cel-cxx-ffi 0.1.0

FFI bindings for the cel-cxx crate
Documentation
use anyhow::Result;
use cel_build_utils::{Artifacts, Build};
use std::path::Path;

#[allow(unreachable_code)]
fn main() -> Result<()> {
    if skip_building() {
        return Ok(());
    }

    let artifacts = build_cpp()?;
    build_ffi(&artifacts)?;

    Ok(())
}

fn build_cpp() -> Result<Artifacts> {
    let artifacts = Build::new().build();
    artifacts.print_cargo_metadata();
    Ok(artifacts)
}

fn build_ffi(artifacts: &Artifacts) -> Result<()> {
    let hh_pattern = "include/**/*.h";
    let _hdrs = glob::glob(hh_pattern)?
        .collect::<Result<Vec<_>, _>>()?
        .into_iter()
        .inspect(|path| {
            println!("cargo:rerun-if-changed={}", path.display());
        })
        .collect::<Vec<_>>();

    let cc_pattern = "src/**/*.cc";
    let cc_srcs = glob::glob(cc_pattern)?
        .collect::<Result<Vec<_>, _>>()?
        .into_iter()
        .inspect(|path| {
            println!("cargo:rerun-if-changed={}", path.display());
        })
        .collect::<Vec<_>>();

    let rs_excludes = ["src/lib.rs", "src/common/mod.rs"]
        .into_iter()
        .map(Path::new)
        .collect::<Vec<_>>();

    let rs_pattern = "src/**/*.rs";
    let rs_srcs = glob::glob(rs_pattern)?
        .collect::<Result<Vec<_>, _>>()?
        .into_iter()
        .inspect(|path| {
            println!("cargo:rerun-if-changed={}", path.display());
        })
        .filter(|path| !rs_excludes.contains(&path.as_path()))
        .collect::<Vec<_>>();

    cxx_build::bridges(rs_srcs)
        .include(artifacts.include_dir())
        .flag("-Wno-missing-requires")
        .flag("-Wno-deprecated-declarations")
        .flag("-Wno-unused-parameter")
        .flag("-Wno-class-memaccess")
        .flag("-Wno-return-type")
        .flag("-Wno-sign-compare")
        .files(cc_srcs)
        .std("c++17")
        .compile("cel-cxx");

    println!("cargo:rustc-link-lib=static=cel-cxx");
    Ok(())
}

/// Check if we're building for documentation or analysis tools
fn skip_building() -> bool {
    // Check for docs.rs environment
    if std::env::var("DOCS_RS").is_ok() {
        println!("cargo:warning=Skipping C++ build for docs.rs");
        return true;
    }

    // Check for CEL_CXX_FFI_SKIP_BUILD environment variable
    // This is useful when c++ build is not necessary, e.g. when used with cargo check
    //
    // example:
    // CEL_CXX_FFI_SKIP_BUILD=1 cargo check
    if std::env::var("CEL_CXX_FFI_SKIP_BUILD").is_ok() {
        println!("cargo:warning=Skipping C++ build due to CEL_CXX_FFI_SKIP_BUILD");
        return true;
    }

    // Check for analysis tools environment variables
    if is_analysis_tools() {
        println!("cargo:warning=Skipping C++ build for analysis tools");
        return true;
    }

    false
}

/// Detect if the build is being triggered by rust-analyzer / clippy
fn is_analysis_tools() -> bool {
    // Check for rust-analyzer specific environment variables
    if std::env::var("RA_RUSTC_WRAPPER").is_ok() {
        return true;
    }

    // Check if RUSTC_WRAPPER contains rust-analyzer
    if let Ok(wrapper) = std::env::var("RUSTC_WRAPPER") {
        if wrapper.contains("rust-analyzer") {
            return true;
        }
        if wrapper.contains("clippy") {
            return true;
        }
    }

    if let Ok(wrapper) = std::env::var("RUSTC_WORKSPACE_WRAPPER") {
        if wrapper.contains("rust-analyzer") {
            return true;
        }
        if wrapper.contains("clippy") {
            return true;
        }
    }

    false
}