r3wp [groups: 83 posts: 189283]
  • Home
  • Script library
  • AltME Archive
  • Mailing list
  • Articles Index
  • Site search
 

World: r3wp

[!REBOL3 Extensions] REBOL 3 Extensions discussions

Maxim
9-Nov-2010
[1675]
ah yes... they are allocated on the stack, so memory its not cleared 
by default.
Andreas
9-Nov-2010
[1676]
Updated the snippet accordingly:
https://gist.github.com/0c6305d7c25e40742b31
Maxim
9-Nov-2010
[1677x3]
actually, in Olde's code its:   

 s.index = 0;
actually... its:    arg.index = 0;
we could propose a usefull macro to not get bitten by  this  again:

something like:

#define NEW_RXIARG(v) RXIARG v; v.index=0
Andreas
9-Nov-2010
[1680x2]
CLEARS(&a);
RXIARG a;
CLEARS(&a);

is the most sensible way. but then you'll better #include <string.h> 
(at least until some include woes in the hostkit headers are straightened 
out).
Maxim
9-Nov-2010
[1682]
however we do it, the problem is not in how, but that we forget to 
do it in the first place.
Andreas
9-Nov-2010
[1683]
that's C for you :)
Maxim
9-Nov-2010
[1684]
which is why a standard macro which takes care of that would be nice... 
in the same idea than the RL_MAKE_BLOCK (which I know isn't exactly 
the same since its just a wrapper around the RL vector)
Andreas
9-Nov-2010
[1685]
you have to make sure to initialise all stack- and heap-allocated 
memory
Maxim
9-Nov-2010
[1686]
yep.
Oldes
10-Nov-2010
[1687x2]
Ah.. thanks.. so I made another small step in learning extensions:) 
Thanks. I'm sure I will have more questions later. But I must work 
now for a while.
When I have command like:
	test: command [str [string!]]
And on C side I need a pointer to this string, how to get it?
Maxim
10-Nov-2010
[1689]
str_arg = RXA_SERIES(frm, 1);
Oldes
10-Nov-2010
[1690]
with:
 char *str_arg;
?
Maxim
10-Nov-2010
[1691]
sorry..

REBSER * str_arg = RXA_SERIES(frm, 1);
Oldes
10-Nov-2010
[1692x2]
That's not working, the function I'm trying to call is:

char **MagickQueryConfigureOptions(const char *pattern, unsigned 
long *number_options)
And I would like to use REBOL input for the *pattern.
Does it mean that I must use FOR loop with RL_GET_CHAR or I can get 
the pointer directly?
Maxim
10-Nov-2010
[1694x3]
loop with RL_GET_CHAR
to get the length of the REBOL string you need to use this:
RL_Series(str_arg, RXI_SER_TAIL)
Oldes
10-Nov-2010
[1697x2]
with RL_Series I have this error:  undefined reference to `_imp__RL_Series'
This works:
            REBSER *ser;
            i32 len;
            
            ser = RXA_SERIES(frm, 1);

            len = RL_SERIES (ser, RXI_SER_TAIL) - RXA_INDEX(frm, 1);

            char pattern[len]; 
            for(n = 0; n < len; ++n)   
                pattern[n] = RL_GET_CHAR(ser, n);
Maxim
10-Nov-2010
[1699]
yeah... sorry... I have my own defines, which include the required 
files.
Oldes
10-Nov-2010
[1700]
What I must include to be able use RL_Print?
Maxim
10-Nov-2010
[1701]
AFAIK, you should just need 

#include "reb-host.h"
Oldes
10-Nov-2010
[1702x2]
That I have, but I get the similar error: undefined reference to 
`_imp__RL_Print'
It would be much more easier to play with extensions with the ability 
to trace it.
Maxim
10-Nov-2010
[1704]
is your file a .c or .cpp  ?
Oldes
10-Nov-2010
[1705]
.c
Maxim
10-Nov-2010
[1706]
you can try adding 

extern  void RL_Print(char *fmt, ...);

at the begining of your file.
Oldes
10-Nov-2010
[1707]
That does not works.
Maxim
10-Nov-2010
[1708x2]
are you using gcc of VS ?
of = or
Oldes
10-Nov-2010
[1710x3]
GCC
it's not working with Andreas' minimal example as well - http://www.curecode.org/rebol3/ticket.rsp?id=1727
(wrong link, this one https://gist.github.com/0c6305d7c25e40742b31
)
Maxim
10-Nov-2010
[1713x2]
ah, I did a little bit of searching and I think I understand... 

try using RL_PRINT() instead.
its strange that I've never had a problem with this though cause 
I use RL_Print in all my files, but I realize that it might just 
be luck, that in my setup I don't have the linking problem you are 
having.
Oldes
10-Nov-2010
[1715]
That works, but only with 2 args.
Maxim
10-Nov-2010
[1716x5]
RL_PRINT should work in any uses of the host_kit
ok... that is easy to fix.
open reb-lib.h
and replace:
#define RL_PRINT(a,b)               RL->print(a,b)

with:
#define RL_PRINT(a,b)               RL->print(a,__VA_ARGS__)

can't test it right now, but that should work.
the function itself is defined with variable arguments, its just 
the #define which isn't ... the above redefines it so it matches 
the function declaration.
Oldes
10-Nov-2010
[1721]
__VA_ARGS__ can only appear in the expansion of a C99 variadic macro
Never mind... I really have to do real work now :)
Maxim
10-Nov-2010
[1722]
what?  I'm using it my own gcc compiled version of the host-kit... 
I don't understand... Andreas will have to step in... I don't know 
why you're having that error.
Oldes
10-Nov-2010
[1723]
Actually it's:

../src/include/reb-lib.h:270:49: warning: __VA_ARGS__ can only appear 
in the expansion of a C99 variadic macro

wand.c:74:43: macro "RL_PRINT" passed 3 arguments, but takes just 
2
wand.c: In function `RX_Call':

wand.c:74: error: `RL_PRINT' undeclared (first use in this function)
Maxim
10-Nov-2010
[1724]
ok, well, I guess you'll have to use just two args for now  ;-)