no_std building support

Cargo.toml

@@ -6,4 +6,9 @@ edition = "2018"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
+
 [dependencies]
+
+[features]
+default = ["std"]
+std = []

src/arch/mod.rs

@@ -6,8 +6,13 @@ use crate::{
     VirtualAddress,
 };
 
-pub mod emulate;
-pub mod x86_64;
+#[cfg(feature = "std")]
+pub use self::emulate::EmulateArch;
+pub use self::x86_64::X8664Arch;
+
+#[cfg(feature = "std")]
+mod emulate;
+mod x86_64;
 
 pub trait Arch {
     const PAGE_SHIFT: usize;

src/lib.rs

@@ -1,8 +1,8 @@
+#![cfg_attr(not(feature = "std"), no_std)]
 #![feature(asm)]
 
 pub use crate::{
-    arch::Arch,
-    arch::emulate::*,
+    arch::*,
     page::{
         PageEntry,
         PageTable