AlliedModders - Accesing metamod modules by cvar address

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Accesing metamod modules by cvar address

I was trying to hook functions in metamod modules using an amxmodx module and I found that, in linux using dladdr within the cvar pointer registered by the metamod module (even with amxmodx) can't be mapped to an already opened library.

For example

Code:

cvar_t *a = CVAR_GET_POINTER("amx_client_languages");



Dl_info info;

dladdr((void *)a, &info)

Here dladdr returns 0, so it can't find the associated library for that memory address.

Using GDB I found the address is in non-allocated space by any library loaded...
It's really strange. At least should be engine_i686.so.

If I do the same with mp_timelimit or sv_proxies I get the corresponding library (CS or ENGINE).

Some time ago I was trying to do this with orpheu using the included method to define additional libraries and I get the same error.

It's possible that last updates on engine changed something about how cvar pointers works?

Anyone has similar problems?

Re: Accesing metamod modules by cvar address

Metamod does not supply plugin configurable variables directly to the engine to avoid segmentation
faults. Check the 'reg_support.cpp' at line 178, it should explain everything for you.

Re: Accesing metamod modules by cvar address

Yes, I found that the correct way is to hook CVarRegister before OnMetaAttach, then at each call check cvar_t pointer passed as parameter and that memory will be for the calling module.

Thanks