electrs/build.rs
2023-07-23 01:45:10 -07:00

57 lines
1.9 KiB
Rust

use std::{path::Path, process::Command};
fn main() {
// Specify re-run conditions
// 1. Rerun build script if we pass a new GIT_HASH
println!("cargo:rerun-if-env-changed=GIT_HASH");
// 2. Only do git based reruns if git directory exists
if Path::new(".git").exists() {
// If we change the branch, rerun
println!("cargo:rerun-if-changed=.git/HEAD");
if let Ok(r) = std::fs::read_to_string(".git/HEAD") {
if let Some(stripped) = r.strip_prefix("ref: ") {
// If the HEAD is detached it will be a commit hash
// so the HEAD changed directive above will pick it up,
// otherwise it will point to a ref in the refs directory
println!("cargo:rerun-if-changed=.git/{}", stripped);
}
}
}
// Getting git hash
// Don't fetch git hash if it's already in the ENV
let existing = std::env::var("GIT_HASH").unwrap_or_else(|_| String::new());
if !existing.is_empty() {
return;
}
// Get git hash from git and don't do anything if the command fails
if let Some(rev_parse) = cmd("git", &["rev-parse", "--short", "HEAD"]) {
// Add (dirty) to the GIT_HASH if the git status isn't clean
// This includes untracked files
let dirty = cmd("git", &["status", "--short"]).expect("git command works");
let git_hash = if dirty.is_empty() {
rev_parse
} else {
format!("{}(dirty)", rev_parse.trim())
};
println!("cargo:rustc-env=GIT_HASH={}", git_hash.trim());
}
}
// Helper function, Command is verbose...
fn cmd(name: &str, args: &[&str]) -> Option<String> {
Command::new(name).args(args).output().ok().and_then(|o| {
if o.status.success() {
String::from_utf8(o.stdout).ok()
} else {
None
}
})
}