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/* packet-wap.c
*
* Utility routines for WAP dissectors
*
* Wireshark - Network traffic analyzer
* By Gerald Combs <gerald@wireshark.org>
* Copyright 1998 Gerald Combs
*
* WAP dissector based on original work by Ben Fowler
* Updated by Neil Hunter <neil.hunter@energis-squared.com>
* WTLS support by Alexandre P. Ferreira (Splice IP)
*
* SPDX-License-Identifier: GPL-2.0-or-later
*/
#include "config.h"
#include <epan/packet.h>
#include "packet-wap.h"
/*
* Accessor to retrieve variable length int as used in WAP protocol.
* The value is encoded in the lower 7 bits. If the top bit is set, then the
* value continues into the next byte.
* The octetCount parameter holds the number of bytes read in order to return
* the final value. Can be pre-initialised to start at offset+count.
*/
guint
tvb_get_guintvar (tvbuff_t *tvb, guint offset, guint *octetCount, packet_info *pinfo, expert_field *ei)
{
guint value = 0;
guint octet;
guint counter = 0;
char cont = 1;
#ifdef DEBUG
if (octetCount != NULL)
{
fprintf (stderr, "dissect_wap: Starting tvb_get_guintvar at offset %d, count=%d\n", offset, *octetCount);
/* counter = *octetCount; */
}
else
{
fprintf (stderr, "dissect_wap: Starting tvb_get_guintvar at offset %d, count=NULL\n", offset);
}
#endif
while (cont != 0)
{
value <<= 7; /* Value only exists in 7 of the 8 bits */
octet = tvb_get_guint8 (tvb, offset+counter);
counter += 1;
value += (octet & 0x7F);
cont = (octet & 0x80);
#ifdef DEBUG
fprintf (stderr, "dissect_wap: computing: octet is %d (0x%02x), count=%d, value=%d, cont=%d\n",
octet, octet, counter, value, cont);
#endif
}
if (counter > 5) {
proto_tree_add_expert(NULL, pinfo, ei, tvb, offset, counter);
value = 0;
}
if (octetCount != NULL)
{
*octetCount = counter;
#ifdef DEBUG
fprintf (stderr, "dissect_wap: Leaving tvb_get_guintvar count=%d, value=%u\n", *octetCount, value);
#endif
}
return (value);
}
/*
* Editor modelines - http://www.wireshark.org/tools/modelines.html
*
* Local variables:
* c-basic-offset: 4
* tab-width: 8
* indent-tabs-mode: nil
* End:
*
* vi: set shiftwidth=4 tabstop=8 expandtab:
* :indentSize=4:tabSize=8:noTabs=true:
*/
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