auto merge of #5960 : brson/rust/io, r=pcwalton

r?

This pull request is a grab bag of work on the new scheduler.

The most important commit here is where I [outline](https://github.com/brson/rust/blob/io/src/libcore/rt/io/mod.rs) a fairly complete I/O API, based on `Reader` and `Writer` types, as in the current `core::io` module. I've organized this version into a number of modules with declarations for Files, TCP, UDP, Unix sockets, blocking/non-blocking implementations, memory buffers, compression adapters. I'm trying to get this into shape to present on the mailing list.

This branch also wires up `spawn` to the new scheduler, and simplifies the core scheduler operations.

src/libcore/rt/io/comm_adapters.rs

@@ -0,0 +1,59 @@
+// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+use prelude::*;
+use super::{Reader, Writer};
+
+struct PortReader<P>;
+
+impl<P: GenericPort<~[u8]>> PortReader<P> {
+    pub fn new(_port: P) -> PortReader<P> { fail!() }
+}
+
+impl<P: GenericPort<~[u8]>> Reader for PortReader<P> {
+    fn read(&mut self, _buf: &mut [u8]) -> Option<uint> { fail!() }
+
+    fn eof(&mut self) -> bool { fail!() }
+}
+
+struct ChanWriter<C>;
+
+impl<C: GenericChan<~[u8]>> ChanWriter<C> {
+    pub fn new(_chan: C) -> ChanWriter<C> { fail!() }
+}
+
+impl<C: GenericChan<~[u8]>> Writer for ChanWriter<C> {
+    pub fn write(&mut self, _buf: &[u8]) { fail!() }
+
+    pub fn flush(&mut self) { fail!() }
+}
+
+struct ReaderPort<R>;
+
+impl<R: Reader> ReaderPort<R> {
+    pub fn new(_reader: R) -> ReaderPort<R> { fail!() }
+}
+
+impl<R: Reader> GenericPort<~[u8]> for ReaderPort<R> {
+    fn recv(&self) -> ~[u8] { fail!() }
+
+    fn try_recv(&self) -> Option<~[u8]> { fail!() }
+}
+
+struct WriterChan<W>;
+
+impl<W: Writer> WriterChan<W> {
+    pub fn new(_writer: W) -> WriterChan<W> { fail!() }
+}
+
+impl<W: Writer> GenericChan<~[u8]> for WriterChan<W> {
+    fn send(&self, _x: ~[u8]) { fail!() }
+}
+

src/libcore/rt/io/file.rs

@@ -9,35 +9,79 @@
 // except according to those terms.
 
 use prelude::*;
-use super::Stream;
+use super::misc::PathLike;
+use super::{Reader, Writer, Seek, Close};
+use super::{IoError, SeekStyle};
+
+/// Open a file with the default FileMode and FileAccess
+/// # XXX are there sane defaults here?
+pub fn open_file<P: PathLike>(_path: &P) -> FileStream { fail!() }
+
+/// # XXX
+/// * Ugh, this is ridiculous. What is the best way to represent these options?
+enum FileMode {
+    /// Opens an existing file. IoError if file does not exist.
+    Open,
+    /// Creates a file. IoError if file exists.
+    Create,
+    /// Opens an existing file or creates a new one.
+    OpenOrCreate,
+    /// Opens an existing file or creates a new one, positioned at EOF.
+    Append,
+    /// Opens an existing file, truncating it to 0 bytes.
+    Truncate,
+    /// Opens an existing file or creates a new one, truncating it to 0 bytes.
+    CreateOrTruncate,
+}
+
+enum FileAccess {
+    Read,
+    Write,
+    ReadWrite
+}
 
 pub struct FileStream;
 
-pub impl FileStream {
-    fn new(_path: Path) -> FileStream {
+impl FileStream {
+    pub fn open<P: PathLike>(_path: &P,
+                             _mode: FileMode,
+                             _access: FileAccess
+                            ) -> Result<FileStream, IoError> {
         fail!()
     }
 }
 
-impl Stream for FileStream {
-    fn read(&mut self, _buf: &mut [u8]) -> uint {
+impl Reader for FileStream {
+    fn read(&mut self, _buf: &mut [u8]) -> Option<uint> {
         fail!()
     }
 
     fn eof(&mut self) -> bool {
         fail!()
     }
+}
 
-    fn write(&mut self, _v: &const [u8]) {
-        fail!()
-    }
+impl Writer for FileStream {
+    fn write(&mut self, _v: &[u8]) { fail!() }
+
+    fn flush(&mut self) { fail!() }
+}
+
+impl Seek for FileStream {
+    fn tell(&self) -> u64 { fail!() }
+
+    fn seek(&mut self, _pos: i64, _style: SeekStyle) { fail!() }
+}
+
+impl Close for FileStream {
+    fn close(&mut self) { fail!() }
 }
 
 #[test]
 #[ignore]
 fn super_simple_smoke_test_lets_go_read_some_files_and_have_a_good_time() {
     let message = "it's alright. have a good time";
-    let filename = Path("test.txt");
-    let mut outstream = FileStream::new(filename);
+    let filename = &Path("test.txt");
+    let mut outstream = FileStream::open(filename, Create, Read).unwrap();
     outstream.write(message.to_bytes());
 }

src/libcore/rt/io/flate.rs

@@ -0,0 +1,121 @@
+// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+//! Some various other I/O types
+
+// NOTE: These ultimately belong somewhere else
+
+use prelude::*;
+use super::*;
+
+/// A Writer decorator that compresses using the 'deflate' scheme
+pub struct DeflateWriter<W> {
+    inner_writer: W
+}
+
+impl<W: Writer> DeflateWriter<W> {
+    pub fn new(inner_writer: W) -> DeflateWriter<W> {
+        DeflateWriter {
+            inner_writer: inner_writer
+        }
+    }
+}
+
+impl<W: Writer> Writer for DeflateWriter<W> {
+    fn write(&mut self, _buf: &[u8]) { fail!() }
+
+    fn flush(&mut self) { fail!() }
+}
+
+impl<W: Writer> Decorator<W> for DeflateWriter<W> {
+    fn inner(self) -> W {
+        match self {
+            DeflateWriter { inner_writer: w } => w
+        }
+    }
+
+    fn inner_ref<'a>(&'a self) -> &'a W {
+        match *self {
+            DeflateWriter { inner_writer: ref w } => w
+        }
+    }
+
+    fn inner_mut_ref<'a>(&'a mut self) -> &'a mut W {
+        match *self {
+            DeflateWriter { inner_writer: ref mut w } => w
+        }
+    }
+}
+
+/// A Reader decorator that decompresses using the 'deflate' scheme
+pub struct InflateReader<R> {
+    inner_reader: R
+}
+
+impl<R: Reader> InflateReader<R> {
+    pub fn new(inner_reader: R) -> InflateReader<R> {
+        InflateReader {
+            inner_reader: inner_reader
+        }
+    }
+}
+
+impl<R: Reader> Reader for InflateReader<R> {
+    fn read(&mut self, _buf: &mut [u8]) -> Option<uint> { fail!() }
+
+    fn eof(&mut self) -> bool { fail!() }
+}
+
+impl<R: Reader> Decorator<R> for InflateReader<R> {
+    fn inner(self) -> R {
+        match self {
+            InflateReader { inner_reader: r } => r
+        }
+    }
+
+    fn inner_ref<'a>(&'a self) -> &'a R {
+        match *self {
+            InflateReader { inner_reader: ref r } => r
+        }
+    }
+
+    fn inner_mut_ref<'a>(&'a mut self) -> &'a mut R {
+        match *self {
+            InflateReader { inner_reader: ref mut r } => r
+        }
+    }
+}
+
+#[cfg(test)]
+mod test {
+    use prelude::*;
+    use super::*;
+    use super::super::mem::*;
+    use super::super::Decorator;
+
+    #[test]
+    #[ignore]
+    fn smoke_test() {
+        let mem_writer = MemWriter::new();
+        let mut deflate_writer = DeflateWriter::new(mem_writer);
+        let in_msg = "test";
+        let in_bytes = in_msg.to_bytes();
+        deflate_writer.write(in_bytes);
+        deflate_writer.flush();
+        let buf = deflate_writer.inner().inner();
+        let mem_reader = MemReader::new(buf);
+        let mut inflate_reader = InflateReader::new(mem_reader);
+        let mut out_bytes = [0, .. 100];
+        let bytes_read = inflate_reader.read(out_bytes).get();
+        assert!(bytes_read == in_bytes.len());
+        let out_msg = str::from_bytes(out_bytes);
+        assert!(in_msg == out_msg);
+    }
+}