From 6523f6edf5f841b3484346315eb05b86a2858f24 Mon Sep 17 00:00:00 2001
From: Matt Green <mattgreenrocks@gmail.com>
Date: Wed, 9 Nov 2016 17:00:24 -0500
Subject: [PATCH] Cleanup, initial Windows implementation of interrupt handler

---
 src/interrupt.rs | 40 ++++++++++++++++++++++++++++++----------
 src/main.rs      |  8 ++++----
 2 files changed, 34 insertions(+), 14 deletions(-)

diff --git a/src/interrupt.rs b/src/interrupt.rs
index 18034ae..fc56abe 100644
--- a/src/interrupt.rs
+++ b/src/interrupt.rs
@@ -1,3 +1,9 @@
+use std::sync::Mutex;
+
+lazy_static! {
+    static ref CLEANUP: Mutex<Option<Box<Fn() + Send>>> = Mutex::new(None);
+}
+
 #[cfg(unix)]
 pub fn install_handler<F>(handler: F)
     where F: Fn() + 'static + Send + Sync {
@@ -12,12 +18,14 @@ pub fn install_handler<F>(handler: F)
     mask.add(SIGINT);
     mask.thread_set_mask().expect("unable to set signal mask");
 
+    set_handler(handler);
+
     // Spawn a thread to catch these signals
     thread::spawn(move || {
         let sig = mask.wait().expect("unable to sigwait");
 
         // Invoke closure
-        handler();
+        invoke();
 
         // Restore default behavior for received signal and unmask it
         unsafe {
@@ -33,22 +41,34 @@ pub fn install_handler<F>(handler: F)
     });
 }
 
-/// On Windows, use SetConsoleCtrlHandler() to send an interrupt
-/// SetConsoleCtrlHandler runs in it's own thread, so it's safe.
 #[cfg(windows)]
-pub fn install() -> Receiver<()> {
+pub fn install_handler<F>(handler: F)
+    where F: Fn() + 'static + Send + Sync {
+
     use kernel32::SetConsoleCtrlHandler;
-    use winapi::{BOOL, DWORD, TRUE};
+    use winapi::{BOOL, DWORD, FALSE};
 
     pub unsafe extern "system" fn ctrl_handler(_: DWORD) -> BOOL {
-        let _ = send_interrupt();
-        TRUE
+        invoke();
+
+        FALSE
     }
 
-    let rx = create_channel();
+    set_handler(handler);
+
     unsafe {
         SetConsoleCtrlHandler(Some(ctrl_handler), TRUE);
     }
-
-    rx
+}
+
+fn invoke() {
+    if let Some(ref handler) = *CLEANUP.lock().unwrap() {
+        handler()
+    }
+}
+
+fn set_handler<F>(handler: F)
+    where F: Fn() + 'static + Send + Sync {
+
+    *CLEANUP.lock().unwrap() = Some(Box::new(handler));
 }
diff --git a/src/main.rs b/src/main.rs
index e43668e..badaa3d 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -80,8 +80,8 @@ fn init_logger(debug: bool) {
 
 fn main() {
     let child_process: Arc<RwLock<Option<Process>>> = Arc::new(RwLock::new(None));
-
     let weak_child = Arc::downgrade(&child_process);
+
     interrupt::install_handler(move || {
         if let Some(lock) = weak_child.upgrade() {
             let strong = lock.read().unwrap();
@@ -147,7 +147,7 @@ fn main() {
             debug!("Path updated: {:?}", path);
         }
 
-        //. Wait for current child process to exit
+        // Wait for current child process to exit
         {
             let guard = child_process.read().unwrap();
 
@@ -168,8 +168,8 @@ fn main() {
         }
 
         {
-            let mut lock = child_process.write().unwrap();
-            *lock = Process::new(&args.cmd, paths).ok();
+            let mut guard = child_process.write().unwrap();
+            *guard = Process::new(&args.cmd, paths).ok();
         }
     }
 }