Update readRef method to allow reuse RefData (#243)

crates/lune-std-ffi/src/c/arr_info.rs

@@ -6,7 +6,7 @@ use mlua::prelude::*;
 use super::{association_names::CARR_INNER, helper, method_provider};
 use crate::ffi::{association, libffi_helper::get_ensured_size, FfiConvert, FfiData, FfiSize};
 
-// This is a series of some type.
+// Series of some type.
 // It provides the final size and the offset of the index,
 // but does not allow multidimensional arrays because of API complexity.
 // Multidimensional arrays can be implemented

crates/lune-std-ffi/src/c/fn_info.rs

@@ -16,22 +16,7 @@ use crate::{
     },
 };
 
-// cfn is a type declaration for a function.
+// Function pointer type
-// Basically, when calling an external function, this type declaration
-// is referred to and type conversion is automatically assisted.
-
-// However, in order to save on type conversion costs,
-// users keep values ​​they will use continuously in a box and use them multiple times.
-// Alternatively, if the types are the same,you can save the cost of creating
-// a new space by directly passing FfiRaw,
-// the result value of another function or the argument value of the callback.
-
-// Defining cfn simply lists the function's actual argument positions and conversions.
-// You must decide how to process the data in Lua.
-
-// The name cfn is intentional. This is because any *c_void is
-// moved to a Lua function or vice versa.
-
 pub struct CFnInfo {
     cif: Cif,
     arg_info_list: Vec<FfiArg>,
@@ -147,6 +132,7 @@ impl CFnInfo {
         }
     }
 
+    // Create ClosureData with lua function
     pub fn create_closure<'lua>(
         &self,
         lua: &'lua Lua,
@@ -167,6 +153,7 @@ impl CFnInfo {
         Ok(closure_data)
     }
 
+    // Create CallableData from RefData
     pub fn create_callable<'lua>(
         &self,
         lua: &'lua Lua,
@@ -209,10 +196,6 @@ impl LuaUserData for CFnInfo {
         fields.add_field_method_get("size", |_lua, _this| Ok(SIZE_OF_POINTER));
     }
     fn add_methods<'lua, M: LuaUserDataMethods<'lua, Self>>(methods: &mut M) {
-        // Subtype
-        method_provider::provide_ptr(methods);
-        method_provider::provide_arr(methods);
-
         // ToString
         method_provider::provide_to_string(methods);
 

crates/lune-std-ffi/src/c/ptr_info.rs

@@ -5,7 +5,7 @@ use mlua::prelude::*;
 
 use super::{association_names::CPTR_INNER, ctype_helper, helper, method_provider};
 use crate::{
-    data::{GetFfiData, RefBounds, RefData, RefFlag},
+    data::{GetFfiData, RefData, RefFlag, UNSIZED_BOUNDS},
     ffi::{
         association, libffi_helper::SIZE_OF_POINTER, FfiConvert, FfiData, FfiSignedness, FfiSize,
     },
@@ -16,7 +16,6 @@ const READ_REF_FLAGS: u8 =
     RefFlag::Offsetable.value() | RefFlag::Readable.value() | RefFlag::Writable.value();
 
 pub struct CPtrInfo {
-    inner_size: usize,
     inner_is_cptr: bool,
 }
 
@@ -33,7 +32,7 @@ impl FfiSize for CPtrInfo {
 }
 
 impl FfiConvert for CPtrInfo {
-    // Convert luavalue into data, then write into ptr
+    // Write address of RefData
     unsafe fn value_into_data<'lua>(
         &self,
         _lua: &'lua Lua,
@@ -41,12 +40,12 @@ impl FfiConvert for CPtrInfo {
         data_handle: &Ref<dyn FfiData>,
         value: LuaValue<'lua>,
     ) -> LuaResult<()> {
-        let value_userdata = value.as_userdata().ok_or_else(|| {
+        let LuaValue::UserData(value_userdata) = value else {
-            LuaError::external(format!(
+            return Err(LuaError::external(format!(
                 "Value must be a RefData, BoxData or ClosureData, got {}",
                 value.type_name()
-            ))
+            )));
-        })?;
+        };
         *data_handle
             .get_inner_pointer()
             .byte_offset(offset)
@@ -54,24 +53,30 @@ impl FfiConvert for CPtrInfo {
         Ok(())
     }
 
-    // Read data from ptr, then convert into luavalue
+    // Read address, create RefData
     unsafe fn value_from_data<'lua>(
         &self,
         lua: &'lua Lua,
         offset: isize,
         data_handle: &Ref<dyn FfiData>,
     ) -> LuaResult<LuaValue<'lua>> {
-        Ok(LuaValue::UserData(lua.create_userdata(RefData::new(
+        Ok(LuaValue::UserData(
-            unsafe { data_handle.get_inner_pointer().byte_offset(offset) },
+            lua.create_userdata(RefData::new(
-            if self.inner_is_cptr {
+                *data_handle
-                READ_CPTR_REF_FLAGS
+                    .get_inner_pointer()
-            } else {
+                    .byte_offset(offset)
-                READ_REF_FLAGS
+                    .cast::<*mut ()>(),
-            },
+                if self.inner_is_cptr {
-            RefBounds::new(0, self.inner_size),
+                    READ_CPTR_REF_FLAGS
-        ))?))
+                } else {
+                    READ_REF_FLAGS
+                },
+                UNSIZED_BOUNDS,
+            ))?,
+        ))
     }
 
+    // Copy Address
     unsafe fn copy_data(
         &self,
         _lua: &Lua,
@@ -82,7 +87,10 @@ impl FfiConvert for CPtrInfo {
     ) -> LuaResult<()> {
         *dst.get_inner_pointer()
             .byte_offset(dst_offset)
-            .cast::<*mut ()>() = src.get_inner_pointer().byte_offset(src_offset);
+            .cast::<*mut ()>() = *src
+            .get_inner_pointer()
+            .byte_offset(src_offset)
+            .cast::<*mut ()>();
         Ok(())
     }
 }
@@ -95,7 +103,6 @@ impl CPtrInfo {
         inner: &LuaAnyUserData,
     ) -> LuaResult<LuaAnyUserData<'lua>> {
         let value = lua.create_userdata(Self {
-            inner_size: helper::get_size(inner)?,
             inner_is_cptr: inner.is::<CPtrInfo>(),
         })?;
 
@@ -143,8 +150,36 @@ impl LuaUserData for CPtrInfo {
 
         methods.add_method(
             "readRef",
-            |lua, this, (target, offset): (LuaAnyUserData, Option<isize>)| unsafe {
+            |lua,
-                this.value_from_data(lua, offset.unwrap_or(0), &target.get_ffi_data()?)
+             this,
+             (target, offset, ref_data): (
+                LuaAnyUserData,
+                Option<isize>,
+                Option<LuaAnyUserData>,
+            )| unsafe {
+                if let Some(ref_userdata) = ref_data {
+                    if !ref_userdata.is::<RefData>() {
+                        return Err(LuaError::external(""));
+                    }
+                    RefData::update(
+                        lua,
+                        ref_userdata.clone(),
+                        *target
+                            .get_ffi_data()?
+                            .get_inner_pointer()
+                            .byte_offset(offset.unwrap_or(0))
+                            .cast::<*mut ()>(),
+                        if this.inner_is_cptr {
+                            READ_CPTR_REF_FLAGS
+                        } else {
+                            READ_REF_FLAGS
+                        },
+                        UNSIZED_BOUNDS,
+                    )?;
+                    Ok(LuaValue::UserData(ref_userdata))
+                } else {
+                    this.value_from_data(lua, offset.unwrap_or(0), &target.get_ffi_data()?)
+                }
             },
         );
         methods.add_method(

crates/lune-std-ffi/src/data/mod.rs

@@ -15,7 +15,7 @@ pub use self::{
     callable_data::CallableData,
     closure_data::ClosureData,
     lib_data::LibData,
-    ref_data::{create_nullref, RefBounds, RefData, RefFlag},
+    ref_data::{create_nullref, RefBounds, RefData, RefFlag, UNSIZED_BOUNDS},
 };
 use crate::ffi::FfiData;
 

crates/lune-std-ffi/src/data/ref_data/mod.rs

@@ -41,6 +41,23 @@ impl RefData {
         }
     }
 
+    pub fn update<'lua>(
+        lua: &'lua Lua,
+        this: LuaAnyUserData<'lua>,
+        ptr: *mut (),
+        flags: u8,
+        boundary: RefBounds,
+    ) -> LuaResult<()> {
+        let mut target = this.borrow_mut::<RefData>()?;
+        association::set(lua, REF_INNER, &this, LuaNil)?;
+
+        **target.ptr = ptr;
+        target.flags = flags;
+        target.boundary = boundary;
+
+        Ok(())
+    }
+
     // Create reference of this reference
     pub fn luaref<'lua>(
         lua: &'lua Lua,

types/ffi.luau

@@ -1,6 +1,6 @@
 --[=[
 	@class FFI
-	
+
 	Built-in library for foreign function interface.
 
 	### Example usage
@@ -30,7 +30,7 @@
 	local result = ffi.box(ffi.c.int.size)
 	local a = ffi.c.int:box(1)
 	local b = ffi.c.int:box(2)
-	
+
 	-- Call external function
 	add(result, a:ref(), b:ref())
 
@@ -51,8 +51,8 @@ ffi.c = c
 --#region Data
 --[=[
 	@class RefData
-	
+
-	A user manageable memory reference box.
+	A user manageable memory reference.
 
 	It can be GCed, But it doesn't free the referenced memory.
 ]=]
@@ -140,7 +140,7 @@ export type RefData = {
 
 --[=[
 	@class BoxData
-	
+
 	A user manageable heap memory.
 ]=]
 export type BoxData = {
@@ -229,14 +229,12 @@ export type LibData = {
 	find: (self: LibData, sym: string) -> RefData,
 }
 
--- export type AppliedCallable = ()->()
-
 --[=[
 	@class CallableData
-	
+
 	A callable external function.
 
-	To call external function, you should provide memory for the return value and references for the arguments.
+	To call external function, provide memory for save the return value and references for the arguments.
 
 	If return type is `void`, pass `nil`.
 ]=]
@@ -246,13 +244,12 @@ export type CallableData = (
 ) -> () & {
 	-- apply: (self: Callable, args: Args)->AppliedCallable,
 }
+-- export type AppliedCallable = ()->()
 
 --[=[
 	@class ClosureData
-	
-	A lua function wrapper for the function pointer.
 
-	To return some data, write value into ret reference.
+	A reference that holds lua function.
 ]=]
 export type ClosureData = {
 	--[=[
@@ -290,7 +287,7 @@ export type CTypeInfo<T, R> = {
 	]=]
 	signedness: boolean,
 
-	-- subtype
+	-- Subtype
 	--[=[
 		@within CTypeInfo
 		@tag Method
@@ -301,7 +298,6 @@ export type CTypeInfo<T, R> = {
 		@return A pointer subtype
 	]=]
 	ptr: (self: CTypeInfo<T, R>) -> CPtrInfo<CTypeInfo<T, R>>,
-
 	--[=[
 		@within CTypeInfo
 		@tag Method
@@ -314,7 +310,7 @@ export type CTypeInfo<T, R> = {
 	]=]
 	arr: (self: CTypeInfo<T, R>, len: number) -> CArrInfo<CTypeInfo<T, R>, R>,
 
-	-- realize
+	-- Create/Read/Write/Copy
 	--[=[
 		@within CTypeInfo
 		@tag Method
@@ -326,33 +322,30 @@ export type CTypeInfo<T, R> = {
 		@return A box
 	]=]
 	box: (self: CTypeInfo<T, R>, val: R) -> BoxData,
-
 	--[=[
 		@within CTypeInfo
 		@tag Method
 		@method readData
 
-		Read a lua table from reference or box.
+		Read a lua value from reference or box.
 
 		@param target Target to read data from
 		@param offset Offset to read data from
-		@return A table
+		@return A lua value
 	]=]
 	readData: (self: CTypeInfo<T, R>, target: RefData | BoxData, offset: number?) -> R,
-
 	--[=[
 		@within CTypeInfo
 		@tag Method
 		@method writeData
 
-		Write a lua table into reference or box.
+		Write a lua value into reference or box.
 
 		@param target Target to write data into
-		@param table Lua data to write
+		@param value Lua data to write
 		@param offset Offset to write data into
 	]=]
 	writeData: (self: CTypeInfo<T, R>, target: RefData | BoxData, value: R, offset: number?) -> (),
-
 	--[=[
 		@within CTypeInfo
 		@tag Method
@@ -372,7 +365,6 @@ export type CTypeInfo<T, R> = {
 		dstOffset: number?,
 		srcOffset: number?
 	) -> (),
-
 	--[=[
 		@within CTypeInfo
 		@tag Method
@@ -385,6 +377,7 @@ export type CTypeInfo<T, R> = {
 	]=]
 	stringifyData: (self: CTypeInfo<T, R>, target: RefData | BoxData, offset: number?) -> string,
 
+	-- ETC
 	-- FIXME: recursive types; 'intoType' should be CTypes
 	--[=[
 		@within CTypeInfo
@@ -432,7 +425,7 @@ export type CPtrInfo<T> = {
 	]=]
 	inner: T,
 
-	-- subtype
+	-- Subtype
 	-- FIXME: recursive types; result 'any' should be CArrInfo<CPtrInfo<T>>
 	--[=[
 		@within CPtrInfo
@@ -457,34 +450,46 @@ export type CPtrInfo<T> = {
 	]=]
 	ptr: (self: CPtrInfo<T>) -> any,
 
+	-- Address
 	--[=[
 		@within CPtrInfo
 		@tag Method
 		@Method readRef
-	
+
-		Similar to readData, read a lua value from reference.
+		Read address from data, then return RefData.
-	
+
-		@param target Target reference to read data from
+		Useful when reading pointer fields of structures.
-		@param offset Offset to read data from
+
+		If the `ref` argument is given, rather than create new RefData, update it.
+
+		@param target Target data to read address from
+		@param offset Offset to read address from
+		@param ref RefData to update
 		@return A lua value
 	]=]
-	readRef: (self: CPtrInfo<T>, target: RefData | BoxData, offset: number?) -> any,
+	readRef: (
-
+		self: CPtrInfo<T>,
+		target: RefData | BoxData,
+		offset: number?,
+		ref: RefData?
+	) -> RefData,
 	--[=[
 		@within CPtrInfo
 		@tag Method
 		@Method writeRef
 
-	 	Similar to writeData, write a lua value into reference.
+		Write address to data.
 	
-		@param target Target reference to write data into
+		Useful when writing pointer fields of structures.
-		@param value Lua data to write
+
-		@param offset Offset to write data into
+		@param target Target data to write address into
+		@param ref Memory address to write
+		@param offset Offset to write address into
 	]=]
 	writeRef: (
 		self: CPtrInfo<T>,
 		target: RefData | BoxData,
-		value: RefData | BoxData,
+		ref: RefData | BoxData | ClosureData,
 		offset: number?
 	) -> (),
 }
@@ -520,7 +525,7 @@ export type CArrInfo<T, R> = {
 	]=]
 	inner: T,
 
-	-- subtype
+	-- Subtype
 	--[=[
 		@within CArrInfo
 		@tag Method
@@ -532,7 +537,7 @@ export type CArrInfo<T, R> = {
 	]=]
 	ptr: (self: CArrInfo<T, R>) -> CPtrInfo<CArrInfo<T, R>>,
 
-	-- realize
+	-- Create/Read/Write/Copy
 	--[=[
 		@within CArrInfo
 		@tag Method
@@ -544,7 +549,6 @@ export type CArrInfo<T, R> = {
 		@return A box
 	]=]
 	box: (self: CArrInfo<T, R>, table: { T }) -> BoxData,
-
 	--[=[
 		@within CArrInfo
 		@tag Method
@@ -557,7 +561,6 @@ export type CArrInfo<T, R> = {
 		@return A table
 	]=]
 	readData: (self: CArrInfo<T, R>, target: RefData | BoxData, offset: number?) -> { T },
-
 	--[=[
 		@within CArrInfo
 		@tag Method
@@ -575,7 +578,6 @@ export type CArrInfo<T, R> = {
 		value: { R },
 		target_offset: number?
 	) -> (),
-
 	--[=[
 		@within CArrInfo
 		@tag Method
@@ -596,6 +598,7 @@ export type CArrInfo<T, R> = {
 		srcOffset: number?
 	) -> (),
 
+	-- ETC
 	--[=[
 		@within CArrInfo
 		@tag Method
@@ -612,7 +615,7 @@ export type CArrInfo<T, R> = {
 --[=[
 	@class CFnInfo
 
-	A c function signature type information.
+	A C function pointer type information, with function signature.
 ]=]
 export type CFnInfo = {
 	--[=[
@@ -625,6 +628,8 @@ export type CFnInfo = {
 		Equivalent to `ffi.c.usize.size`.
 	]=]
 	size: number,
+
+	-- Function
 	--[=[
 		@within CFnInfo
 		@tag Method
@@ -642,6 +647,8 @@ export type CFnInfo = {
 
 		Create a closure from lua function.
 
+		To return some data, lua function should write value into ret reference.
+
 		@return A closure
 	]=]
 	closure: (self: CFnInfo, (ret: RefData, ...RefData) -> ()) -> ClosureData,
@@ -662,6 +669,7 @@ export type CStructInfo = {
 	]=]
 	size: number,
 
+	-- Subtype
 	--[=[
 		@within CSturctInfo
 		@tag Method
@@ -684,6 +692,7 @@ export type CStructInfo = {
 	]=]
 	ptr: (self: CStructInfo) -> CPtrInfo<CStructInfo>,
 
+	-- Create/Read/Write/Copy
 	--[=[
 		@within CSturctInfo
 		@tag Method
@@ -744,6 +753,7 @@ export type CStructInfo = {
 		srcOffset: number?
 	) -> (),
 
+	-- ETC
 	--[=[
 		@within CSturctInfo
 		@tag Method
@@ -755,7 +765,6 @@ export type CStructInfo = {
 		@return The byte offset
 	]=]
 	offset: (self: CStructInfo, index: number) -> number,
-
 	--[=[
 		@within CSturctInfo
 		@tag Method
@@ -783,6 +792,8 @@ export type CVoidInfo = {
 		The size of the void type. It is always 0.
 	]=]
 	size: number,
+
+	-- Subtype
 	--[=[
 		@within CVoidInfo
 		@tag Method