From 9c3a06b8f97c2d7a332ac58508e1f36427bab90c Mon Sep 17 00:00:00 2001
From: Jeremy Soller <jackpot51@gmail.com>
Date: Thu, 20 Oct 2016 12:31:39 -0600
Subject: [PATCH] Add nonblocking root scheme
---
scheme/debug.rs | 2 +-
scheme/event.rs | 2 +-
scheme/root.rs | 4 ++--
scheme/user.rs | 8 +++++---
sync/wait_queue.rs | 35 +++++++++++------------------------
5 files changed, 20 insertions(+), 31 deletions(-)
diff --git a/scheme/debug.rs b/scheme/debug.rs
index e082ac65..27ab6261 100644
--- a/scheme/debug.rs
+++ b/scheme/debug.rs
@@ -41,7 +41,7 @@ impl Scheme for DebugScheme {
///
/// Returns the number of bytes read
fn read(&self, _file: usize, buf: &mut [u8]) -> Result<usize> {
- Ok(INPUT.call_once(init_input).receive_into(buf))
+ Ok(INPUT.call_once(init_input).receive_into(buf, true))
}
/// Write the `buffer` to the `file`
diff --git a/scheme/event.rs b/scheme/event.rs
index 1634e1b4..cca7420c 100644
--- a/scheme/event.rs
+++ b/scheme/event.rs
@@ -59,7 +59,7 @@ impl Scheme for EventScheme {
};
let event_buf = unsafe { slice::from_raw_parts_mut(buf.as_mut_ptr() as *mut Event, buf.len()/mem::size_of::<Event>()) };
- Ok(handle.receive_into(event_buf) * mem::size_of::<Event>())
+ Ok(handle.receive_into(event_buf, true) * mem::size_of::<Event>())
}
fn fsync(&self, id: usize) -> Result<usize> {
diff --git a/scheme/root.rs b/scheme/root.rs
index 57877bf8..a2531328 100644
--- a/scheme/root.rs
+++ b/scheme/root.rs
@@ -27,7 +27,7 @@ impl RootScheme {
}
impl Scheme for RootScheme {
- fn open(&self, path: &[u8], _flags: usize, uid: u32, _gid: u32) -> Result<usize> {
+ fn open(&self, path: &[u8], flags: usize, uid: u32, _gid: u32) -> Result<usize> {
if uid == 0 {
let context = {
let contexts = context::contexts();
@@ -42,7 +42,7 @@ impl Scheme for RootScheme {
if schemes.get_name(path).is_some() {
return Err(Error::new(EEXIST));
}
- let inner = Arc::new(UserInner::new(id, context));
+ let inner = Arc::new(UserInner::new(id, flags, context));
let scheme_id = schemes.insert(path.to_vec().into_boxed_slice(), Arc::new(Box::new(UserScheme::new(Arc::downgrade(&inner))))).expect("failed to insert user scheme");
inner.scheme_id.store(scheme_id, Ordering::SeqCst);
inner
diff --git a/scheme/user.rs b/scheme/user.rs
index c2d8650f..8f1c95a7 100644
--- a/scheme/user.rs
+++ b/scheme/user.rs
@@ -12,12 +12,13 @@ use scheme::root::ROOT_SCHEME_ID;
use sync::{WaitQueue, WaitMap};
use syscall::data::{Packet, Stat};
use syscall::error::*;
-use syscall::flag::EVENT_READ;
+use syscall::flag::{EVENT_READ, O_NONBLOCK};
use syscall::number::*;
use syscall::scheme::Scheme;
pub struct UserInner {
handle_id: usize,
+ flags: usize,
pub scheme_id: AtomicUsize,
next_id: AtomicU64,
context: Weak<RwLock<Context>>,
@@ -26,9 +27,10 @@ pub struct UserInner {
}
impl UserInner {
- pub fn new(handle_id: usize, context: Weak<RwLock<Context>>) -> UserInner {
+ pub fn new(handle_id: usize, flags: usize, context: Weak<RwLock<Context>>) -> UserInner {
UserInner {
handle_id: handle_id,
+ flags: flags,
scheme_id: AtomicUsize::new(0),
next_id: AtomicU64::new(1),
context: context,
@@ -158,7 +160,7 @@ impl UserInner {
pub fn read(&self, buf: &mut [u8]) -> Result<usize> {
let packet_buf = unsafe { slice::from_raw_parts_mut(buf.as_mut_ptr() as *mut Packet, buf.len()/mem::size_of::<Packet>()) };
- Ok(self.todo.receive_into(packet_buf) * mem::size_of::<Packet>())
+ Ok(self.todo.receive_into(packet_buf, self.flags & O_NONBLOCK != O_NONBLOCK) * mem::size_of::<Packet>())
}
pub fn write(&self, buf: &[u8]) -> Result<usize> {
diff --git a/sync/wait_queue.rs b/sync/wait_queue.rs
index 445164c4..fdf81b54 100644
--- a/sync/wait_queue.rs
+++ b/sync/wait_queue.rs
@@ -1,6 +1,4 @@
use collections::vec_deque::VecDeque;
-use core::mem;
-use core::ops::DerefMut;
use spin::Mutex;
use sync::WaitCondition;
@@ -39,40 +37,29 @@ impl<T> WaitQueue<T> {
}
}
- pub fn receive_into(&self, buf: &mut [T]) -> usize {
+ pub fn receive_into(&self, buf: &mut [T], block: bool) -> usize {
let mut i = 0;
- if i < buf.len() {
+ if i < buf.len() && block {
buf[i] = self.receive();
i += 1;
}
- while i < buf.len() {
- if let Some(value) = self.inner.lock().pop_front() {
- buf[i] = value;
- i += 1;
- } else {
- break;
+ {
+ let mut inner = self.inner.lock();
+ while i < buf.len() {
+ if let Some(value) = inner.pop_front() {
+ buf[i] = value;
+ i += 1;
+ } else {
+ break;
+ }
}
}
i
}
- pub fn receive_all(&self) -> VecDeque<T> {
- loop {
- {
- let mut inner = self.inner.lock();
- if ! inner.is_empty() {
- let mut swap_inner = VecDeque::new();
- mem::swap(inner.deref_mut(), &mut swap_inner);
- return swap_inner;
- }
- }
- self.condition.wait();
- }
- }
-
pub fn send(&self, value: T) -> usize {
let len = {
let mut inner = self.inner.lock();
--
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