From f05e96c65fda212964e4f223309dcd216121c497 Mon Sep 17 00:00:00 2001
From: Christoffer Winterkvist <christoffer@winterkvist.com>
Date: Wed, 27 Mar 2019 22:15:13 +0100
Subject: [PATCH] Fix injecting Swift classes (#120)

* Update expression in loadAndInject

This is done to match the new format when grep-ing classes.

* Refactor inject(tmpfile: String)

Add new condition to match swift classes.

Co-Authored-By: John Holdsworth <johnno1962@users.noreply.github.com>

* Bump version number to 1.5.1

* Fix log statement

Co-Authored-By: John Holdsworth <johnno1962@users.noreply.github.com>

* Add code comment about Swift metadata

Co-Authored-By: John Holdsworth <johnno1962@users.noreply.github.com>

* Include instructions for when to turn off code coverage.

* Update README.md

* Bump CFBundleVersion to 1616
---
 InjectionBundle/SwiftEval.swift      |  8 ++++++--
 InjectionBundle/SwiftInjection.swift | 10 +++++++---
 InjectionIII/Info.plist              |  4 ++--
 README.md                            |  2 +-
 4 files changed, 16 insertions(+), 8 deletions(-)

diff --git a/InjectionBundle/SwiftEval.swift b/InjectionBundle/SwiftEval.swift
index 71d6f2a8..847ff243 100644
--- a/InjectionBundle/SwiftEval.swift
+++ b/InjectionBundle/SwiftEval.swift
@@ -371,7 +371,11 @@ public class SwiftEval: NSObject {
         print("💉 Loading .dylib ...")
         // load patched .dylib into process with new version of class
         guard let dl = dlopen("\(tmpfile).dylib", RTLD_NOW) else {
-            throw evalError("dlopen() error: \(String(cString: dlerror()))")
+            let error = String(cString: dlerror())
+            if error.contains("___llvm_profile_runtime") {
+                print("💉 Loading .dylib has failed, try turning off collection of test coverage in your scheme")
+            }
+            throw evalError("dlopen() error: \(error)")
         }
         print("💉 Loaded .dylib - Ignore any duplicate class warning ^")
 
@@ -396,7 +400,7 @@ public class SwiftEval: NSObject {
             try injectGenerics(tmpfile: tmpfile, handle: dl)
 
             guard shell(command: """
-                \(xcodeDev)/Toolchains/XcodeDefault.xctoolchain/usr/bin/nm \(tmpfile).o | grep -E ' S _OBJC_CLASS_\\$_| _(_T0|\\$S).*CN$' | awk '{print $3}' >\(tmpfile).classes
+                \(xcodeDev)/Toolchains/XcodeDefault.xctoolchain/usr/bin/nm \(tmpfile).o | grep -E ' S _OBJC_CLASS_\\$_| _(_T0|\\$S|\\$s).*CN$' | awk '{print $3}' >\(tmpfile).classes
                 """) else {
                 throw evalError("Could not list class symbols")
             }
diff --git a/InjectionBundle/SwiftInjection.swift b/InjectionBundle/SwiftInjection.swift
index 3ba8d387..2bccfdff 100644
--- a/InjectionBundle/SwiftInjection.swift
+++ b/InjectionBundle/SwiftInjection.swift
@@ -115,8 +115,12 @@ public class SwiftInjection: NSObject {
             let classMetadata = unsafeBitCast(newClass, to: UnsafeMutablePointer<ClassMetadataSwift>.self)
 
             // Is this a Swift class?
-            if (classMetadata.pointee.Data & 0x1) == 1 {
-                // Swift equivalent of Swizzling
+            // Reference: https://github.com/apple/swift/blob/master/include/swift/ABI/Metadata.h#L1195
+            let oldSwiftCondition = classMetadata.pointee.Data & 0x1 == 1
+            let newSwiftCondition = classMetadata.pointee.Data & 0x3 != 0
+            let isSwiftClass = newSwiftCondition || oldSwiftCondition
+            if isSwiftClass {
+              // Swift equivalent of Swizzling
                 if classMetadata.pointee.ClassSize != existingClass.pointee.ClassSize {
                     print("💉 ⚠️ Adding or removing methods on Swift classes is not supported. Your application will likely crash. ⚠️")
                 }
@@ -129,7 +133,7 @@ public class SwiftInjection: NSObject {
                 let vtableLength = Int(existingClass.pointee.ClassSize -
                     existingClass.pointee.ClassAddressPoint) - vtableOffset
 
-                print("💉 Injected '\(NSStringFromClass(oldClass))'")
+                print("💉 Injected '\(oldClass)'")
                 memcpy(byteAddr(existingClass) + vtableOffset,
                        byteAddr(classMetadata) + vtableOffset, vtableLength)
             }
diff --git a/InjectionIII/Info.plist b/InjectionIII/Info.plist
index 84f6a411..dc5ff1ac 100644
--- a/InjectionIII/Info.plist
+++ b/InjectionIII/Info.plist
@@ -17,9 +17,9 @@
 	<key>CFBundlePackageType</key>
 	<string>APPL</string>
 	<key>CFBundleShortVersionString</key>
-	<string>1.5</string>
+	<string>1.5.1</string>
 	<key>CFBundleVersion</key>
-	<string>1601</string>
+	<string>1616</string>
 	<key>LSApplicationCategoryType</key>
 	<string>public.app-category.developer-tools</string>
 	<key>LSMinimumSystemVersion</key>
diff --git a/README.md b/README.md
index 4530f8c0..f7be1038 100644
--- a/README.md
+++ b/README.md
@@ -57,7 +57,7 @@ from source you'll need to use:
     
 ### Available downloads
 
-| Xcode 9.3/4, Xcode 10 |
+| Xcode 10.1, Xcode 10.2 |
 | ------------- |
 | [Mac app store](https://itunes.apple.com/app/injectioniii/id1380446739?mt=12) |