build.rs

extern crate cc;
extern crate dunce;

use std::env;
use std::path::Path;

fn main() {
    let includepath = dunce::canonicalize(Path::new("include")).unwrap();
    println!("cargo:includepath={}", includepath.to_str().unwrap());

    let cfiledir = Path::new("cfiles");
    let common_files = vec![
        cfiledir.join("fips202.c"),
        cfiledir.join("aes.c"),
        cfiledir.join("sha2.c"),
        cfiledir.join("nistseedexpander.c"),
        cfiledir.join("sp800-185.c"),
    ];

    println!("cargo:rerun-if-changed=cfiles/");
    println!("cargo:rerun-if-changed=build.rs");
    println!("cargo:rerun-if-changed=src/");

    let mut build = cc::Build::new();

    let target_os = env::var("CARGO_CFG_TARGET_OS").unwrap();
    if target_os == "wasi" {
        let wasi_sdk_path =
            &std::env::var("WASI_SDK_DIR").expect("missing environment variable: WASI_SDK_DIR");
        build.flag(format!("--sysroot={wasi_sdk_path}").as_str());
    }

    build.include(&includepath);

    if let Some(libc) = std::env::var_os("DEP_WASM32_UNKNOWN_UNKNOWN_OPENBSD_LIBC_INCLUDE") {
        build.include(libc);
        println!("cargo::rustc-link-lib=wasm32-unknown-unknown-openbsd-libc");
    }

    build.files(common_files).compile("pqclean_common");
    println!("cargo:rustc-link-lib=pqclean_common");

    let target_arch = env::var("CARGO_CFG_TARGET_ARCH").unwrap_or_default();
    let target_env = env::var("CARGO_CFG_TARGET_ENV").unwrap_or_default();
    let mut builder = cc::Build::new();

    if target_os == "wasi" {
        let wasi_sdk_path =
            &std::env::var("WASI_SDK_DIR").expect("missing environment variable: WASI_SDK_DIR");
        builder.flag(format!("--sysroot={wasi_sdk_path}").as_str());
    }

    if target_arch == "x86" || target_arch == "x86_64" {
        if target_env == "msvc" {
            builder.flag("/arch:AVX2");
        } else {
            builder.flag("-mavx2");
        }
        builder
            .file(
                cfiledir
                    .join("keccak4x")
                    .join("KeccakP-1600-times4-SIMD256.c"),
            )
            .compile("keccak4x");
        println!("cargo:rustc-link-lib=keccak4x")
    } else if target_arch == "aarch64" && target_env != "msvc" {
        builder
            .flag("-march=armv8.2-a+sha3")
            .file(cfiledir.join("keccak2x").join("fips202x2.c"))
            .file(cfiledir.join("keccak2x").join("feat.S"))
            .compile("keccak2x");
        println!("cargo:rustc-link-lib=keccak2x")
    }
}