extern crate env_logger; #[macro_use] extern crate failure; extern crate wasm_bindgen_webidl; extern crate sourcefile; use failure::{Fail, ResultExt}; use sourcefile::SourceFile; use std::collections::HashSet; use std::env; use std::ffi::OsStr; use std::fs; use std::path::{self, PathBuf}; use std::process::{self, Command}; fn main() { env_logger::init(); if let Err(e) = try_main() { eprintln!("Error: {}", e); for c in e.iter_causes() { eprintln!(" caused by {}", c); } process::exit(1); } } fn try_main() -> Result<(), failure::Error> { println!("cargo:rerun-if-changed=build.rs"); println!("cargo:rerun-if-changed=webidls/enabled"); let entries = fs::read_dir("webidls/enabled").context("reading webidls/enabled directory")?; let mut source = SourceFile::default(); for entry in entries { let entry = entry.context("getting webidls/enabled/*.webidl entry")?; let path = entry.path(); if path.extension() != Some(OsStr::new("webidl")) { continue } println!("cargo:rerun-if-changed={}", path.display()); source = source.add_file(&path) .with_context(|_| format!("reading contents of file \"{}\"", path.display()))?; } // Read our manifest, learn all `[feature]` directives with "toml parsing". // Use all these names to match against environment variables set by Cargo // to figure out which features are activated to we can pass that down to // the webidl compiler. let manifest_dir = PathBuf::from(env::var_os("CARGO_MANIFEST_DIR").unwrap()); let manifest = fs::read_to_string(manifest_dir.join("Cargo.toml"))?; let features = manifest.lines().skip_while(|f| !f.starts_with("[features]")); let enabled_features = env::vars() .map(|p| p.0) .filter(|p| p.starts_with("CARGO_FEATURE_")) .map(|mut p| { p.drain(0.."CARGO_FEATURE_".len()); p }) .collect::>(); let mut allowed = Vec::new(); for feature in features.filter(|f| !f.starts_with("#") && !f.starts_with("[")) { let mut parts = feature.split('='); let name = parts.next().unwrap().trim(); if enabled_features.contains(&name.to_uppercase()) { allowed.push(name); } } // If we're printing all features don't filter anything let allowed = if env::var("__WASM_BINDGEN_DUMP_FEATURES").is_ok() { None } else { Some(&allowed[..]) }; let bindings = match wasm_bindgen_webidl::compile(&source.contents, allowed) { Ok(bindings) => bindings, Err(e) => match e.kind() { wasm_bindgen_webidl::ErrorKind::ParsingWebIDLSourcePos(pos) => { if let Some(pos) = source.resolve_offset(pos) { let ctx = format!("compiling WebIDL into wasm-bindgen bindings in file \ \"{}\", line {} column {}", pos.filename, pos.line + 1, pos.col + 1); return Err(e.context(ctx).into()); } else { return Err(e.context("compiling WebIDL into wasm-bindgen bindings").into()); } } _ => { return Err(e.context("compiling WebIDL into wasm-bindgen bindings").into()); } } }; let out_dir = env::var("OUT_DIR").context("reading OUT_DIR environment variable")?; let out_file_path = path::Path::new(&out_dir).join("bindings.rs"); fs::write(&out_file_path, bindings) .context("writing bindings to output file")?; // run rustfmt on the generated file - really handy for debugging println!("cargo:rerun-if-env-changed=WEBIDL_RUSTFMT_BINDINGS"); if env::var("WEBIDL_RUSTFMT_BINDINGS").is_ok() { let status = Command::new("rustfmt") .arg(&out_file_path) .status() .context("running rustfmt")?; if !status.success() { bail!("rustfmt failed: {}", status) } } Ok(()) }