub fn exec(&self) -> Result<BuildResult> {
        let manifest_path = ManifestPath::try_from(self.manifest_path.as_ref())?;
        let unstable_flags: UnstableFlags =
            TryFrom::<&UnstableOptions>::try_from(&self.unstable_options)?;
        let verbosity: Verbosity = TryFrom::<&VerbosityFlags>::try_from(&self.verbosity)?;
        execute(
            &manifest_path,
            verbosity,
            BuildMode::Debug,
            BuildArtifacts::CheckOnly,
            unstable_flags,
            OptimizationPasses::Zero,
            false,
        )
    }
}

/// Executes the supplied cargo command on the project in the specified directory, defaults to the
/// current directory.
///
/// Uses the unstable cargo feature [`build-std`](https://doc.rust-lang.org/nightly/cargo/reference/unstable.html#build-std)
/// to build the standard library with [`panic_immediate_abort`](https://github.com/johnthagen/min-sized-rust#remove-panic-string-formatting-with-panic_immediate_abort)
/// which reduces the size of the Wasm binary by not including panic strings and formatting code.
///
/// # Cargo.toml optimizations
///
/// The original Cargo.toml will be amended to remove the `rlib` crate type in order to minimize
/// the final Wasm binary size.
///
/// Preferred default `[profile.release]` settings will be added if they are missing, existing
/// user-defined settings will be preserved.
///
/// To disable this and use the original `Cargo.toml` as is then pass the `-Z original_manifest` flag.
fn exec_cargo_for_wasm_target(
    crate_metadata: &CrateMetadata,
    command: &str,
    build_mode: BuildMode,
    verbosity: Verbosity,
    unstable_flags: &UnstableFlags,
) -> Result<()> {
    util::assert_channel()?;

    // set linker args via RUSTFLAGS.