From: Cooper Stevenson <cooper@...>
Date: 2006-08-07T02:30:11+09:00
Subject: Ruby Newbie: Simple C Wrappers?

Hello,

My apologies if this has already been discussed in detail on the list 
but I've been working with the Pragmatics an O'Rielly's for some time 
now and I think it's time to call for a 'help.'

I would like to interface what seems to be a straightforward main 
program (as I understand it that's all I need to interface, not the rest 
of the .c files, please correct me if this is in error) and have 
achieved a compile with an empty Init function like so:

    void
    Init_jzipr()
    {

    }

irb works:

   $ irb
   irb(main):001:0> require 'jzipr'
   => true

I am finding the next step--creating the class--difficult. Here's 
jzip.c--it's doesn't look like much but doing it for the first time...


------------------Begin jzip.c------------------------

/* $Id: jzip.c,v 1.3 2000/10/04 23:07:57 jholder Exp $
  * --------------------------------------------------------------------
  * see doc/License.txt for License Information
  * --------------------------------------------------------------------
  *
  * File name: $Id: jzip.c,v 1.3 2000/10/04 23:07:57 jholder Exp $
  *
  * Description:
  *
  * Modification history:
  * $Log: jzip.c,v $
  * Revision 1.3  2000/10/04 23:07:57  jholder
  * fixed redirect problem with isolatin1 range chars
  *
  * Revision 1.2  2000/05/25 22:28:56  jholder
  * changes routine names to reflect zmachine opcode names per spec 1.0
  *
  * Revision 1.1.1.1  2000/05/10 14:21:34  jholder
  *
  * imported
  *
  *
  * --------------------------------------------------------------------
  */

/*
  * jzip.c
  *
  * Z code interpreter main routine.
  *
  * Revisions list:
  * Mark Howell 10-Mar-1993 V2.0    howell_ma@movies.enet.dec.com
  *                         V2.0.1(some of a-f)
  * John Holder 22-Nov-1995 V2.0.1g j-holder@home.com
  * John Holder 06-Feb-1998 V2.0.2  j-holder@home.com Zstrict & Quetzal
  *
  * If you have problems with this interpreter and/or fix bugs in it,
  * please notify John Holder (j-holder@home.com) and he will add your
  * fix to the official JZIP distribution.
  */

#include "ztypes.h"

extern int GLOBALVER;

static void configure( zbyte_t, zbyte_t );

/*
  * main
  *
  * Initialise environment, start interpreter, clean up.
  */

int main( int argc, char *argv[] )
{
    process_arguments( argc, argv );

    configure( V1, V8 );

    initialize_screen(  );

    load_cache(  );

    z_restart(  );

    ( void ) interpret(  );

    unload_cache(  );

    close_story(  );

    close_script(  );

    reset_screen(  );

    exit( EXIT_SUCCESS );

    return ( 0 );

}                               /* main */

/*
  * configure
  *
  * Initialise global and type specific variables.
  *
  */

static void configure( zbyte_t min_version, zbyte_t max_version )
{
    zbyte_t header[PAGE_SIZE], second;

    read_page( 0, header );
    datap = header;

    h_type = get_byte( H_TYPE );

       GLOBALVER = h_type;

    if ( h_type < min_version || h_type > max_version ||
         ( get_byte( H_CONFIG ) & CONFIG_BYTE_SWAPPED ) )
       fatal( "Wrong game or version" );
    /*
     * if (h_type == V6 || h_type == V7)
     * fatal ("Unsupported zcode version.");
     */

    if ( h_type < V4 )
    {
       story_scaler = 2;
       story_shift = 1;
       property_mask = P3_MAX_PROPERTIES - 1;
       property_size_mask = 0xe0;
    }
    else if ( h_type < V8 )
    {
       story_scaler = 4;
       story_shift = 2;
       property_mask = P4_MAX_PROPERTIES - 1;
       property_size_mask = 0x3f;
    }
    else
    {
       story_scaler = 8;
       story_shift = 3;
       property_mask = P4_MAX_PROPERTIES - 1;
       property_size_mask = 0x3f;
    }

    h_config = get_byte( H_CONFIG );
    h_version = get_word( H_VERSION );
    h_data_size = get_word( H_DATA_SIZE );
    h_start_pc = get_word( H_START_PC );
    h_words_offset = get_word( H_WORDS_OFFSET );
    h_objects_offset = get_word( H_OBJECTS_OFFSET );
    h_globals_offset = get_word( H_GLOBALS_OFFSET );
    h_restart_size = get_word( H_RESTART_SIZE );
    h_flags = get_word( H_FLAGS );
    h_synonyms_offset = get_word( H_SYNONYMS_OFFSET );
    h_file_size = get_word( H_FILE_SIZE );
    if ( h_file_size == 0 )
       h_file_size = get_story_size(  );
    h_checksum = get_word( H_CHECKSUM );
    h_alternate_alphabet_offset = get_word( H_ALTERNATE_ALPHABET_OFFSET );

    if ( h_type >= V5 )
    {
       h_unicode_table = get_word( H_UNICODE_TABLE );
    }
    datap = NULL;

}                               /* configure */


------------------End jzip.c------------------------


Any help is greatly appreciated.


-Cooper