From ef919f3d5216a12b6c80637ffd617db935dc4c96 Mon Sep 17 00:00:00 2001
From: Jeremy Soller <jeremy@system76.com>
Date: Sat, 22 Dec 2018 08:02:00 -0700
Subject: [PATCH] Implement EINTR for anything using wait_queue
---
src/event.rs | 4 ++--
src/scheme/debug.rs | 4 +++-
src/scheme/user.rs | 5 ++++-
src/sync/wait_map.rs | 1 +
src/sync/wait_queue.rs | 14 ++++++++------
5 files changed, 18 insertions(+), 10 deletions(-)
diff --git a/src/event.rs b/src/event.rs
index f7cef70a..dbe908f4 100644
--- a/src/event.rs
+++ b/src/event.rs
@@ -7,7 +7,7 @@ use context;
use scheme::{self, SchemeId};
use sync::WaitQueue;
use syscall::data::Event;
-use syscall::error::{Error, Result, EBADF, ESRCH};
+use syscall::error::{Error, Result, EBADF, EINTR, ESRCH};
int_like!(EventQueueId, AtomicEventQueueId, usize, AtomicUsize);
@@ -25,7 +25,7 @@ impl EventQueue {
}
pub fn read(&self, events: &mut [Event]) -> Result<usize> {
- Ok(self.queue.receive_into(events, true))
+ self.queue.receive_into(events, true).ok_or(Error::new(EINTR))
}
pub fn write(&self, events: &[Event]) -> Result<usize> {
diff --git a/src/scheme/debug.rs b/src/scheme/debug.rs
index 17e016fa..4f1cec5b 100644
--- a/src/scheme/debug.rs
+++ b/src/scheme/debug.rs
@@ -68,7 +68,9 @@ impl Scheme for DebugScheme {
*handles.get(&id).ok_or(Error::new(EBADF))?
};
- Ok(INPUT.call_once(init_input).receive_into(buf, flags & O_NONBLOCK != O_NONBLOCK))
+ INPUT.call_once(init_input)
+ .receive_into(buf, flags & O_NONBLOCK != O_NONBLOCK)
+ .ok_or(Error::new(EINTR))
}
/// Write the `buffer` to the `file`
diff --git a/src/scheme/user.rs b/src/scheme/user.rs
index f894d8ea..eab5704c 100644
--- a/src/scheme/user.rs
+++ b/src/scheme/user.rs
@@ -168,7 +168,10 @@ 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, self.flags & O_NONBLOCK != O_NONBLOCK) * mem::size_of::<Packet>())
+ self.todo
+ .receive_into(packet_buf, self.flags & O_NONBLOCK != O_NONBLOCK)
+ .map(|count| count * mem::size_of::<Packet>())
+ .ok_or(Error::new(EINTR))
}
pub fn write(&self, buf: &[u8]) -> Result<usize> {
diff --git a/src/sync/wait_map.rs b/src/sync/wait_map.rs
index 45c692af..aedcef50 100644
--- a/src/sync/wait_map.rs
+++ b/src/sync/wait_map.rs
@@ -27,6 +27,7 @@ impl<K, V> WaitMap<K, V> where K: Clone + Ord {
if let Some(value) = self.receive_nonblock(key) {
return value;
}
+ //TODO: use false from wait condition to indicate EINTR
let _ = self.condition.wait();
}
}
diff --git a/src/sync/wait_queue.rs b/src/sync/wait_queue.rs
index 384a125b..766ce895 100644
--- a/src/sync/wait_queue.rs
+++ b/src/sync/wait_queue.rs
@@ -28,20 +28,22 @@ impl<T> WaitQueue<T> {
self.inner.lock().is_empty()
}
- pub fn receive(&self) -> T {
+ pub fn receive(&self) -> Option<T> {
loop {
if let Some(value) = self.inner.lock().pop_front() {
- return value;
+ return Some(value);
+ }
+ if ! self.condition.wait() {
+ return None;
}
- let _ = self.condition.wait();
}
}
- pub fn receive_into(&self, buf: &mut [T], block: bool) -> usize {
+ pub fn receive_into(&self, buf: &mut [T], block: bool) -> Option<usize> {
let mut i = 0;
if i < buf.len() && block {
- buf[i] = self.receive();
+ buf[i] = self.receive()?;
i += 1;
}
@@ -57,7 +59,7 @@ impl<T> WaitQueue<T> {
}
}
- i
+ Some(i)
}
pub fn send(&self, value: T) -> usize {
--
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