build.rs

extern crate chrono;
extern crate git2;

use std::env;
use std::fs::File;
use std::io::Write;
use std::process::Command;
use std::path::{Path, PathBuf};

fn main() {
    // build info
    let out_dir = PathBuf::from(env::var_os("OUT_DIR").unwrap());
    let mut f = File::create(&out_dir.join("build-info.txt")).unwrap();

    if let Ok(commit) = read_commit() {
        writeln!(f, "commit: {}", commit).unwrap();
    }
    writeln!(f, "build date: {}", chrono::Utc::today()).unwrap();

    // windres icon
    if cfg!(windows) {
        let out_dir = env::var("OUT_DIR").ok().expect("can't find out_dir");

        if cfg!(target_env="msvc") {
            if let Err(e) = Command::new("windres")
                .args(&["res/editor.rc", "-o"])
                .arg(&format!("{}/editor_rc.lib", out_dir))
                .status()
            {
                println!("cargo:warning=`windres` unavailable: {}", e);
                return;
            }
        } else {
            if let Err(e) = Command::new("windres")
                .args(&["res/editor.rc", "-o"])
                .arg(&format!("{}/editor.rc.o", out_dir))
                .status()
            {
                println!("cargo:warning=`windres` unavailable: {}", e);
                return;
            }
            Command::new("ar")
                .args(&["crus", "libeditor_rc.a", "editor.rc.o"])
                .current_dir(Path::new(&out_dir))
                .status()
                .unwrap();
        }

        println!("cargo:rerun-if-changed=editor.rc");
        println!("cargo:rerun-if-changed=gasmask.ico");
        println!("cargo:rustc-link-search=native={}", out_dir);
        println!("cargo:rustc-link-lib=static=editor_rc");
    }
}

fn read_commit() -> Result<String, git2::Error> {
    let repo = git2::Repository::discover(".")?;
    let hash = repo.head()?.peel_to_commit()?.id().to_string();
    Ok(hash)
}