std: begin moving platform support modules into `pal`

1 files changed, 0 insertions, 81 deletions

diff --git a/library/std/src/sys/unix/android.rs b/library/std/src/sys/unix/android.rs
deleted file mode 100644
index 0f704994f55..00000000000
--- a/library/std/src/sys/unix/android.rs
+++ /dev/null
@@ -1,81 +0,0 @@
-//! Android ABI-compatibility module
-//!
-//! The ABI of Android has changed quite a bit over time, and std 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, sighandler_t};
-
-use super::weak::weak;
-
-// 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() * crate::f32::consts::LOG2_E
-}
-
-#[cfg(not(test))]
-pub fn log2f64(f: f64) -> f64 {
-    f.ln() * crate::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)
-}