Auto merge of #23292 - alexcrichton:stabilize-io, r=aturon

The new `std::io` module has had some time to bake now, and this commit
stabilizes its functionality. There are still portions of the module which
remain unstable, and below contains a summart of the actions taken.

This commit also deprecates the entire contents of the `old_io` module in a
blanket fashion. All APIs should now have a reasonable replacement in the
new I/O modules.

Stable APIs:

* `std::io` (the name)
* `std::io::prelude` (the name)
* `Read`
* `Read::read`
* `Read::{read_to_end, read_to_string}` after being modified to return a `usize`
  for the number of bytes read.
* `ReadExt`
* `Write`
* `Write::write`
* `Write::{write_all, write_fmt}`
* `WriteExt`
* `BufRead`
* `BufRead::{fill_buf, consume}`
* `BufRead::{read_line, read_until}` after being modified to return a `usize`
  for the number of bytes read.
* `BufReadExt`
* `BufReader`
* `BufReader::{new, with_capacity}`
* `BufReader::{get_ref, get_mut, into_inner}`
* `{Read,BufRead} for BufReader`
* `BufWriter`
* `BufWriter::{new, with_capacity}`
* `BufWriter::{get_ref, get_mut, into_inner}`
* `Write for BufWriter`
* `IntoInnerError`
* `IntoInnerError::{error, into_inner}`
* `{Error,Display} for IntoInnerError`
* `LineWriter`
* `LineWriter::{new, with_capacity}` - `with_capacity` was added
* `LineWriter::{get_ref, get_mut, into_inner}` - `get_mut` was added)
* `Write for LineWriter`
* `BufStream`
* `BufStream::{new, with_capacities}`
* `BufStream::{get_ref, get_mut, into_inner}`
* `{BufRead,Read,Write} for BufStream`
* `stdin`
* `Stdin`
* `Stdin::lock`
* `Stdin::read_line` - added method
* `StdinLock`
* `Read for Stdin`
* `{Read,BufRead} for StdinLock`
* `stdout`
* `Stdout`
* `Stdout::lock`
* `StdoutLock`
* `Write for Stdout`
* `Write for StdoutLock`
* `stderr`
* `Stderr`
* `Stderr::lock`
* `StderrLock`
* `Write for Stderr`
* `Write for StderrLock`
* `io::Result`
* `io::Error`
* `io::Error::last_os_error`
* `{Display, Error} for Error`

Unstable APIs:

(reasons can be found in the commit itself)

* `Write::flush`
* `Seek`
* `ErrorKind`
* `Error::new`
* `Error::from_os_error`
* `Error::kind`

Deprecated APIs

* `Error::description` - available via the `Error` trait
* `Error::detail` - available via the `Display` implementation
* `thread::Builder::{stdout, stderr}`

Changes in functionality:

* `old_io::stdio::set_stderr` is now a noop as the infrastructure for printing
  backtraces has migrated to `std::io`.

[breaking-change]

1 files changed, 9 insertions, 0 deletions

diff --git a/src/libstd/sys/unix/mod.rs b/src/libstd/sys/unix/mod.rs
index 865ea987279..a8cee74828d 100644
--- a/src/libstd/sys/unix/mod.rs
+++ b/src/libstd/sys/unix/mod.rs
@@ -60,10 +60,12 @@ pub type wrlen = libc::size_t;
 pub type msglen_t = libc::size_t;
 pub unsafe fn close_sock(sock: sock_t) { let _ = libc::close(sock); }
 
+#[allow(deprecated)]
 pub fn last_error() -> IoError {
     decode_error_detailed(os::errno() as i32)
 }
 
+#[allow(deprecated)]
 pub fn last_net_error() -> IoError {
     last_error()
 }
@@ -72,6 +74,7 @@ extern "system" {
     fn gai_strerror(errcode: libc::c_int) -> *const libc::c_char;
 }
 
+#[allow(deprecated)]
 pub fn last_gai_error(s: libc::c_int) -> IoError {
 
     let mut err = decode_error(s);
@@ -83,6 +86,7 @@ pub fn last_gai_error(s: libc::c_int) -> IoError {
 }
 
 /// Convert an `errno` value into a high-level error variant and description.
+#[allow(deprecated)]
 pub fn decode_error(errno: i32) -> IoError {
     // FIXME: this should probably be a bit more descriptive...
     let (kind, desc) = match errno {
@@ -119,12 +123,14 @@ pub fn decode_error(errno: i32) -> IoError {
     IoError { kind: kind, desc: desc, detail: None }
 }
 
+#[allow(deprecated)]
 pub fn decode_error_detailed(errno: i32) -> IoError {
     let mut err = decode_error(errno);
     err.detail = Some(os::error_string(errno));
     err
 }
 
+#[allow(deprecated)]
 pub fn decode_error_kind(errno: i32) -> ErrorKind {
     match errno as libc::c_int {
         libc::ECONNREFUSED => ErrorKind::ConnectionRefused,
@@ -155,6 +161,7 @@ pub fn decode_error_kind(errno: i32) -> ErrorKind {
 }
 
 #[inline]
+#[allow(deprecated)]
 pub fn retry<T, F> (mut f: F) -> T where
     T: SignedInt,
     F: FnMut() -> T,
@@ -194,11 +201,13 @@ pub fn ms_to_timeval(ms: u64) -> libc::timeval {
     }
 }
 
+#[allow(deprecated)]
 pub fn wouldblock() -> bool {
     let err = os::errno();
     err == libc::EWOULDBLOCK as i32 || err == libc::EAGAIN as i32
 }
 
+#[allow(deprecated)]
 pub fn set_nonblocking(fd: sock_t, nb: bool) {
     let set = nb as libc::c_int;
     mkerr_libc(retry(|| unsafe { c::ioctl(fd, c::FIONBIO, &set) })).unwrap();