dyld加载过程

iOS的app启动过程

• iOS的app启动过程
  • 概述
    • 
  • 详细
    • 
• iOS的app启动的不同阶段
  • Pre-main阶段
    • 
  • main阶段
    • 
• iOS的app启动调用函数
  • 

dyld加载过程

• dyld2 vs dyld3
  • 
• dyld加载过程
  • 图
    • 
  • 文字版
    • 图
      • 

dyld加载过程1

(lldb) bt
* thread #1, queue = 'com.apple.main-thread', stop reason = breakpoint 23.2
  * frame #0: 0x000000018d124174 libdyld.dylib`dladdr
    frame #1: 0x000000010b0bfbac AwemeCore`___lldb_unnamed_symbol13025$$AwemeCore + 80
    frame #2: 0x000000018d041c38 libobjc.A.dylib`CALLING_SOME_+initialize_METHOD + 20
    frame #3: 0x000000018d04742c libobjc.A.dylib`initializeNonMetaClass + 644
    frame #4: 0x000000018d0471f8 libobjc.A.dylib`initializeNonMetaClass + 80
    frame #5: 0x000000018d047ba8 libobjc.A.dylib`initializeAndMaybeRelock(objc_class*, objc_object*, mutex_tt<false>&, bool) + 284
    frame #6: 0x000000018d05450c libobjc.A.dylib`lookUpImpOrForward + 700
    frame #7: 0x000000018d0448a8 libobjc.A.dylib`object_setClass + 104
    frame #8: 0x000000018d29da70 CoreFoundation`_CFRuntimeCreateInstance + 580
    frame #9: 0x000000018d2bcb74 CoreFoundation`__CFStringCreateImmutableFunnel3 + 1944
    frame #10: 0x000000018d2bcef8 CoreFoundation`CFStringCreateWithCString + 92
    frame #11: 0x000000018d29f610 CoreFoundation`__CFInitialize + 812
    frame #12: 0x0000000104fddfac dyld`ImageLoaderMachO::doImageInit(ImageLoader::LinkContext const&) + 248
    frame #13: 0x0000000104fde580 dyld`ImageLoaderMachO::doInitialization(ImageLoader::LinkContext const&) + 40
    frame #14: 0x0000000104fd95d0 dyld`ImageLoader::recursiveInitialization(ImageLoader::LinkContext const&, unsigned int, char const*, ImageLoader::InitializerTimingList&, ImageLoader::UninitedUpwards&) + 548
    frame #15: 0x0000000104fd953c dyld`ImageLoader::recursiveInitialization(ImageLoader::LinkContext const&, unsigned int, char const*, ImageLoader::InitializerTimingList&, ImageLoader::UninitedUpwards&) + 400
    frame #16: 0x0000000104fd8334 dyld`ImageLoader::processInitializers(ImageLoader::LinkContext const&, unsigned int, ImageLoader::InitializerTimingList&, ImageLoader::UninitedUpwards&) + 184
    frame #17: 0x0000000104fd83fc dyld`ImageLoader::runInitializers(ImageLoader::LinkContext const&, ImageLoader::InitializerTimingList&) + 92
    frame #18: 0x0000000104fca3d0 dyld`dyld::initializeMainExecutable() + 136
    frame #19: 0x0000000104fcedb4 dyld`dyld::_main(macho_header const*, unsigned long, int, char const**, char const**, char const**, unsigned long*) + 4616
    frame #20: 0x0000000104fc9208 dyld`dyldbootstrap::start(dyld3::MachOLoaded const*, int, char const**, dyld3::MachOLoaded const*, unsigned long*) + 396
    frame #21: 0x0000000104fc9038 dyld`_dyld_start + 56

==

• dyld`_dyld_start
  • dyld`dyldbootstrap::start
    • dyld`dyld::_main
      • dyld`dyld::initializeMainExecutable
        • dyld`ImageLoader::runInitializers
          • dyld`ImageLoader::processInitializers
            • dyld`ImageLoader::recursiveInitialization
              • dyld`ImageLoaderMachO::doInitialization
                • dyld`ImageLoaderMachO::doImageInit
                  • ...
                    • libdyld.dylib`dladdr

dyld加载过程2

• _dyld_start
  • dyldbootstrap: : start
    • dyld: : _main
      • dyld: : initializeMainExecutable
        • ImageLoader::runInitializers
          • ImageLoader::processInitializers
            • ImageLoader::recursiveInitialization
              • Dyld ::notifySingle
                • libobjC.a. dylib load_images
                  • +[ViewController load]

dyld加载过程3

(lldb) bt
* thread #1, queue = 'com.apple.main-thread', stop reason = breakpoint 6.1
  * frame #0: 0x0000000102495310 libAwemeDylib.dylib`_logos_method$_ungrouped$NSString$stringByAppendingString$(self="https://", _cmd="stringByAppendingString:", aString=0x0000000000000000) at AwemeDylib.xm:175:29
    frame #1: 0x0000000108532cf8 AwemeCore`___lldb_unnamed_symbol3548$$AwemeCore + 520
...
    frame #38: 0x00000001c2ecf60c FrontBoardServices`-[FBSSerialQueue _performNextFromRunLoopSource] + 28
    frame #39: 0x00000001bdcd0a00 CoreFoundation`__CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ + 24
    frame #40: 0x00000001bdcd0958 CoreFoundation`__CFRunLoopDoSource0 + 80
    frame #41: 0x00000001bdcd00f0 CoreFoundation`__CFRunLoopDoSources0 + 180
    frame #42: 0x00000001bdccb23c CoreFoundation`__CFRunLoopRun + 1080
    frame #43: 0x00000001bdccaadc CoreFoundation`CFRunLoopRunSpecific + 464
    frame #44: 0x00000001c7c6b328 GraphicsServices`GSEventRunModal + 104
    frame #45: 0x00000001c1dd863c UIKitCore`UIApplicationMain + 1936
    frame #46: 0x000000010efec094 AwemeCore`awemeMain + 200
    frame #47: 0x0000000102267ca4 Aweme`___lldb_unnamed_symbol21$$Aweme + 12
    frame #48: 0x00000001bdb54360 libdyld.dylib`start + 4

• libdyld.dylib`start 开始的调用顺序
  • app相关逻辑：Aweme___lldb_unnamed_symbol21$$Aweme、AwemeCoreawemeMain
    • 然后才是其他系统常见函数
      • UIKitCore`UIApplicationMain
        • ...