build.rs

//! This build script copies the `memory.x` file from the crate root into
//! a directory where the linker can always find it at build time.
//! For many projects this is optional, as the linker always searches the
//! project root directory -- wherever `Cargo.toml` is. However, if you
//! are using a workspace or have a more complicated build setup, this
//! build script becomes required. Additionally, by requesting that
//! Cargo re-run the build script whenever `memory.x` is changed,
//! updating `memory.x` ensures a rebuild of the application with the
//! new memory settings.

use std::env;
use std::fs::File;
use std::io::Write;
use std::path::PathBuf;

fn main() {
    // Put `memory.x` in our output directory and ensure it's
    // on the linker search path.
    let out = &PathBuf::from(env::var_os("OUT_DIR").unwrap());

    let memory_x = if env::var("CARGO_FEATURE_PICO2W").is_ok() {
        include_str!("pico2w.x")
    } else if env::var("CARGO_FEATURE_PIMORONI2W").is_ok() {
        include_str!("pimoroni2w.x")
    } else {
        include_str!("memory.x")
    };

    File::create(out.join("memory.x"))
        .unwrap()
        .write_all(memory_x.as_bytes())
        .unwrap();
    println!("cargo:rustc-link-search={}", out.display());

    // By default, Cargo will re-run a build script whenever
    // any file in the project changes. By specifying `memory.x`
    // here, we ensure the build script is only re-run when
    // `memory.x` is changed.
    println!("cargo:rerun-if-changed=memory.x");

    println!("cargo:rustc-link-arg-bins=--nmagic");
    println!("cargo:rustc-link-arg-bins=-Tlink.x");

    let mut ci_tag = "unknown".to_string();

    if let Ok(output) = std::process::Command::new("git")
        .args(&[
            "-c",
            "core.abbrev=8",
            "show",
            "-s",
            "--format=%cd-%h",
            "--date=format:%Y%m%d",
        ])
        .output()
    {
        let info = String::from_utf8_lossy(&output.stdout);
        ci_tag = info.trim().to_string();
    }

    println!("cargo:rustc-env=WEZTERM_CI_TAG={}", ci_tag);
}