feat: add a linkage checker subcommand

cargo-dist/src/cli.rs

@@ -127,6 +127,9 @@ pub enum Commands {
     /// Generate CI scripts for orchestrating cargo-dist (deprecated in favour of generate)
     #[clap(disable_version_flag = true)]
     GenerateCi(GenerateCiArgs),
+    /// Report on the dynamic libraries used by the built artifacts.
+    #[clap(disable_version_flag = true)]
+    Linkage(LinkageArgs),
     /// Generate the final build manifest without running any builds.
     ///
     /// This command is designed to match the exact behaviour of
@@ -277,6 +280,17 @@ pub struct GenerateCiArgs {
     #[clap(default_value_t = false)]
     pub check: bool,
 }
+#[derive(Args, Clone, Debug)]
+pub struct LinkageArgs {
+    /// Print human-readable output
+    #[clap(long)]
+    #[clap(default_value_t = false)]
+    pub print_output: bool,
+    /// Print output as JSON
+    #[clap(long)]
+    #[clap(default_value_t = false)]
+    pub print_json: bool,
+}
 
 #[derive(Args, Clone, Debug)]
 pub struct HelpMarkdownArgs {}

cargo-dist/src/errors.rs

@@ -229,6 +229,14 @@ pub enum DistError {
         /// The missing keys
         keys: &'static [&'static str],
     },
+    /// Linkage check can't be run for this combination of OS and target
+    #[error("unable to run linkage check for {target} on {host}")]
+    LinkageCheckInvalidOS {
+        /// The OS the check was run on
+        host: String,
+        /// The OS being checked
+        target: String,
+    },
 }
 
 impl From<minijinja::Error> for DistError {

cargo-dist/src/lib.rs

@@ -27,6 +27,7 @@ use config::{
     ArtifactMode, ChecksumStyle, CompressionImpl, Config, DirtyMode, GenerateMode, ZipStyle,
 };
 use semver::Version;
+use serde::Serialize;
 use tracing::{info, warn};
 
 use errors::*;
@@ -617,6 +618,15 @@ pub struct GenerateArgs {
     pub modes: Vec<GenerateMode>,
 }
 
+/// Arguments for `cargo dist linkage` ([`do_linkage][])
+#[derive(Debug)]
+pub struct LinkageArgs {
+    /// Print human-readable output
+    pub print_output: bool,
+    /// Print output as JSON
+    pub print_json: bool,
+}
+
 fn do_generate_preflight_checks(dist: &DistGraph) -> Result<()> {
     // Enforce cargo-dist-version, unless...
     //
@@ -709,6 +719,165 @@ pub fn run_generate(dist: &DistGraph, args: &GenerateArgs) -> Result<()> {
     Ok(())
 }
 
+/// Determinage dynamic linkage of built artifacts (impl of `cargo dist linkage`)
+pub fn do_linkage(cfg: &Config, args: &LinkageArgs) -> Result<()> {
+    let dist = gather_work(cfg)?;
+
+    let mut reports = vec![];
+
+    for target in cfg.targets.clone() {
+        let releases: Vec<Release> = dist
+            .releases
+            .clone()
+            .into_iter()
+            .filter(|r| r.targets.contains(&target))
+            .collect();
+
+        if releases.is_empty() {
+            eprintln!("No matching release for target {target}");
+            continue;
+        }
+
+        for release in releases {
+            let path = Utf8PathBuf::from(&dist.dist_dir).join(format!("{}-{target}", release.id));
+
+            for (_, binary) in release.bins {
+                let bin_path = path.join(binary);
+                if !bin_path.exists() {
+                    eprintln!("Binary {bin_path} missing; skipping check");
+                } else {
+                    reports.push(determine_linkage(&bin_path, &target)?);
+                }
+            }
+        }
+    }
+
+    if args.print_output {
+        for report in &reports {
+            eprintln!("{}", report.report());
+        }
+    }
+    if args.print_json {
+        let j = serde_json::to_string(&reports).unwrap();
+        println!("{}", j);
+    }
+
+    Ok(())
+}
+
+/// Information about dynamic libraries used by a binary
+#[derive(Debug, Serialize)]
+pub struct Linkage {
+    /// The filename of the binary
+    pub binary: String,
+    /// The target triple for which the binary was built
+    pub target: String,
+    /// Libraries included with the operating system
+    pub system: Vec<String>,
+    /// Libraries provided by the Homebrew package manager
+    pub homebrew: Vec<String>,
+    /// Public libraries not provided by the system and not managed by any package manager
+    pub public_unmanaged: Vec<String>,
+    /// Libraries which don't fall into any other categories
+    pub other: Vec<String>,
+    /// Frameworks, only used on macOS
+    pub frameworks: Vec<String>,
+}
+
+impl Linkage {
+    /// Formatted human-readable output
+    pub fn report(&self) -> String {
+        let s = format!(
+            r#"{} ({}):
+
+System: {}
+Homebrew: {}
+Public (unmanaged): {}
+Frameworks: {}
+Other: {}"#,
+            self.binary,
+            self.target,
+            self.system.join(" "),
+            self.homebrew.join(" "),
+            self.public_unmanaged.join(" "),
+            self.frameworks.join(" "),
+            self.other.join(" "),
+        );
+
+        s.to_owned()
+    }
+}
+
+fn do_otool(path: &Utf8PathBuf) -> DistResult<Vec<String>> {
+    let output = Command::new("otool")
+        .arg("-XL")
+        .arg(path)
+        .output()
+        .expect("otool failed to run");
+
+    let mut result = String::from_utf8_lossy(&output.stdout).to_string();
+    if let Some(stripped) = result.strip_suffix('\n') {
+        result = stripped.to_owned();
+    }
+    let libraries: Vec<String> = result
+        .split('\n')
+        // Lines are formatted like:
+        // "/usr/lib/libiconv.2.dylib (compatibility version 7.0.0, current version 7.0.0)"
+        .map(|line| {
+            line.trim_start()
+                .split('(')
+                .next()
+                .unwrap()
+                .trim_end()
+                .to_string()
+        })
+        .collect();
+
+    Ok(libraries)
+}
+
+fn determine_linkage(path: &Utf8PathBuf, target: &str) -> DistResult<Linkage> {
+    // Update this as more OSs are supported
+    if std::env::consts::OS != "macos" {
+        return Err(DistError::LinkageCheckInvalidOS {
+            host: std::env::consts::OS.to_owned(),
+            target: target.to_owned(),
+        });
+    }
+
+    let libraries = do_otool(path)?;
+    let mut linkage = Linkage {
+        binary: path.file_name().unwrap().to_owned(),
+        target: target.to_owned(),
+        system: vec![],
+        homebrew: vec![],
+        public_unmanaged: vec![],
+        frameworks: vec![],
+        other: vec![],
+    };
+    for library in libraries {
+        if library.starts_with("/opt/homebrew") {
+            linkage.homebrew.push(library.clone());
+        } else if library.starts_with("/usr/lib") || library.starts_with("/lib") {
+            linkage.system.push(library.clone());
+        } else if library.starts_with("/System/Library/Frameworks")
+            || library.starts_with("/Library/Frameworks")
+        {
+            linkage.frameworks.push(library.clone());
+        } else if library.starts_with("/usr/local") {
+            if std::fs::canonicalize(&library)?.starts_with("/usr/local/Cellar") {
+                linkage.homebrew.push(library.clone());
+            } else {
+                linkage.public_unmanaged.push(library.clone());
+            }
+        } else {
+            linkage.other.push(library.clone());
+        }
+    }
+
+    Ok(linkage)
+}
+
 /// Run any necessary integrity checks for "primary" commands like build/plan
 ///
 /// (This is currently equivalent to `cargo dist generate --check`)

cargo-dist/src/main.rs

@@ -15,7 +15,7 @@ use cli::{
 use console::Term;
 use miette::IntoDiagnostic;
 
-use crate::cli::{BuildArgs, GenerateArgs, GenerateCiArgs, InitArgs};
+use crate::cli::{BuildArgs, GenerateArgs, GenerateCiArgs, InitArgs, LinkageArgs};
 
 mod cli;
 
@@ -33,6 +33,7 @@ fn real_main(cli: &axocli::CliApp<Cli>) -> Result<(), miette::Report> {
         Commands::Init(args) => cmd_init(config, args),
         Commands::Generate(args) => cmd_generate(config, args),
         Commands::GenerateCi(args) => cmd_generate_ci(config, args),
+        Commands::Linkage(args) => cmd_linkage(config, args),
         Commands::Manifest(args) => cmd_manifest(config, args),
         Commands::Plan(args) => cmd_plan(config, args),
         Commands::HelpMarkdown(args) => cmd_help_md(config, args),
@@ -244,6 +245,27 @@ fn cmd_generate(cli: &Cli, args: &GenerateArgs) -> Result<(), miette::Report> {
     do_generate(&config, &args)
 }
 
+fn cmd_linkage(cli: &Cli, args: &LinkageArgs) -> Result<(), miette::Report> {
+    let config = cargo_dist::config::Config {
+        needs_coherent_announcement_tag: false,
+        artifact_mode: cargo_dist::config::ArtifactMode::All,
+        no_local_paths: cli.no_local_paths,
+        allow_all_dirty: cli.allow_dirty,
+        targets: cli.target.clone(),
+        ci: cli.ci.iter().map(|ci| ci.to_lib()).collect(),
+        installers: cli.installer.iter().map(|ins| ins.to_lib()).collect(),
+        announcement_tag: cli.tag.clone(),
+    };
+    let mut options = cargo_dist::LinkageArgs {
+        print_output: args.print_output,
+        print_json: args.print_json,
+    };
+    if !args.print_output && !args.print_json {
+        options.print_output = true;
+    }
+    do_linkage(&config, &options)
+}
+
 fn cmd_generate_ci(cli: &Cli, args: &GenerateCiArgs) -> Result<(), miette::Report> {
     cmd_generate(
         cli,

cargo-dist/src/tasks.rs

@@ -458,7 +458,7 @@ pub struct Symbols {
 }
 
 /// A logical release of an application that artifacts are grouped under
-#[derive(Debug)]
+#[derive(Clone, Debug)]
 pub struct Release {
     /// The name of the app
     pub app_name: String,