call_function_raw(), BinaryBuffer functions, dlopen/dlsym/dlclose

[kung foo man]

Ok, a "nicer" call_function, done with CoDScript only:

		call_function(function, signature, a, b, c, d, e, f, g, h, i, j, k, l) {
    args = [];
    args[args.size] = a;
    args[args.size] = b;
    args[args.size] = c;
    args[args.size] = d;
    args[args.size] = e;
    args[args.size] = f;
    args[args.size] = g;
    args[args.size] = h;
    args[args.size] = i;
    args[args.size] = j;
    args[args.size] = k;
    args[args.size] = l;
    
    buf = memory_malloc(128);
    bb = binarybuffer_new(buf);
    
    signatureClean = ""; // without the . (varargs-marker)
    for (ii=0; ii<signature.size; ii++)
        if (signature[ii] != ".")
            signatureClean += signature[ii];
    
    signature_pos = 0;
    for (ii=0; ii<args.size; ii++) {
        //printf("ii=% type=%\n", ii, getType(args[ii]));

        needGuessType = ii >= signatureClean.size;
        //printf("ii=%, sigClean.size=% needGuessType=%\n", ii, signatureClean.size, needGuessType);
        if ( ! needGuessType) {
            // don't guess type when it's given in signature
            binarybuffer_write(bb, signatureClean[ii], args[ii]);
            continue;
        }
        
        type = "";
        switch (getType(args[ii])) {
            case "INT":    type = "i"; break;
            case "STRING": type = "s"; break;
            case "FLOAT":  type = "f"; break;
        }
        signature += type; // only add missing types to signature
        binarybuffer_write(bb, type, args[ii]); // add data with our guessed type
    }

    //printf("Function: % Signature: %\n", function, signature);
    ret = call_function_raw(function, signature, buf);
    
    memory_free(buf);
    binarybuffer_free(bb);
    
    return ret;
} 
	

Call like:

		    call_function(libc_printf, "s.", "hi!!! int=%d float=%f string=%s\n", 123, 0.345, "yo"); 
	

Output (with debug messages):

ii=0 type=STRING
ii=1 type=INT
ii=2 type=FLOAT
ii=3 type=STRING
ii=4 type=UNDEFINED
ii=5 type=UNDEFINED
ii=6 type=UNDEFINED
ii=7 type=UNDEFINED
ii=8 type=UNDEFINED
ii=9 type=UNDEFINED
ii=10 type=UNDEFINED
ii=11 type=UNDEFINED
Function: -146088352 Signature: s.ifs
hi!!! int=123 float=0.345000 string=yo

Now we only need to declare the "needed" signature "s.", for printf(char *msg, ...), because we can figure out the rest dynamically, based on getType(args[ii]).

Limitation:

We can't use %c (1 byte char) or %g (8 bytes double) without explicit signature, because these types don't exist in CoDScript itself, so there is no way to tell binarybuffer_write() about the type-information only with getType().

For that case, you need to make the signature explicit:

		call_function(libc_printf, "s.ifsdc", "hi!!! int=%d float=%f string=%s double=%g char=%c\n", 123, 0.345, "yo", 0.123, "#"); 
	

Output:

hi!!! int=123 float=0.345000 string=yo double=0.123 char=#

Return values:

Just added this in new commit: https://github.com/kungfooman/libcod...dff68c1ba77ba7
Binaries are updated: http://killtube.org/downloads/libcod/2015.01.17/

		    ret = call_function(libc_printf, "s.", "asd\n");
    printf("printed chars: %\n", ret); 
	

Output:

asd
printed chars: 4

Basically that's just eax as int though atm. Some converting based on signature would be nice, like "s.)i" for "return an int".