Include git commit hash in version output

To better identify issues or just get an idea which change exactly a
given binary was built from, this patch makes sure to contain the Git
commit hash (or tag, if present) in the version output we provide via
the -V/--version flag.

Cargo.toml

@@ -28,6 +28,9 @@ path = "var/shell-complete.rs"
 name = "nitrocli-otp-cache"
 path = "ext/otp_cache.rs"
 
+[build-dependencies]
+anyhow = "1.0"
+
 [profile.release]
 opt-level = "z"
 lto = true

build.rs

@@ -0,0 +1,115 @@
+// Copyright (C) 2021-2022 The Nitrocli Developers
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+use std::process::Command;
+
+use anyhow::bail;
+use anyhow::Context;
+use anyhow::Result;
+
+const GIT: &str = "git";
+
+/// Format a git command with the given list of arguments as a string.
+fn git_command(args: &[&str]) -> String {
+ args.iter().fold(GIT.to_string(), |mut cmd, arg| {
+ cmd += " ";
+ cmd += arg;
+ cmd
+ })
+}
+
+/// Run git with the provided arguments and read the output it emits.
+fn git_output(args: &[&str]) -> Result<String> {
+ let git = Command::new(GIT)
+ .args(args)
+ .output()
+ .with_context(|| format!("failed to run `{}`", git_command(args)))?;
+
+ if !git.status.success() {
+ let code = if let Some(code) = git.status.code() {
+ format!(" ({})", code)
+ } else {
+ String::new()
+ };
+
+ bail!(
+ "`{}` reported non-zero exit-status{}",
+ git_command(args),
+ code
+ );
+ }
+
+ let output = String::from_utf8(git.stdout).with_context(|| {
+ format!(
+ "failed to read `{}` output as UTF-8 string",
+ git_command(args)
+ )
+ })?;
+
+ Ok(output)
+}
+
+/// Run git with the provided arguments and report the status of the
+/// command.
+fn git_run(args: &[&str]) -> Result<bool> {
+ Command::new(GIT)
+ .args(args)
+ .status()
+ .with_context(|| format!("failed to run `{}`", git_command(args)))
+ .map(|status| status.success())
+}
+
+/// Retrieve a git revision identifier that either includes the tag we
+/// are on or the shortened SHA-1. It also contains an indication
+/// whether local changes were present.
+fn git_revision() -> Result<Option<String>> {
+ // As a first step we check whether we are in a git repository and
+ // whether git is working to begin with. If not, we can't do much; yet
+ // we still want to allow the build to continue, so we merely print a
+ // warning and continue without a git revision. But once these checks
+ // are through, we treat subsequent failures as unexpected and fatal.
+ match git_run(&["rev-parse", "--git-dir"]) {
+ Ok(true) => (),
+ Ok(false) => {
+ println!("cargo:warning=Not in a git repository; unable to embed git revision");
+ return Ok(None);
+ }
+ Err(err) => {
+ println!(
+ "cargo:warning=Failed to invoke `git`; unable to embed git revision: {}",
+ err
+ );
+ return Ok(None);
+ }
+ }
+
+ let local_changes = git_output(&["status", "--porcelain", "--untracked-files=no"])?;
+ let modified = !local_changes.is_empty();
+
+ // If we are on a tag then just include the tag name. Otherwise use
+ // the shortened SHA-1.
+ let revision = if let Ok(tag) = git_output(&["describe", "--exact-match", "--tags", "HEAD"]) {
+ tag
+ } else {
+ git_output(&["rev-parse", "--short", "HEAD"])?
+ };
+ let revision = format!("{}{}", revision.trim(), if modified { "+" } else { "" });
+ Ok(Some(revision))
+}
+
+fn main() -> Result<()> {
+ if let Some(git_revision) = git_revision()? {
+ println!("cargo:rustc-env=NITROCLI_GIT_REVISION={}", git_revision);
+ }
+ // Make sure to run this script again if any of our sources files or
+ // any relevant version control files changes (e.g., when creating a
+ // commit or a tag).
+ println!("cargo:rerun-if-changed=.git/index");
+ println!("cargo:rerun-if-changed=.git/refs/");
+ println!("cargo:rerun-if-changed=Cargo.lock");
+ println!("cargo:rerun-if-changed=Cargo.toml");
+ println!("cargo:rerun-if-changed=ext/");
+ println!("cargo:rerun-if-changed=src/");
+ println!("cargo:rerun-if-changed=var/");
+ Ok(())
+}

src/main.rs

@@ -1,6 +1,6 @@
 // main.rs
 
-// Copyright (C) 2017-2021 The Nitrocli Developers
+// Copyright (C) 2017-2022 The Nitrocli Developers
 // SPDX-License-Identifier: GPL-3.0-or-later
 
 #![warn(
@@ -163,11 +163,18 @@ fn handle_arguments(ctx: &mut Context<'_>, argv: Vec<String>) -> anyhow::Result<
 
 fn get_version_string() -> String {
  let version = env!("CARGO_PKG_VERSION");
- if let Ok(library_version) = nitrokey::get_library_version() {
- format!("{} using libnitrokey {}", version, library_version)
+ let built_from = if let Some(git_revision) = option_env!("NITROCLI_GIT_REVISION") {
+ format!(" (built from {})", git_revision)
  } else {
- format!("{} using an undetectable libnitrokey version", version)
- }
+ "".to_string()
+ };
+ let libnitrokey = if let Ok(library_version) = nitrokey::get_library_version() {
+ format!("libnitrokey {}", library_version)
+ } else {
+ "an undetectable libnitrokey version".to_string()
+ };
+
+ format!("{}{} using {}", version, built_from, libnitrokey)
 }
 
 /// The context used when running the program.