Auto merge of #37702 - redox-os:redox, r=brson

Redox Support Preview

# Important - This is only a preview of a working `sys::redox`.

Compiling the Redox default distribution with this `libstd` results in a fully functioning distribution. As such, all further changes would be cosmetic or implementing features that have not been used by the default distribution (of which there are only a small number).

I do not expect this to be merged, but would like to discuss how it may be improved and get feedback.

There are a few `unimplemented!()` - `cloexec` for example. I have documented them below. These would be resolved before desiring a merge.

There are also issues with how the Redox syscall library is called - currently I am using a re-export in `libc` but that probably would not be desired.

Author: bors

src/libpanic_abort/lib.rs

@@ -28,7 +28,7 @@
 #![panic_runtime]
 #![feature(panic_runtime)]
 #![cfg_attr(unix, feature(libc))]
-#![cfg_attr(windows, feature(core_intrinsics))]
+#![cfg_attr(any(target_os = "redox", windows), feature(core_intrinsics))]
 
 // Rust's "try" function, but if we're aborting on panics we just call the
 // function as there's nothing else we need to do here.
@@ -61,7 +61,7 @@ pub unsafe extern fn __rust_start_panic(_data: usize, _vtable: usize) -> u32 {
         libc::abort();
     }
 
-    #[cfg(windows)]
+    #[cfg(any(target_os = "redox", windows))]
     unsafe fn abort() -> ! {
         core::intrinsics::abort();
     }

src/libpanic_unwind/lib.rs

@@ -69,6 +69,7 @@ mod imp;
 
 // i686-pc-windows-gnu and all others
 #[cfg(any(all(unix, not(target_os = "emscripten")),
+          target_os = "redox",
           all(windows, target_arch = "x86", target_env = "gnu")))]
 #[path = "gcc.rs"]
 mod imp;

src/libstd/io/stdio.rs

@@ -81,11 +81,11 @@ impl Read for StdinRaw {
 }
 impl Write for StdoutRaw {
     fn write(&mut self, buf: &[u8]) -> io::Result<usize> { self.0.write(buf) }
-    fn flush(&mut self) -> io::Result<()> { Ok(()) }
+    fn flush(&mut self) -> io::Result<()> { self.0.flush() }
 }
 impl Write for StderrRaw {
     fn write(&mut self, buf: &[u8]) -> io::Result<usize> { self.0.write(buf) }
-    fn flush(&mut self) -> io::Result<()> { Ok(()) }
+    fn flush(&mut self) -> io::Result<()> { self.0.flush() }
 }
 
 enum Maybe<T> {

src/libstd/os/mod.rs

@@ -13,7 +13,7 @@
 #![stable(feature = "os", since = "1.0.0")]
 #![allow(missing_docs, bad_style)]
 
-#[cfg(unix)]
+#[cfg(any(target_os = "redox", unix))]
 #[stable(feature = "rust1", since = "1.0.0")]
 pub use sys::ext as unix;
 #[cfg(windows)]

src/libstd/sys/mod.rs

@@ -32,6 +32,10 @@
 
 pub use self::imp::*;
 
+#[cfg(target_os = "redox")]
+#[path = "redox/mod.rs"]
+mod imp;
+
 #[cfg(unix)]
 #[path = "unix/mod.rs"]
 mod imp;

src/libstd/sys/redox/args.rs

@@ -0,0 +1,109 @@
+// Copyright 2016 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.
+
+//! Global initialization and retreival of command line arguments.
+//!
+//! On some platforms these are stored during runtime startup,
+//! and on some they are retrieved from the system on demand.
+
+#![allow(dead_code)] // runtime init functions not used during testing
+
+use ffi::OsString;
+use marker::PhantomData;
+use vec;
+
+/// One-time global initialization.
+pub unsafe fn init(argc: isize, argv: *const *const u8) { imp::init(argc, argv) }
+
+/// One-time global cleanup.
+pub unsafe fn cleanup() { imp::cleanup() }
+
+/// Returns the command line arguments
+pub fn args() -> Args {
+    imp::args()
+}
+
+pub struct Args {
+    iter: vec::IntoIter<OsString>,
+    _dont_send_or_sync_me: PhantomData<*mut ()>,
+}
+
+impl Iterator for Args {
+    type Item = OsString;
+    fn next(&mut self) -> Option<OsString> { self.iter.next() }
+    fn size_hint(&self) -> (usize, Option<usize>) { self.iter.size_hint() }
+}
+
+impl ExactSizeIterator for Args {
+    fn len(&self) -> usize { self.iter.len() }
+}
+
+impl DoubleEndedIterator for Args {
+    fn next_back(&mut self) -> Option<OsString> { self.iter.next_back() }
+}
+
+mod imp {
+    use os::unix::prelude::*;
+    use mem;
+    use ffi::OsString;
+    use marker::PhantomData;
+    use slice;
+    use str;
+    use super::Args;
+
+    use sys_common::mutex::Mutex;
+
+    static mut GLOBAL_ARGS_PTR: usize = 0;
+    static LOCK: Mutex = Mutex::new();
+
+    pub unsafe fn init(argc: isize, argv: *const *const u8) {
+        let mut args: Vec<Vec<u8>> = Vec::new();
+        for i in 0..argc {
+            let len = *(argv.offset(i * 2)) as usize;
+            let ptr = *(argv.offset(i * 2 + 1));
+            args.push(slice::from_raw_parts(ptr, len).to_vec());
+        }
+
+        LOCK.lock();
+        let ptr = get_global_ptr();
+        assert!((*ptr).is_none());
+        (*ptr) = Some(box args);
+        LOCK.unlock();
+    }
+
+    pub unsafe fn cleanup() {
+        LOCK.lock();
+        *get_global_ptr() = None;
+        LOCK.unlock();
+    }
+
+    pub fn args() -> Args {
+        let bytes = clone().unwrap_or(Vec::new());
+        let v: Vec<OsString> = bytes.into_iter().map(|v| {
+            OsStringExt::from_vec(v)
+        }).collect();
+        Args { iter: v.into_iter(), _dont_send_or_sync_me: PhantomData }
+    }
+
+    fn clone() -> Option<Vec<Vec<u8>>> {
+        unsafe {
+            LOCK.lock();
+            let ptr = get_global_ptr();
+            let ret = (*ptr).as_ref().map(|s| (**s).clone());
+            LOCK.unlock();
+            return ret
+        }
+    }
+
+    fn get_global_ptr() -> *mut Option<Box<Vec<Vec<u8>>>> {
+        unsafe { mem::transmute(&GLOBAL_ARGS_PTR) }
+    }
+
+}

src/libstd/sys/redox/backtrace.rs

@@ -0,0 +1,18 @@
+// Copyright 2016 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 libc;
+use io;
+use sys_common::backtrace::output;
+
+#[inline(never)]
+pub fn write(w: &mut io::Write) -> io::Result<()> {
+    output(w, 0, 0 as *mut libc::c_void, None)
+}

src/libstd/sys/redox/condvar.rs

@@ -0,0 +1,106 @@
+// Copyright 2016 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 cell::UnsafeCell;
+use intrinsics::{atomic_cxchg, atomic_xadd, atomic_xchg};
+use ptr;
+use time::Duration;
+
+use sys::mutex::{mutex_lock, mutex_unlock, Mutex};
+use sys::syscall::{futex, FUTEX_WAIT, FUTEX_WAKE, FUTEX_REQUEUE};
+
+pub struct Condvar {
+    lock: UnsafeCell<*mut i32>,
+    seq: UnsafeCell<i32>
+}
+
+impl Condvar {
+    pub const fn new() -> Condvar {
+        Condvar {
+            lock: UnsafeCell::new(ptr::null_mut()),
+            seq: UnsafeCell::new(0)
+        }
+    }
+
+    #[inline]
+    pub unsafe fn init(&self) {
+        *self.lock.get() = ptr::null_mut();
+        *self.seq.get() = 0;
+    }
+
+    #[inline]
+    pub fn notify_one(&self) {
+        unsafe {
+            let seq = self.seq.get();
+
+            atomic_xadd(seq, 1);
+
+            let _ = futex(seq, FUTEX_WAKE, 1, 0, ptr::null_mut());
+        }
+    }
+
+    #[inline]
+    pub fn notify_all(&self) {
+        unsafe {
+            let lock = self.lock.get();
+            let seq = self.seq.get();
+
+            if *lock == ptr::null_mut() {
+                return;
+            }
+
+            atomic_xadd(seq, 1);
+
+            let _ = futex(seq, FUTEX_REQUEUE, 1, ::usize::MAX, *lock);
+        }
+    }
+
+    #[inline]
+    pub fn wait(&self, mutex: &Mutex) {
+        unsafe {
+            let lock = self.lock.get();
+            let seq = self.seq.get();
+
+            if *lock != mutex.lock.get() {
+                if *lock != ptr::null_mut() {
+                    panic!("Condvar used with more than one Mutex");
+                }
+
+                atomic_cxchg(lock as *mut usize, 0, mutex.lock.get() as usize);
+            }
+
+            mutex_unlock(*lock);
+
+            let _ = futex(seq, FUTEX_WAIT, *seq, 0, ptr::null_mut());
+
+            while atomic_xchg(*lock, 2) != 0 {
+                let _ = futex(*lock, FUTEX_WAIT, 2, 0, ptr::null_mut());
+            }
+
+            mutex_lock(*lock);
+        }
+    }
+
+    #[inline]
+    pub fn wait_timeout(&self, _mutex: &Mutex, _dur: Duration) -> bool {
+        ::sys_common::util::dumb_print(format_args!("condvar wait_timeout\n"));
+        unimplemented!();
+    }
+
+    #[inline]
+    pub unsafe fn destroy(&self) {
+        *self.lock.get() = ptr::null_mut();
+        *self.seq.get() = 0;
+    }
+}
+
+unsafe impl Send for Condvar {}
+
+unsafe impl Sync for Condvar {}

src/libstd/sys/redox/env.rs

@@ -0,0 +1,19 @@
+// Copyright 2016 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.
+
+pub mod os {
+    pub const FAMILY: &'static str = "redox";
+    pub const OS: &'static str = "redox";
+    pub const DLL_PREFIX: &'static str = "lib";
+    pub const DLL_SUFFIX: &'static str = ".so";
+    pub const DLL_EXTENSION: &'static str = "so";
+    pub const EXE_SUFFIX: &'static str = "";
+    pub const EXE_EXTENSION: &'static str = "";
+}

src/libstd/sys/redox/ext/ffi.rs

@@ -0,0 +1,61 @@
+// Copyright 2015 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.
+
+//! Unix-specific extension to the primitives in the `std::ffi` module
+
+#![stable(feature = "rust1", since = "1.0.0")]
+
+use ffi::{OsStr, OsString};
+use mem;
+use sys::os_str::Buf;
+use sys_common::{FromInner, IntoInner, AsInner};
+
+/// Unix-specific extensions to `OsString`.
+#[stable(feature = "rust1", since = "1.0.0")]
+pub trait OsStringExt {
+    /// Creates an `OsString` from a byte vector.
+    #[stable(feature = "rust1", since = "1.0.0")]
+    fn from_vec(vec: Vec<u8>) -> Self;
+
+    /// Yields the underlying byte vector of this `OsString`.
+    #[stable(feature = "rust1", since = "1.0.0")]
+    fn into_vec(self) -> Vec<u8>;
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl OsStringExt for OsString {
+    fn from_vec(vec: Vec<u8>) -> OsString {
+        FromInner::from_inner(Buf { inner: vec })
+    }
+    fn into_vec(self) -> Vec<u8> {
+        self.into_inner().inner
+    }
+}
+
+/// Unix-specific extensions to `OsStr`.
+#[stable(feature = "rust1", since = "1.0.0")]
+pub trait OsStrExt {
+    #[stable(feature = "rust1", since = "1.0.0")]
+    fn from_bytes(slice: &[u8]) -> &Self;
+
+    /// Gets the underlying byte view of the `OsStr` slice.
+    #[stable(feature = "rust1", since = "1.0.0")]
+    fn as_bytes(&self) -> &[u8];
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl OsStrExt for OsStr {
+    fn from_bytes(slice: &[u8]) -> &OsStr {
+        unsafe { mem::transmute(slice) }
+    }
+    fn as_bytes(&self) -> &[u8] {
+        &self.as_inner().inner
+    }
+}