Update for latest nightly 2018-06-09 (#70)

* Update for latest nightly 2018-06-09
* We now have a proper horizon os and sys modules in libstd

1 files changed, 170 insertions, 0 deletions

diff --git a/ctr-std/src/sys/horizon/android.rs b/ctr-std/src/sys/horizon/android.rs
new file mode 100644
index 0000000..1043672
--- /dev/null
+++ b/ctr-std/src/sys/horizon/android.rs
@@ -0,0 +1,170 @@
+// 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.
+
+//! Android ABI-compatibility module
+//!
+//! The ABI of Android has changed quite a bit over time, and libstd attempts to
+//! be both forwards and backwards compatible as much as possible. We want to
+//! always work with the most recent version of Android, but we also want to
+//! work with older versions of Android for whenever projects need to.
+//!
+//! Our current minimum supported Android version is `android-9`, e.g. Android
+//! with API level 9. We then in theory want to work on that and all future
+//! versions of Android!
+//!
+//! Some of the detection here is done at runtime via `dlopen` and
+//! introspection. Other times no detection is performed at all and we just
+//! provide a fallback implementation as some versions of Android we support
+//! don't have the function.
+//!
+//! You'll find more details below about why each compatibility shim is needed.
+
+#![cfg(target_os = "android")]
+
+use libc::{c_int, c_void, sighandler_t, size_t, ssize_t};
+use libc::{ftruncate, pread, pwrite};
+
+use io;
+use super::{cvt, cvt_r};
+
+// The `log2` and `log2f` functions apparently appeared in android-18, or at
+// least you can see they're not present in the android-17 header [1] and they
+// are present in android-18 [2].
+//
+// [1]: https://chromium.googlesource.com/android_tools/+/20ee6d20/ndk/platforms
+//                                       /android-17/arch-arm/usr/include/math.h
+// [2]: https://chromium.googlesource.com/android_tools/+/20ee6d20/ndk/platforms
+//                                       /android-18/arch-arm/usr/include/math.h
+//
+// Note that these shims are likely less precise than directly calling `log2`,
+// but hopefully that should be enough for now...
+//
+// Note that mathematically, for any arbitrary `y`:
+//
+//      log_2(x) = log_y(x) / log_y(2)
+//               = log_y(x) / (1 / log_2(y))
+//               = log_y(x) * log_2(y)
+//
+// Hence because `ln` (log_e) is available on all Android we just choose `y = e`
+// and get:
+//
+//      log_2(x) = ln(x) * log_2(e)
+
+#[cfg(not(test))]
+pub fn log2f32(f: f32) -> f32 {
+    f.ln() * ::f32::consts::LOG2_E
+}
+
+#[cfg(not(test))]
+pub fn log2f64(f: f64) -> f64 {
+    f.ln() * ::f64::consts::LOG2_E
+}
+
+// Back in the day [1] the `signal` function was just an inline wrapper
+// around `bsd_signal`, but starting in API level android-20 the `signal`
+// symbols was introduced [2]. Finally, in android-21 the API `bsd_signal` was
+// removed [3].
+//
+// Basically this means that if we want to be binary compatible with multiple
+// Android releases (oldest being 9 and newest being 21) then we need to check
+// for both symbols and not actually link against either.
+//
+// [1]: https://chromium.googlesource.com/android_tools/+/20ee6d20/ndk/platforms
+//                                       /android-18/arch-arm/usr/include/signal.h
+// [2]: https://chromium.googlesource.com/android_tools/+/fbd420/ndk_experimental
+//                                       /platforms/android-20/arch-arm
+//                                       /usr/include/signal.h
+// [3]: https://chromium.googlesource.com/android_tools/+/20ee6d/ndk/platforms
+//                                       /android-21/arch-arm/usr/include/signal.h
+pub unsafe fn signal(signum: c_int, handler: sighandler_t) -> sighandler_t {
+    weak!(fn signal(c_int, sighandler_t) -> sighandler_t);
+    weak!(fn bsd_signal(c_int, sighandler_t) -> sighandler_t);
+
+    let f = signal.get().or_else(|| bsd_signal.get());
+    let f = f.expect("neither `signal` nor `bsd_signal` symbols found");
+    f(signum, handler)
+}
+
+// The `ftruncate64` symbol apparently appeared in android-12, so we do some
+// dynamic detection to see if we can figure out whether `ftruncate64` exists.
+//
+// If it doesn't we just fall back to `ftruncate`, generating an error for
+// too-large values.
+#[cfg(target_pointer_width = "32")]
+pub fn ftruncate64(fd: c_int, size: u64) -> io::Result<()> {
+    weak!(fn ftruncate64(c_int, i64) -> c_int);
+
+    unsafe {
+        match ftruncate64.get() {
+            Some(f) => cvt_r(|| f(fd, size as i64)).map(|_| ()),
+            None => {
+                if size > i32::max_value() as u64 {
+                    Err(io::Error::new(io::ErrorKind::InvalidInput,
+                                       "cannot truncate >2GB"))
+                } else {
+                    cvt_r(|| ftruncate(fd, size as i32)).map(|_| ())
+                }
+            }
+        }
+    }
+}
+
+#[cfg(target_pointer_width = "64")]
+pub fn ftruncate64(fd: c_int, size: u64) -> io::Result<()> {
+    unsafe {
+        cvt_r(|| ftruncate(fd, size as i64)).map(|_| ())
+    }
+}
+
+#[cfg(target_pointer_width = "32")]
+pub unsafe fn cvt_pread64(fd: c_int, buf: *mut c_void, count: size_t, offset: i64)
+    -> io::Result<ssize_t>
+{
+    use convert::TryInto;
+    weak!(fn pread64(c_int, *mut c_void, size_t, i64) -> ssize_t);
+    pread64.get().map(|f| cvt(f(fd, buf, count, offset))).unwrap_or_else(|| {
+        if let Ok(o) = offset.try_into() {
+            cvt(pread(fd, buf, count, o))
+        } else {
+            Err(io::Error::new(io::ErrorKind::InvalidInput,
+                               "cannot pread >2GB"))
+        }
+    })
+}
+
+#[cfg(target_pointer_width = "32")]
+pub unsafe fn cvt_pwrite64(fd: c_int, buf: *const c_void, count: size_t, offset: i64)
+    -> io::Result<ssize_t>
+{
+    use convert::TryInto;
+    weak!(fn pwrite64(c_int, *const c_void, size_t, i64) -> ssize_t);
+    pwrite64.get().map(|f| cvt(f(fd, buf, count, offset))).unwrap_or_else(|| {
+        if let Ok(o) = offset.try_into() {
+            cvt(pwrite(fd, buf, count, o))
+        } else {
+            Err(io::Error::new(io::ErrorKind::InvalidInput,
+                               "cannot pwrite >2GB"))
+        }
+    })
+}
+
+#[cfg(target_pointer_width = "64")]
+pub unsafe fn cvt_pread64(fd: c_int, buf: *mut c_void, count: size_t, offset: i64)
+    -> io::Result<ssize_t>
+{
+    cvt(pread(fd, buf, count, offset))
+}
+
+#[cfg(target_pointer_width = "64")]
+pub unsafe fn cvt_pwrite64(fd: c_int, buf: *const c_void, count: size_t, offset: i64)
+    -> io::Result<ssize_t>
+{
+    cvt(pwrite(fd, buf, count, offset))
+}