Vendor dependencies for 0.3.0 release

vendor/errno/src/sys.rs

@@ -0,0 +1,35 @@
+//! A default sys.rs for unrecognized targets.
+//!
+//! If lib.rs doesn't recognize the target, it defaults to using this file,
+//! which issues an explanatory compile error.
+
+// If there is no OS, there's no `errno` or equivalent defined.
+#[cfg(any(target_os = "unknown", target_os = "none"))]
+compile_error!("The target OS is \"unknown\" or \"none\", so it's unsupported by the errno crate.");
+
+// If there is an OS, support may be added.
+#[cfg(not(any(target_os = "unknown", target_os = "none")))]
+compile_error!("The target OS is not yet supported in the errno crate.");
+
+// The following define the functions of the normal implementations
+// so that the user doesn't see uninteresting errors after the
+// errors above.
+
+use crate::Errno;
+
+pub fn with_description<F, T>(_err: Errno, _callback: F) -> T
+where
+    F: FnOnce(Result<&str, Errno>) -> T,
+{
+    unreachable!()
+}
+
+pub const STRERROR_NAME: &str = "";
+
+pub fn errno() -> Errno {
+    unreachable!()
+}
+
+pub fn set_errno(_: Errno) {
+    unreachable!()
+}