How does JetBrains AppCode launch the iOS Simulator?

Plumenator picture Plumenator · May 30, 2011 · Viewed 8.9k times · Source

I just looked at JetBrains's App Code IDE and it seems to be able to launch the iOS Simulator and run applications in it.

When I had to automate the deployment of my projects I had to resort to Applescript and GUI automation.

They seem to be using a closed tool called 'simlauncher'. I wonder what the magic behind it could be.

Update:

  1. On looking at Activity Monitor, I see that osascript gets launched from simlauncher before the simulator is launched. Could it be Applescript again? I thought iOS Simulator.app was not scriptable.
  2. iOS Simulator seems to be launched by launchd, so simlauncher is definitely not launching it by itself. Also, simlauncher stays only until the actual application is running in the simulator. They're polling for it perhaps?
  3. For device builds, they're using AMDeviceService, which is probably a version of Apple Mobile Device Service. Is this a technique from the jail broken SDK?

A little more info on the simulator from the output of 'ps':

plumenator 26404  12.9  1.3   290172  52772   ??  SX    8:56PM   0:03.62 /Users/plumenator/Library/Application Support/iPhone Simulator/4.3.2/Applications/817A280D-1F74-4755-B848-B04EC8A24ADA/xxx.app/xxx
plumenator 26395   2.3  0.3   444208  13560   ??  S     8:56PM   0:00.72 /Developer/Platforms/iPhoneSimulator.platform/Developer/Applications/iPhone Simulator.app/Contents/MacOS/iPhone Simulator -SessionOnLaunch NO
plumenator 26402   1.4  0.8   318320  33052   ??  Us    8:56PM   0:00.86 /Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator4.3.sdk/System/Library/CoreServices/SpringBoard.app/SpringBoard -SBDisableAutoDim YES -SBAutoLockTime -1 -SBAutoDimTime -1 -SBDontLockAfterCrash YES -SBDidShowReorderText YES -SBFakeBars YES -SBDontAnimateAppleDown YES -SBEnableDoubleHeightToggling YES
plumenator 26406   0.0  0.4  2466496  15792   ??  Ss    8:56PM   0:00.16 /Developer/Platforms/iPhoneSimulator.platform/Developer/usr/libexec/gdb/gdb-i386-apple-darwin --arch i386 --interp=mi1 -q
plumenator 26401   0.0  0.1   106584   5688   ??  S     8:56PM   0:00.30 /Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator4.3.sdk/usr/libexec/lsd
plumenator 26400   0.0  0.1   105228   4204   ??  S     8:56PM   0:00.13 /Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator4.3.sdk/usr/libexec/installd -t 30
plumenator 26399   0.0  0.3   223488  11464   ??  Ss    8:56PM   0:00.15 /Developer/Platforms/iPhoneSimulator.platform/Developer/Applications/iPhone Simulator.app/Contents/MacOS/SimulatorBridge 26395

Now I suppose it's just a matter of sorting the commands according to the pid and executing them. :-)

There's a problem, though. All these binaries refer to dylibs present in the simulator platform's root. When I run them directly, they look for those in '/'.

Is there a way to set the path for dylibs before running a command? This looks promising: http://sacredsoftware.net/svn/misc/StemLibProjects/eaglshell/tags/2.1.0/Makefile

https://github.com/BlueFrogGaming/icuke has good info too.

Answer

Vincent Guerci picture Vincent Guerci · Jun 10, 2011

AppCode use a special wrapper to do this, that you noticed in its console :

/Applications/AppCode-108.379.app/bin/simlauncher 4.3 debug iphone <PATH_TO_APP> <STDOUT> <STDERR>

simlauncher is a non documented / not friendly mach-o binary... But here is a quick analysis of it:

  • To launch simulator it uses a private Apple framework (otool -L simlauncher) :

    /Applications/AppCode-108.379.app/bin/simlauncher:
    @rpath/iPhoneSimulatorRemoteClient.framework/Versions/A/iPhoneSimulatorRemoteClient (compatibility version 1.0.0, current version 12.0.0)
    
  • This framework is bundled with Xcode:

    <XCODE_PATH>/Platforms/iPhoneSimulator.platform/Developer/Library/PrivateFrameworks/iPhoneSimulatorRemoteClient.framework
    
  • And is used like that (class-dump simlauncher) (DTiPhoneSimulator* are from Apple Framework):

    @protocol DTiPhoneSimulatorSessionDelegate
    - (void)session:(id)arg1 didEndWithError:(id)arg2;
    - (void)session:(id)arg1 didStart:(BOOL)arg2 withError:(id)arg3;
    @end
    
    @interface Launcher : NSObject <DTiPhoneSimulatorSessionDelegate> {
        DTiPhoneSimulatorSession *mySession;
    }
    
    - (int)launch:(id)arg1 sdkVersion:(id)arg2 wait:(BOOL)arg3 device:(int)arg4 sout:(id)arg5 eout:(id)arg6 argument:(id)arg7 env:(id)arg8;
    - (void)session:(id)arg1 didEndWithError:(id)arg2;
    - (void)session:(id)arg1 didStart:(BOOL)arg2 withError:(id)arg3;
    
    @end
    

About the other binary AMDeviceService I just can say it uses ProtocolBuffers in order I guess to communicate with MobileDevice service... Once again, undocumented stuff...

Quick conclusion, sorry, there is no easy way to launch iPhoneSimulator using the JetBrains way, unless reversing Apple privates/not documented APIs... like Jetbrains folks did, I love their tools, they are top guns, can't wait appcode to be gold, already working on it everyday :)

EDIT: See answer below from a JetBrains employee... @JetBrains, would be great to have some sort of AMDeviceService documented to automate some stuff... ;)