From 32fa7cbda8afc17da644088ad726cec62ac3228d Mon Sep 17 00:00:00 2001
From: Diego Giagio <diego@giagio.com>
Date: Mon, 15 Oct 2018 02:25:19 +0200
Subject: [PATCH] Honor the exit code from the child in the parent

---
 warp-runner/src/executor.rs | 33 ++++++++++++++++---------
 warp-runner/src/main.rs     | 49 ++++++++++++++++++++++---------------
 2 files changed, 50 insertions(+), 32 deletions(-)

diff --git a/warp-runner/src/executor.rs b/warp-runner/src/executor.rs
index 757da82..7af2978 100644
--- a/warp-runner/src/executor.rs
+++ b/warp-runner/src/executor.rs
@@ -2,6 +2,7 @@ use std::env;
 use std::process::Command;
 use std::process::Stdio;
 use std::path::Path;
+use std::io;
 
 #[cfg(target_family = "windows")]
 const PATH_SEPARATOR: char = ';';
@@ -9,23 +10,31 @@ const PATH_SEPARATOR: char = ';';
 #[cfg(target_family = "unix")]
 const PATH_SEPARATOR: char = ':';
 
-pub fn execute(path: &Path, prog: &str) {
-    let path_str = path.as_os_str().to_os_string().into_string().unwrap();
-    let path_env = match env::var("PATH") {
-        Ok(p) => format!("{}{}{}", &path_str, PATH_SEPARATOR, &p),
-        _ => path_str
-    };
+pub fn execute(target: &Path) -> io::Result<i32> {
+    let target_dir = target.parent()
+        .and_then(|dir| dir.to_str())
+        .expect("Unable to construct target directory");
+    let target_file_name = target.file_name()
+        .and_then(|file_name| file_name.to_str())
+        .expect("Unable to identify target file name");
+    trace!("target={:?}", target);
+    trace!("target_dir={:?}", target_dir);
+    trace!("target_file_name={:?}", target_file_name);
+
+    let current_path_env = env::var("PATH").unwrap_or(String::new());
+    let path_env = format!("{}{}{}", target_dir, PATH_SEPARATOR, current_path_env);
+    trace!("path_env={:?}", path_env);
 
     let args: Vec<String> = env::args().skip(1).collect();
-    trace!("PATH={:?} prog={:?} args={:?}", path_env, prog, args);
-    Command::new(prog)
+    trace!("args={:?}", args);
+
+    Ok(Command::new(target_file_name)
         .env("PATH", path_env)
         .args(args)
         .stdin(Stdio::inherit())
         .stdout(Stdio::inherit())
         .stderr(Stdio::inherit())
-        .spawn()
-        .unwrap_or_else(|_| panic!("{} failed to start", prog))
-        .wait()
-        .unwrap_or_else(|_| panic!("{} failed to wait", prog));
+        .spawn()?
+        .wait()?
+        .code().unwrap_or(1))
 }
diff --git a/warp-runner/src/main.rs b/warp-runner/src/main.rs
index f198199..f711f4c 100644
--- a/warp-runner/src/main.rs
+++ b/warp-runner/src/main.rs
@@ -1,40 +1,40 @@
 extern crate dirs;
-
 #[macro_use]
 extern crate log;
 extern crate simple_logger;
 
+use log::Level;
 use std::env;
 use std::error::Error;
 use std::ffi::*;
 use std::fs;
 use std::io;
 use std::path::*;
-use log::Level;
+use std::process;
 
 mod extractor;
 mod executor;
 
-static PROG_BUF: &'static [u8] = b"tVQhhsFFlGGD3oWV4lEPST8I8FEPP54IM0q7daes4E1y3p2U2wlJRYmWmjPYfkhZ0PlT14Ls0j8fdDkoj33f2BlRJavLj3mWGibJsGt5uLAtrCDtvxikZ8UX2mQDCrgE\0";
+static TARGET_FILE_NAME_BUF: &'static [u8] = b"tVQhhsFFlGGD3oWV4lEPST8I8FEPP54IM0q7daes4E1y3p2U2wlJRYmWmjPYfkhZ0PlT14Ls0j8fdDkoj33f2BlRJavLj3mWGibJsGt5uLAtrCDtvxikZ8UX2mQDCrgE\0";
 
-fn prog() -> &'static str {
-    let nul_pos = PROG_BUF.iter()
+fn target_file_name() -> &'static str {
+    let nul_pos = TARGET_FILE_NAME_BUF.iter()
         .position(|elem| *elem == b'\0')
-        .expect("PROG_BUF has no NUL terminator");
+        .expect("TARGET_FILE_NAME_BUF has no NUL terminator");
 
-    let slice = &PROG_BUF[..(nul_pos + 1)];
+    let slice = &TARGET_FILE_NAME_BUF[..(nul_pos + 1)];
     CStr::from_bytes_with_nul(slice)
-        .expect("Can't convert PROG_BUF slice to CStr")
+        .expect("Can't convert TARGET_FILE_NAME_BUF slice to CStr")
         .to_str()
-        .expect("Can't convert PROG_BUF CStr to str")
+        .expect("Can't convert TARGET_FILE_NAME_BUF CStr to str")
 }
 
-fn cache_path(prog: &str) -> PathBuf {
+fn cache_path(target: &str) -> PathBuf {
     dirs::data_local_dir()
         .expect("No data local dir found")
         .join("warp")
         .join("packages")
-        .join(prog)
+        .join(target)
 }
 
 fn extract(exe_path: &Path, cache_path: &Path) -> io::Result<()> {
@@ -48,26 +48,35 @@ fn main() -> Result<(), Box<Error>> {
         simple_logger::init_with_level(Level::Trace)?;
     }
 
-    let prog = prog();
-    let cache_path = cache_path(prog);
-    let exe_path = env::current_exe()?;
-    trace!("prog={:?}, cache_path={:?}, exe_path={:?}", prog, cache_path, exe_path);
+    let self_path = env::current_exe()?;
+    let self_file_name = self_path.file_name().unwrap();
+    let cache_path = cache_path(&self_file_name.to_string_lossy());
+
+    trace!("self_path={:?}", self_path);
+    trace!("self_file_name={:?}", self_file_name);
+    trace!("cache_path={:?}", cache_path);
+
+    let target_file_name = target_file_name();
+    let target_path = cache_path.join(target_file_name);
+
+    trace!("target_exec={:?}", target_file_name);
+    trace!("target_path={:?}", target_path);
 
     match fs::metadata(&cache_path) {
         Ok(cache) => {
-            if cache.modified()? >= fs::metadata(&exe_path)?.modified()? {
+            if cache.modified()? >= fs::metadata(&self_path)?.modified()? {
                 trace!("cache is up-to-date");
             } else {
                 trace!("cache is outdated");
-                extract(&exe_path, &cache_path)?;
+                extract(&self_path, &cache_path)?;
             }
         }
         Err(_) => {
             trace!("cache not found");
-            extract(&exe_path, &cache_path)?;
+            extract(&self_path, &cache_path)?;
         }
     }
 
-    executor::execute(&cache_path, &prog);
-    Ok(())
+    let exit_code = executor::execute(&target_path)?;
+    process::exit(exit_code);
 }