[Benoist3012]

I've been unable to find any good answer to this question, so I'm posting here, can someone show me a good example to call function with its signature. Thanks in advance.

[asherkin]

What function do you want to call? The process is different between static and member functions.

[Benoist3012]

Oh? Well I want to call the constructor "Path::Path" which a member function if I'm right. I believe an example for both would be appreciated.

[Potato Uno]

I too would like to know how to use a signature to call a function from an extension.

Preferably not by firing a forward to pawn to a plugin and have it do an SDKCall from there.

[Dr!fter]

A good way to learn is to look at some of the extensions from sourcemod. The cstrike and tf2 extension both make function calls using signatures and I believe some even using offsets (not 100% sure). I know for a fact the cstrike one handles both member calls and non member calls, although following some of the code is weird since in csgo the windows binary is ltcg'd which results in asm being required sometimes.

Ill try to quickly break one down.
https://github.com/alliedmodders/sou...tives.cpp#L339

First we need to create a wrapper for the call.

PHP Code:

static ICallWrapper *pWrapper = NULL;

    if (!pWrapper)
    {
        REGISTER_NATIVE_ADDR("TerminateRound",
            PassInfo pass[2]; \
            pass[0].flags = PASSFLAG_BYVAL; \
            pass[0].type = PassType_Basic; \
            pass[0].size = sizeof(float); \
            pass[1].flags = PASSFLAG_BYVAL; \
            pass[1].type = PassType_Basic; \
            pass[1].size = sizeof(int); \
            pWrapper = g_pBinTools->CreateCall(addr, CallConv_ThisCall, NULL, pass, 2))
    } 


As can be seen it is a member call with 2 params a float and an int. The NULL represents the return you would create a similar PassInfo if you had a return (there is an example in the same file i linked).

PHP Code:

unsigned char vstk[sizeof(void *) + sizeof(float)+ sizeof(int)];
    unsigned char *vptr = vstk;

    *(void **)vptr = gamerules;
    vptr += sizeof(void *);
    *(float *)vptr = sp_ctof(params[1]);
    vptr += sizeof(float);
    *(int*)vptr = reason;

    pWrapper->Execute(vstk, NULL); 


Next is creating the stack for the function call and then assign it to the ptr. The size of the stack is |this| ptr (for member calls) + the size of all the arguments. First thing onto the stack is |this| then move forward the size of the pointer add the first param move forward again and add the second param. Then execute the call. The NULL in this case is the return pointer used if there is a return.

Hope that explains it.... sort of. It was a rather quick explanation.