diff options
author | Gerald Combs <gerald@wireshark.org> | 2007-08-17 19:34:14 +0000 |
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committer | Gerald Combs <gerald@wireshark.org> | 2007-08-17 19:34:14 +0000 |
commit | 72daa58e1942578337835bb5493c168b80ad90ce (patch) | |
tree | 3addde2c71e52234ae9f5be95d5cd098bf6c78a6 /epan/frequency-utils.c | |
parent | 3d19c5130b310529e00a1726fb3951b304ca524e (diff) |
Instead of converting between 802.11 frequencies and channels umpteen
different ways, add a set of common conversion routines. Add a
"Frequency/Channel" column and fill it in where we can. Fix RSSI column
printing in PPI.
Fix up whitespace along the way.
svn path=/trunk/; revision=22538
Diffstat (limited to 'epan/frequency-utils.c')
-rw-r--r-- | epan/frequency-utils.c | 110 |
1 files changed, 110 insertions, 0 deletions
diff --git a/epan/frequency-utils.c b/epan/frequency-utils.c new file mode 100644 index 0000000000..aa04f1d4cf --- /dev/null +++ b/epan/frequency-utils.c @@ -0,0 +1,110 @@ +/* frequency-utils.c + * Frequency conversion utility definitions + * + * $Id$ + * + * Wireshark - Network traffic analyzer + * By Gerald Combs <gerald@wireshark.org> + * Copyright 2007 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + */ + +#ifdef HAVE_CONFIG_H +# include "config.h" +#endif + +#include <glib.h> + +#include "frequency-utils.h" + +typedef struct freq_cvt_s { + guint fmin; /* Minimum frequency in MHz */ + guint fmax; /* Maximum frequency in MHz */ + gint cmin; /* Minimum/base channel */ + gboolean is_bg; /* B/G channel? */ +} freq_cvt_t; + +#define FREQ_STEP 5 /* MHz. This seems to be consistent, thankfully */ + +static freq_cvt_t freq_cvt[] = { + { 2412, 2472, 1, TRUE }, + { 2484, 2484, 14, TRUE }, + { 5000, 5995, 0, FALSE }, + { 4920, 4995, 240, FALSE } +}; + +#define NUM_FREQ_CVT (sizeof(freq_cvt) / sizeof(freq_cvt_t)) +#define MAX_CHANNEL(fc) ( (gint) ((fc.fmax - fc.fmin) / FREQ_STEP) + fc.cmin ) + +/* + * Get channel number given a Frequency + */ +gint +ieee80211_mhz_to_chan(guint freq) { + int i; + + for (i = 0; i < NUM_FREQ_CVT; i++) { + if (freq >= freq_cvt[i].fmin && freq <= freq_cvt[i].fmax) { + return ((freq - freq_cvt[i].fmin) / FREQ_STEP) + freq_cvt[i].cmin; + } + } + return -1; +} + +/* + * Get Frequency given a Channel number + */ +guint +ieee80211_chan_to_mhz(gint chan, gboolean is_bg) { + int i; + + for (i = 0; i < NUM_FREQ_CVT; i++) { + if (is_bg == freq_cvt[i].is_bg && + chan >= freq_cvt[i].cmin && chan <= MAX_CHANNEL(freq_cvt[i])) { + return ((chan - freq_cvt[i].cmin) * FREQ_STEP) + freq_cvt[i].fmin; + } + } + return 0; +} + +/* + * Get channel representation string given a Frequency + */ +gchar* +ieee80211_mhz_to_str(guint freq){ + gint chan = ieee80211_mhz_to_chan(freq); + gboolean is_bg = FREQ_IS_BG(freq); + + if (chan < 0) { + return g_strdup_printf("%u", freq); + } else { + return g_strdup_printf("%u [%s %u]", freq, is_bg ? "BG" : "A", + chan); + } +} + +/* + * Editor modelines + * + * Local Variables: + * c-basic-offset: 4 + * tab-width: 8 + * indent-tabs-mode: nil + * End: + * + * ex: set shiftwidth=4 tabstop=8 expandtab + * :indentSize=4:tabSize=8:noTabs=true: + */ |