From d383cfb595327f320a614db4a78062cc53682d65 Mon Sep 17 00:00:00 2001
From: Jeremy Soller <jackpot51@gmail.com>
Date: Tue, 16 Aug 2016 11:04:14 -0600
Subject: [PATCH] Lazy static init of schemes

---
 Cargo.toml           |  2 ++
 kernel/lib.rs        |  9 ++++++---
 kernel/scheme/mod.rs | 15 ++++++++++++++-
 kernel/syscall/fs.rs | 22 ++++++++++++++++++----
 4 files changed, 40 insertions(+), 8 deletions(-)

diff --git a/Cargo.toml b/Cargo.toml
index 5b0c6c2..9e59f9f 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -9,6 +9,8 @@ crate-type = ["staticlib"]
 
 [dependencies]
 bitflags = "*"
+lazy_static = "*"
+spin = "*"
 
 [dev-dependencies]
 arch_test = { path = "arch/test" }
diff --git a/kernel/lib.rs b/kernel/lib.rs
index 257c9dd..0768a61 100644
--- a/kernel/lib.rs
+++ b/kernel/lib.rs
@@ -70,9 +70,6 @@
 #![feature(question_mark)]
 #![no_std]
 
-#[macro_use]
-extern crate bitflags;
-
 use arch::interrupt::{enable_interrupts, halt};
 
 /// Architecture specific items (test)
@@ -89,6 +86,12 @@ extern crate alloc;
 #[macro_use]
 extern crate collections;
 
+#[macro_use]
+extern crate bitflags;
+#[macro_use]
+extern crate lazy_static;
+extern crate spin;
+
 /// Context management
 pub mod context;
 
diff --git a/kernel/scheme/mod.rs b/kernel/scheme/mod.rs
index b99cc72..176407b 100644
--- a/kernel/scheme/mod.rs
+++ b/kernel/scheme/mod.rs
@@ -6,6 +6,13 @@
 //! The kernel validates paths and file descriptors before they are passed to schemes,
 //! also stripping the scheme identifier of paths if necessary.
 
+use alloc::arc::Arc;
+use alloc::boxed::Box;
+
+use collections::BTreeMap;
+
+use spin::{Mutex, RwLock};
+
 use syscall::Result;
 
 use self::debug::DebugScheme;
@@ -14,7 +21,13 @@ use self::debug::DebugScheme;
 pub mod debug;
 
 /// Schemes list
-pub static mut SCHEME: DebugScheme = DebugScheme;
+lazy_static! {
+    pub static ref SCHEMES: RwLock<BTreeMap<Box<[u8]>, Arc<Mutex<Box<Scheme + Send>>>>> = {
+        let mut map: BTreeMap<Box<[u8]>, Arc<Mutex<Box<Scheme + Send>>>> = BTreeMap::new();
+        map.insert(Box::new(*b"debug"), Arc::new(Mutex::new(Box::new(DebugScheme))));
+        RwLock::new(map)
+    };
+}
 
 /// A scheme trait, implemented by a scheme handler
 pub trait Scheme {
diff --git a/kernel/syscall/fs.rs b/kernel/syscall/fs.rs
index e632b75..1deedc8 100644
--- a/kernel/syscall/fs.rs
+++ b/kernel/syscall/fs.rs
@@ -1,7 +1,5 @@
 //! Filesystem syscalls
 
-use scheme::Scheme;
-
 use super::{Error, Result};
 
 /// Read syscall
@@ -28,8 +26,24 @@ pub fn write(fd: usize, buf: &[u8]) -> Result<usize> {
 
 /// Open syscall
 pub fn open(path: &[u8], flags: usize) -> Result<usize> {
-    println!("Open {:?}: {:X}", ::core::str::from_utf8(path), flags);
-    let file = unsafe { &mut ::scheme::SCHEME }.open(path, flags)?;
+    let mut parts = path.splitn(2, |&b| b == b':');
+    let namespace_opt = parts.next();
+    let reference_opt = parts.next();
+    println!("Open namespace {:?} reference {:?}: {:X}", namespace_opt.map(::core::str::from_utf8), reference_opt.map(::core::str::from_utf8), flags);
+
+    let file = {
+        if let Some(namespace) = namespace_opt {
+            let schemes = ::scheme::SCHEMES.read();
+            if let Some(scheme_mutex) = schemes.get(namespace) {
+                scheme_mutex.lock().open(reference_opt.unwrap_or(b""), flags)
+            } else {
+                Err(Error::NoEntry)
+            }
+        } else {
+            Err(Error::NoEntry)
+        }
+    }?;
+
     if let Some(fd) = unsafe { &mut ::context::CONTEXT }.add_file(::context::file::File {
         scheme: 0,
         number: file