Add ITKAddSuperMethod and new generics

steipete · steipete · Jun 15, 2020 · Jun 6, 2020 · Jun 6, 2020 · Jun 6, 2020
commit eadb0734a479f8eec6e0fca087eede84cf827658
diff --git a/InterposeKit.xcodeproj/project.pbxproj b/InterposeKit.xcodeproj/project.pbxproj
diff --git a/InterposeKit.xcodeproj/xcshareddata/xcschemes/InterposeKit.xcscheme b/InterposeKit.xcodeproj/xcshareddata/xcschemes/InterposeKit.xcscheme
@@ -28,14 +28,21 @@
       selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
       shouldUseLaunchSchemeArgsEnv = "YES"
       codeCoverageEnabled = "YES">
+      <AdditionalOptions>
+         <AdditionalOption
+            key = "NSZombieEnabled"
+            value = "YES"
+            isEnabled = "YES">
+         </AdditionalOption>
+      </AdditionalOptions>
       <Testables>
          <TestableReference
             skipped = "NO">
             <BuildableReference
                BuildableIdentifier = "primary"
                BlueprintIdentifier = "78C39D762482CC7D00B46395"
-               BuildableName = "InterposeTests.xctest"
-               BlueprintName = "InterposeTests"
+               BuildableName = "InterposeKitTests.xctest"
+               BlueprintName = "InterposeKitTests"
                ReferencedContainer = "container:InterposeKit.xcodeproj">
             </BuildableReference>
          </TestableReference>

diff --git a/InterposeKit.xcodeproj/xcshareddata/xcschemes/InterposeTests.xcscheme b/InterposeKit.xcodeproj/xcshareddata/xcschemes/InterposeTests.xcscheme
@@ -15,8 +15,8 @@
             <BuildableReference
                BuildableIdentifier = "primary"
                BlueprintIdentifier = "78C39D762482CC7D00B46395"
-               BuildableName = "InterposeTests.xctest"
-               BlueprintName = "InterposeTests"
+               BuildableName = "InterposeKitTests.xctest"
+               BlueprintName = "InterposeKitTests"
                ReferencedContainer = "container:InterposeKit.xcodeproj">
             </BuildableReference>
          </BuildActionEntry>
@@ -52,8 +52,8 @@
          <BuildableReference
             BuildableIdentifier = "primary"
             BlueprintIdentifier = "78C39D762482CC7D00B46395"
-            BuildableName = "InterposeTests.xctest"
-            BlueprintName = "InterposeTests"
+            BuildableName = "InterposeKitTests.xctest"
+            BlueprintName = "InterposeKitTests"
             ReferencedContainer = "container:InterposeKit.xcodeproj">
          </BuildableReference>
       </MacroExpansion>

diff --git a/InterposeTestHost/AppDelegate.swift b/InterposeTestHost/AppDelegate.swift
@@ -1,37 +1,17 @@
-//
-//  AppDelegate.swift
-//  InterposeTestHost
-//
-//  Created by Peter Steinberger on 07.06.20.
-//  Copyright © 2020 PSPDFKit GmbH. All rights reserved.
-//
 
 import UIKit
 
 @UIApplicationMain
 class AppDelegate: UIResponder, UIApplicationDelegate {
-
-
+    var window: UIWindow?
 
     func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
-        // Override point for customization after application launch.
+        window = UIWindow(frame: UIScreen.main.bounds)
+        window!.rootViewController = UIStoryboard(name: "Main", bundle: nil).instantiateInitialViewController()!
+        (window!.rootViewController as? UINavigationController)?.topViewController?.title = "Test Host"
+        window!.makeKeyAndVisible()
         return true
     }
 
-    // MARK: UISceneSession Lifecycle
-
-    func application(_ application: UIApplication, configurationForConnecting connectingSceneSession: UISceneSession, options: UIScene.ConnectionOptions) -> UISceneConfiguration {
-        // Called when a new scene session is being created.
-        // Use this method to select a configuration to create the new scene with.
-        return UISceneConfiguration(name: "Default Configuration", sessionRole: connectingSceneSession.role)
-    }
-
-    func application(_ application: UIApplication, didDiscardSceneSessions sceneSessions: Set<UISceneSession>) {
-        // Called when the user discards a scene session.
-        // If any sessions were discarded while the application was not running, this will be called shortly after application:didFinishLaunchingWithOptions.
-        // Use this method to release any resources that were specific to the discarded scenes, as they will not return.
-    }
-
-
 }
 
diff --git a/InterposeTestHost/Base.lproj/Main.storyboard b/InterposeTestHost/Base.lproj/Main.storyboard
@@ -1,24 +1,44 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<document type="com.apple.InterfaceBuilder3.CocoaTouch.Storyboard.XIB" version="3.0" toolsVersion="13122.16" targetRuntime="iOS.CocoaTouch" propertyAccessControl="none" useAutolayout="YES" useTraitCollections="YES" useSafeAreas="YES" colorMatched="YES" initialViewController="BYZ-38-t0r">
+<document type="com.apple.InterfaceBuilder3.CocoaTouch.Storyboard.XIB" version="3.0" toolsVersion="16097" targetRuntime="iOS.CocoaTouch" propertyAccessControl="none" useAutolayout="YES" useTraitCollections="YES" useSafeAreas="YES" colorMatched="YES" initialViewController="1tn-ac-EBX">
+    <device id="retina6_1" orientation="portrait" appearance="light"/>
     <dependencies>
-        <plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="13104.12"/>
+        <deployment identifier="iOS"/>
+        <plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="16087"/>
         <capability name="Safe area layout guides" minToolsVersion="9.0"/>
         <capability name="documents saved in the Xcode 8 format" minToolsVersion="8.0"/>
     </dependencies>
     <scenes>
+        <!--Navigation Controller-->
+        <scene sceneID="Trk-wk-4or">
+            <objects>
+                <navigationController id="1tn-ac-EBX" sceneMemberID="viewController">
+                    <navigationBar key="navigationBar" contentMode="scaleToFill" insetsLayoutMarginsFromSafeArea="NO" id="1vj-TX-zC1">
+                        <rect key="frame" x="0.0" y="44" width="414" height="44"/>
+                        <autoresizingMask key="autoresizingMask"/>
+                    </navigationBar>
+                    <connections>
+                        <segue destination="6lZ-01-xub" kind="relationship" relationship="rootViewController" id="wKN-DH-MvS"/>
+                    </connections>
+                </navigationController>
+                <placeholder placeholderIdentifier="IBFirstResponder" id="TgX-rg-aXD" userLabel="First Responder" customClass="UIResponder" sceneMemberID="firstResponder"/>
+            </objects>
+            <point key="canvasLocation" x="801" y="133"/>
+        </scene>
         <!--View Controller-->
-        <scene sceneID="tne-QT-ifu">
+        <scene sceneID="Opn-j2-Tea">
             <objects>
-                <viewController id="BYZ-38-t0r" customClass="ViewController" customModuleProvider="target" sceneMemberID="viewController">
-                    <view key="view" contentMode="scaleToFill" id="8bC-Xf-vdC">
-                        <rect key="frame" x="0.0" y="0.0" width="375" height="667"/>
+                <viewController id="6lZ-01-xub" sceneMemberID="viewController">
+                    <view key="view" contentMode="scaleToFill" id="31n-bO-IqB">
+                        <rect key="frame" x="0.0" y="0.0" width="414" height="896"/>
                         <autoresizingMask key="autoresizingMask" widthSizable="YES" heightSizable="YES"/>
-                        <color key="backgroundColor" xcode11CocoaTouchSystemColor="systemBackgroundColor" cocoaTouchSystemColor="whiteColor"/>
-                        <viewLayoutGuide key="safeArea" id="6Tk-OE-BBY"/>
+                        <color key="backgroundColor" systemColor="systemBackgroundColor" cocoaTouchSystemColor="whiteColor"/>
+                        <viewLayoutGuide key="safeArea" id="DIt-AO-3qQ"/>
                     </view>
+                    <navigationItem key="navigationItem" id="9eb-Ye-odT"/>
                 </viewController>
-                <placeholder placeholderIdentifier="IBFirstResponder" id="dkx-z0-nzr" sceneMemberID="firstResponder"/>
+                <placeholder placeholderIdentifier="IBFirstResponder" id="Yxf-nQ-wKc" userLabel="First Responder" customClass="UIResponder" sceneMemberID="firstResponder"/>
             </objects>
+            <point key="canvasLocation" x="800" y="777"/>
         </scene>
     </scenes>
 </document>
diff --git a/InterposeTestHost/Info.plist b/InterposeTestHost/Info.plist
@@ -22,25 +22,6 @@
 	<string>public.app-category.developer-tools</string>
 	<key>LSRequiresIPhoneOS</key>
 	<true/>
-	<key>UIApplicationSceneManifest</key>
-	<dict>
-		<key>UIApplicationSupportsMultipleScenes</key>
-		<false/>
-		<key>UISceneConfigurations</key>
-		<dict>
-			<key>UIWindowSceneSessionRoleApplication</key>
-			<array>
-				<dict>
-					<key>UISceneConfigurationName</key>
-					<string>Default Configuration</string>
-					<key>UISceneDelegateClassName</key>
-					<string>$(PRODUCT_MODULE_NAME).SceneDelegate</string>
-					<key>UISceneStoryboardFile</key>
-					<string>Main</string>
-				</dict>
-			</array>
-		</dict>
-	</dict>
 	<key>UILaunchStoryboardName</key>
 	<string>LaunchScreen</string>
 	<key>UIMainStoryboardFile</key>

diff --git a/InterposeTestHost/SceneDelegate.swift b/InterposeTestHost/SceneDelegate.swift
diff --git a/Package.swift b/Package.swift
@@ -1,4 +1,4 @@
-// swift-tools-version:5.2
+// swift-tools-version:5.0
 
 import PackageDescription
 
@@ -11,18 +11,11 @@ let package = Package(
        .watchOS(.v5)
      ],
     products: [
-        // Products define the executables and libraries produced by a package, and make them visible to other packages.
-        .library(
-            name: "InterposeKit",
-            targets: ["InterposeKit"]),
+        .library(name: "InterposeKit",targets: ["InterposeKit"]),
     ],
     targets: [
-        // Targets are the basic building blocks of a package. A target can define a module or a test suite.
-        // Targets can depend on other targets in this package, and on products in packages which this package depends on.
-        .target(
-            name: "InterposeKit"),
-        .testTarget(
-            name: "InterposeKitTests",
-            dependencies: ["InterposeKit"]),
+        .target(name: "ITKAddSuperMethod"),
+        .target(name: "InterposeKit", dependencies: ["ITKAddSuperMethod"]),
+        .testTarget(name: "InterposeKitTests", dependencies: ["InterposeKit"]),
     ]
 )
diff --git a/Sources/ITKAddSuperMethod/ITKAddSuperMethod.h b/Sources/ITKAddSuperMethod/ITKAddSuperMethod.h
@@ -0,0 +1,20 @@
+//
+//  ITKAddSuperMethod.h
+//  InterposeKit
+//
+//  Created by Peter Steinberger on 08.06.20.
+//
+
+#import <Foundation/Foundation.h>
+
+NS_ASSUME_NONNULL_BEGIN
+
+/**
+ Adds an empty super implementation instance method to klass.
+ If a method already exists, this will return NO.
+
+ @note This uses inline assembly to forward the parameters to objc_msgSendSuper.
+*/
+BOOL IKTAddSuperImplementationToClass(Class klass, SEL selector);
+
+NS_ASSUME_NONNULL_END
diff --git a/Sources/ITKAddSuperMethod/ITKAddSuperMethod.m b/Sources/ITKAddSuperMethod/ITKAddSuperMethod.m
@@ -0,0 +1,124 @@
+//
+//  ITKAddSuperMethod.m
+//  InterposeKit
+//
+//  Created by Peter Steinberger on 08.06.20.
+//  Copyright © 2020 PSPDFKit GmbH. All rights reserved.
+//
+
+#import "ITKAddSuperMethod.h"
+
+@import ObjectiveC.message;
+@import ObjectiveC.runtime;
+
+NS_ASSUME_NONNULL_BEGIN
+
+void msgSendSuperTrampoline(void);
+
+#if defined(__arm64__)
+
+__attribute__((__naked__))
+void msgSendSuperTrampoline(void) {
+    asm volatile (
+                  " sub    sp, sp, #48             ; =48  \n\t"
+                  " stp    x29, x30, [sp, #32]     ; 16-byte Folded Spill  \n\t"
+                  " add    x29, sp, #32            ; =32  \n\t"
+                  " stur    x0, [x29, #-8]  \n\t"
+                  " str    x1, [sp, #16]  \n\t"
+                  " ldur    x8, [x29, #-8]  \n\t"
+                  " str    x8, [sp]  \n\t"
+                  " ldur    x0, [x29, #-8] \n\t"
+                  " bl    _objc_opt_class \n\t"
+                  " str    x0, [sp, #8] \n\t"
+                  " ldr    x1, [sp, #16] \n\t"
+                  " mov    x0, sp \n\t"
+                  " bl    _objc_msgSendSuper  \n\t"
+                  " mov    x29, x29    ; marker for objc_retainAutoreleaseReturnValue \n\t"
+                  " ldp    x29, x30, [sp, #32]     ; 16-byte Folded Reload \n\t"
+                  " add    sp, sp, #48             ; =48 \n\t"
+                  " ret \n\t"
+                  : : : "x0", "x1");
+}
+
+#elif defined(__x86_64__)
+
+__attribute__((__naked__))
+void msgSendSuperTrampoline(void) {
+    asm volatile (
+                  "pushq   %%rbp                 # push frame pointer \n\t"
+                  "movq    %%rsp, %%rbp          # set stack to frame pointer \n\t"
+                  "subq    $32, %%rsp            # reserve 32 byte on the stack (need 16 byte alignment) \n\t"
+                  "movq    %%rdi, -8(%%rbp)      # copy self to stack[1] \n\t"
+                  "movq    %%rsi, -16(%%rbp)     # copy _cmd to stack[2] \n\t"
+                  "movq    -8(%%rbp), %%rax      # load self to rax \n\t"
+                  "movq    %%rax, -32(%%rbp)     # store self to stack[4] \n\t"
+                  "movq    -8(%%rbp), %%rdi      # load self to rdi-first parameter \n\t"
+                  "callq    _objc_opt_class      # call objc_opt_class(self) \n\t"
+                  "#movq    %%rax, %%rdi          # move result to rdi-first parameter  \n\t"
+                  "#callq    _class_getSuperclass # call class_getSuperclass(self) \n\t"
+                  "movq    %%rax, -24(%%rbp)     # move result to stack[3] \n\t"
+                  "movq    -16(%%rbp), %%rsi     # copy _cmd to #rsi \n\t"
+                  "xorl    %%ecx, %%ecx          # nill out rcx?  \n\t"
+                  "leaq    -32(%%rbp), %%rdi     # load address of objc_super struct to rdi-first param \n\t"
+                  "movb    %%cl, %%al            # nill ot rax/rcx? \n\t"
+                  "callq _objc_msgSendSuper     # regular call \n\t"
+                  "movq    %%rax, %%rdi \n\t"
+                  "addq    $32, %%rsp            # remove 32 byte from stack \n\t"
+                  "popq    %%rbp                 # pop frame pointer \n\t"
+                  "retq\n\r"
+                  : : : "rsi", "rdi");
+}
+
+#endif
+
+typedef NS_ENUM(NSInteger, DispatchMode) {
+    DispatchMode_Normal,
+    DispatchMode_Stret,
+};
+
+static DispatchMode IKTGetDispatchMode(const char * typeEncoding) {
+    DispatchMode dispatchMode = DispatchMode_Normal;
+#if defined (__arm64__)
+    // ARM64 doesn't use stret dispatch
+#elif defined (__x86_64__)
+    // On x86-64, stret dispatch is used whenever return type doesn't fit into two registers
+    NSUInteger returnTypeActualSize = 0;
+    NSGetSizeAndAlignment(typeEncoding, &returnTypeActualSize, NULL);
+    dispatchMode = returnTypeActualSize > (sizeof(void *) * 2) ? DispatchMode_Stret : DispatchMode_Normal;
+#else
+#error - Unknown architecture
+#endif
+    return dispatchMode;
+}
+
+BOOL IKTAddSuperImplementationToClass(Class klass, SEL selector) {
+    Class originalClass = klass;
+
+    Class superClass = class_getSuperclass(originalClass);
+    if (superClass == nil) {
+        return NO;
+    }
+    Method method = class_getInstanceMethod(superClass, selector);
+    if (method == NULL) {
+        [NSException raise:NSInternalInconsistencyException
+                    format:@"No dynamically dispatched method with selector %@ is available on any of the superclasses of %@",
+         NSStringFromSelector(selector), NSStringFromClass(originalClass)];
+        return NO;
+    }
+    const char *typeEncoding = method_getTypeEncoding(method);
+    // Need to write asm for x64
+    __unused DispatchMode dispatchMode = IKTGetDispatchMode(typeEncoding);
+    BOOL methodAdded = class_addMethod(klass,
+                                       selector,
+                                       msgSendSuperTrampoline,
+                                       typeEncoding);
+    if (!methodAdded) {
+        NSLog(@"Failed to add method for selector %@ to class %@",
+              NSStringFromSelector(selector),
+              NSStringFromClass(klass));
+    }
+
+    return methodAdded;
+}
+
+NS_ASSUME_NONNULL_END