Refactor Generated Code

data/function.h

@@ -0,0 +1,116 @@
+#include <functional>
+#include <utility>
+
+// Information Interface
+template <typename Ret, typename... Args>
+class __FunctionInfo {
+    typedef Ret (*type)(Args...);
+public:
+    [[nodiscard]] virtual bool can_overwrite() const = 0;
+    [[nodiscard]] virtual type get() const = 0;
+    [[nodiscard]] virtual type *get_addr() const = 0;
+    virtual void update(type new_func) = 0;
+};
+
+// Thunks
+typedef void *(*thunk_enabler_t)(void *target, void *thunk);
+extern thunk_enabler_t thunk_enabler;
+
+// Function
+template <unsigned int, typename T>
+class __Function;
+template <unsigned int discriminator, typename Ret, typename... Args>
+class __Function<discriminator, Ret(Args...)> final {
+    // Prevent Copying
+    __PREVENT_COPY(__Function);
+    __PREVENT_DESTRUCTION(__Function);
+
+    // Instance
+    static __Function<discriminator, Ret(Args...)> *instance;
+
+    // Current Function
+    typedef __FunctionInfo<Ret, Args...> *func_t;
+    const func_t func;
+
+public:
+    // Types
+    typedef Ret (*ptr_type)(Args...);
+    typedef std::function<Ret(Args...)> type;
+    typedef std::function<Ret(const type &, Args...)> overwrite_type;
+
+    // State
+    const bool enabled;
+    const char *const name;
+
+    // Backup Of Original Function Pointer
+    const ptr_type backup;
+
+#ifdef {{ BUILDING_SYMBOLS_GUARD }}
+    // Constructor
+    __Function(const char *const name_, const func_t func_):
+        func(func_),
+        enabled(func->can_overwrite()),
+        name(name_),
+        backup(func->get())
+    {
+        instance = this;
+    }
+#else
+    // Prevent Construction
+    __PREVENT_JUST_CONSTRUCTION(__Function);
+#endif
+
+    // Overwrite Function
+    [[nodiscard]] bool overwrite(const overwrite_type &target) {
+        // Check If Enabled
+        if (!enabled) {
+            return false;
+        }
+        // Enable Thunk
+        enable_thunk();
+        // Overwrite
+        type original = get_thunk_target();
+        thunk_target = [original, target](Args... args) {
+            return target(original, std::forward<Args>(args)...);
+        };
+        return true;
+    }
+
+    // Getters
+    [[nodiscard]] ptr_type get(const bool result_will_be_stored) {
+        if (!enabled) {
+            return nullptr;
+        } else {
+            if (result_will_be_stored) {
+                enable_thunk();
+            }
+            return func->get();
+        }
+    }
+    [[nodiscard]] ptr_type *get_vtable_addr() const {
+        return func->get_addr();
+    }
+
+private:
+    // Thunk
+    [[nodiscard]] type get_thunk_target() const {
+        if (thunk_target) {
+            return thunk_target;
+        } else {
+            return backup;
+        }
+    }
+    static Ret thunk(Args... args) {
+        return instance->get_thunk_target()(std::forward<Args>(args)...);
+    }
+    // Enable Thunk
+    type thunk_target;
+    bool thunk_enabled = false;
+    void enable_thunk() {
+        if (!thunk_enabled && enabled) {
+            ptr_type real_thunk = (ptr_type) thunk_enabler((void *) backup, (void *) thunk);
+            func->update(real_thunk);
+            thunk_enabled = true;
+        }
+    }
+};

data/internal.h

@@ -0,0 +1,10 @@
+#define __PREVENT_DESTRUCTION(self) \
+    ~self() = delete
+#define __PREVENT_JUST_CONSTRUCTION(self) \
+    self() = delete
+#define __PREVENT_CONSTRUCTION(self) \
+    __PREVENT_JUST_CONSTRUCTION(self); \
+    __PREVENT_DESTRUCTION(self)
+#define __PREVENT_COPY(self) \
+    self(const self &) = delete; \
+    self &operator=(const self &) = delete

data/out.cpp

@@ -1,10 +1,66 @@
-#define LEAN_SYMBOLS_HEADER
+#define {{ BUILDING_SYMBOLS_GUARD }}
 #include "{{ headerPath }}"
 
-// Thunk Template
+// Global Instance
-template <auto *const *func>
+template <unsigned int id, typename Ret, typename... Args>
-decltype(auto) __thunk(auto... args) {
+__Function<id, Ret(Args...)> *__Function<id, Ret(Args...)>::instance;
-    return (*func)->get_thunk_target()(std::forward<decltype(args)>(args)...);
+
-}
+// Normal Function Information
+template <typename Ret, typename... Args>
+class __NormalFunctionInfo final : public __FunctionInfo<Ret, Args...> {
+    typedef Ret (*type)(Args...);
+    type func;
+public:
+    // Constructor
+    explicit __NormalFunctionInfo(const type func_):
+        func(func_) {}
+    // Functions
+    [[nodiscard]] bool can_overwrite() const override {
+        return true;
+    }
+    [[nodiscard]] type get() const override {
+        return func;
+    }
+    [[nodiscard]] type *get_addr() const override {
+        return nullptr;
+    }
+    void update(const type new_func) override {
+        func = new_func;
+    }
+};
+
+// Virtual Function Information
+template <typename Ret, typename... Args>
+class __VirtualFunctionInfo final : public __FunctionInfo<Ret, Args...> {
+    typedef Ret (*type)(Args...);
+    type *const addr;
+    void *const parent;
+public:
+    // Constructor
+    __VirtualFunctionInfo(type *const addr_, void *const parent_):
+        addr(addr_),
+        parent(parent_) {}
+    // Functions
+    [[nodiscard]] bool can_overwrite() const override {
+        // If this function's address matches its parent's,
+        // then it was just inherited and does not actually exist.
+        // Overwriting this function would also overwrite its parent
+        // which would cause undesired behavior.
+        return get() != parent;
+    }
+    [[nodiscard]] type get() const override {
+        return *get_addr();
+    }
+    [[nodiscard]] type *get_addr() const override {
+        return addr;
+    }
+    void update(const type new_func) override {
+        // Address Should Have Already Been Updated
+        if (get() != new_func) {
+            __builtin_trap();
+        }
+    }
+};
+#undef super
 
 {{ main }}

data/out.h

@@ -5,153 +5,19 @@
 #error "Symbols Are ARM-Only"
 #endif
 
+// Internal Macros
+{{ include internal.h }}
+
+// Function Object
+{{ include function.h }}
+
 // Headers
-#include <variant>
-#include <functional>
 #include <cstddef>
 #include <string>
 #include <vector>
 #include <map>
-#include <type_traits>
 #include <cstring>
 
-// Internal Macros
-#define __PREVENT_DESTRUCTION(self) \
-    ~self() = delete
-#define __PREVENT_CONSTRUCTION(self) \
-    self() = delete; \
-    __PREVENT_DESTRUCTION(self)
-#define __PREVENT_COPY(self) \
-    self(const self &) = delete; \
-    self &operator=(const self &) = delete
-
-// Virtual Function Information
-struct __VirtualFunctionInfo {
-    // Constructors
-    template <typename Ret, typename Self, typename Super, typename... Args>
-    __VirtualFunctionInfo(Ret (**const addr_)(Self, Args...), Ret (*const parent_)(Super, Args...)):
-        addr((void **) addr_),
-        parent((void *) parent_) {}
-    template <typename T>
-    __VirtualFunctionInfo(T **const addr_, const std::nullptr_t parent_):
-        __VirtualFunctionInfo(addr_, (T *) parent_) {}
-    // Method
-    [[nodiscard]] bool can_overwrite() const {
-        return *addr != parent;
-    }
-    // Properties
-    void **const addr;
-    void *const parent;
-};
-
-// Thunks
-typedef void *(*thunk_enabler_t)(void *target, void *thunk);
-extern thunk_enabler_t thunk_enabler;
-
-// Function Information
-template <typename T>
-class __Function;
-template <typename Ret, typename... Args>
-class __Function<Ret(Args...)> {
-    // Prevent Copying
-    __PREVENT_COPY(__Function);
-    __PREVENT_DESTRUCTION(__Function);
-
-public:
-    // Types
-    typedef Ret (*ptr_type)(Args...);
-    typedef std::function<Ret(Args...)> type;
-    typedef std::function<Ret(const type &, Args...)> overwrite_type;
-
-    // Normal Function
-    __Function(const std::string name_, const ptr_type thunk_, const ptr_type func_):
-        func(func_),
-        enabled(true),
-        name(name_),
-        backup(func_),
-        thunk(thunk_) {}
-    // Virtual Function
-    template <typename Parent>
-    __Function(const std::string name_, const ptr_type thunk_, ptr_type *const func_, const Parent parent):
-        func(__VirtualFunctionInfo(func_, parent)),
-        enabled(std::get<__VirtualFunctionInfo>(func).can_overwrite()),
-        name(name_),
-        backup(*get_vtable_addr()),
-        thunk(thunk_) {}
-
-    // Overwrite Function
-    [[nodiscard]] bool overwrite(overwrite_type target) {
-        // Check If Enabled
-        if (!enabled) {
-            return false;
-        }
-        // Enable Thunk
-        enable_thunk();
-        // Overwrite
-        type original = get_thunk_target();
-        thunk_target = [original, target](Args... args) {
-            return target(original, std::forward<Args>(args)...);
-        };
-        return true;
-    }
-
-    // Getters
-    [[nodiscard]] ptr_type get(bool result_will_be_stored) {
-        if (!enabled) {
-            return nullptr;
-        } else {
-            if (result_will_be_stored) {
-                enable_thunk();
-            }
-            if (is_virtual()) {
-                return *get_vtable_addr();
-            } else {
-                return std::get<ptr_type>(func);
-            }
-        }
-    }
-    [[nodiscard]] ptr_type *get_vtable_addr() const {
-        return (ptr_type *) std::get<__VirtualFunctionInfo>(func).addr;
-    }
-    [[nodiscard]] type get_thunk_target() const {
-        if (thunk_target) {
-            return thunk_target;
-        } else {
-            return backup;
-        }
-    }
-
-private:
-    // Current Function
-    std::variant<ptr_type, __VirtualFunctionInfo> func;
-    [[nodiscard]] bool is_virtual() const {
-        return func.index() == 1;
-    }
-
-public:
-    // State
-    const bool enabled;
-    const std::string name;
-
-    // Backup Of Original Function Pointer
-    const ptr_type backup;
-
-private:
-    // Thunk
-    const ptr_type thunk;
-    type thunk_target;
-    bool thunk_enabled = false;
-    void enable_thunk() {
-        if (!thunk_enabled && enabled) {
-            ptr_type real_thunk = (ptr_type) thunk_enabler((void *) backup, (void *) thunk);
-            if (!is_virtual()) {
-                func = real_thunk;
-            }
-            thunk_enabled = true;
-        }
-    }
-};
-
 // Shortcuts
 typedef unsigned char uchar;
 typedef unsigned short ushort;

src/common.ts

@@ -9,7 +9,7 @@ export const EXTENSION = '.def';
 export const STRUCTURE_FILES: Record<string, string> = {};
 export const COMMENT = '//';
 export const INTERNAL = '__';
-export const LEAN_HEADER_GUARD = '#ifndef LEAN_SYMBOLS_HEADER\n';
+export const BUILDING_SYMBOLS_GUARD = 'BUILDING_SYMBOLS_LIB';
 // Read Definition File
 export function readDefinition(name: string) {
     if (!STRUCTURE_FILES[name]) {
@@ -117,20 +117,23 @@ export function getDataDir() {
     return path.join(__dirname, '..', 'data');
 }
 // Format File From Data Directory
-export function formatFile(file: string, options: Record<string, string>) {
+export function formatFile(file: string, options: Record<string, string>, includeOtherFiles = true) {
-    // Include Other Files
+    const newOptions = Object.assign({}, options);
     const dataDir = getDataDir();
-    const otherFiles = fs.readdirSync(dataDir);
+    // Include Other Files
-    for (let otherFile of otherFiles) {
+    if (includeOtherFiles) {
-        otherFile = path.join(dataDir, otherFile);
+        const otherFiles = fs.readdirSync(dataDir);
-        options[`include ${otherFile}`] = fs.readFileSync(otherFile, 'utf8');
+        for (const otherFile of otherFiles) {
+            newOptions[`include ${otherFile}`] = formatFile(otherFile, options, false);
+        }
     }
     // Format
     file = path.join(dataDir, file);
     let data = fs.readFileSync(file, 'utf8');
-    for (const key in options) {
+    for (const key in newOptions) {
-        const value = options[key];
+        let value = newOptions[key];
         if (value) {
+            value = value.trim();
             data = data.replace(`{{ ${key} }}`, value);
         }
     }

src/index.ts

@@ -1,6 +1,6 @@
 import * as fs from 'node:fs';
 import * as path from 'node:path';
-import { STRUCTURE_FILES, EXTENSION, formatFile, getDataDir, extendErrorMessage } from './common';
+import { STRUCTURE_FILES, EXTENSION, formatFile, getDataDir, extendErrorMessage, BUILDING_SYMBOLS_GUARD } from './common';
 import { getStructure } from './map';
 import { Struct } from './struct';
 
@@ -41,7 +41,7 @@ while (process.argv.length > 0) {
         const fullName = file.base;
         const name = file.name;
         // Store
-        if (name in STRUCTURE_FILES) {
+        if (STRUCTURE_FILES[name]) {
             throw new Error(`Multiple Definition Files Provided: ${fullName}`);
         }
         STRUCTURE_FILES[name] = filePath;
@@ -129,7 +129,7 @@ function makeHeaderPart() {
         try {
             structures += structure.generate();
         } catch (e) {
-            throw new Error(extendErrorMessage(e, 'Error Generating Header: ' + name));
+            throw new Error(extendErrorMessage(e, 'Generating Header: ' + name));
         }
         structures += '\n';
     }
@@ -155,7 +155,7 @@ function makeMainHeader(output: string) {
     // Main
     const main = makeHeaderPart().trim();
     // Write
-    const result = formatFile('out.h', {forwardDeclarations, extraHeaders, main, data: getDataDir()});
+    const result = formatFile('out.h', {BUILDING_SYMBOLS_GUARD, forwardDeclarations, extraHeaders, main, data: getDataDir()});
     fs.writeFileSync(output, result);
 }
 makeMainHeader(headerOutput);
@@ -182,14 +182,14 @@ function makeCompiledCode(outputDir: string) {
         try {
             declarations += structure.generateCode().trim();
         } catch (e) {
-            throw new Error(extendErrorMessage(e, 'Error Generating Code: ' + name));
+            throw new Error(extendErrorMessage(e, 'Generating Code: ' + name));
         }
         declarations += '\n';
 
         // Write
         const headerPath = fs.realpathSync(headerOutput);
         const main = declarations.trim();
-        const result = formatFile('out.cpp', {headerPath, main, data: getDataDir()});
+        const result = formatFile('out.cpp', {BUILDING_SYMBOLS_GUARD, headerPath, main, data: getDataDir()});
         const output = path.join(outputDir, name + '.cpp');
         fs.writeFileSync(output, result);
     }

src/method.ts

@@ -1,6 +1,11 @@
 import { INDENT, INTERNAL, formatType, toHex } from './common';
 
+// A Template Parameter So Each Template Instantiation Is Unique
+let nextDiscriminator = 0;
+
+// An Individual Method
 export class Method {
+    readonly #discriminator: number;
     readonly self: string;
     readonly shortName: string;
     readonly returnType: string;
@@ -11,6 +16,7 @@ export class Method {
 
     // Constructor
     constructor(self: string, name: string, returnType: string, args: string, address: number, isInherited: boolean, isStatic: boolean) {
+        this.#discriminator = nextDiscriminator++;
         this.self = self;
         this.shortName = name;
         this.returnType = returnType;
@@ -34,7 +40,7 @@ export class Method {
         return `${INDENT}${this.#getRawType()} *${this.shortName};\n`;
     }
     #getFullType() {
-        return `${INTERNAL}Function<${this.#getRawType()}>`;
+        return `${INTERNAL}Function<${this.#discriminator.toString()}, ${this.#getRawType()}>`;
     }
 
     // Typedefs
@@ -52,16 +58,14 @@ export class Method {
     generate(code: boolean, isVirtual: boolean, parentSelf?: string) {
         let out = '';
         out += 'extern ';
-        const type = this.#getFullType();
+        out += `${this.#getFullType()} *const ${this.getName()}`;
-        out += `${type} *const ${this.getName()}`;
         if (code) {
-            out += ` = new ${type}(${JSON.stringify(this.getName('::'))}, `;
+            out += ` = new ${this.#getFullType()}(${JSON.stringify(this.getName('::'))}, `;
-            out += `${INTERNAL}thunk<&${this.getName()}>, `;
             if (isVirtual) {
                 const parentMethod = parentSelf ? this.#getVirtualCall(parentSelf) : 'nullptr';
-                out += `&${this.#getVirtualCall()}, ${parentMethod}`;
+                out += `new ${INTERNAL}VirtualFunctionInfo(&${this.#getVirtualCall()}, (void *) ${parentMethod})`;
             } else {
-                out += `(${this.#getRawType()} *) ${toHex(this.address)}`;
+                out += `new ${INTERNAL}NormalFunctionInfo((${this.#getRawType()} *) ${toHex(this.address)})`;
             }
             out += ')';
         }

src/struct.ts

@@ -1,4 +1,4 @@
-import { INDENT, STRUCTURE_FILES, toHex, assertSize, INTERNAL, preventConstruction, LEAN_HEADER_GUARD } from './common';
+import { INDENT, STRUCTURE_FILES, toHex, assertSize, INTERNAL, preventConstruction, BUILDING_SYMBOLS_GUARD } from './common';
 import { Method } from './method';
 import { Property, StaticProperty } from './property';
 import { VTable } from './vtable';
@@ -71,7 +71,7 @@ export class Struct {
         this.#properties.push(property);
         // Add Dependency If Needed
         const type = property.rawType();
-        if (type in STRUCTURE_FILES) {
+        if (STRUCTURE_FILES[type]) {
             this.#addDependency(type);
         }
     }
@@ -165,7 +165,7 @@ export class Struct {
     }
     #generateMethods() {
         let out = '';
-        out += LEAN_HEADER_GUARD;
+        out += `#ifndef ${BUILDING_SYMBOLS_GUARD}\n`;
         // Normal Methods
         for (const method of this.#methods) {
             out += this.#generateMethod(method, false);
@@ -174,7 +174,9 @@ export class Struct {
         if (this.#vtable !== null) {
             const virtualMethods = this.#vtable.getMethods();
             for (const method of virtualMethods) {
-                out += this.#generateMethod(method, true);
+                if (method) {
+                    out += this.#generateMethod(method, true);
+                }
             }
         }
         // Allocation Method
@@ -223,7 +225,7 @@ export class Struct {
             }
         }
         out += typedefs;
-        out += LEAN_HEADER_GUARD;
+        out += `#ifndef ${BUILDING_SYMBOLS_GUARD}\n`;
         out += methodsOut;
         out += '#endif\n';
 

src/vtable.ts

@@ -1,4 +1,4 @@
-import { INDENT, LEAN_HEADER_GUARD, POINTER_SIZE, assertSize, getSelfArg, preventConstruction, toHex } from './common';
+import { BUILDING_SYMBOLS_GUARD, INDENT, POINTER_SIZE, assertSize, getSelfArg, preventConstruction, toHex } from './common';
 import { Method } from './method';
 import { Property } from './property';
 
@@ -7,9 +7,10 @@ export class VTable {
     readonly #self: string;
     #address: number | null;
     #size: number | null;
-    readonly #methods: Method[];
+    readonly #methods: (Method | undefined)[];
     readonly property: Property;
     #destructorOffset: number;
+    readonly #destructors: Method[];
 
     // Constructor
     constructor(self: string) {
@@ -18,6 +19,7 @@ export class VTable {
         this.#size = null;
         this.#methods = [];
         this.#destructorOffset = 0;
+        this.#destructors = [];
         // Create Property
         this.property = new Property(0, this.#getName() + ' *', 'vtable', this.#self);
     }
@@ -35,7 +37,7 @@ export class VTable {
     }
 
     // Add To VTable
-    #add(target: Method[], method: Method) {
+    #add(target: (Method | undefined)[], method: Method) {
         // Check Offset
         const offset = method.address;
         if ((offset % POINTER_SIZE) !== 0) {
@@ -43,7 +45,7 @@ export class VTable {
         }
         // Add
         const index = offset / POINTER_SIZE;
-        if (index in target) {
+        if (target[index]) {
             throw new Error(`Duplicate Virtual Method At Offset: ${toHex(offset)}`);
         }
         target[index] = method;
@@ -80,8 +82,15 @@ export class VTable {
         // Add Destructors (https://stackoverflow.com/a/17960941)
         const destructor_return = `${this.#self} *`;
         const destructor_args = `(${getSelfArg(this.#self)})`;
-        this.#add(out, new Method(this.#self, 'destructor_complete', destructor_return, destructor_args, 0x0 + this.#destructorOffset, false, false));
+        if (this.#destructors.length === 0) {
-        this.#add(out, new Method(this.#self, 'destructor_deleting', destructor_return, destructor_args, 0x4 + this.#destructorOffset, false, false));
+            this.#destructors.push(
+                new Method(this.#self, 'destructor_complete', destructor_return, destructor_args, 0x0 + this.#destructorOffset, false, false),
+                new Method(this.#self, 'destructor_deleting', destructor_return, destructor_args, 0x4 + this.#destructorOffset, false, false)
+            );
+        }
+        for (const destructor of this.#destructors) {
+            this.#add(out, destructor);
+        }
         // Return
         return out;
     }
@@ -119,13 +128,15 @@ export class VTable {
         let typedefs = '';
         let methodsOut = '';
         for (const info of methods) {
-            typedefs += info.generateTypedefs();
+            if (info) {
-            if (this.canGenerateWrappers()) {
+                typedefs += info.generateTypedefs();
-                methodsOut += info.generate(false, true);
+                if (this.canGenerateWrappers()) {
+                    methodsOut += info.generate(false, true);
+                }
             }
         }
         out += typedefs;
-        out += LEAN_HEADER_GUARD;
+        out += `#ifndef ${BUILDING_SYMBOLS_GUARD}\n`;
         out += methodsOut;
         out += '#endif\n';
 
@@ -176,7 +187,9 @@ export class VTable {
         if (this.canGenerateWrappers()) {
             const methods = this.getMethods();
             for (const info of methods) {
-                out += info.generate(true, true, this.#getParentSelf(info, directParent));
+                if (info) {
+                    out += info.generate(true, true, this.#getParentSelf(info, directParent));
+                }
             }
         }