Disassembling CGWindowContextCreate()?

1

From past few days I am trying to find out the location of CGContextRef on screen and window at Graphics Layer of OS X architecture (mostly in quartz). I think in order to create a window one must pass the location and size of that window where it should appear on display and while creation of window in-turn should call CGWindowContextCreate and thus here we can find who keeps track of cgcontext location and how it does that?

But I have very limited knowledge of disassembling. So I need some help in understanding the following assembly and in identifying its signature.

_CGWindowContextCreate:
    +0  00022b33  55                      pushl       %ebp
    +1  00022b34  89e5                    movl        %esp,%ebp
    +3  00022b36  57                      pushl       %edi
    +4  00022b37  56                      pushl       %esi
    +5  00022b38  53                      pushl       %ebx
    +6  00022b39  83ec1c                  subl        $0x1c,%esp
    +9  00022b3c  e800000000              calll       0x00022b41
   +14  00022b41  5b                      popl        %ebx
   +15  00022b42  8b8babcf7e00            movl        0x007ecfab(%ebx),%ecx
   +21  00022b48  85c9                    testl       %ecx,%ecx
   +23  00022b4a  7518                    jne         0x00022b64
   +25  00022b4c  8d832c010000            leal        0x0000012c(%ebx),%eax
   +31  00022b52  89442404                movl        %eax,0x04(%esp)
   +35  00022b56  8d83ebc47e00            leal        0x007ec4eb(%ebx),%eax
   +41  00022b5c  890424                  movl        %eax,(%esp)
   +44  00022b5f  e812017600              calll       0x00782c76                    _pthread_once
   +49  00022b64  e850010000              calll       _CGContextCreate
   +54  00022b69  89c7                    movl        %eax,%edi
   +56  00022b6b  85c0                    testl       %eax,%eax
   +58  00022b6d  751d                    jne         0x00022b8c
   +60  00022b6f  8d833d977800            leal        0x0078973d(%ebx),%eax
   +66  00022b75  89442404                movl        %eax,0x04(%esp)
   +70  00022b79  8d83fb957800            leal        0x007895fb(%ebx),%eax
   +76  00022b7f  890424                  movl        %eax,(%esp)
   +79  00022b82  e8a8dc1500              calll       _CGPostError
   +84  00022b87  e9d7000000              jmp         0x00022c63
   +89  00022b8c  c74424040c000000        movl        $0x0000000c,0x04(%esp)
   +97  00022b94  c7042401000000          movl        $0x00000001,(%esp)
  +104  00022b9b  e840fd7500              calll       0x007828e0                    _calloc
  +109  00022ba0  89c2                    movl        %eax,%edx
  +111  00022ba2  85c0                    testl       %eax,%eax
  +113  00022ba4  750a                    jne         0x00022bb0
  +115  00022ba6  893c24                  movl        %edi,(%esp)
  +118  00022ba9  e8e7150400              calll       _CGContextRelease
  +123  00022bae  eb5b                    jmp         0x00022c0b
  +125  00022bb0  8b4508                  movl        0x08(%ebp),%eax
  +128  00022bb3  8902                    movl        %eax,(%edx)
  +130  00022bb5  8b450c                  movl        0x0c(%ebp),%eax
  +133  00022bb8  894204                  movl        %eax,0x04(%edx)
  +136  00022bbb  c7420800000000          movl        $0x00000000,0x08(%edx)
  +143  00022bc2  895714                  movl        %edx,0x14(%edi)
  +146  00022bc5  8d8391350700            leal        0x00073591(%ebx),%eax
  +152  00022bcb  89471c                  movl        %eax,0x1c(%edi)
  +155  00022bce  c7471003000000          movl        $0x00000003,0x10(%edi)
  +162  00022bd5  8b4510                  movl        0x10(%ebp),%eax
  +165  00022bd8  89442404                movl        %eax,0x04(%esp)
  +169  00022bdc  891424                  movl        %edx,(%esp)
  +172  00022bdf  ff93abcf7e00            call        *0x007ecfab(%ebx)
  +178  00022be5  89c6                    movl        %eax,%esi
  +180  00022be7  85c0                    testl       %eax,%eax
  +182  00022be9  7524                    jne         0x00022c0f
  +184  00022beb  893c24                  movl        %edi,(%esp)
  +187  00022bee  e8a2150400              calll       _CGContextRelease
  +192  00022bf3  8d833d977800            leal        0x0078973d(%ebx),%eax
  +198  00022bf9  89442404                movl        %eax,0x04(%esp)
  +202  00022bfd  8d8323967800            leal        0x00789623(%ebx),%eax
  +208  00022c03  890424                  movl        %eax,(%esp)
  +211  00022c06  e824dc1500              calll       _CGPostError
  +216  00022c0b  31ff                    xorl        %edi,%edi
  +218  00022c0d  eb54                    jmp         0x00022c63
  +220  00022c0f  89442404                movl        %eax,0x04(%esp)
  +224  00022c13  893c24                  movl        %edi,(%esp)
  +227  00022c16  e839180000              calll       _CGContextSetDelegate
  +232  00022c1b  893424                  movl        %esi,(%esp)
  +235  00022c1e  e8bd180000              calll       _CGContextDelegateRelease
  +240  00022c23  8b5510                  movl        0x10(%ebp),%edx
  +243  00022c26  85d2                    testl       %edx,%edx
  +245  00022c28  7431                    je          0x00022c5b
  +247  00022c2a  8b8307d57c00            movl        0x007cd507(%ebx),%eax
  +253  00022c30  8b00                    movl        (%eax),%eax
  +255  00022c32  89442404                movl        %eax,0x04(%esp)
  +259  00022c36  8b4510                  movl        0x10(%ebp),%eax
  +262  00022c39  890424                  movl        %eax,(%esp)
  +265  00022c3c  e87ff57500              calll       0x007821c0                    _CFDictionaryGetValue
  +270  00022c41  85c0                    testl       %eax,%eax
  +272  00022c43  7416                    je          0x00022c5b
  +274  00022c45  c744240800000000        movl        $0x00000000,0x08(%esp)
  +282  00022c4d  89442404                movl        %eax,0x04(%esp)
  +286  00022c51  893c24                  movl        %edi,(%esp)
  +289  00022c54  e8d9dd1500              calll       _CGContextAddFilter
  +294  00022c59  89c7                    movl        %eax,%edi
  +296  00022c5b  893c24                  movl        %edi,(%esp)
  +299  00022c5e  e88f180000              calll       _CGContextRegistryAddContext
  +304  00022c63  89f8                    movl        %edi,%eax
  +306  00022c65  83c41c                  addl        $0x1c,%esp
  +309  00022c68  5b                      popl        %ebx
  +310  00022c69  5e                      popl        %esi
  +311  00022c6a  5f                      popl        %edi
  +312  00022c6b  c9                      leave
  +313  00022c6c  c3                      ret

Thank you for your time and help.

macos
core-graphics
reverse-engineering
quartz-graphics
asked on Stack Overflow Jun 30, 2011 by RLT

1 Answer

0

CGContextRef CGWindowContextCreate(int, int, void*);

answered on Stack Overflow Jul 6, 2011 by RLT

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