From 7b623e0fdf8b389502542eb26abe6298885fa099 Mon Sep 17 00:00:00 2001
From: Avril <flanchan@cumallover.me>
Date: Sat, 12 Jun 2021 00:48:43 +0100
Subject: [PATCH] rust bindings: start

---
 .gitignore          |  2 ++
 cowslice/Cargo.lock | 34 ++++++++++++++++++++++++++++++++++
 cowslice/Cargo.toml | 11 +++++++++++
 cowslice/build.rs   | 27 +++++++++++++++++++++++++++
 cowslice/src/ffi.rs | 29 +++++++++++++++++++++++++++++
 cowslice/src/lib.rs | 25 +++++++++++++++++++++++++
 6 files changed, 128 insertions(+)
 create mode 100644 cowslice/Cargo.lock
 create mode 100644 cowslice/Cargo.toml
 create mode 100644 cowslice/build.rs
 create mode 100644 cowslice/src/ffi.rs
 create mode 100644 cowslice/src/lib.rs

diff --git a/.gitignore b/.gitignore
index 036690b..c2afdd8 100644
--- a/.gitignore
+++ b/.gitignore
@@ -4,3 +4,5 @@ cow-*
 obj/
 *~
 vgcore.*
+target/
+!cowslice/*.a
diff --git a/cowslice/Cargo.lock b/cowslice/Cargo.lock
new file mode 100644
index 0000000..8534f00
--- /dev/null
+++ b/cowslice/Cargo.lock
@@ -0,0 +1,34 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 3
+
+[[package]]
+name = "cowslice"
+version = "0.1.0"
+dependencies = [
+ "rustc_version",
+]
+
+[[package]]
+name = "rustc_version"
+version = "0.2.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "138e3e0acb6c9fb258b19b67cb8abd63c00679d2851805ea151465464fe9030a"
+dependencies = [
+ "semver",
+]
+
+[[package]]
+name = "semver"
+version = "0.9.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1d7eb9ef2c18661902cc47e535f9bc51b78acd254da71d375c2f6720d9a40403"
+dependencies = [
+ "semver-parser",
+]
+
+[[package]]
+name = "semver-parser"
+version = "0.7.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "388a1df253eca08550bef6c72392cfe7c30914bf41df5269b68cbd6ff8f570a3"
diff --git a/cowslice/Cargo.toml b/cowslice/Cargo.toml
new file mode 100644
index 0000000..423fbbd
--- /dev/null
+++ b/cowslice/Cargo.toml
@@ -0,0 +1,11 @@
+[package]
+name = "cowslice"
+version = "0.1.0"
+edition = "2018"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+
+[build-dependencies]
+rustc_version = "0.2"
diff --git a/cowslice/build.rs b/cowslice/build.rs
new file mode 100644
index 0000000..ff8ed17
--- /dev/null
+++ b/cowslice/build.rs
@@ -0,0 +1,27 @@
+
+extern crate rustc_version;
+use rustc_version::{version, version_meta, Channel};
+
+fn main() {
+    // Assert we haven't travelled back in time
+    assert!(version().unwrap().major >= 1);
+
+    // Set cfg flags depending on release channel
+    match version_meta().unwrap().channel {
+        Channel::Stable => {
+            println!("cargo:rustc-cfg=stable");
+        }
+        Channel::Beta => {
+            println!("cargo:rustc-cfg=beta");
+        }
+        Channel::Nightly => {
+            println!("cargo:rustc-cfg=nightly");
+        }
+        Channel::Dev => {
+            println!("cargo:rustc-cfg=dev");
+        }
+    }
+    // Link to `libcow.a`
+    println!(r"cargo:rustc-link-search=./lib");
+    println!(r"cargo:rustc-link-lib=cow");
+}
diff --git a/cowslice/src/ffi.rs b/cowslice/src/ffi.rs
new file mode 100644
index 0000000..cba37ef
--- /dev/null
+++ b/cowslice/src/ffi.rs
@@ -0,0 +1,29 @@
+//! Interfaces with the C library
+use core::ffi::c_void;
+
+/// Raw `cow_t*`
+///
+/// This is, essentially, a pointer to the origin (`void*`) pointer.
+/// So is represented as `*mut RawHandle == void**`.
+pub type RawHandle = *mut c_void;
+
+extern "C" {
+    pub fn cow_create(sz: usize) -> *mut RawHandle;
+    pub fn cow_free(cow: *mut RawHandle);
+    pub fn cow_clone(cow: *const RawHandle) -> *mut RawHandle;
+
+    pub fn cow_is_fake(cow: *const RawHandle) -> i32;
+    pub fn cow_size(cow: *const RawHandle) -> usize;
+
+    pub fn cow_err() -> i32;
+    pub fn cow_err_msg(kind: i32) -> *const *const u8;
+}
+
+#[inline(always)] pub unsafe fn cow_area_mut(cow: *mut RawHandle) -> *mut c_void
+{
+    *cow
+}
+#[inline(always)] pub unsafe fn cow_area(cow: *const RawHandle) -> *const c_void
+{
+    (*cow) as *const _
+}
diff --git a/cowslice/src/lib.rs b/cowslice/src/lib.rs
new file mode 100644
index 0000000..2945950
--- /dev/null
+++ b/cowslice/src/lib.rs
@@ -0,0 +1,25 @@
+
+#![allow(dead_code)]
+
+mod ffi;
+
+#[cfg(test)]
+mod tests {
+    #[test]
+    fn it_works() {
+        assert_eq!(2 + 2, 4);
+    }
+    #[test]
+    fn link_works() {
+	
+	unsafe {
+	    let raw_h = super::ffi::cow_create(100);
+	    assert_ne!(raw_h as usize, 0);
+	    println!("Raw handle pointer is {:p}", raw_h);
+	    super::ffi::cow_free(raw_h);
+	}
+	unsafe {
+	    assert_eq!(super::ffi::cow_err(), 1, "There was an error in `cow_free`");
+	}
+    }
+}