add Rust example

flake.lock

@@ -1,18 +1,17 @@
 {
   "nodes": {
-    "borsh": {
-      "flake": false,
+    "crane": {
       "locked": {
-        "lastModified": 1716294836,
-        "narHash": "sha256-dEv3m7U7buQr9kX68U+r5Ro4KRXesGsSpqBs2CLddaY=",
-        "owner": "khazaddum",
-        "repo": "borsh",
-        "rev": "b8e5cfd6ed875707fa82698d5c356ac062203e71",
+        "lastModified": 1744386647,
+        "narHash": "sha256-DXwQEJllxpYeVOiSlBhQuGjfvkoGHTtILLYO2FvcyzQ=",
+        "owner": "ipetkov",
+        "repo": "crane",
+        "rev": "d02c1cdd7ec539699aa44e6ff912e15535969803",
         "type": "github"
       },
       "original": {
-        "owner": "khazaddum",
-        "repo": "borsh",
+        "owner": "ipetkov",
+        "repo": "crane",
         "type": "github"
       }
     },
@@ -82,10 +81,31 @@
     },
     "root": {
       "inputs": {
-        "borsh": "borsh",
+        "crane": "crane",
         "flake-parts": "flake-parts",
         "haskell-flake": "haskell-flake",
-        "nixpkgs": "nixpkgs"
+        "nixpkgs": "nixpkgs",
+        "rust-overlay": "rust-overlay"
+      }
+    },
+    "rust-overlay": {
+      "inputs": {
+        "nixpkgs": [
+          "nixpkgs"
+        ]
+      },
+      "locked": {
+        "lastModified": 1744803954,
+        "narHash": "sha256-f+gE6JtLhPzyDWOCEHbN/S30GEGHMtXEt41+Va7wzEU=",
+        "owner": "oxalica",
+        "repo": "rust-overlay",
+        "rev": "c564fb830c7d5b3e4fde5ea829a62f0e41e43a20",
+        "type": "github"
+      },
+      "original": {
+        "owner": "oxalica",
+        "repo": "rust-overlay",
+        "type": "github"
       }
     }
   },

flake.nix

@@ -4,10 +4,11 @@
     nixpkgs.url = "github:nixos/nixpkgs/nixpkgs-unstable";
     flake-parts.url = "github:hercules-ci/flake-parts";
     haskell-flake.url = "github:srid/haskell-flake";
-    borsh = {
-      url = "github:khazaddum/borsh";
-      flake = false;
+    rust-overlay = {
+      url = "github:oxalica/rust-overlay";
+      inputs.nixpkgs.follows = "nixpkgs";
     };
+    crane.url = "github:ipetkov/crane";
   };
   outputs = inputs @ {
     self,
@@ -27,7 +28,42 @@
         system,
         ...
       }: let
+        craneLib = (inputs.crane.mkLib pkgs).overrideToolchain (p: p.rust-bin.selectLatestNightlyWith (toolchain: toolchain.default));
+        rustbits = pkgs: let
+          cargoCbuild = {
+            cargoArtifacts,
+            cargoAwesomeExtraArgs ? "", # Arguments that are generally useful default
+            cargoExtraArgs ? "", # Other cargo-general flags (e.g. for features or targets)
+          } @ origArgs: let
+            # Clean the original arguments for good hygiene (i.e. so the flags specific
+            # to this helper don't pollute the environment variables of the derivation)
+            args = builtins.removeAttrs origArgs [
+              "cargoAwesomeExtraArgs"
+              "cargoExtraArgs"
+            ];
+          in
+            craneLib.mkCargoDerivation (args
+              // {
+                inherit cargoArtifacts;
+
+                src = cargoArtifacts;
+                pname = "rustbits";
+                version = "0.1.0";
+                pnameSuffix = "-cbuild";
+
+                buildPhaseCargoCommand = "cargo cinstall --prefix=$out --libdir=$out/lib --includedir=$out/include --pkgconfigdir=$out/lib/pkgconfig ${cargoAwesomeExtraArgs}";
+
+                nativeBuildInputs = (args.nativeBuildInputs or []) ++ [pkgs.cargo-c];
+              });
+        in
+          cargoCbuild {
+            cargoArtifacts = craneLib.cleanCargoSource ./rustbits/.;
+          };
       in {
+        _module.args.pkgs = import inputs.nixpkgs {
+          inherit system;
+          overlays = [(import inputs.rust-overlay)];
+        };
         haskellProjects.default = {
           # The base package set representing a specific GHC version.
           # By default, this is pkgs.haskellPackages.
@@ -44,15 +80,17 @@
           #   shower.source = inputs.shower;
           # };
           packages = {
-            borsh.source = inputs.borsh;
           };
 
           settings = {
+            rustbits.custom = _: rustbits pkgs;
             foreign-rust = {
-              check = false;
+              #check = false;
+            };
+            borsh = {
+              broken = false;
             };
           
-          autoWire = ["packages" "devShells"];
           };
 
            devShell = {

foreign-rust.cabal

@@ -121,6 +121,8 @@ test-suite test-foreign-rust
     , tasty
     , tasty-hunit
     , template-haskell
+  pkgconfig-depends:
+    rustbits
 
 --test-suite demo-annotated
   --import:

rustbits/Cargo.toml

@@ -0,0 +1,13 @@
+[package]
+name = "rustbits"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+haskell-ffi = { git = "https://code.vergara.tech/Vergara_Tech/haskell-rust-ffi.git", rev = "2bf292e2e56eac8e9fb0fb2e1450cf4a4bd01274" }
+
+[features]
+capi = []
+
+[package.metadata.capi.library]
+versioning = false

rustbits/cbindgen.toml

@@ -0,0 +1,4 @@
+include_guard = "RUST_WRAPPER_H"
+include_version = false
+language = "C"
+

rustbits/src/lib.rs

@@ -0,0 +1,39 @@
+use haskell_ffi::{
+    error::Result,
+    from_haskell::marshall_from_haskell_var,
+    to_haskell::marshall_to_haskell_var,
+    FromHaskell, ToHaskell
+};
+
+pub enum RW {}
+pub const RW: PhantomData<RW> = PhantomData;
+
+#[derive(Debug, BorshSerialize, BorshDeserialize)]
+pub struct Hhex {
+    bytes: Vec<u8>
+}
+
+impl<RW> ToHaskell<RW> for Hhex {
+    fn to_haskell<W: Write>(&self, writer: &mut W, _tag: PhantomData<RW>) -> Result<()> {
+        self.serialize(writer)?;
+        Ok(())
+    }
+}
+
+impl<RW> FromHaskell<RW> for Hhex {
+    fn from_haskell(buf: &mut &[u8], _tag: PhantomData<RW>) -> Result<Self> {
+        let x = Hhex::deserialize(buf)?;
+        Ok(x)
+    }
+}
+
+#[no_mangle]
+pub extern "C" fn marshalling_test (
+    input: *const u8,
+    input_len: usize,
+    out: *mut u8,
+    out_len: &mut usize
+){
+    let x: Vec<u8> = marshall_from_haskell_var(input, input_len, RW);
+    marshall_to_haskell_var(&x, out, out_len, RW);
+}