epan/tvbuff_real.c

   1 /* tvbuff_real.c
   2  *
   3  * $Id$
   4  *
   5  * Copyright (c) 2000 by Gilbert Ramirez <gram@alumni.rice.edu>
   6  *
   7  * Wireshark - Network traffic analyzer
   8  * By Gerald Combs <gerald@wireshark.org>
   9  * Copyright 1998 Gerald Combs
  10  *
  11  * This program is free software; you can redistribute it and/or
  12  * modify it under the terms of the GNU General Public License
  13  * as published by the Free Software Foundation; either version 2
  14  * of the License, or (at your option) any later version.
  15  *
  16  * This program is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19  * GNU General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU General Public License
  22  * along with this program; if not, write to the Free Software
  23  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  24  */
  25
  26 #include "config.h"
  27
  28 #include <epan/emem.h>
  29
  30 #include "tvbuff.h"
  31 #include "tvbuff-int.h"
  32 #include "proto.h"      /* XXX - only used for DISSECTOR_ASSERT, probably a new header file? */
  33 #include "exceptions.h"
  34
  35 struct tvb_real {
  36         struct tvbuff tvb;
  37
  38         /** Func to call when actually freed */
  39         tvbuff_free_cb_t        free_cb;
  40 };
  41
  42 static void
  43 real_free(tvbuff_t *tvb)
  44 {
  45         struct tvb_real *real_tvb = (struct tvb_real *) tvb;
  46
  47         if (real_tvb->free_cb) {
  48                 /*
  49                  * XXX - do this with a union?
  50                  */
  51                 real_tvb->free_cb((gpointer)tvb->real_data);
  52         }
  53 }
  54
  55 static guint
  56 real_offset(const tvbuff_t *tvb _U_, const guint counter)
  57 {
  58         return counter;
  59 }
  60
  61 static const struct tvb_ops tvb_real_ops = {
  62         sizeof(struct tvb_real), /* size */
  63
  64         real_free,            /* free */
  65         real_offset,          /* offset */
  66         NULL,                 /* get_ptr */
  67         NULL,                 /* memcpy */
  68         NULL,                 /* find_guint8 */
  69         NULL,                 /* pbrk_guint8 */
  70         NULL,                 /* clone */
  71 };
  72
  73 tvbuff_t *
  74 tvb_new_real_data(const guint8* data, const guint length, const gint reported_length)
  75 {
  76         tvbuff_t *tvb;
  77         struct tvb_real *real_tvb;
  78
  79         THROW_ON(reported_length < -1, ReportedBoundsError);
  80
  81         tvb = tvb_new(&tvb_real_ops);
  82
  83         tvb->real_data       = data;
  84         tvb->length          = length;
  85         tvb->reported_length = reported_length;
  86         tvb->initialized     = TRUE;
  87
  88         /*
  89          * This is the top-level real tvbuff for this data source,
  90          * so its data source tvbuff is itself.
  91          */
  92         tvb->ds_tvb = tvb;
  93
  94         real_tvb = (struct tvb_real *) tvb;
  95         real_tvb->free_cb = NULL;
  96
  97         return tvb;
  98 }
  99
 100 void
 101 tvb_set_free_cb(tvbuff_t *tvb, const tvbuff_free_cb_t func)
 102 {
 103         struct tvb_real *real_tvb = (struct tvb_real *) tvb;
 104
 105         DISSECTOR_ASSERT(tvb);
 106         DISSECTOR_ASSERT(tvb->ops == &tvb_real_ops);
 107         real_tvb->free_cb = func;
 108 }
 109
 110 void
 111 tvb_set_child_real_data_tvbuff(tvbuff_t *parent, tvbuff_t *child)
 112 {
 113         DISSECTOR_ASSERT(parent && child);
 114         DISSECTOR_ASSERT(parent->initialized);
 115         DISSECTOR_ASSERT(child->initialized);
 116         DISSECTOR_ASSERT(child->ops == &tvb_real_ops);
 117         tvb_add_to_chain(parent, child);
 118 }
 119
 120 tvbuff_t *
 121 tvb_new_child_real_data(tvbuff_t *parent, const guint8* data, const guint length, const gint reported_length)
 122 {
 123         tvbuff_t *tvb = tvb_new_real_data(data, length, reported_length);
 124
 125         tvb_set_child_real_data_tvbuff(parent, tvb);
 126
 127         return tvb;
 128 }