find /Applications/Xcode6-Beta.app/Contents/ -name "*swift*"
/Applications/Xcode6-Beta.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/swift /Applications/Xcode6-Beta.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/swift-demangle /Applications/Xcode6-Beta.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/swift-ide-test /Applications/Xcode6-Beta.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/swift-stdlib-tool /Applications/Xcode6-Beta.app/Contents/SharedFrameworks/LLDB.framework/Versions/A/Resources/repl_swift /Applications/Xcode6-Beta.app/Contents//Developer/Toolchains/XcodeDefault.xctoolchain/usr/share/man/man1/swift.1
swift(1) Swift Documentation swift(1) NAME swift - <strong>the amazingly new programming language</strong> SYNOPSIS swift [-emit-object|-emit-assembly|-emit-library|-i] [-help] -o output-file input-filenames The full list of supported options is available via "swift -help". DESCRIPTION Swift is a new, high performance systems programming language. It has a clean and modern syntax, and offers seamless access to existing C and Objective-C code and frameworks, and is memory safe (by default). Although inspired by Objective-C and many other languages, Swift is not itself a C-derived language. As a complete and independent language, Swift packages core features like flow control, data structures, and functions, with high-level constructs like objects, protocols, closures, and generics. Swift embraces modules, eliminating the need for headers and the code duplication they entail. 2014-05-17 swift(1)
OVERVIEW: Swift compiler USAGE: swift [options] <inputs> MODES: -dump-ast Parse and type-check input file(s) and dump AST(s) -dump-parse Parse input file(s) and dump AST(s) -emit-assembly Emit assembly file(s) (-S) -emit-bc Emit LLVM BC file(s) -emit-executable Emit a linked executable -emit-ir Emit LLVM IR file(s) -emit-library Emit a linked library -emit-object Emit object file(s) (-c) -emit-silgen Emit raw SIL file(s) -emit-sil Emit canonical SIL file(s) -integrated-repl Integrated REPL mode -i Immediate mode -lldb-repl LLDB-enhanced REPL mode -parse Parse input file(s) -print-ast Parse and type-check input file(s) and pretty print AST(s) -repl REPL mode OPTIONS: -application-extension Restrict code to those available for App Extensions -arch <arch> Compile for architecture <arch> -assert-config <value> Specify the assert_configuration replacement. Possible values are Debug, Release, Replacement. -D <value> Specifies one or more build configuration options -emit-dependencies Emit Make-compatible dependencies files -emit-module-path <path> Emit an importable module to <path> -emit-module Emit an importable module -emit-objc-header-path <path> Emit an Objective-C header file to <path> -emit-objc-header Emit an Objective-C header file -framework <value> Specifies a framework which should be linked against -F <value> Add directory to framework search path -g Emit debug info -help Display available options -import-underlying-module Implicitly imports the Objective-C half of a module -I <value> Add directory to the import search path -j <n> Number of commands to execute in parallel -L <value> Add directory to library link search path -l<value> Specifies a library which should be linked against -module-cache-path <value> Specifies the Clang module cache path -module-link-name <value> Library to link against when using this module -module-name <value> Name of the module to build -nostdimport Don't search the standard library import path for modules -output-file-map <path> A file which specifies the location of outputs -o <file> Write output to <file> -parse-as-library Parse the input file(s) as libraries, not scripts -parse-sil Parse the input file as SIL code, not Swift source -save-temps Save intermediate compilation results -sdk <sdk> Compile against <sdk> -serialize-diagnostics Serialize diagnostics in a binary format -target-cpu <value> Generate code for a particular CPU variant -target-feature [+-]<feature-name> Generate code with a particular CPU feature enabled or disabled -target <value> Generate code for the given target -version Print version information and exit -v Show commands to run and use verbose output -Xcc <arg> Pass <arg> to the C/C++/Objective-C compiler -Xfrontend <arg> Pass <arg> to the Swift frontend -Xlinker <value> Specifies an option which should be passed to the linker -Xllvm <arg> Pass <arg> to LLVM.
这么多参数到底怎么用呢?!我们一起来看看 xcode 是怎么使用的。
打开xcode6新建一个空工程,取名“FuckSwift”:
因此,在iOS8之下的设备上,程序打包的时候带上了必要的运行库。对于iOS8,目前还没法解开 dyld cache 也就无法知道设备上是否带了这些库,不过应该会带。
接上文,我们建立测试工程的目的是为了看看 xcode 如何使用 swift 编译工具,xcoce编译时的相关参数如下:
/Applications/Xcode6-Beta.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/swift -target armv7-apple-ios5.0 -module-name FuckSwift -O0 -sdk /Applications/Xcode6-Beta.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS8.0.sdk -g -module-cache-path /Users/proteas/Library/Developer/Xcode/DerivedData/ModuleCache -I /Users/proteas/Library/Developer/Xcode/DerivedData/FuckSwift-czflmbyelvdrnvaxblvpkcrhfbie/Build/Products/Debug-iphoneos -F /Users/proteas/Library/Developer/Xcode/DerivedData/FuckSwift-czflmbyelvdrnvaxblvpkcrhfbie/Build/Products/Debug-iphoneos -parse-as-library -c -j8 /Users/proteas/Desktop/FuckSwift/FuckSwift/AppDelegate.swift -output-file-map /Users/proteas/Library/Developer/Xcode/DerivedData/FuckSwift-czflmbyelvdrnvaxblvpkcrhfbie/Build/Intermediates/FuckSwift.build/Debug-iphoneos/FuckSwift.build/Objects-normal/armv7/FuckSwift-OutputFileMap.json -serialize-diagnostics -emit-dependencies -emit-module -emit-module-path /Users/proteas/Library/Developer/Xcode/DerivedData/FuckSwift-czflmbyelvdrnvaxblvpkcrhfbie/Build/Intermediates/FuckSwift.build/Debug-iphoneos/FuckSwift.build/Objects-normal/armv7/FuckSwift.swiftmodule -Xcc -iquote -Xcc /Users/proteas/Library/Developer/Xcode/DerivedData/FuckSwift-czflmbyelvdrnvaxblvpkcrhfbie/Build/Intermediates/FuckSwift.build/Debug-iphoneos/FuckSwift.build/FuckSwift-generated-files.hmap -Xcc -I/Users/proteas/Library/Developer/Xcode/DerivedData/FuckSwift-czflmbyelvdrnvaxblvpkcrhfbie/Build/Intermediates/FuckSwift.build/Debug-iphoneos/FuckSwift.build/FuckSwift-own-target-headers.hmap -Xcc -I/Users/proteas/Library/Developer/Xcode/DerivedData/FuckSwift-czflmbyelvdrnvaxblvpkcrhfbie/Build/Intermediates/FuckSwift.build/Debug-iphoneos/FuckSwift.build/FuckSwift-all-target-headers.hmap -Xcc -iquote -Xcc /Users/proteas/Library/Developer/Xcode/DerivedData/FuckSwift-czflmbyelvdrnvaxblvpkcrhfbie/Build/Intermediates/FuckSwift.build/Debug-iphoneos/FuckSwift.build/FuckSwift-project-headers.hmap -Xcc -I/Users/proteas/Library/Developer/Xcode/DerivedData/FuckSwift-czflmbyelvdrnvaxblvpkcrhfbie/Build/Products/Debug-iphoneos/include -Xcc -I/Applications/Xcode6-Beta.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/include -Xcc -I/Users/proteas/Library/Developer/Xcode/DerivedData/FuckSwift-czflmbyelvdrnvaxblvpkcrhfbie/Build/Intermediates/FuckSwift.build/Debug-iphoneos/FuckSwift.build/DerivedSources/armv7 -Xcc -I/Users/proteas/Library/Developer/Xcode/DerivedData/FuckSwift-czflmbyelvdrnvaxblvpkcrhfbie/Build/Intermediates/FuckSwift.build/Debug-iphoneos/FuckSwift.build/DerivedSources -Xcc -DDEBUG=1 -emit-objc-header -emit-objc-header-path /Users/proteas/Library/Developer/Xcode/DerivedData/FuckSwift-czflmbyelvdrnvaxblvpkcrhfbie/Build/Intermediates/FuckSwift.build/Debug-iphoneos/FuckSwift.build/Objects-normal/armv7/FuckSwift-Swift.h
swift -target armv7-apple-ios5.0 -module-name FuckSwift -O0 -sdk iPhoneOS8.0.sdk -g -module-cache-path ModuleCache -I Debug-iphoneos -F Debug-iphoneos -parse-as-library -c -j8 AppDelegate.swift -output-file-map FuckSwift-OutputFileMap.json -serialize-diagnostics -emit-dependencies -emit-module -emit-module-path FuckSwift.swiftmodule -Xcc -iquote -Xcc FuckSwift-generated-files.hmap -Xcc -IFuckSwift-own-target-headers.hmap -Xcc -IFuckSwift-all-target-headers.hmap -Xcc -iquote -Xcc FuckSwift-project-headers.hmap -Xcc -Iinclude -Xcc -I/usr/include -Xcc -Iarmv7 -Xcc -IDerivedSources -Xcc -DDEBUG=1 <strong>-emit-objc-header -emit-objc-header-path FuckSwift-Swift.h</strong>
这样就相对清晰了。这里面的参数大家可以对照上述的帮助查看,这里我们一起看两点:
1、Xcc <arg>:Pass <arg> to the C/C++/Objective-C compiler,这里我们可以得到:swift代码很可能最终被转变成C/C++/Objective-C代码进行静态编译。
2、会生成FuckSwift-Swift.h头文件,对比下这个文件与swift文件。
@UIApplicationMain class AppDelegate: UIResponder, UIApplicationDelegate { var window: UIWindow? func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: NSDictionary?) -> Bool { self.window = UIWindow(frame: UIScreen.mainScreen().bounds) self.window!.backgroundColor = UIColor.whiteColor() self.window!.makeKeyAndVisible() return true } func applicationWillResignActive(application: UIApplication) { } func applicationDidEnterBackground(application: UIApplication) { } func applicationWillEnterForeground(application: UIApplication) { } func applicationDidBecomeActive(application: UIApplication) { } func applicationWillTerminate(application: UIApplication) { } }
SWIFT_CLASS("_TtC9FuckSwift11AppDelegate") @interface AppDelegate : UIResponder <UIApplicationDelegate> @property (nonatomic) UIWindow * window; - (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions; - (void)applicationWillResignActive:(UIApplication *)application; - (void)applicationDidEnterBackground:(UIApplication *)application; - (void)applicationWillEnterForeground:(UIApplication *)application; - (void)applicationDidBecomeActive:(UIApplication *)application; - (void)applicationWillTerminate:(UIApplication *)application; - (instancetype)init OBJC_DESIGNATED_INITIALIZER; @end
可以看到swift程序是被转换了的,但是是不是转换成了Objective-C程序呢?还需要进一步分析。
打开IDA,加载测试程序的MachO:
我们重点看下函数窗口:
从函数名上我们可以得到如下结论:
1、可以看到函数名被“改编”了。
2、swift代码并不是被简单得编译成了ObjC代码
3、swift代码最终被编译成了纯C代码,相对于ObjC来说省去了运行时查表进行函数调用的开销,执行效率应该比ObjC要高。
4、从文档上看swfit相对于ObjC来说是更加动态的语言,开发效率也应该比ObjC高
5、对于越狱开发来说,我们只要像Hook C函数那样来Hook swift 函数就可以了,因此MobileSubstrate还是可以工作的。
6、生成的代码还是要遵循 ARM 的ABI标准
就像C++的名称改编一样,改编后的名称虽然可以手工还原但是太麻烦,最好找到工具来做这一件事。前文,我们在查找swift相关的文件时看到一个工具:swift-demangle,下面我们就用它来demangle改编后的名称,看看可以得到什么。
首先,我们切换命令行到xcode6的命令行工具:
sudo xcode-select --switch /Applications/Xcode6-Beta.app/Contents/Developer
USAGE: swift-demangle [options] [mangled name...] OPTIONS: -compact - Compact mode (only emit the demangled names) -expand - Expand mode (show node structure of the demangling) -help - Display available options (-help-hidden for more) -no-sugar - No sugar mode (disable common language idioms such as ? and [] from the output) -tree-only - Tree-only mode (do not show the demangled string) -version - Display the version of this program
__TToFC9FuckSwift11AppDelegate26applicationDidBecomeActivefS0_FCSo13UIApplicationT_
xcrun swift-demangle "__TToFC9FuckSwift11AppDelegate26applicationDidBecomeActivefS0_FCSo13UIApplicationT_"
_TToFC9FuckSwift11AppDelegate26applicationDidBecomeActivefS0_FCSo13UIApplicationT_ ---> @objc FuckSwift.AppDelegate.applicationDidBecomeActive (FuckSwift.AppDelegate)(ObjectiveC.UIApplication) -> ()
可以看到函数被还原。
到这里我们停下,看看swift对越狱开发的影响:
1、目前无法使用class-dump得到ObjC的头文件。
2、MobileSubstrate应该还可以正常工作。
3、可以使用demangle工具还原函数名,后期这部分工作IDA可能会自动支持。
总之,对越狱开发的流程会稍微有影响,针对应用的越狱开发还可以存在。
下面我们看看命令行工具swift-ide-test的参数:
OVERVIEW: Swift IDE Test USAGE: swift-ide-test [options] [input files...] OPTIONS: -D=<string> - Build configurations -F=<string> - add a directory to the framework search path -I=<string> - add a directory to the import search path -annotate-print - Annotate AST printing -code-completion-diagnostics - Print compiler diagnostics while doing code completion -code-completion-token=<string> - Code completion token name -comments-xml-schema=<string> - Filename of the RelaxNG schema for documentation comments -enable-objc-factory-method-constructors - Implicitly import Objective-C factory methods as initializers -enable-objc-implicit-properties - Implicitly import Objective-C getter/setter pairs as properties -explode-pattern-binding-decls - Separate pattern binding decls into individual var decls -fatal-assembler-warnings - Consider warnings as error -fully-qualified-types - Print fully qualified types -fully-qualified-types-if-ambiguous - Print types fully-qualified if they would be ambiguous otherwise -function-definitions - Print function bodies -help - Display available options (-help-hidden for more) -implicit-objc-with - Make the "with" implicit in initializers -import-objc-header=<string> - header to implicitly import -module-cache-path=<string> - Clang module cache path -module-print-hidden - Print non-exported imported or submodules -module-print-skip-overlay - Skip Swift overlay modules -module-print-submodules - Recursively print submodules -module-to-print=<string> - Name of the module to print -objc-bridge-dictionary - Bridge Dictionary<K, V> to NSDictionary -prefer-type-repr - When printing types, prefer printing TypeReprs -print-after-all - Print IR after each pass -print-before-all - Print IR before each pass Mode: -code-completion - Perform code completion -repl-code-completion - Perform REPL-style code completion -syntax-coloring - Perform syntax coloring -structure - Perform document structure annotation -annotate - Perform semantic annotation -test-input-complete - Check if input source is complete -print-ast-not-typechecked - Print the non-typechecked AST -print-ast-typechecked - Print the typechecked AST -print-module - Print visible declarations in a module -print-types - Print types of all subexpressions and declarations in the AST -print-comments - Print documentation comments attached to decls -print-module-comments - Given a module, print documentation comments attached to decls -print-module-imports - Recursively print all imports visible from a particular module -print-usrs - Print USRs for all decls -parse-rest - Parse a ReST file -print-implicit-attrs - Print implicit attributes -print-regular-comments - Print regular comments from clang module headers -print-stats - Print statistics -sdk=<string> - path to the SDK to build against -skip-private-stdlib-decls - Don't print declarations that start with '_' -skip-unavailable - Don't print unavailable declarations -source-filename=<string> - Name of the source file -split-objc-selectors - Split Objective-C selectors -stats - Enable statistics output from program (available with Asserts) -synthesize-sugar-on-types - Always print Array and Optional with sugar -target=<string> - target triple -terminal - Use terminal color for source annotations -time-passes - Time each pass, printing elapsed time for each on exit -typecheck - Type check the AST -version - Display the version of this program
从参数上看,这很可能是xcode的内部工具,用来做代码完成与检查的。这里不具体分析,感兴趣的兄弟可以自己试试。
下面我们继续回到 swift 工具上,首先看看parse的输出,执行如下命令:
xcrun swift AppDelegate.swift -dump-parse
(source_file (import_decl UIKit') (class_decl "AppDelegate" type='<null type>' inherits: <null>, <null> (pattern_binding_decl (pattern_typed (pattern_named 'window') )) (var_decl "window" type='<null type>' storage_kind='stored') (func_decl "application(_:didFinishLaunchingWithOptions:)" type='<null type>' (body_params (pattern_typed implicit (pattern_named implicit 'self')) (pattern_tuple (pattern_typed (pattern_named 'application') (type_ident (component id='UIApplication' bind=none))) (pattern_typed (pattern_named 'launchOptions') ))) (result (type_ident (component id='Bool' bind=none))) (brace_stmt (sequence_expr type='<null>' (unresolved_dot_expr type='<null>' field 'window' (declref_expr type='<null>' decl=AppDelegate.(file).AppDelegate.func decl.self@AppDelegate.swift:17:10 specialized=yes)) (assign_expr (**NULL EXPRESSION**) (**NULL EXPRESSION**)) (call_expr type='<null>' (unresolved_decl_ref_expr type='<null>' name=UIWindow specialized=no) (tuple_expr type='<null>' names=frame (unresolved_dot_expr type='<null>' field 'bounds' (call_expr type='<null>' (unresolved_dot_expr type='<null>' field 'mainScreen' (unresolved_decl_ref_expr type='<null>' name=UIScreen specialized=no)) (tuple_expr type='<null>')))))) (sequence_expr type='<null>' (unresolved_dot_expr type='<null>' field 'backgroundColor' (force_value_expr type='<null>' (unresolved_dot_expr type='<null>' field 'window' (declref_expr type='<null>' decl=AppDelegate.(file).AppDelegate.func decl.self@AppDelegate.swift:17:10 specialized=yes)))) (assign_expr (**NULL EXPRESSION**) (**NULL EXPRESSION**)) (call_expr type='<null>' (unresolved_dot_expr type='<null>' field 'whiteColor' (unresolved_decl_ref_expr type='<null>' name=UIColor specialized=no)) (tuple_expr type='<null>'))) (call_expr type='<null>' (unresolved_dot_expr type='<null>' field 'makeKeyAndVisible' (force_value_expr type='<null>' (unresolved_dot_expr type='<null>' field 'window' (declref_expr type='<null>' decl=AppDelegate.(file).AppDelegate.func decl.self@AppDelegate.swift:17:10 specialized=yes)))) (tuple_expr type='<null>')) (return_stmt (unresolved_decl_ref_expr type='<null>' name=true specialized=no)))) (func_decl "applicationWillResignActive(_:)" type='<null type>' (body_params (pattern_typed implicit (pattern_named implicit 'self')) (pattern_tuple (pattern_typed (pattern_named 'application') (type_ident (component id='UIApplication' bind=none))))) (brace_stmt)) (func_decl "applicationDidEnterBackground(_:)" type='<null type>' (body_params (pattern_typed implicit (pattern_named implicit 'self')) (pattern_tuple (pattern_typed (pattern_named 'application') (type_ident (component id='UIApplication' bind=none))))) (brace_stmt)) (func_decl "applicationWillEnterForeground(_:)" type='<null type>' (body_params (pattern_typed implicit (pattern_named implicit 'self')) (pattern_tuple (pattern_typed (pattern_named 'application') (type_ident (component id='UIApplication' bind=none))))) (brace_stmt)) (func_decl "applicationDidBecomeActive(_:)" type='<null type>' (body_params (pattern_typed implicit (pattern_named implicit 'self')) (pattern_tuple (pattern_typed (pattern_named 'application') (type_ident (component id='UIApplication' bind=none))))) (brace_stmt)) (func_decl "applicationWillTerminate(_:)" type='<null type>' (body_params (pattern_typed implicit (pattern_named implicit 'self')) (pattern_tuple (pattern_typed (pattern_named 'application') (type_ident (component id='UIApplication' bind=none))))) (brace_stmt))))
另外,我们会注意到另一个比较重要的命令行参数:-repl,我们一起玩玩,看看这个工具能力怎么样。
在命令行执行如下命令:
xcrun swift -repl
我们参考“The Swift Programming Language”写一个Hello World,看看效果:
可以使用:Ctrl + D退出解析器。
这里可以得到:
1、swift既可以被编译执行,也可以被解析执行,是真正的动态语言。
2、大家可以用这个工具来学习语言特性。
就分析到这里,希望对大家有帮助。
对苹果“五仁”编程语言Swift的简单分析,布布扣,bubuko.com
原文地址:http://blog.csdn.net/proteas/article/details/28439601