Allow querying the scripts of nodes in Godot (#99)

This allows you to get access to the underlying values stored in the
scripts, which likely contain a lot of important information for the
auto splitter.

.github/workflows/build.yml

@@ -10,36 +10,21 @@ on:
 
 jobs:
   build:
-    runs-on: ${{ matrix.os }}
+    runs-on: ubuntu-latest
     strategy:
       fail-fast: false
       matrix:
-        label:
-          - WebAssembly Unknown
-          - WebAssembly WASI
-
-        include:
-          - label: WebAssembly Unknown
-            target: wasm32-unknown-unknown
-            os: ubuntu-latest
-            install_target: true
-          - label: WebAssembly WASI
-            target: wasm32-wasi
-            os: ubuntu-latest
-            install_target: true
-
+        target: [wasm32-unknown-unknown, wasm32-wasip1]
+        toolchain: [stable, nightly]
     steps:
       - name: Checkout Commit
         uses: actions/checkout@v4
 
       - name: Install Rust
         uses: hecrj/setup-rust-action@v2
         with:
-          rust-version: ${{ matrix.toolchain || 'stable' }}
-
-      - name: Install Target
-        if: matrix.install_target != ''
-        run: rustup target add ${{ matrix.target }}
+          targets: ${{ matrix.target }}
+          rust-version: ${{ matrix.toolchain }}
 
       - name: Build (No Default Features)
         run: |
@@ -53,14 +38,19 @@ jobs:
         run: |
           cargo build --all-features --target ${{ matrix.target }}
 
-      - name: Test (Target, All Features)
-        run: |
-          cargo test --all-features
+  test:
+    name: Test (Host)
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout Commit
+        uses: actions/checkout@v4
 
-      # Test on the host to also run the doc tests
-      - name: Test (Host, All Features)
+      - name: Install Rust
+        uses: hecrj/setup-rust-action@v2
+
+      - name: Test (All Features)
         run: |
-          cargo test --target x86_64-unknown-linux-gnu --all-features
+          cargo test --all-features
 
   clippy:
     name: Check clippy lints

.github/workflows/docs.yml

@@ -37,10 +37,10 @@ jobs:
         with:
           components: rust-docs
           rust-version: nightly
-          targets: wasm32-wasi
+          targets: wasm32-wasip1
 
       - name: Build docs
-        run: RUSTDOCFLAGS="--cfg doc_cfg" cargo doc --all-features --target wasm32-wasi
+        run: RUSTDOCFLAGS="--cfg doc_cfg" cargo doc --all-features --target wasm32-wasip1
 
       - name: Setup Pages
         uses: actions/configure-pages@v3
@@ -61,12 +61,12 @@ jobs:
             --exclude=.github \
             .
         env:
-          INPUT_PATH: target/wasm32-wasi/doc
+          INPUT_PATH: target/wasm32-wasip1/doc
 
       - name: Upload artifact
         uses: actions/upload-pages-artifact@v1
         with:
-          path: target/wasm32-wasi/doc
+          path: target/wasm32-wasip1/doc
 
       - name: Deploy to GitHub Pages
         id: deployment

src/game_engine/godot/core/mod.rs

@@ -2,8 +2,10 @@ mod object;
 mod os;
 mod string;
 mod templates;
+mod variant;
 
 pub use object::*;
 pub use os::*;
 pub use string::*;
 pub use templates::*;
+pub use variant::*;

src/game_engine/godot/core/object/mod.rs

@@ -1,3 +1,7 @@
 mod object;
+mod script_instance;
+mod script_language;
 
 pub use object::*;
+pub use script_instance::*;
+pub use script_language::*;

src/game_engine/godot/core/object/object.rs

@@ -1,10 +1,62 @@
 //! <https://github.com/godotengine/godot/blob/07cf36d21c9056fb4055f020949fb90ebd795afb/core/object/object.h>
 
 use crate::{
-    game_engine::godot::{Ptr, VTable},
+    game_engine::godot::{Ptr, VTable, VariantType},
     Error, Process,
 };
 
+use super::ScriptInstance;
+
+#[allow(unused)]
+mod offsets {
+    // *const VTable
+    pub const VTABLE_PTR: u64 = 0x0;
+    // *const ObjectGDExtension
+    pub const EXTENSION: u64 = 0x8;
+    // GDExtensionClassInstancePtr
+    pub const EXTENSION_INSTANCE: u64 = 0x10;
+    // HashMap<StringName, SignalData>
+    pub const SIGNAL_MAP: u64 = 0x18;
+    // List<Connection>
+    pub const CONNECTIONS: u64 = 0x48;
+    // bool
+    pub const BLOCK_SIGNALS: u64 = 0x50;
+    // i32
+    pub const PREDELETE_OK: u64 = 0x54;
+    // ObjectID
+    pub const INSTANCE_ID: u64 = 0x58;
+    // bool
+    pub const CAN_TRANSLATE: u64 = 0x60;
+    // bool
+    pub const EMITTING: u64 = 0x61;
+    // *const ScriptInstance
+    pub const SCRIPT_INSTANCE: u64 = 0x68;
+    // Variant
+    pub const SCRIPT: u64 = 0x70;
+    // HashMap<StringName, Variant>
+    pub const METADATA: u64 = 0x88;
+    // HashMap<StringName, Variant*>
+    pub const METADATA_PROPERTIES: u64 = 0xb8;
+    // *const StringName
+    pub const CLASS_NAME_PTR: u64 = 0xe8;
+}
+
+/// Information about a property of a script. This is not publicly exposed in
+/// Godot.
+///
+/// Check the [`Ptr<PropertyInfo>`] documentation to see all the methods you can
+/// call on it.
+#[derive(Debug, Copy, Clone)]
+#[repr(transparent)]
+pub struct PropertyInfo;
+
+impl Ptr<PropertyInfo> {
+    /// Returns the type of the property as a [`VariantType`].
+    pub fn get_variant_type(self, process: &Process) -> Result<VariantType, Error> {
+        self.read_at_byte_offset(0x0, process)
+    }
+}
+
 /// Base class for all other classes in the engine.
 ///
 /// [`Object`](https://docs.godotengine.org/en/4.2/classes/class_object.html)
@@ -18,6 +70,19 @@ pub struct Object;
 impl Ptr<Object> {
     /// Returns a pointer to the object's virtual method table.
     pub fn get_vtable(self, process: &Process) -> Result<Ptr<VTable>, Error> {
-        process.read(self.addr())
+        self.read_at_byte_offset(offsets::VTABLE_PTR, process)
+    }
+
+    /// Returns the object's Script instance, or [`None`] if no script is
+    /// attached.
+    ///
+    /// [`Object.get_script`](https://docs.godotengine.org/en/4.2/classes/class_object.html#class-object-method-get-script)
+    pub fn get_script_instance(
+        self,
+        process: &Process,
+    ) -> Result<Option<Ptr<ScriptInstance>>, Error> {
+        let ptr: Ptr<ScriptInstance> =
+            self.read_at_byte_offset(offsets::SCRIPT_INSTANCE, process)?;
+        Ok(if ptr.is_null() { None } else { Some(ptr) })
     }
 }

src/game_engine/godot/core/object/script_instance.rs

@@ -0,0 +1,12 @@
+//! <https://github.com/godotengine/godot/blob/07cf36d21c9056fb4055f020949fb90ebd795afb/core/object/script_instance.h>
+
+/// An instance of a [`Script`](super::Script).
+///
+/// You need to cast this to a
+/// [`GDScriptInstance`](crate::game_engine::godot::GDScriptInstance) or
+/// [`CSharpScriptInstance`](crate::game_engine::godot::CSharpScriptInstance) to
+/// do anything meaningful with it. Make sure to verify the script language
+/// before casting.
+#[derive(Debug, Copy, Clone)]
+#[repr(transparent)]
+pub struct ScriptInstance;

src/game_engine/godot/core/object/script_language.rs

@@ -0,0 +1,12 @@
+//! <https://github.com/godotengine/godot/blob/07cf36d21c9056fb4055f020949fb90ebd795afb/core/object/script_language.h>
+
+/// A class stored as a resource.
+///
+/// [`Script`](https://docs.godotengine.org/en/4.2/classes/class_script.html)
+///
+/// You need to cast this to a [`GDScript`](crate::game_engine::godot::GDScript)
+/// or [`CSharpScript`](crate::game_engine::godot::CSharpScript) to do anything
+/// meaningful with it. Make sure to verify the script language before casting.
+#[derive(Debug, Copy, Clone)]
+#[repr(transparent)]
+pub struct Script;

src/game_engine/godot/core/string/string_name.rs

@@ -6,29 +6,82 @@ use arrayvec::ArrayVec;
 use bytemuck::{Pod, Zeroable};
 
 use crate::{
-    game_engine::godot::{KnownSize, Ptr},
+    game_engine::godot::{Hash, Ptr, SizeInTargetProcess},
     Address64, Error, Process,
 };
 
 use super::String;
 
+#[allow(unused)]
+mod offsets {
+    pub mod data {
+        use super::super::{SizeInTargetProcess, String};
+
+        pub const REFCOUNT: u64 = 0x00;
+        pub const STATIC_COUNT: u64 = 0x04;
+        pub const CNAME: u64 = 0x08;
+        pub const NAME: u64 = 0x10;
+        pub const IDX: u64 = NAME + String::<0>::SIZE;
+        pub const HASH: u64 = IDX + 0x4;
+    }
+}
+
 /// A built-in type for unique strings.
 ///
 /// [`StringName`](https://docs.godotengine.org/en/4.2/classes/class_stringname.html)
 #[derive(Debug, Copy, Clone, Pod, Zeroable)]
 #[repr(transparent)]
-pub struct StringName(Ptr<StringNameData>);
+pub struct StringName {
+    data: Ptr<Data>,
+}
+
+impl<const N: usize> Hash<[u8; N]> for StringName {
+    fn hash_of_lookup_key(lookup_key: &[u8; N]) -> u32 {
+        // String::hash
+        let mut hashv: u32 = 5381;
+
+        for c in lossy_chars(lookup_key) {
+            hashv = hashv.wrapping_mul(33).wrapping_add(c as u32);
+        }
+
+        hashv
+    }
+
+    fn eq(&self, lookup_key: &[u8; N], process: &Process) -> bool {
+        let Ok(name) = self.read::<N>(process) else {
+            return false;
+        };
+        name.chars().eq(lossy_chars(lookup_key))
+    }
+}
 
-impl KnownSize for StringName {}
+fn lossy_chars(lookup_key: &[u8]) -> impl Iterator<Item = char> + '_ {
+    lookup_key.utf8_chunks().flat_map(|chunk| {
+        chunk.valid().chars().chain(if chunk.invalid().is_empty() {
+            None
+        } else {
+            Some(char::REPLACEMENT_CHARACTER)
+        })
+    })
+}
+
+impl SizeInTargetProcess for StringName {
+    const SIZE: u64 = 0x8;
+}
 
 #[derive(Debug, Copy, Clone, Pod, Zeroable)]
 #[repr(transparent)]
-struct StringNameData(Address64);
+struct Data(Address64);
 
 impl StringName {
     /// Reads the string from the target process.
     pub fn read<const N: usize>(self, process: &Process) -> Result<String<N>, Error> {
-        let cow_data: Address64 = self.0.read_at_offset(0x10, process)?;
+        // FIXME: This skips cname entirely atm.
+
+        // FIXME: Use CowData
+        let cow_data: Address64 = self
+            .data
+            .read_at_byte_offset(offsets::data::NAME, process)?;
 
         // Only on 4.2 or before.
         let len = process

src/game_engine/godot/core/string/ustring.rs

@@ -2,12 +2,18 @@
 
 use arrayvec::{ArrayString, ArrayVec};
 
+use crate::game_engine::godot::SizeInTargetProcess;
+
 /// A built-in type for strings.
 ///
 /// [`String`](https://docs.godotengine.org/en/4.2/classes/class_string.html)
 #[derive(Clone)]
 pub struct String<const N: usize>(pub(super) ArrayVec<u32, N>);
 
+impl<const N: usize> SizeInTargetProcess for String<N> {
+    const SIZE: u64 = 0x8;
+}
+
 impl<const N: usize> String<N> {
     /// Returns an iterator over the characters in this string.
     pub fn chars(&self) -> impl Iterator<Item = char> + '_ {

src/game_engine/godot/core/templates/cowdata.rs

@@ -0,0 +1,30 @@
+//! <https://github.com/godotengine/godot/blob/07cf36d21c9056fb4055f020949fb90ebd795afb/core/templates/cowdata.h>
+
+use bytemuck::{Pod, Zeroable};
+
+use crate::game_engine::godot::Ptr;
+
+/// A copy-on-write data type. This is not publicly exposed in Godot.
+#[repr(transparent)]
+pub struct CowData<T>(Ptr<T>);
+
+impl<T> Copy for CowData<T> {}
+
+impl<T> Clone for CowData<T> {
+    fn clone(&self) -> Self {
+        *self
+    }
+}
+
+// SAFETY: The type is transparent over a `Ptr`, which is `Pod`.
+unsafe impl<T: 'static> Pod for CowData<T> {}
+
+// SAFETY: The type is transparent over a `Ptr`, which is `Zeroable`.
+unsafe impl<T> Zeroable for CowData<T> {}
+
+impl<T> CowData<T> {
+    /// Returns the pointer to the underlying data.
+    pub fn ptr(self) -> Ptr<T> {
+        self.0
+    }
+}