save session metadata

codex-rs/session/build.rs

@@ -0,0 +1,19 @@
+// build.rs – emit the current git commit so the code can embed it in the
+// session metadata file.
+
+fn main() {
+    // Try to run `git rev-parse HEAD` – if that fails we fall back to
+    // "unknown" so the build does not break when the source is not a git
+    // repository (e.g., during `cargo publish`).
+    let git_sha = std::process::Command::new("git")
+        .args(["rev-parse", "HEAD"])
+        .output()
+        .ok()
+        .filter(|o| o.status.success())
+        .and_then(|o| String::from_utf8(o.stdout).ok())
+        .map(|s| s.trim().to_owned())
+        .unwrap_or_else(|| "unknown".into());
+
+    println!("cargo:rustc-env=GIT_SHA={git_sha}");
+}
+