Runtime removal: fully remove rtio

This patch cleans up the remnants of the runtime IO interface.

Because this eliminates APIs in `libnative` and `librustrt`, it is a:

[breaking-change]

This functionality is likely to be available publicly, in some form,
from `std` in the future.

Author: aturon

src/libgreen/basic.rs

@@ -18,7 +18,7 @@
 use alloc::arc::Arc;
 use std::sync::atomic;
 use std::mem;
-use std::rt::rtio::{EventLoop, IoFactory, RemoteCallback};
+use std::rt::rtio::{EventLoop, RemoteCallback};
 use std::rt::rtio::{PausableIdleCallback, Callback};
 use std::rt::exclusive::Exclusive;
 
@@ -150,8 +150,6 @@ impl EventLoop for BasicLoop {
             Box<RemoteCallback + Send>
     }
 
-    fn io<'a>(&'a mut self) -> Option<&'a mut IoFactory> { None }
-
     fn has_active_io(&self) -> bool { false }
 }
 

src/libgreen/simple.rs

@@ -16,7 +16,6 @@ use std::mem;
 use std::rt::Runtime;
 use std::rt::local::Local;
 use std::rt::mutex::NativeMutex;
-use std::rt::rtio;
 use std::rt::task::{Task, BlockedTask, TaskOpts};
 
 struct SimpleTask {
@@ -79,9 +78,10 @@ impl Runtime for SimpleTask {
                      _f: proc():Send) {
         panic!()
     }
-    fn local_io<'a>(&'a mut self) -> Option<rtio::LocalIo<'a>> { None }
+
     fn stack_bounds(&self) -> (uint, uint) { panic!() }
     fn stack_guard(&self) -> Option<uint> { panic!() }
+
     fn can_block(&self) -> bool { true }
     fn wrap(self: Box<SimpleTask>) -> Box<Any+'static> { panic!() }
 }

src/libgreen/task.rs

@@ -24,7 +24,6 @@ use std::raw;
 use std::rt::Runtime;
 use std::rt::local::Local;
 use std::rt::mutex::NativeMutex;
-use std::rt::rtio;
 use std::rt::stack;
 use std::rt::task::{Task, BlockedTask, TaskOpts};
 use std::rt;
@@ -468,14 +467,6 @@ impl Runtime for GreenTask {
         sched.run_task(me, sibling)
     }
 
-    // Local I/O is provided by the scheduler's event loop
-    fn local_io<'a>(&'a mut self) -> Option<rtio::LocalIo<'a>> {
-        match self.sched.as_mut().unwrap().event_loop.io() {
-            Some(io) => Some(rtio::LocalIo::new(io)),
-            None => None,
-        }
-    }
-
     fn stack_bounds(&self) -> (uint, uint) {
         let c = self.coroutine.as_ref()
             .expect("GreenTask.stack_bounds called without a coroutine");

src/libnative/io/mod.rs

@@ -74,7 +74,6 @@ use std::str;
 
 pub use task::NativeTaskBuilder;
 
-pub mod io;
 pub mod task;
 
 #[cfg(any(windows, android))]

src/libnative/lib.rs

@@ -19,13 +19,11 @@ use std::mem;
 use std::rt::bookkeeping;
 use std::rt::local::Local;
 use std::rt::mutex::NativeMutex;
-use std::rt::rtio;
 use std::rt::stack;
 use std::rt::task::{Task, BlockedTask, TaskOpts};
 use std::rt::thread::Thread;
 use std::rt;
 
-use io;
 use std::task::{TaskBuilder, Spawner};
 
 /// Creates a new Task which is ready to execute as a 1:1 task.
@@ -42,7 +40,6 @@ fn ops() -> Box<Ops> {
     box Ops {
         lock: unsafe { NativeMutex::new() },
         awoken: false,
-        io: io::IoFactory::new(),
         // these *should* get overwritten
         stack_bounds: (0, 0),
         stack_guard: 0
@@ -112,7 +109,6 @@ impl<S: Spawner> NativeTaskBuilder for TaskBuilder<S> {
 struct Ops {
     lock: NativeMutex,       // native synchronization
     awoken: bool,      // used to prevent spurious wakeups
-    io: io::IoFactory, // local I/O factory
 
     // This field holds the known bounds of the stack in (lo, hi) form. Not all
     // native tasks necessarily know their precise bounds, hence this is
@@ -272,10 +268,6 @@ impl rt::Runtime for Ops {
 
         NativeSpawner.spawn(opts, f);
     }
-
-    fn local_io<'a>(&'a mut self) -> Option<rtio::LocalIo<'a>> {
-        Some(rtio::LocalIo::new(&mut self.io as &mut rtio::IoFactory))
-    }
 }
 
 #[cfg(test)]

src/libnative/task.rs

@@ -90,7 +90,6 @@ pub trait Runtime {
                      cur_task: Box<Task>,
                      opts: TaskOpts,
                      f: proc():Send);
-    fn local_io<'a>(&'a mut self) -> Option<rtio::LocalIo<'a>>;
     /// The (low, high) edges of the current stack.
     fn stack_bounds(&self) -> (uint, uint); // (lo, hi)
     /// The last writable byte of the stack next to the guard page

src/librustrt/lib.rs

@@ -12,12 +12,6 @@
 
 use core::prelude::*;
 use alloc::boxed::Box;
-use collections::string::String;
-use core::mem;
-use libc::c_int;
-
-use local::Local;
-use task::Task;
 
 pub trait EventLoop {
     fn run(&mut self);
@@ -27,8 +21,7 @@ pub trait EventLoop {
     fn remote_callback(&mut self, Box<Callback + Send>)
                        -> Box<RemoteCallback + Send>;
 
-    /// The asynchronous I/O services. Not all event loops may provide one.
-    fn io<'a>(&'a mut self) -> Option<&'a mut IoFactory>;
+    // last vestige of IoFactory
     fn has_active_io(&self) -> bool;
 }
 
@@ -46,128 +39,7 @@ pub trait RemoteCallback {
     fn fire(&mut self);
 }
 
-pub struct LocalIo<'a> {
-    factory: &'a mut IoFactory+'a,
-}
-
-#[unsafe_destructor]
-impl<'a> Drop for LocalIo<'a> {
-    fn drop(&mut self) {
-        // FIXME(pcwalton): Do nothing here for now, but eventually we may want
-        // something. For now this serves to make `LocalIo` noncopyable.
-    }
-}
-
-impl<'a> LocalIo<'a> {
-    /// Returns the local I/O: either the local scheduler's I/O services or
-    /// the native I/O services.
-    pub fn borrow() -> Option<LocalIo<'a>> {
-        // FIXME(#11053): bad
-        //
-        // This is currently very unsafely implemented. We don't actually
-        // *take* the local I/O so there's a very real possibility that we
-        // can have two borrows at once. Currently there is not a clear way
-        // to actually borrow the local I/O factory safely because even if
-        // ownership were transferred down to the functions that the I/O
-        // factory implements it's just too much of a pain to know when to
-        // relinquish ownership back into the local task (but that would be
-        // the safe way of implementing this function).
-        //
-        // In order to get around this, we just transmute a copy out of the task
-        // in order to have what is likely a static lifetime (bad).
-        let mut t: Box<Task> = match Local::try_take() {
-            Some(t) => t,
-            None => return None,
-        };
-        let ret = t.local_io().map(|t| {
-            unsafe { mem::transmute_copy(&t) }
-        });
-        Local::put(t);
-        return ret;
-    }
-
-    pub fn maybe_raise<T>(f: |io: &mut IoFactory| -> IoResult<T>)
-        -> IoResult<T>
-    {
-        #[cfg(unix)] use libc::EINVAL as ERROR;
-        #[cfg(windows)] use libc::ERROR_CALL_NOT_IMPLEMENTED as ERROR;
-        match LocalIo::borrow() {
-            Some(mut io) => f(io.get()),
-            None => Err(IoError {
-                code: ERROR as uint,
-                extra: 0,
-                detail: None,
-            }),
-        }
-    }
-
-    pub fn new<'a>(io: &'a mut IoFactory+'a) -> LocalIo<'a> {
-        LocalIo { factory: io }
-    }
-
-    /// Returns the underlying I/O factory as a trait reference.
-    #[inline]
-    pub fn get<'a>(&'a mut self) -> &'a mut IoFactory {
-        let f: &'a mut IoFactory = self.factory;
-        f
-    }
-}
-
-pub trait IoFactory {
-    fn timer_init(&mut self) -> IoResult<Box<RtioTimer + Send>>;
-    fn tty_open(&mut self, fd: c_int, readable: bool)
-            -> IoResult<Box<RtioTTY + Send>>;
-}
-
-pub trait RtioTimer {
-    fn sleep(&mut self, msecs: u64);
-    fn oneshot(&mut self, msecs: u64, cb: Box<Callback + Send>);
-    fn period(&mut self, msecs: u64, cb: Box<Callback + Send>);
-}
-
-pub trait RtioPipe {
-    fn read(&mut self, buf: &mut [u8]) -> IoResult<uint>;
-    fn write(&mut self, buf: &[u8]) -> IoResult<()>;
-    fn clone(&self) -> Box<RtioPipe + Send>;
-
-    fn close_write(&mut self) -> IoResult<()>;
-    fn close_read(&mut self) -> IoResult<()>;
-    fn set_timeout(&mut self, timeout_ms: Option<u64>);
-    fn set_read_timeout(&mut self, timeout_ms: Option<u64>);
-    fn set_write_timeout(&mut self, timeout_ms: Option<u64>);
-}
-
-pub trait RtioUnixListener {
-    fn listen(self: Box<Self>) -> IoResult<Box<RtioUnixAcceptor + Send>>;
-}
-
-pub trait RtioUnixAcceptor {
-    fn accept(&mut self) -> IoResult<Box<RtioPipe + Send>>;
-    fn set_timeout(&mut self, timeout: Option<u64>);
-    fn clone(&self) -> Box<RtioUnixAcceptor + Send>;
-    fn close_accept(&mut self) -> IoResult<()>;
-}
-
-pub trait RtioTTY {
-    fn read(&mut self, buf: &mut [u8]) -> IoResult<uint>;
-    fn write(&mut self, buf: &[u8]) -> IoResult<()>;
-    fn set_raw(&mut self, raw: bool) -> IoResult<()>;
-    fn get_winsize(&mut self) -> IoResult<(int, int)>;
-    fn isatty(&self) -> bool;
-}
-
 pub trait PausableIdleCallback {
     fn pause(&mut self);
     fn resume(&mut self);
 }
-
-pub trait RtioSignal {}
-
-#[deriving(Show)]
-pub struct IoError {
-    pub code: uint,
-    pub extra: uint,
-    pub detail: Option<String>,
-}
-
-pub type IoResult<T> = Result<T, IoError>;

src/librustrt/rtio.rs

@@ -26,7 +26,6 @@ use core::raw;
 use local_data;
 use Runtime;
 use local::Local;
-use rtio::LocalIo;
 use unwind;
 use unwind::Unwinder;
 use collections::str::SendStr;
@@ -421,13 +420,6 @@ impl Task {
         ops.maybe_yield(self);
     }
 
-    /// Acquires a handle to the I/O factory that this task contains, normally
-    /// stored in the task's runtime. This factory may not always be available,
-    /// which is why the return type is `Option`
-    pub fn local_io<'a>(&'a mut self) -> Option<LocalIo<'a>> {
-        self.imp.as_mut().unwrap().local_io()
-    }
-
     /// Returns the stack bounds for this task in (lo, hi) format. The stack
     /// bounds may not be known for all tasks, so the return value may be
     /// `None`.