wireshark/epan/tvbuff-int.h

/* tvbuff-int.h
 *
 * Structures that most TVB users should not be accessing directly.
 *
 * $Id$
 *
 * Wireshark - Network traffic analyzer
 * By Gerald Combs <gerald@wireshark.org>
 * Copyright 1998 Gerald Combs
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#ifndef __TVBUFF_INT_H__
#define __TVBUFF_INT_H__

struct tvbuff;

struct tvb_ops {
	gsize (*tvb_size)(void);
	void (*tvb_free)(struct tvbuff *tvb);
	guint (*tvb_offset)(const struct tvbuff *tvb, guint counter);
	const guint8 *(*tvb_get_ptr)(struct tvbuff *tvb, guint abs_offset, guint abs_length);
	void *(*tvb_memcpy)(struct tvbuff *tvb, void *target, guint offset, guint length);

	gint (*tvb_find_guint8)(tvbuff_t *tvb, guint abs_offset, guint limit, guint8 needle);
	gint (*tvb_pbrk_guint8)(tvbuff_t *tvb, guint abs_offset, guint limit, const guint8 *needles, guchar *found_needle);
};

typedef struct {
	/** The backing tvbuff_t */
	struct tvbuff	*tvb;

	/** The offset of 'tvb' to which I'm privy */
	guint		offset;
	/** The length of 'tvb' to which I'm privy */
	guint		length;

} tvb_backing_t;

typedef struct {
	GSList		*tvbs;

	/* Used for quick testing to see if this
	 * is the tvbuff that a COMPOSITE is
	 * interested in. */
	guint		*start_offsets;
	guint		*end_offsets;

} tvb_comp_t;

/*
 * Tvbuff flags.
 */
#define TVBUFF_FRAGMENT		0x00000001	/* this is a fragment */

struct tvbuff {
	/* Doubly linked list pointers */
	tvbuff_t                *next;
	tvbuff_t                *previous;

	/* Record-keeping */
	const struct tvb_ops   *ops;
	gboolean		initialized;
	guint			flags;
	struct tvbuff		*ds_tvb;  /**< data source top-level tvbuff */

	/** We're either a TVBUFF_REAL_DATA or a
	 * TVBUFF_SUBSET that has a backing buffer that
	 * has real_data != NULL, or a TVBUFF_COMPOSITE
	 * which has flattened its data due to a call
	 * to tvb_get_ptr().
	 */
	const guint8		*real_data;

	/** Length of virtual buffer (and/or real_data). */
	guint			length;

	/** Reported length. */
	guint			reported_length;

	/* Offset from beginning of first TVBUFF_REAL. */
	gint			raw_offset;
};

struct tvb_real {
	struct tvbuff tvb;

	/** Func to call when actually freed */
	tvbuff_free_cb_t	free_cb;
};

struct tvb_subset {
	struct tvbuff tvb;

	tvb_backing_t	subset;
};

struct tvb_composite {
	struct tvbuff tvb;

	tvb_comp_t	composite;
};


#endif