From 6a45b295607d0e1dd79be6a337fce543df91da8e Mon Sep 17 00:00:00 2001
From: Philipp Oppermann <dev@phil-opp.com>
Date: Tue, 12 Apr 2016 00:37:50 +0200
Subject: [PATCH] Create hole_list_allocator crate

---
 libs/hole_list_allocator/.gitignore |  2 +
 libs/hole_list_allocator/Cargo.toml |  9 +++++
 libs/hole_list_allocator/src/lib.rs | 59 +++++++++++++++++++++++++++++
 3 files changed, 70 insertions(+)
 create mode 100644 libs/hole_list_allocator/.gitignore
 create mode 100644 libs/hole_list_allocator/Cargo.toml
 create mode 100644 libs/hole_list_allocator/src/lib.rs

diff --git a/libs/hole_list_allocator/.gitignore b/libs/hole_list_allocator/.gitignore
new file mode 100644
index 00000000..49d4fed9
--- /dev/null
+++ b/libs/hole_list_allocator/.gitignore
@@ -0,0 +1,2 @@
+# Generated by Cargo
+/target/
diff --git a/libs/hole_list_allocator/Cargo.toml b/libs/hole_list_allocator/Cargo.toml
new file mode 100644
index 00000000..a055c0b9
--- /dev/null
+++ b/libs/hole_list_allocator/Cargo.toml
@@ -0,0 +1,9 @@
+[package]
+authors = ["Philipp Oppermann <dev@phil-opp.com>"]
+name = "hole_list_allocator"
+version = "0.1.0"
+
+[dependencies]
+linked_list_allocator = "0.2.0"
+spin = "0.3.5"
+once = "0.2.0"
diff --git a/libs/hole_list_allocator/src/lib.rs b/libs/hole_list_allocator/src/lib.rs
new file mode 100644
index 00000000..c6829eb2
--- /dev/null
+++ b/libs/hole_list_allocator/src/lib.rs
@@ -0,0 +1,59 @@
+#![feature(allocator)]
+#![feature(const_fn)]
+
+#![allocator]
+#![no_std]
+
+use spin::Mutex;
+use linked_list_allocator::Heap;
+
+extern crate spin;
+extern crate linked_list_allocator;
+#[macro_use]
+extern crate once;
+
+pub const HEAP_START: usize = 0o_000_001_000_000_0000;
+pub const HEAP_SIZE: usize = 100 * 1024; // 100 KiB
+
+lazy_static! {
+    static ref HEAP: Mutex<Heap> = Mutex::new(unsafe {
+        Heap::new(HEAP_START, HEAP_SIZE)
+    });
+}
+
+#[no_mangle]
+pub extern fn __rust_allocate(size: usize, align: usize) -> *mut u8 {
+    HEAP.lock().allocate_first_fit(size, align).expect("out of memory")
+}
+
+#[no_mangle]
+pub extern fn __rust_deallocate(ptr: *mut u8, size: usize, align: usize) {
+    unsafe { HEAP.lock().deallocate(ptr, size, align) };
+}
+
+#[no_mangle]
+pub extern fn __rust_usable_size(size: usize, _align: usize) -> usize {
+    size
+}
+
+#[no_mangle]
+pub extern fn __rust_reallocate_inplace(_ptr: *mut u8, size: usize,
+    _new_size: usize, _align: usize) -> usize
+{
+    size
+}
+
+#[no_mangle]
+pub extern fn __rust_reallocate(ptr: *mut u8, size: usize, new_size: usize,
+                                align: usize) -> *mut u8 {
+    use core::{ptr, cmp};
+
+    // from: https://github.com/rust-lang/rust/blob/
+    //     c66d2380a810c9a2b3dbb4f93a830b101ee49cc2/
+    //     src/liballoc_system/lib.rs#L98-L101
+
+    let new_ptr = __rust_allocate(new_size, align);
+    unsafe { ptr::copy(ptr, new_ptr, cmp::min(size, new_size)) };
+    __rust_deallocate(ptr, size, align);
+    new_ptr
+}