Update repository and find the latest index

Ref: #6

cargo-install-update.md

@@ -16,7 +16,7 @@ Only updates packages from the main repository.
 
 Exit values and possible errors:
 
-    -1 - cargo install process was terminated by a signal (Linux-only)
+    -1 - cargo subprocess was terminated by a signal (Linux-only)
     1  - option parsing error
     X  - bubbled-up cargo install exit value
 

src/lib.rs

@@ -31,7 +31,7 @@
 //! Exit values and possible errors:
 //!
 //! ```text
-//! -1 - cargo install process was terminated by a signal (Linux-only)
+//! -1 - cargo subprocess was terminated by a signal (Linux-only)
 //! 1  - option parsing error
 //! X  - bubbled-up cargo install exit value
 //! ```

src/main.rs

@@ -20,6 +20,16 @@ fn actual_main() -> Result<(), i32> {
         packages = cargo_update::ops::intersect_packages(packages, &opts.to_update);
     }
 
+    {
+        // Searching for "" will just update the registry
+        let search_res = Command::new("cargo").arg("search").arg("").status().unwrap();
+        if !search_res.success() {
+            try!(Err(search_res.code().unwrap_or(-1)));
+        }
+    }
+
+    println!("Latest registry: {:?}", cargo_update::ops::get_index_path(&opts.cargo_dir.1));
+
     for package in &mut packages {
         package.pull_version();
     }

src/ops.rs

@@ -7,9 +7,9 @@
 
 
 use hyper::Client as HttpClient;
+use std::path::{PathBuf, Path};
 use semver::Version as Semver;
-use std::path::Path;
-use std::fs::File;
+use std::fs::{self, File};
 use std::io::Read;
 use regex::Regex;
 use toml;
@@ -229,3 +229,13 @@ pub fn crate_versions_raw(crate_name: &str) -> String {
 pub fn crate_versions(raw: &str) -> Vec<Semver> {
     json::parse(raw).unwrap()["versions"].members().map(|v| Semver::parse(v["num"].as_str().unwrap()).unwrap()).collect()
 }
+
+pub fn get_index_path(cargo_dir: &Path) -> PathBuf {
+    fs::read_dir(cargo_dir.join("registry").join("index"))
+        .unwrap()
+        .map(Result::unwrap)
+        .filter(|i| i.file_type().unwrap().is_dir())
+        .max_by_key(|i| i.metadata().unwrap().modified().unwrap())
+        .unwrap()
+        .path()
+}