std: Funnel read_to_end through to one location

This pushes the implementation detail of proxying `read_to_end` through to
`read_to_end_uninitialized` all the way down to the `FileDesc` and `Handle`
implementations on Unix/Windows. This way intermediate layers will also be able
to take advantage of this optimized implementation.

This commit also adds the optimized implementation for `ChildStdout` and
`ChildStderr`.

15 files changed, 136 insertions, 11 deletions

diff --git a/src/libstd/fs.rs b/src/libstd/fs.rs
index 53384fb9b15..6b88d498b10 100644
--- a/src/libstd/fs.rs
+++ b/src/libstd/fs.rs
@@ -22,7 +22,6 @@ use ffi::OsString;
 use io::{self, SeekFrom, Seek, Read, Write};
 use path::{Path, PathBuf};
 use sys::fs as fs_imp;
-use sys_common::io::read_to_end_uninitialized;
 use sys_common::{AsInnerMut, FromInner, AsInner, IntoInner};
 use vec::Vec;
 use time::SystemTime;
@@ -351,7 +350,7 @@ impl Read for File {
         self.inner.read(buf)
     }
     fn read_to_end(&mut self, buf: &mut Vec<u8>) -> io::Result<usize> {
-        unsafe { read_to_end_uninitialized(self, buf) }
+        self.inner.read_to_end(buf)
     }
 }
 #[stable(feature = "rust1", since = "1.0.0")]
@@ -372,6 +371,9 @@ impl<'a> Read for &'a File {
     fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
         self.inner.read(buf)
     }
+    fn read_to_end(&mut self, buf: &mut Vec<u8>) -> io::Result<usize> {
+        self.inner.read_to_end(buf)
+    }
 }
 #[stable(feature = "rust1", since = "1.0.0")]
 impl<'a> Write for &'a File {
diff --git a/src/libstd/io/stdio.rs b/src/libstd/io/stdio.rs
index cd2d5e52462..25309a785c4 100644
--- a/src/libstd/io/stdio.rs
+++ b/src/libstd/io/stdio.rs
@@ -18,7 +18,6 @@ use io::lazy::Lazy;
 use io::{self, BufReader, LineWriter};
 use sync::{Arc, Mutex, MutexGuard};
 use sys::stdio;
-use sys_common::io::{read_to_end_uninitialized};
 use sys_common::remutex::{ReentrantMutex, ReentrantMutexGuard};
 use thread::LocalKeyState;
 
@@ -78,6 +77,9 @@ fn stderr_raw() -> io::Result<StderrRaw> { stdio::Stderr::new().map(StderrRaw) }
 
 impl Read for StdinRaw {
     fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> { self.0.read(buf) }
+    fn read_to_end(&mut self, buf: &mut Vec<u8>) -> io::Result<usize> {
+        self.0.read_to_end(buf)
+    }
 }
 impl Write for StdoutRaw {
     fn write(&mut self, buf: &[u8]) -> io::Result<usize> { self.0.write(buf) }
@@ -116,6 +118,12 @@ impl<R: io::Read> io::Read for Maybe<R> {
             Maybe::Fake => Ok(0)
         }
     }
+    fn read_to_end(&mut self, buf: &mut Vec<u8>) -> io::Result<usize> {
+        match *self {
+            Maybe::Real(ref mut r) => handle_ebadf(r.read_to_end(buf), 0),
+            Maybe::Fake => Ok(0)
+        }
+    }
 }
 
 fn handle_ebadf<T>(r: io::Result<T>, default: T) -> io::Result<T> {
@@ -294,7 +302,7 @@ impl<'a> Read for StdinLock<'a> {
         self.inner.read(buf)
     }
     fn read_to_end(&mut self, buf: &mut Vec<u8>) -> io::Result<usize> {
-        unsafe { read_to_end_uninitialized(self, buf) }
+        self.inner.read_to_end(buf)
     }
 }
 
diff --git a/src/libstd/net/tcp.rs b/src/libstd/net/tcp.rs
index f8e3b58bb3e..414696413f4 100644
--- a/src/libstd/net/tcp.rs
+++ b/src/libstd/net/tcp.rs
@@ -14,7 +14,6 @@ use io::prelude::*;
 use fmt;
 use io;
 use net::{ToSocketAddrs, SocketAddr, Shutdown};
-use sys_common::io::read_to_end_uninitialized;
 use sys_common::net as net_imp;
 use sys_common::{AsInner, FromInner, IntoInner};
 use time::Duration;
@@ -269,7 +268,7 @@ impl TcpStream {
 impl Read for TcpStream {
     fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> { self.0.read(buf) }
     fn read_to_end(&mut self, buf: &mut Vec<u8>) -> io::Result<usize> {
-        unsafe { read_to_end_uninitialized(self, buf) }
+        self.0.read_to_end(buf)
     }
 }
 #[stable(feature = "rust1", since = "1.0.0")]
@@ -281,7 +280,7 @@ impl Write for TcpStream {
 impl<'a> Read for &'a TcpStream {
     fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> { self.0.read(buf) }
     fn read_to_end(&mut self, buf: &mut Vec<u8>) -> io::Result<usize> {
-        unsafe { read_to_end_uninitialized(self, buf) }
+        self.0.read_to_end(buf)
     }
 }
 #[stable(feature = "rust1", since = "1.0.0")]
diff --git a/src/libstd/process.rs b/src/libstd/process.rs
index 8db8ad324be..ec86dd062b5 100644
--- a/src/libstd/process.rs
+++ b/src/libstd/process.rs
@@ -134,6 +134,9 @@ impl Read for ChildStdout {
     fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
         self.inner.read(buf)
     }
+    fn read_to_end(&mut self, buf: &mut Vec<u8>) -> io::Result<usize> {
+        self.inner.read_to_end(buf)
+    }
 }
 
 impl AsInner<AnonPipe> for ChildStdout {
@@ -161,6 +164,9 @@ impl Read for ChildStderr {
     fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
         self.inner.read(buf)
     }
+    fn read_to_end(&mut self, buf: &mut Vec<u8>) -> io::Result<usize> {
+        self.inner.read_to_end(buf)
+    }
 }
 
 impl AsInner<AnonPipe> for ChildStderr {
diff --git a/src/libstd/sys/common/net.rs b/src/libstd/sys/common/net.rs
index ca4f6e19882..aa92e5be114 100644
--- a/src/libstd/sys/common/net.rs
+++ b/src/libstd/sys/common/net.rs
@@ -225,6 +225,10 @@ impl TcpStream {
         self.inner.read(buf)
     }
 
+    pub fn read_to_end(&self, buf: &mut Vec<u8>) -> io::Result<usize> {
+        self.inner.read_to_end(buf)
+    }
+
     pub fn write(&self, buf: &[u8]) -> io::Result<usize> {
         let len = cmp::min(buf.len(), <wrlen_t>::max_value() as usize) as wrlen_t;
         let ret = try!(cvt(unsafe {
diff --git a/src/libstd/sys/unix/fd.rs b/src/libstd/sys/unix/fd.rs
index 299c6ec2731..a00e6c3eb72 100644
--- a/src/libstd/sys/unix/fd.rs
+++ b/src/libstd/sys/unix/fd.rs
@@ -8,12 +8,15 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-use io;
+use prelude::v1::*;
+
+use io::{self, Read};
 use libc::{self, c_int, size_t, c_void};
 use mem;
+use sync::atomic::{AtomicBool, Ordering};
 use sys::cvt;
 use sys_common::AsInner;
-use sync::atomic::{AtomicBool, Ordering};
+use sys_common::io::read_to_end_uninitialized;
 
 pub struct FileDesc {
     fd: c_int,
@@ -42,6 +45,11 @@ impl FileDesc {
         Ok(ret as usize)
     }
 
+    pub fn read_to_end(&self, buf: &mut Vec<u8>) -> io::Result<usize> {
+        let mut me = self;
+        (&mut me).read_to_end(buf)
+    }
+
     pub fn write(&self, buf: &[u8]) -> io::Result<usize> {
         let ret = try!(cvt(unsafe {
             libc::write(self.fd,
@@ -118,6 +126,17 @@ impl FileDesc {
     }
 }
 
+#[unstable(reason = "not public", issue = "0", feature = "fd_read")]
+impl<'a> Read for &'a FileDesc {
+    fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
+        (**self).read(buf)
+    }
+
+    fn read_to_end(&mut self, buf: &mut Vec<u8>) -> io::Result<usize> {
+        unsafe { read_to_end_uninitialized(self, buf) }
+    }
+}
+
 impl AsInner<c_int> for FileDesc {
     fn as_inner(&self) -> &c_int { &self.fd }
 }
diff --git a/src/libstd/sys/unix/fs.rs b/src/libstd/sys/unix/fs.rs
index d1b4b1c5c08..3985a07470e 100644
--- a/src/libstd/sys/unix/fs.rs
+++ b/src/libstd/sys/unix/fs.rs
@@ -486,6 +486,10 @@ impl File {
         self.0.read(buf)
     }
 
+    pub fn read_to_end(&self, buf: &mut Vec<u8>) -> io::Result<usize> {
+        self.0.read_to_end(buf)
+    }
+
     pub fn write(&self, buf: &[u8]) -> io::Result<usize> {
         self.0.write(buf)
     }
diff --git a/src/libstd/sys/unix/net.rs b/src/libstd/sys/unix/net.rs
index 8785da51986..acf501d5fda 100644
--- a/src/libstd/sys/unix/net.rs
+++ b/src/libstd/sys/unix/net.rs
@@ -116,6 +116,10 @@ impl Socket {
         self.0.read(buf)
     }
 
+    pub fn read_to_end(&self, buf: &mut Vec<u8>) -> io::Result<usize> {
+        self.0.read_to_end(buf)
+    }
+
     pub fn set_timeout(&self, dur: Option<Duration>, kind: libc::c_int) -> io::Result<()> {
         let timeout = match dur {
             Some(dur) => {
diff --git a/src/libstd/sys/unix/pipe.rs b/src/libstd/sys/unix/pipe.rs
index 667f0f9e6bf..d88193e6227 100644
--- a/src/libstd/sys/unix/pipe.rs
+++ b/src/libstd/sys/unix/pipe.rs
@@ -57,6 +57,10 @@ impl AnonPipe {
         self.0.read(buf)
     }
 
+    pub fn read_to_end(&self, buf: &mut Vec<u8>) -> io::Result<usize> {
+        self.0.read_to_end(buf)
+    }
+
     pub fn write(&self, buf: &[u8]) -> io::Result<usize> {
         self.0.write(buf)
     }
diff --git a/src/libstd/sys/unix/stdio.rs b/src/libstd/sys/unix/stdio.rs
index ccbb14677c7..37d1d9a969e 100644
--- a/src/libstd/sys/unix/stdio.rs
+++ b/src/libstd/sys/unix/stdio.rs
@@ -8,6 +8,8 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+use prelude::v1::*;
+
 use io;
 use libc;
 use sys::fd::FileDesc;
@@ -25,6 +27,13 @@ impl Stdin {
         fd.into_raw();
         ret
     }
+
+    pub fn read_to_end(&self, buf: &mut Vec<u8>) -> io::Result<usize> {
+        let fd = FileDesc::new(libc::STDIN_FILENO);
+        let ret = fd.read_to_end(buf);
+        fd.into_raw();
+        ret
+    }
 }
 
 impl Stdout {
diff --git a/src/libstd/sys/windows/fs.rs b/src/libstd/sys/windows/fs.rs
index 95fb1e7c600..624fef097fc 100644
--- a/src/libstd/sys/windows/fs.rs
+++ b/src/libstd/sys/windows/fs.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+use prelude::v1::*;
 use io::prelude::*;
 use os::windows::prelude::*;
 
@@ -312,6 +313,10 @@ impl File {
         self.handle.read(buf)
     }
 
+    pub fn read_to_end(&self, buf: &mut Vec<u8>) -> io::Result<usize> {
+        self.handle.read_to_end(buf)
+    }
+
     pub fn write(&self, buf: &[u8]) -> io::Result<usize> {
         self.handle.write(buf)
     }
diff --git a/src/libstd/sys/windows/handle.rs b/src/libstd/sys/windows/handle.rs
index 47676a927f6..f4b8b2754c5 100644
--- a/src/libstd/sys/windows/handle.rs
+++ b/src/libstd/sys/windows/handle.rs
@@ -8,14 +8,17 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+use prelude::v1::*;
+
 use cmp;
-use io::ErrorKind;
+use io::{ErrorKind, Read};
 use io;
 use mem;
 use ops::Deref;
 use ptr;
 use sys::c;
 use sys::cvt;
+use sys_common::io::read_to_end_uninitialized;
 use u32;
 
 /// An owned container for `HANDLE` object, closing them on Drop.
@@ -87,6 +90,11 @@ impl RawHandle {
         }
     }
 
+    pub fn read_to_end(&self, buf: &mut Vec<u8>) -> io::Result<usize> {
+        let mut me = self;
+        (&mut me).read_to_end(buf)
+    }
+
     pub fn write(&self, buf: &[u8]) -> io::Result<usize> {
         let mut amt = 0;
         // WriteFile takes a DWORD (u32) for the length so it only supports
@@ -111,3 +119,14 @@ impl RawHandle {
         Ok(Handle::new(ret))
     }
 }
+
+#[unstable(reason = "not public", issue = "0", feature = "fd_read")]
+impl<'a> Read for &'a RawHandle {
+    fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
+        (**self).read(buf)
+    }
+
+    fn read_to_end(&mut self, buf: &mut Vec<u8>) -> io::Result<usize> {
+        unsafe { read_to_end_uninitialized(self, buf) }
+    }
+}
diff --git a/src/libstd/sys/windows/net.rs b/src/libstd/sys/windows/net.rs
index dfa44a651e6..01e3a6cd8ed 100644
--- a/src/libstd/sys/windows/net.rs
+++ b/src/libstd/sys/windows/net.rs
@@ -8,8 +8,10 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+use prelude::v1::*;
+
 use cmp;
-use io;
+use io::{self, Read};
 use libc::{c_int, c_void, c_ulong};
 use mem;
 use net::{SocketAddr, Shutdown};
@@ -20,6 +22,7 @@ use sync::Once;
 use sys::c;
 use sys;
 use sys_common::{self, AsInner, FromInner, IntoInner};
+use sys_common::io::read_to_end_uninitialized;
 use sys_common::net;
 use time::Duration;
 
@@ -142,6 +145,11 @@ impl Socket {
         }
     }
 
+    pub fn read_to_end(&self, buf: &mut Vec<u8>) -> io::Result<usize> {
+        let mut me = self;
+        (&mut me).read_to_end(buf)
+    }
+
     pub fn set_timeout(&self, dur: Option<Duration>,
                        kind: c_int) -> io::Result<()> {
         let timeout = match dur {
@@ -206,6 +214,17 @@ impl Socket {
     }
 }
 
+#[unstable(reason = "not public", issue = "0", feature = "fd_read")]
+impl<'a> Read for &'a Socket {
+    fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
+        (**self).read(buf)
+    }
+
+    fn read_to_end(&mut self, buf: &mut Vec<u8>) -> io::Result<usize> {
+        unsafe { read_to_end_uninitialized(self, buf) }
+    }
+}
+
 impl Drop for Socket {
     fn drop(&mut self) {
         let _ = unsafe { c::closesocket(self.0) };
diff --git a/src/libstd/sys/windows/pipe.rs b/src/libstd/sys/windows/pipe.rs
index aec41885f3b..8c3171d2470 100644
--- a/src/libstd/sys/windows/pipe.rs
+++ b/src/libstd/sys/windows/pipe.rs
@@ -8,6 +8,8 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+use prelude::v1::*;
+
 use io;
 use ptr;
 use sys::cvt;
@@ -41,6 +43,10 @@ impl AnonPipe {
         self.inner.read(buf)
     }
 
+    pub fn read_to_end(&self, buf: &mut Vec<u8>) -> io::Result<usize> {
+        self.inner.read_to_end(buf)
+    }
+
     pub fn write(&self, buf: &[u8]) -> io::Result<usize> {
         self.inner.write(buf)
     }
diff --git a/src/libstd/sys/windows/stdio.rs b/src/libstd/sys/windows/stdio.rs
index 1cd05b61d25..5a8705bf0cb 100644
--- a/src/libstd/sys/windows/stdio.rs
+++ b/src/libstd/sys/windows/stdio.rs
@@ -18,6 +18,7 @@ use sync::Mutex;
 use sys::c;
 use sys::cvt;
 use sys::handle::Handle;
+use sys_common::io::read_to_end_uninitialized;
 
 pub struct NoClose(Option<Handle>);
 
@@ -113,6 +114,22 @@ impl Stdin {
         // MemReader shouldn't error here since we just filled it
         utf8.read(buf)
     }
+
+    pub fn read_to_end(&self, buf: &mut Vec<u8>) -> io::Result<usize> {
+        let mut me = self;
+        (&mut me).read_to_end(buf)
+    }
+}
+
+#[unstable(reason = "not public", issue = "0", feature = "fd_read")]
+impl<'a> Read for &'a Stdin {
+    fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
+        (**self).read(buf)
+    }
+
+    fn read_to_end(&mut self, buf: &mut Vec<u8>) -> io::Result<usize> {
+        unsafe { read_to_end_uninitialized(self, buf) }
+    }
 }
 
 impl Stdout {