/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * Copyright by the Board of Trustees of the University of Illinois.         *
 * All rights reserved.                                                      *
 *                                                                           *
 * This file is part of HDF5.  The full HDF5 copyright notice, including     *
 * terms governing use, modification, and redistribution, is contained in    *
 * the files COPYING and Copyright.html.  COPYING can be found at the root   *
 * of the source code distribution tree; Copyright.html can be found at the  *
 * root level of an installed copy of the electronic HDF5 document set and   *
 * is linked from the top-level documents page.  It can also be found at     *
 * http://hdf.ncsa.uiuc.edu/HDF5/doc/Copyright.html.  If you do not have     *
 * access to either file, you may request a copy from hdfhelp@ncsa.uiuc.edu. *
 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

/*
 * Programmer:	Robb Matzke <matzke@llnl.gov>
 *		Wednesday, April  1, 1998
 *
 * Purpose:	Functions that operate on a shared message.  The shared
 *		message doesn't ever actually appear in the object header as
 *		a normal message.  Instead, if a message is shared, the
 *		H5O_FLAG_SHARED bit is set and the message body is that
 *		defined here for H5O_SHARED.  The message ID is the ID of the
 *		pointed-to message and the pointed-to message is stored in
 *		the global heap.
 */

#define H5O_PACKAGE	/*suppress error about including H5Opkg	  */

#include "H5private.h"
#include "H5Eprivate.h"
#include "H5MMprivate.h"
#include "H5Opkg.h"             /* Object header functions                  */

static void *H5O_shared_decode (H5F_t*, hid_t dxpl_id, const uint8_t*, H5O_shared_t *sh);
static herr_t H5O_shared_encode (H5F_t*, uint8_t*, const void*);
static size_t H5O_shared_size (H5F_t*, const void*);
static herr_t H5O_shared_debug (H5F_t*, hid_t dxpl_id, const void*, FILE*, int, int);

/* This message derives from H5O */
const H5O_class_t H5O_SHARED[1] = {{
    H5O_SHARED_ID,	    	/*message id number			*/
    "shared",		    	/*message name for debugging		*/
    sizeof(H5O_shared_t), 	/*native message size			*/
    H5O_shared_decode,	    	/*decode method				*/
    H5O_shared_encode,	    	/*encode method				*/
    NULL,		    	/*no copy method			*/
    H5O_shared_size,	    	/*size method				*/
    NULL,		    	/*no reset method			*/
    NULL,		        /*no free method			*/
    NULL,		        /* file delete method		*/
    NULL,			/*get share method			*/
    NULL, 			/*set share method			*/
    H5O_shared_debug,	    	/*debug method				*/
}};

#define H5O_SHARED_VERSION	1

/* Interface initialization */
#define PABLO_MASK	H5O_shared_mask
static int interface_initialize_g = 0;
#define INTERFACE_INIT  NULL


/*-------------------------------------------------------------------------
 * Function:	H5O_shared_decode
 *
 * Purpose:	Decodes a shared object message and returns it.
 *
 * Return:	Success:	Ptr to a new shared object message.
 *
 *		Failure:	NULL
 *
 * Programmer:	Robb Matzke
 *              Thursday, April  2, 1998
 *
 * Modifications:
 *	Robb Matzke, 1998-07-20
 *	Added a version number to the beginning of the message.
 *-------------------------------------------------------------------------
 */
static void *
H5O_shared_decode (H5F_t *f, hid_t UNUSED dxpl_id, const uint8_t *buf, H5O_shared_t UNUSED *sh)
{
    H5O_shared_t	*mesg=NULL;
    unsigned		flags, version;
    void                *ret_value;     /* Return value */
    
    FUNC_ENTER_NOAPI(H5O_shared_decode, NULL);

    /* Check args */
    assert (f);
    assert (buf);
    assert (!sh);

    /* Decode */
    if (NULL==(mesg = H5MM_calloc (sizeof *mesg)))
	HGOTO_ERROR (H5E_RESOURCE, H5E_NOSPACE, NULL, "memory allocation failed");

    /* Version */
    version = *buf++;
    if (version!=H5O_SHARED_VERSION)
	HGOTO_ERROR(H5E_OHDR, H5E_CANTLOAD, NULL, "bad version number for shared object message");

    /* Flags */
    flags = *buf++;
    mesg->in_gh = (flags & 0x01);

    /* Reserved */
    buf += 6;

    /* Body */
    if (mesg->in_gh) {
	H5F_addr_decode (f, &buf, &(mesg->u.gh.addr));
	INT32DECODE (buf, mesg->u.gh.idx);
    } else {
	H5G_ent_decode (f, &buf, &(mesg->u.ent));
    }

    /* Set return value */
    ret_value=mesg;

done:
    if(ret_value==NULL) {
        if(mesg!=NULL)
            H5MM_xfree(mesg);
    } /* end if */

    FUNC_LEAVE_NOAPI(ret_value);
}


/*-------------------------------------------------------------------------
 * Function:	H5O_shared_encode
 *
 * Purpose:	Encodes message _MESG into buffer BUF.
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Robb Matzke
 *              Thursday, April  2, 1998
 *
 * Modifications:
 *	Robb Matzke, 1998-07-20
 *	Added a version number to the beginning of the message.
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5O_shared_encode (H5F_t *f, uint8_t *buf/*out*/, const void *_mesg)
{
    const H5O_shared_t	*mesg = (const H5O_shared_t *)_mesg;
    unsigned		flags;
    herr_t ret_value=SUCCEED;   /* Return value */
    
    FUNC_ENTER_NOAPI(H5O_shared_encode, FAIL);

    /* Check args */
    assert (f);
    assert (buf);
    assert (mesg);

    /* Encode */
    *buf++ = H5O_SHARED_VERSION;
    flags = mesg->in_gh ? 0x01 : 0x00;
    *buf++ = flags;
    *buf++ = 0; /*reserved 1*/
    *buf++ = 0; /*reserved 2*/
    *buf++ = 0; /*reserved 3*/
    *buf++ = 0; /*reserved 4*/
    *buf++ = 0; /*reserved 5*/
    *buf++ = 0; /*reserved 6*/

    if (mesg->in_gh) {
	H5F_addr_encode (f, &buf, mesg->u.gh.addr);
	INT32ENCODE (buf, mesg->u.gh.idx);
    } else {
	H5G_ent_encode (f, &buf, &(mesg->u.ent));
    }

done:
    FUNC_LEAVE_NOAPI(ret_value);
}


/*-------------------------------------------------------------------------
 * Function:	H5O_shared_size
 *
 * Purpose:	Returns the length of a shared object message.
 *
 * Return:	Success:	Length
 *
 *		Failure:	0
 *
 * Programmer:	Robb Matzke
 *              Thursday, April  2, 1998
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
static size_t
H5O_shared_size (H5F_t *f, const void UNUSED *_mesg)
{
    size_t	ret_value;
    
    FUNC_ENTER_NOAPI(H5O_shared_size, 0);

    ret_value = 1 +				/*the flags field		*/
	   7 +				/*reserved			*/
	   MAX (H5F_SIZEOF_ADDR(f)+4,	/*sharing via global heap	*/
		H5G_SIZEOF_ENTRY(f));	/*sharing by another obj hdr	*/

done:
    FUNC_LEAVE_NOAPI(ret_value);
}


/*-------------------------------------------------------------------------
 * Function:	H5O_shared_debug
 *
 * Purpose:	Prints debugging info for the message
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Robb Matzke
 *              Thursday, April  2, 1998
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5O_shared_debug (H5F_t UNUSED *f, hid_t dxpl_id, const void *_mesg,
		  FILE *stream, int indent, int fwidth)
{
    const H5O_shared_t	*mesg = (const H5O_shared_t *)_mesg;
    herr_t ret_value=SUCCEED;   /* Return value */

    FUNC_ENTER_NOAPI(H5O_shared_debug, FAIL);

    /* Check args */
    assert (f);
    assert (mesg);
    assert (stream);
    assert (indent>=0);
    assert (fwidth>=0);

    if (mesg->in_gh) {
	HDfprintf (stream, "%*s%-*s %s\n", indent, "", fwidth,
		   "Sharing method",
		   "Global heap");
	HDfprintf (stream, "%*s%-*s %a\n", indent, "", fwidth,
		   "Collection address:",
		   mesg->u.gh.addr);
	HDfprintf (stream, "%*s%-*s %d\n", indent, "", fwidth,
		   "Object ID within collection:",
		   mesg->u.gh.idx);
    } else {
	HDfprintf (stream, "%*s%-*s %s\n", indent, "", fwidth,
		   "Sharing method",
		   "Obj Hdr");
	H5G_ent_debug (f, dxpl_id, &(mesg->u.ent), stream, indent, fwidth,
		       HADDR_UNDEF);
    }
    
done:
    FUNC_LEAVE_NOAPI(ret_value);
}