• Les Baker (36/36) Aug 14 2003 I am working on porting some Win32 dialog-box generation code I wrote in
• Mike Wynn (56/75) Aug 14 2003 ubyte[] (as you found out below) is a length and pointer to start of "sl...

"Les Baker" <lesbaker innovaREMOVETHIS.net> writes:

I am working on porting some Win32 dialog-box generation code I wrote in
C++, which uses an in-memory dialog template and DialogBoxIndirectParam() to
build a dialog box "on-the-fly". It uses the DLGTEMPLATE and DLGITEMTEMPLATE
structures, which are not terribly complex. I am trying to get them into a
ubyte[] array for use with the OutBuffer phobos class, which will eventually
go to . Unfortunately, the following doesn't seem to work well.

static DLGITEMTEMPLATE dlgButton =
{
    style : WS_CHILD | WS_VISIBLE | BS_DEFPUSHBUTTON,
    dwExtendedStyle : 0,
    x : 150,
    y : 5,
    cx : 50,
    cy : 14,
    id : IDOK
};

// a bit later in the code...
ubyte[] dlgTemplateBuf = cast(ubyte[]) (cast(ubyte *) (&dlgTemplate))[0 ..
dlgTemplate.size];
// so that I can do this
outbuf.write( dlgTemplateBuf );

Yes, it looks messy; I'm probably doing something extremely stupid, so
consider this a "D newbie question" =). I thought I could just cast to
ubyte[], but that didn't work. Has anyone else used OutBuffer with UDT's?

On a side note:

The most frustrating thing was that when I first started porting the code, I
wanted to use an inline struct definition for the *entire* Win32 dialog box
template and the dialog items, which have some embedded Unicode
null-terminated strings. So I put some wchar[] dynamic arrays in the struct
definition. It turns out that a pointer/length pair is being stored instead
of the actual Unicode chars, and that's not what Windows likes to "see" when
it is reading the dialog template. I really wish there was a property of
UDT's that would persist it as a flat array of bytes at that point in the
code. (That could be done on the user side if introspection were in D, but
even then, introspection wouldn't benefit non-class UDT's).

Les Baker

"Mike Wynn" <mike.wynn l8night.co.uk> writes:

"Les Baker" <lesbaker innovaREMOVETHIS.net> wrote in message
news:bhgk6u$ip8$1 digitaldaemon.com...
 // a bit later in the code...
 ubyte[] dlgTemplateBuf = cast(ubyte[]) (cast(ubyte *) (&dlgTemplate))[0 ..
 dlgTemplate.size];
 // so that I can do this
 outbuf.write( dlgTemplateBuf );

 Yes, it looks messy; I'm probably doing something extremely stupid, so
 consider this a "D newbie question" =). I thought I could just cast to
 ubyte[], but that didn't work. Has anyone else used OutBuffer with UDT's?

ubyte[] (as you found out below) is a length and pointer to start of "slice"
you should only need to do
ubyte[] sliceme( ubyte * ptr, int start, int finish ) {
    ubyte[] buf = ptr[start..finish];
//    is buf.addr = ptr + start; buf.len = finish - start;
    return buf;
}


 On a side note:

 The most frustrating thing was that when I first started porting the code,

I
 wanted to use an inline struct definition for the *entire* Win32 dialog

box
 template and the dialog items, which have some embedded Unicode
 null-terminated strings. So I put some wchar[] dynamic arrays in the

struct
 definition. It turns out that a pointer/length pair is being stored

instead
 of the actual Unicode chars, and that's not what Windows likes to "see"

when
 it is reading the dialog template. I really wish there was a property of
 UDT's that would persist it as a flat array of bytes at that point in the
 code. (That could be done on the user side if introspection were in D, but
 even then, introspection wouldn't benefit non-class UDT's).

you can (ish) with templates ....

template array( int size ) {
    struct myholder {
        byte[size] buf;
    }
}

instance array(8) block_of_eight;
block_of_eight.myholder foo;

foo.buf is byte[8]  not byte[] with len of 8
however as the length is know you can pass it as a byte[]


import c.stdio;

ubyte[] make_raw( void * ptr, int len ) {
 return (cast(ubyte*)ptr)[0..len];
}

template mystructs( int size ) {
 struct myElement {
  int a;
 }
 struct myholder {
  int length;
  myElement[size] buf;
 }
 ubyte[] makeStruct( int[] elements ) {
  if ( elements.length != size ) { throw new Exception( "invalid arg
length" ); }
  myholder * h = new myholder();
  h.length = size;
  for( int i = 0; i < size; i++ ) {
   h.buf[i].a = elements[i];
  }
  return make_raw( h, myholder.size );
    }
}



int main( char[][] args ) {
 static int[] ar = [1,2,3];
 ubyte[] raw = instance mystructs(3).makeStruct( ar );

 printf( "raw.length:%d\n", raw.length );
 for( int i =0; i < raw.length; i++ ) {
  printf( "%02x ", raw[i] );
 }

 return 0;
}