Accessing the symbol table of a mach-o file

[Jacob Carlborg]

On 3/3/10 18:54, KennyTM~ wrote:
> On Mar 4, 10 00:02, Jacob Carlborg wrote:
>> I posted this message in the learn newsgroup without any response, I'm
>> now hoping to have better response here.
>>
>> I'm trying to access the symbol table of a mach-o file. I've managed to
>> access the symbol table but I have two problems:
>>
>> 1. It seems I can't access the whole symbol table if I compare my output
>> to the output of nm. For example, I have a global struct in the file I'm
>> examining which doesn't show up in my output. I have a global class that
>> does show up but not the methods in the class.
>>
>> 2. When I'm printing the string representation (accessed from the string
>> table) of some of the symbols they don't seem to be complete. For
>> example "inte" instead of "internal". Then the next symbol I print is
>> the rest of the previous symbol.
>>
>> This is the code I have so far, in some kind of pseudo code format:
>>
>> header = the header of the mach-o file
>> cmd = cast(load_command*) (cast(byte*) header + size of header)
>>
>> loop (number of load commands)
>> {
>> cmd = cast(type of command) (cast(byte*) cmd + size of command)
>>
>> if (cmd == symbol table command)
>> break
>> }
>>
>> symbolTable = cast(nlist*) (cast(byte*) header + symbol table offset)
>> stringTable = cast(char*) (cast(byte*) header + string table offset)
>>
>> foreach (entry in symbolTable)
>> {
>> symbol = stringTable + string table index
>> print symbol
>> }
>>
>> Does anyone have any idea what I can do about the above two problems?
>
> If the Mach-O file is from Mac OS X 10.6 or iPhone OS 3.1, your method
> won't work because the symbol table format is changed. See
> http://developer.apple.com/mac/library/releasenotes/DeveloperTools/RN-dyld/index.html.

No, it's compiled and run on Mac OS X 10.5.7.