linux/net/batman-adv/gateway_common.c
Sven Eckelmann b4e1705417 batman-adv: Reduce usage of char
char was used in different places to store information without really
using the characteristics of that data type or by ignoring the fact that
char has not a well defined signedness.

Signed-off-by: Sven Eckelmann <sven@narfation.org>
2011-06-20 11:37:18 +02:00

179 lines
4.1 KiB
C

/*
* Copyright (C) 2009-2011 B.A.T.M.A.N. contributors:
*
* Marek Lindner
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of version 2 of the GNU General Public
* License as published by the Free Software Foundation.
*
* 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 "main.h"
#include "gateway_common.h"
#include "gateway_client.h"
/* calculates the gateway class from kbit */
static void kbit_to_gw_bandwidth(int down, int up, long *gw_srv_class)
{
int mdown = 0, tdown, tup, difference;
uint8_t sbit, part;
*gw_srv_class = 0;
difference = 0x0FFFFFFF;
/* test all downspeeds */
for (sbit = 0; sbit < 2; sbit++) {
for (part = 0; part < 16; part++) {
tdown = 32 * (sbit + 2) * (1 << part);
if (abs(tdown - down) < difference) {
*gw_srv_class = (sbit << 7) + (part << 3);
difference = abs(tdown - down);
mdown = tdown;
}
}
}
/* test all upspeeds */
difference = 0x0FFFFFFF;
for (part = 0; part < 8; part++) {
tup = ((part + 1) * (mdown)) / 8;
if (abs(tup - up) < difference) {
*gw_srv_class = (*gw_srv_class & 0xF8) | part;
difference = abs(tup - up);
}
}
}
/* returns the up and downspeeds in kbit, calculated from the class */
void gw_bandwidth_to_kbit(uint8_t gw_srv_class, int *down, int *up)
{
int sbit = (gw_srv_class & 0x80) >> 7;
int dpart = (gw_srv_class & 0x78) >> 3;
int upart = (gw_srv_class & 0x07);
if (!gw_srv_class) {
*down = 0;
*up = 0;
return;
}
*down = 32 * (sbit + 2) * (1 << dpart);
*up = ((upart + 1) * (*down)) / 8;
}
static bool parse_gw_bandwidth(struct net_device *net_dev, char *buff,
int *up, int *down)
{
int ret, multi = 1;
char *slash_ptr, *tmp_ptr;
long ldown, lup;
slash_ptr = strchr(buff, '/');
if (slash_ptr)
*slash_ptr = 0;
if (strlen(buff) > 4) {
tmp_ptr = buff + strlen(buff) - 4;
if (strnicmp(tmp_ptr, "mbit", 4) == 0)
multi = 1024;
if ((strnicmp(tmp_ptr, "kbit", 4) == 0) ||
(multi > 1))
*tmp_ptr = '\0';
}
ret = strict_strtol(buff, 10, &ldown);
if (ret) {
bat_err(net_dev,
"Download speed of gateway mode invalid: %s\n",
buff);
return false;
}
*down = ldown * multi;
/* we also got some upload info */
if (slash_ptr) {
multi = 1;
if (strlen(slash_ptr + 1) > 4) {
tmp_ptr = slash_ptr + 1 - 4 + strlen(slash_ptr + 1);
if (strnicmp(tmp_ptr, "mbit", 4) == 0)
multi = 1024;
if ((strnicmp(tmp_ptr, "kbit", 4) == 0) ||
(multi > 1))
*tmp_ptr = '\0';
}
ret = strict_strtol(slash_ptr + 1, 10, &lup);
if (ret) {
bat_err(net_dev,
"Upload speed of gateway mode invalid: "
"%s\n", slash_ptr + 1);
return false;
}
*up = lup * multi;
}
return true;
}
ssize_t gw_bandwidth_set(struct net_device *net_dev, char *buff, size_t count)
{
struct bat_priv *bat_priv = netdev_priv(net_dev);
long gw_bandwidth_tmp = 0;
int up = 0, down = 0;
bool ret;
ret = parse_gw_bandwidth(net_dev, buff, &up, &down);
if (!ret)
goto end;
if ((!down) || (down < 256))
down = 2000;
if (!up)
up = down / 5;
kbit_to_gw_bandwidth(down, up, &gw_bandwidth_tmp);
/**
* the gw bandwidth we guessed above might not match the given
* speeds, hence we need to calculate it back to show the number
* that is going to be propagated
**/
gw_bandwidth_to_kbit((uint8_t)gw_bandwidth_tmp, &down, &up);
gw_deselect(bat_priv);
bat_info(net_dev, "Changing gateway bandwidth from: '%i' to: '%ld' "
"(propagating: %d%s/%d%s)\n",
atomic_read(&bat_priv->gw_bandwidth), gw_bandwidth_tmp,
(down > 2048 ? down / 1024 : down),
(down > 2048 ? "MBit" : "KBit"),
(up > 2048 ? up / 1024 : up),
(up > 2048 ? "MBit" : "KBit"));
atomic_set(&bat_priv->gw_bandwidth, gw_bandwidth_tmp);
end:
return count;
}