Initial commit

build.rs

@@ -0,0 +1,35 @@
+use std::{env, fs, path::Path, process::Command};
+
+fn command_output(command: &str, args: &[&str]) -> String {
+    Command::new(command)
+        .args(args)
+        .output()
+        .ok()
+        .filter(|output| output.status.success())
+        .map(|output| String::from_utf8_lossy(&output.stdout).trim().to_owned())
+        .filter(|output| !output.is_empty())
+        .unwrap_or_else(|| "unknown".to_owned())
+}
+
+fn main() {
+    let out_dir = env::var_os("OUT_DIR").expect("OUT_DIR is set by Cargo");
+    let version = env::var("CARGO_PKG_VERSION").unwrap_or_else(|_| "unknown".to_owned());
+    let rustc = env::var("RUSTC").unwrap_or_else(|_| "rustc".to_owned());
+    let rustc_version = command_output(&rustc, &["--version"]);
+    let target = env::var("TARGET").unwrap_or_else(|_| "unknown".to_owned());
+
+    println!("cargo:rustc-env=TG_BOT_RUSTC_VERSION={rustc_version}");
+    println!("cargo:rustc-env=TG_BOT_TARGET={target}");
+
+    let version_text = format!(
+        "{}\nbuild-time: {}\ncommit: {}\ntarget: {}\nrustc: {}",
+        version,
+        command_output("date", &["-u", "+%Y-%m-%d %H:%M:%S UTC"]),
+        command_output("git", &["rev-parse", "--short", "HEAD"]),
+        target,
+        rustc_version,
+    );
+
+    fs::write(Path::new(&out_dir).join("version.txt"), version_text)
+        .expect("failed to write generated version information");
+}