From a3493d16fdd26b7422282b7b07b30db74089cb56 Mon Sep 17 00:00:00 2001
From: Jeremy Soller <jackpot51@gmail.com>
Date: Mon, 10 Jul 2017 20:28:10 -0600
Subject: [PATCH] Allow simple signal delivery to PID 1 (the kernel idle
 process)

---
 src/context/context.rs |  2 +-
 src/context/switch.rs  | 15 ++++-----------
 2 files changed, 5 insertions(+), 12 deletions(-)

diff --git a/src/context/context.rs b/src/context/context.rs
index bae447e..d971cee 100644
--- a/src/context/context.rs
+++ b/src/context/context.rs
@@ -66,7 +66,7 @@ pub struct Context {
     /// Kernel stack
     pub kstack: Option<Box<[u8]>>,
     /// Kernel signal backup
-    pub ksig: Option<(arch::Context, Box<[u8]>, Box<[u8]>)>,
+    pub ksig: Option<(arch::Context, Option<Box<[u8]>>, Option<Box<[u8]>>)>,
     /// Restore ksig context on next switch
     pub ksig_restore: bool,
     /// Executable image
diff --git a/src/context/switch.rs b/src/context/switch.rs
index 4706a11..d231eed 100644
--- a/src/context/switch.rs
+++ b/src/context/switch.rs
@@ -53,12 +53,12 @@ pub unsafe fn switch() -> bool {
                 let ksig = context.ksig.take().expect("context::switch: ksig not set with ksig_restore");
                 context.arch = ksig.0;
                 if let Some(ref mut kfx) = context.kfx {
-                    kfx.clone_from_slice(&ksig.1);
+                    kfx.clone_from_slice(&ksig.1.expect("context::switch: ksig kfx not set with ksig_restore"));
                 } else {
                     panic!("context::switch: kfx not set with ksig_restore");
                 }
                 if let Some(ref mut kstack) = context.kstack {
-                    kstack.clone_from_slice(&ksig.2);
+                    kstack.clone_from_slice(&ksig.2.expect("context::switch: ksig kstack not set with ksig_restore"));
                 } else {
                     panic!("context::switch: kstack not set with ksig_restore");
                 }
@@ -139,15 +139,8 @@ pub unsafe fn switch() -> bool {
         assert!((&mut *to_ptr).ksig.is_none());
 
         let arch = (&mut *to_ptr).arch.clone();
-        let kfx = match (&mut *to_ptr).kfx {
-            Some(ref kfx) => kfx.clone(),
-            None => panic!("context::switch: no kfx during signal")
-        };
-        let kstack = match (&mut *to_ptr).kstack {
-            Some(ref kstack) => kstack.clone(),
-            None => panic!("context::switch: no kstack during signal")
-        };
-
+        let kfx = (&mut *to_ptr).kfx.clone();
+        let kstack = (&mut *to_ptr).kstack.clone();
         (&mut *to_ptr).ksig = Some((arch, kfx, kstack));
         (&mut *to_ptr).arch.signal_stack(signal_handler, sig);
     }