From ce81449ed9294f0104598762ce293c3521820987 Mon Sep 17 00:00:00 2001 From: Jakub Zawadzki Date: Thu, 11 Jul 2013 05:47:02 +0000 Subject: packet dissection now takes pointer to tvb instead of guint8 data implement frame_tvbuff, right now almost a copy of 'real' tvb. svn path=/trunk/; revision=50497 --- frame_tvbuff.c | 114 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 114 insertions(+) create mode 100644 frame_tvbuff.c (limited to 'frame_tvbuff.c') diff --git a/frame_tvbuff.c b/frame_tvbuff.c new file mode 100644 index 0000000000..5af5b3bc23 --- /dev/null +++ b/frame_tvbuff.c @@ -0,0 +1,114 @@ +/* frame_tvbuff.c + * Implements a tvbuff for frame + * + * $Id$ + * + * Wireshark - Network traffic analyzer + * By Gerald Combs + * 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. + */ + +#include "config.h" + +#include + +#include +#include +#include + +#include "frame_tvbuff.h" + +/* XXX, to read data with wtap_seek_read() we need: + * cf->wth, fdata->file_off, fdata->cap_len + * add when ready to structure below + */ + +struct tvb_frame { + struct tvbuff tvb; +}; + +static gsize +frame_sizeof(void) +{ + return sizeof(struct tvb_frame); +} + +static guint +frame_offset(const tvbuff_t *tvb _U_, const guint counter) +{ + return counter; +} + +static const struct tvb_ops tvb_frame_ops = { + frame_sizeof, /* size */ + NULL, /* free */ + frame_offset, /* offset */ + NULL, /* get_ptr */ + NULL, /* memcpy */ + NULL, /* find_guint8 */ + NULL, /* pbrk_guint8 */ +}; + +/* based on tvb_new_real_data() */ +tvbuff_t * +frame_tvbuff_new(const frame_data *fd, const guint8 *buf) +{ + tvbuff_t *tvb; + + tvb = tvb_new(&tvb_frame_ops); + + /* + * XXX - currently, the length arguments in + * tvbuff structure are signed, but the captured + * and reported length values are unsigned; this means + * that length values > 2^31 - 1 will appear as + * negative lengths + * + * Captured length values that large will already + * have been filtered out by the Wiretap modules + * (the file will be reported as corrupted), to + * avoid trying to allocate large chunks of data. + * + * Reported length values will not have been + * filtered out, and should not be filtered out, + * as those lengths are not necessarily invalid. + * + * For now, we clip the reported length at G_MAXINT + * + * (XXX, is this still a problem?) There was an exception when we call + * tvb_new_real_data() now there's no one + */ + + tvb->real_data = buf; + tvb->length = fd->cap_len; + tvb->reported_length = fd->pkt_len > G_MAXINT ? G_MAXINT : fd->pkt_len; + tvb->initialized = TRUE; + + /* + * This is the top-level real tvbuff for this data source, + * so its data source tvbuff is itself. + */ + tvb->ds_tvb = tvb; + + return tvb; +} + +tvbuff_t * +frame_tvbuff_new_buffer(const frame_data *fd, Buffer *buf) +{ + return frame_tvbuff_new(fd, buffer_start_ptr(buf)); +} -- cgit v1.2.3