build.rs

extern crate cbindgen;

use std::env;
use std::path::PathBuf;
use cbindgen::{Config, Language};


fn main() {
  let crate_dir = env::var("CARGO_MANIFEST_DIR").unwrap();

  let package_name = env::var("CARGO_PKG_NAME").unwrap();
  let output_file = target_dir()
      .join(format!("{}.h", package_name))
      .display()
      .to_string();

  let config = Config {
      include_guard: Some("TCMB_EVDS_C_H".to_string()),
      line_length: 120,
      language: Language::C,
      ..Default::default()
  };
                                                                                                                      
  cbindgen::generate_with_config(&crate_dir, config)
    .unwrap()
    .write_to_file(&output_file);
}


/// Find the location of the `target/` directory. Note that this may be 
/// overridden by `cmake`, so we also need to check the `CARGO_TARGET_DIR` 
/// variable.
fn target_dir() -> PathBuf {
  if let Ok(target) = env::var("CARGO_TARGET_DIR") {
      PathBuf::from(target)
  }
  else {
      PathBuf::from(env::var("CARGO_MANIFEST_DIR").unwrap()).join("target")
  }
}