std: move stdio to `sys`

As per #117276, this moves the platform definitions of `Stdout` and friends into `sys`. This PR also unifies the UNIX and Hermit implementations and moves the `__rust_print_err` function needed by libunwind on SGX into the dedicated module for such helper functions.

1 files changed, 38 insertions, 0 deletions

diff --git a/library/std/src/sys/stdio/mod.rs b/library/std/src/sys/stdio/mod.rs
new file mode 100644
index 00000000000..2a9167bfe96
--- /dev/null
+++ b/library/std/src/sys/stdio/mod.rs
@@ -0,0 +1,38 @@
+#![forbid(unsafe_op_in_unsafe_fn)]
+
+cfg_if::cfg_if! {
+    if #[cfg(any(
+        target_family = "unix",
+        target_os = "hermit"
+    ))] {
+        mod unix;
+        pub use unix::*;
+    } else if #[cfg(target_os = "windows")] {
+        mod windows;
+        pub use windows::*;
+    } else if #[cfg(all(target_vendor = "fortanix", target_env = "sgx"))] {
+        mod sgx;
+        pub use sgx::*;
+    } else if #[cfg(target_os = "solid_asp3")] {
+        mod solid;
+        pub use solid::*;
+    } else if #[cfg(target_os = "teeos")] {
+        mod teeos;
+        pub use teeos::*;
+    } else if #[cfg(target_os = "uefi")] {
+        mod uefi;
+        pub use uefi::*;
+    } else if #[cfg(target_os = "wasi")] {
+        mod wasi;
+        pub use wasi::*;
+    } else if #[cfg(target_os = "xous")] {
+        mod xous;
+        pub use xous::*;
+    } else if #[cfg(target_os = "zkvm")] {
+        mod zkvm;
+        pub use zkvm::*;
+    } else {
+        mod unsupported;
+        pub use unsupported::*;
+    }
+}