src/gallium/auxiliary/hud/hud_nic.c - platform/external/mesa3d - Gitiles

 /**************************************************************************
  *
  * Copyright (C) 2016 Steven Toth <stoth@kernellabs.com>
  * Copyright (C) 2016 Zodiac Inflight Innovations
  * All Rights Reserved.
  *
  * Permission is hereby granted, free of charge, to any person obtaining a
  * copy of this software and associated documentation files (the
  * "Software"), to deal in the Software without restriction, including
  * without limitation the rights to use, copy, modify, merge, publish,
  * distribute, sub license, and/or sell copies of the Software, and to
  * permit persons to whom the Software is furnished to do so, subject to
  * the following conditions:
  *
  * The above copyright notice and this permission notice (including the
  * next paragraph) shall be included in all copies or substantial portions
  * of the Software.
  *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
  * IN NO EVENT SHALL THE AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR
  * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
  * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
  * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  *
  **************************************************************************/

 #if HAVE_GALLIUM_EXTRA_HUD

 /* Purpose: Reading network interface RX/TX throughput per second,
  * displaying on the HUD.
  */

 #include "hud/hud_private.h"
 #include "util/list.h"
 #include "os/os_time.h"
 #include "util/u_memory.h"
 #include <stdio.h>
 #include <unistd.h>
 #include <dirent.h>
 #include <stdlib.h>
 #include <unistd.h>
 #include <inttypes.h>
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <sys/socket.h>
 #include <sys/ioctl.h>
 #include <linux/wireless.h>

 #define LOCAL_DEBUG 0

 struct nic_info
 {
    struct list_head list;
    int mode;
    char name[64];
    uint64_t speedMbps;
    int is_wireless;

    char throughput_filename[128];
    uint64_t last_time;
    uint64_t last_nic_bytes;
 };

 /* TODO: We don't handle dynamic NIC arrival or removal.
  * Static globals specific to this HUD category.
  */
 static int gnic_count = 0;
 static struct list_head gnic_list;

 static struct nic_info *
 find_nic_by_name(const char *n, int mode)
 {
    list_for_each_entry(struct nic_info, nic, &gnic_list, list) {
       if (nic->mode != mode)
          continue;

       if (strcasecmp(nic->name, n) == 0)
          return nic;
    }
    return 0;
 }

 static int
 get_file_value(const char *fname, uint64_t *value)
 {
    FILE *fh = fopen(fname, "r");
    if (!fh)
       return -1;
    if (fscanf(fh, "%" PRIu64 "", value) != 0) {
       /* Error */
    }
    fclose(fh);
    return 0;
 }

 static boolean
 get_nic_bytes(const char *fn, uint64_t *bytes)
 {
    if (get_file_value(fn, bytes) < 0)
       return FALSE;

    return TRUE;
 }

 static void
 query_wifi_bitrate(const struct nic_info *nic, uint64_t *bitrate)
 {
    int sockfd;
    struct iw_statistics stats;
    struct iwreq req;

    memset(&stats, 0, sizeof(stats));
    memset(&req, 0, sizeof(req));

    strcpy(req.ifr_name, nic->name);
    req.u.data.pointer = &stats;
    req.u.data.flags = 1;
    req.u.data.length = sizeof(struct iw_statistics);

    /* Any old socket will do, and a datagram socket is pretty cheap */
    if ((sockfd = socket(AF_INET, SOCK_DGRAM, 0)) == -1) {
       fprintf(stderr, "Unable to create socket for %s\n", nic->name);
       return;
    }

    if (ioctl(sockfd, SIOCGIWRATE, &req) == -1) {
       fprintf(stderr, "Error performing SIOCGIWSTATS on %s\n", nic->name);
       close(sockfd);
       return;
    }
    *bitrate = req.u.bitrate.value;

    close(sockfd);
 }

 static void
 query_nic_rssi(const struct nic_info *nic, uint64_t *leveldBm)
 {
    int sockfd;
    struct iw_statistics stats;
    struct iwreq req;

    memset(&stats, 0, sizeof(stats));
    memset(&req, 0, sizeof(req));

    strcpy(req.ifr_name, nic->name);
    req.u.data.pointer = &stats;
    req.u.data.flags = 1;
    req.u.data.length = sizeof(struct iw_statistics);

    if (nic->mode != NIC_RSSI_DBM)
       return;

    /* Any old socket will do, and a datagram socket is pretty cheap */
    if ((sockfd = socket(AF_INET, SOCK_DGRAM, 0)) == -1) {
       fprintf(stderr, "Unable to create socket for %s\n", nic->name);
       return;
    }

    /* Perform the ioctl */
    if (ioctl(sockfd, SIOCGIWSTATS, &req) == -1) {
       fprintf(stderr, "Error performing SIOCGIWSTATS on %s\n", nic->name);
       close(sockfd);
       return;
    }
    *leveldBm = ((char) stats.qual.level * -1);

    close(sockfd);

 #if LOCAL_DEBUG
    printf("NIC signal level%s is %d%s.\n",
           (stats.qual.updated & IW_QUAL_DBM ? " (in dBm)" : ""),
           (char) stats.qual.level,
           (stats.qual.updated & IW_QUAL_LEVEL_UPDATED ? " (updated)" : ""));
 #endif
 }

 static void
 query_nic_load(struct hud_graph *gr)
 {
    /* The framework calls us at a regular but indefined period,
     * not once per second, compensate the statistics accordingly.
     */

    struct nic_info *nic = gr->query_data;
    uint64_t now = os_time_get();

    if (nic->last_time) {
       if (nic->last_time + gr->pane->period <= now) {
          switch (nic->mode) {
          case NIC_DIRECTION_RX:
          case NIC_DIRECTION_TX:
             {
                uint64_t bytes;
                get_nic_bytes(nic->throughput_filename, &bytes);
                uint64_t nic_mbps =
                   ((bytes - nic->last_nic_bytes) / 1000000) * 8;

                float speedMbps = nic->speedMbps;
                float periodMs = gr->pane->period / 1000;
                float bits = nic_mbps;
                float period_factor = periodMs / 1000;
                float period_speed = speedMbps * period_factor;
                float pct = (bits / period_speed) * 100;

                /* Scaling bps with a narrow time period into a second,
                 * potentially suffers from routing errors at higher
                 * periods. Eg 104%. Compensate.
                 */
                if (pct > 100)
                   pct = 100;
                hud_graph_add_value(gr, (uint64_t) pct);

                nic->last_nic_bytes = bytes;
             }
             break;
          case NIC_RSSI_DBM:
             {
                uint64_t leveldBm = 0;
                query_nic_rssi(nic, &leveldBm);
                hud_graph_add_value(gr, leveldBm);
             }
             break;
          }

          nic->last_time = now;
       }
    }
    else {
       /* initialize */
       switch (nic->mode) {
       case NIC_DIRECTION_RX:
       case NIC_DIRECTION_TX:
          get_nic_bytes(nic->throughput_filename, &nic->last_nic_bytes);
          break;
       case NIC_RSSI_DBM:
          break;
       }

       nic->last_time = now;
    }
 }

 static void
 free_query_data(void *p)
 {
    struct nic_info *nic = (struct nic_info *) p;
    list_del(&nic->list);
    FREE(nic);
 }

 /**
   * Create and initialize a new object for a specific network interface dev.
   * \param  pane  parent context.
   * \param  nic_name  logical block device name, EG. eth0.
   * \param  mode  query type (NIC_DIRECTION_RX/WR/RSSI) statistics.
   */
 void
 hud_nic_graph_install(struct hud_pane *pane, const char *nic_name,
                       unsigned int mode)
 {
    struct hud_graph *gr;
    struct nic_info *nic;

    int num_nics = hud_get_num_nics(0);
    if (num_nics <= 0)
       return;

 #if LOCAL_DEBUG
    printf("%s(%s, %s) - Creating HUD object\n", __func__, nic_name,
           mode == NIC_DIRECTION_RX ? "RX" :
           mode == NIC_DIRECTION_TX ? "TX" :
           mode == NIC_RSSI_DBM ? "RSSI" : "UNDEFINED");
 #endif

    nic = find_nic_by_name(nic_name, mode);
    if (!nic)
       return;

    gr = CALLOC_STRUCT(hud_graph);
    if (!gr)
       return;

    nic->mode = mode;
    if (nic->mode == NIC_DIRECTION_RX) {
       snprintf(gr->name, sizeof(gr->name), "%s-rx-%lldMbps", nic->name,
          nic->speedMbps);
    }
    else if (nic->mode == NIC_DIRECTION_TX) {
       snprintf(gr->name, sizeof(gr->name), "%s-tx-%lldMbps", nic->name,
          nic->speedMbps);
    }
    else if (nic->mode == NIC_RSSI_DBM)
       snprintf(gr->name, sizeof(gr->name), "%s-rssi", nic->name);
    else
       return;

    gr->query_data = nic;
    gr->query_new_value = query_nic_load;

    /* Don't use free() as our callback as that messes up Gallium's
     * memory debugger.  Use simple free_query_data() wrapper.
     */
    gr->free_query_data = free_query_data;

    hud_pane_add_graph(pane, gr);
    hud_pane_set_max_value(pane, 100);
 }

 static int
 is_wireless_nic(const char *dirbase)
 {
    struct stat stat_buf;

    /* Check if its a wireless card */
    char fn[256];
    snprintf(fn, sizeof(fn), "%s/wireless", dirbase);
    if (stat(fn, &stat_buf) == 0)
       return 1;

    return 0;
 }

 static void
 query_nic_bitrate(struct nic_info *nic, const char *dirbase)
 {
    struct stat stat_buf;

    /* Check if its a wireless card */
    char fn[256];
    snprintf(fn, sizeof(fn), "%s/wireless", dirbase);
    if (stat(fn, &stat_buf) == 0) {
       /* we're a wireless nic */
       query_wifi_bitrate(nic, &nic->speedMbps);
       nic->speedMbps /= 1000000;
    }
    else {
       /* Must be a wired nic */
       snprintf(fn, sizeof(fn), "%s/speed", dirbase);
       get_file_value(fn, &nic->speedMbps);
    }
 }

 /**
   * Initialize internal object arrays and display NIC HUD help.
   * \param  displayhelp  true if the list of detected devices should be
                          displayed on the console.
   * \return  number of detected network interface devices.
   */
 int
 hud_get_num_nics(bool displayhelp)
 {
    struct dirent *dp;
    struct stat stat_buf;
    struct nic_info *nic;
    char name[64];

    /* Return the number if network interfaces. */
    if (gnic_count)
       return gnic_count;

    /* Scan /sys/block, for every object type we support, create and
     * persist an object to represent its different statistics.
     */
    list_inithead(&gnic_list);
    DIR *dir = opendir("/sys/class/net/");
    if (!dir)
       return 0;

    while ((dp = readdir(dir)) != NULL) {

       /* Avoid 'lo' and '..' and '.' */
       if (strlen(dp->d_name) <= 2)
          continue;

       char basename[256];
       snprintf(basename, sizeof(basename), "/sys/class/net/%s", dp->d_name);
       snprintf(name, sizeof(name), "%s/statistics/rx_bytes", basename);
       if (stat(name, &stat_buf) < 0)
          continue;

       if (!S_ISREG(stat_buf.st_mode))
          continue;              /* Not a regular file */

       int is_wireless = is_wireless_nic(basename);

       /* Add the RX object */
       nic = CALLOC_STRUCT(nic_info);
       strcpy(nic->name, dp->d_name);
       snprintf(nic->throughput_filename, sizeof(nic->throughput_filename),
          "%s/statistics/rx_bytes", basename);
       nic->mode = NIC_DIRECTION_RX;
       nic->is_wireless = is_wireless;
       query_nic_bitrate(nic, basename);

       list_addtail(&nic->list, &gnic_list);
       gnic_count++;

       /* Add the TX object */
       nic = CALLOC_STRUCT(nic_info);
       strcpy(nic->name, dp->d_name);
       snprintf(nic->throughput_filename,
          sizeof(nic->throughput_filename),
          "/sys/class/net/%s/statistics/tx_bytes", dp->d_name);
       nic->mode = NIC_DIRECTION_TX;
       nic->is_wireless = is_wireless;

       query_nic_bitrate(nic, basename);

       list_addtail(&nic->list, &gnic_list);
       gnic_count++;

       if (nic->is_wireless) {
          /* RSSI Support */
          nic = CALLOC_STRUCT(nic_info);
          strcpy(nic->name, dp->d_name);
          snprintf(nic->throughput_filename,
             sizeof(nic->throughput_filename),
             "/sys/class/net/%s/statistics/tx_bytes", dp->d_name);
          nic->mode = NIC_RSSI_DBM;

          query_nic_bitrate(nic, basename);

          list_addtail(&nic->list, &gnic_list);
          gnic_count++;
       }

    }

    list_for_each_entry(struct nic_info, nic, &gnic_list, list) {
       char line[64];
       snprintf(line, sizeof(line), "    nic-%s-%s",
               nic->mode == NIC_DIRECTION_RX ? "rx" :
               nic->mode == NIC_DIRECTION_TX ? "tx" :
               nic->mode == NIC_RSSI_DBM ? "rssi" : "undefined", nic->name);

       puts(line);

    }

    return gnic_count;
 }

 #endif /* HAVE_GALLIUM_EXTRA_HUD */
	/**************************************************************************
	*
	* Copyright (C) 2016 Steven Toth <stoth@kernellabs.com>
	* Copyright (C) 2016 Zodiac Inflight Innovations
	* All Rights Reserved.
	*
	* Permission is hereby granted, free of charge, to any person obtaining a
	* copy of this software and associated documentation files (the
	* "Software"), to deal in the Software without restriction, including
	* without limitation the rights to use, copy, modify, merge, publish,
	* distribute, sub license, and/or sell copies of the Software, and to
	* permit persons to whom the Software is furnished to do so, subject to
	* the following conditions:
	*
	* The above copyright notice and this permission notice (including the
	* next paragraph) shall be included in all copies or substantial portions
	* of the Software.
	*
	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
	* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
	* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
	* IN NO EVENT SHALL THE AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR
	* ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
	* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
	* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
	*
	**************************************************************************/

	#if HAVE_GALLIUM_EXTRA_HUD

	/* Purpose: Reading network interface RX/TX throughput per second,
	* displaying on the HUD.
	*/

	#include "hud/hud_private.h"
	#include "util/list.h"
	#include "os/os_time.h"
	#include "util/u_memory.h"
	#include <stdio.h>
	#include <unistd.h>
	#include <dirent.h>
	#include <stdlib.h>
	#include <unistd.h>
	#include <inttypes.h>
	#include <sys/types.h>
	#include <sys/stat.h>
	#include <sys/socket.h>
	#include <sys/ioctl.h>
	#include <linux/wireless.h>

	#define LOCAL_DEBUG 0

	struct nic_info
	{
	struct list_head list;
	int mode;
	char name[64];
	uint64_t speedMbps;
	int is_wireless;

	char throughput_filename[128];
	uint64_t last_time;
	uint64_t last_nic_bytes;
	};

	/* TODO: We don't handle dynamic NIC arrival or removal.
	* Static globals specific to this HUD category.
	*/
	static int gnic_count = 0;
	static struct list_head gnic_list;

	static struct nic_info *
	find_nic_by_name(const char *n, int mode)
	{
	list_for_each_entry(struct nic_info, nic, &gnic_list, list) {
	if (nic->mode != mode)
	continue;

	if (strcasecmp(nic->name, n) == 0)
	return nic;
	}
	return 0;
	}

	static int
	get_file_value(const char fname, uint64_t value)
	{
	FILE *fh = fopen(fname, "r");
	if (!fh)
	return -1;
	if (fscanf(fh, "%" PRIu64 "", value) != 0) {
	/* Error */
	}
	fclose(fh);
	return 0;
	}

	static boolean
	get_nic_bytes(const char fn, uint64_t bytes)
	{
	if (get_file_value(fn, bytes) < 0)
	return FALSE;

	return TRUE;
	}

	static void
	query_wifi_bitrate(const struct nic_info nic, uint64_t bitrate)
	{
	int sockfd;
	struct iw_statistics stats;
	struct iwreq req;

	memset(&stats, 0, sizeof(stats));
	memset(&req, 0, sizeof(req));

	strcpy(req.ifr_name, nic->name);
	req.u.data.pointer = &stats;
	req.u.data.flags = 1;
	req.u.data.length = sizeof(struct iw_statistics);

	/* Any old socket will do, and a datagram socket is pretty cheap */
	if ((sockfd = socket(AF_INET, SOCK_DGRAM, 0)) == -1) {
	fprintf(stderr, "Unable to create socket for %s\n", nic->name);
	return;
	}

	if (ioctl(sockfd, SIOCGIWRATE, &req) == -1) {
	fprintf(stderr, "Error performing SIOCGIWSTATS on %s\n", nic->name);
	close(sockfd);
	return;
	}
	*bitrate = req.u.bitrate.value;

	close(sockfd);
	}

	static void
	query_nic_rssi(const struct nic_info nic, uint64_t leveldBm)
	{
	int sockfd;
	struct iw_statistics stats;
	struct iwreq req;

	memset(&stats, 0, sizeof(stats));
	memset(&req, 0, sizeof(req));

	strcpy(req.ifr_name, nic->name);
	req.u.data.pointer = &stats;
	req.u.data.flags = 1;
	req.u.data.length = sizeof(struct iw_statistics);

	if (nic->mode != NIC_RSSI_DBM)
	return;

	/* Any old socket will do, and a datagram socket is pretty cheap */
	if ((sockfd = socket(AF_INET, SOCK_DGRAM, 0)) == -1) {
	fprintf(stderr, "Unable to create socket for %s\n", nic->name);
	return;
	}

	/* Perform the ioctl */
	if (ioctl(sockfd, SIOCGIWSTATS, &req) == -1) {
	fprintf(stderr, "Error performing SIOCGIWSTATS on %s\n", nic->name);
	close(sockfd);
	return;
	}
	leveldBm = ((char) stats.qual.level -1);

	close(sockfd);

	#if LOCAL_DEBUG
	printf("NIC signal level%s is %d%s.\n",
	(stats.qual.updated & IW_QUAL_DBM ? " (in dBm)" : ""),
	(char) stats.qual.level,
	(stats.qual.updated & IW_QUAL_LEVEL_UPDATED ? " (updated)" : ""));
	#endif
	}

	static void
	query_nic_load(struct hud_graph *gr)
	{
	/* The framework calls us at a regular but indefined period,
	* not once per second, compensate the statistics accordingly.
	*/

	struct nic_info *nic = gr->query_data;
	uint64_t now = os_time_get();

	if (nic->last_time) {
	if (nic->last_time + gr->pane->period <= now) {
	switch (nic->mode) {
	case NIC_DIRECTION_RX:
	case NIC_DIRECTION_TX:
	{
	uint64_t bytes;
	get_nic_bytes(nic->throughput_filename, &bytes);
	uint64_t nic_mbps =
	((bytes - nic->last_nic_bytes) / 1000000) * 8;

	float speedMbps = nic->speedMbps;
	float periodMs = gr->pane->period / 1000;
	float bits = nic_mbps;
	float period_factor = periodMs / 1000;
	float period_speed = speedMbps * period_factor;
	float pct = (bits / period_speed) * 100;

	/* Scaling bps with a narrow time period into a second,
	* potentially suffers from routing errors at higher
	* periods. Eg 104%. Compensate.
	*/
	if (pct > 100)
	pct = 100;
	hud_graph_add_value(gr, (uint64_t) pct);

	nic->last_nic_bytes = bytes;
	}
	break;
	case NIC_RSSI_DBM:
	{
	uint64_t leveldBm = 0;
	query_nic_rssi(nic, &leveldBm);
	hud_graph_add_value(gr, leveldBm);
	}
	break;
	}

	nic->last_time = now;
	}
	}
	else {
	/* initialize */
	switch (nic->mode) {
	case NIC_DIRECTION_RX:
	case NIC_DIRECTION_TX:
	get_nic_bytes(nic->throughput_filename, &nic->last_nic_bytes);
	break;
	case NIC_RSSI_DBM:
	break;
	}

	nic->last_time = now;
	}
	}

	static void
	free_query_data(void *p)
	{
	struct nic_info nic = (struct nic_info ) p;
	list_del(&nic->list);
	FREE(nic);
	}

	/**
	* Create and initialize a new object for a specific network interface dev.
	* \param pane parent context.
	* \param nic_name logical block device name, EG. eth0.
	* \param mode query type (NIC_DIRECTION_RX/WR/RSSI) statistics.
	*/
	void
	hud_nic_graph_install(struct hud_pane pane, const char nic_name,
	unsigned int mode)
	{
	struct hud_graph *gr;
	struct nic_info *nic;

	int num_nics = hud_get_num_nics(0);
	if (num_nics <= 0)
	return;

	#if LOCAL_DEBUG
	printf("%s(%s, %s) - Creating HUD object\n", __func__, nic_name,
	mode == NIC_DIRECTION_RX ? "RX" :
	mode == NIC_DIRECTION_TX ? "TX" :
	mode == NIC_RSSI_DBM ? "RSSI" : "UNDEFINED");
	#endif

	nic = find_nic_by_name(nic_name, mode);
	if (!nic)
	return;

	gr = CALLOC_STRUCT(hud_graph);
	if (!gr)
	return;

	nic->mode = mode;
	if (nic->mode == NIC_DIRECTION_RX) {
	snprintf(gr->name, sizeof(gr->name), "%s-rx-%lldMbps", nic->name,
	nic->speedMbps);
	}
	else if (nic->mode == NIC_DIRECTION_TX) {
	snprintf(gr->name, sizeof(gr->name), "%s-tx-%lldMbps", nic->name,
	nic->speedMbps);
	}
	else if (nic->mode == NIC_RSSI_DBM)
	snprintf(gr->name, sizeof(gr->name), "%s-rssi", nic->name);
	else
	return;

	gr->query_data = nic;
	gr->query_new_value = query_nic_load;

	/* Don't use free() as our callback as that messes up Gallium's
	* memory debugger. Use simple free_query_data() wrapper.
	*/
	gr->free_query_data = free_query_data;

	hud_pane_add_graph(pane, gr);
	hud_pane_set_max_value(pane, 100);
	}

	static int
	is_wireless_nic(const char *dirbase)
	{
	struct stat stat_buf;

	/* Check if its a wireless card */
	char fn[256];
	snprintf(fn, sizeof(fn), "%s/wireless", dirbase);
	if (stat(fn, &stat_buf) == 0)
	return 1;

	return 0;
	}

	static void
	query_nic_bitrate(struct nic_info nic, const char dirbase)
	{
	struct stat stat_buf;

	/* Check if its a wireless card */
	char fn[256];
	snprintf(fn, sizeof(fn), "%s/wireless", dirbase);
	if (stat(fn, &stat_buf) == 0) {
	/* we're a wireless nic */
	query_wifi_bitrate(nic, &nic->speedMbps);
	nic->speedMbps /= 1000000;
	}
	else {
	/* Must be a wired nic */
	snprintf(fn, sizeof(fn), "%s/speed", dirbase);
	get_file_value(fn, &nic->speedMbps);
	}
	}

	/**
	* Initialize internal object arrays and display NIC HUD help.
	* \param displayhelp true if the list of detected devices should be
	displayed on the console.
	* \return number of detected network interface devices.
	*/
	int
	hud_get_num_nics(bool displayhelp)
	{
	struct dirent *dp;
	struct stat stat_buf;
	struct nic_info *nic;
	char name[64];

	/* Return the number if network interfaces. */
	if (gnic_count)
	return gnic_count;

	/* Scan /sys/block, for every object type we support, create and
	* persist an object to represent its different statistics.
	*/
	list_inithead(&gnic_list);
	DIR *dir = opendir("/sys/class/net/");
	if (!dir)
	return 0;

	while ((dp = readdir(dir)) != NULL) {

	/* Avoid 'lo' and '..' and '.' */
	if (strlen(dp->d_name) <= 2)
	continue;

	char basename[256];
	snprintf(basename, sizeof(basename), "/sys/class/net/%s", dp->d_name);
	snprintf(name, sizeof(name), "%s/statistics/rx_bytes", basename);
	if (stat(name, &stat_buf) < 0)
	continue;

	if (!S_ISREG(stat_buf.st_mode))
	continue; /* Not a regular file */

	int is_wireless = is_wireless_nic(basename);

	/* Add the RX object */
	nic = CALLOC_STRUCT(nic_info);
	strcpy(nic->name, dp->d_name);
	snprintf(nic->throughput_filename, sizeof(nic->throughput_filename),
	"%s/statistics/rx_bytes", basename);
	nic->mode = NIC_DIRECTION_RX;
	nic->is_wireless = is_wireless;
	query_nic_bitrate(nic, basename);

	list_addtail(&nic->list, &gnic_list);
	gnic_count++;

	/* Add the TX object */
	nic = CALLOC_STRUCT(nic_info);
	strcpy(nic->name, dp->d_name);
	snprintf(nic->throughput_filename,
	sizeof(nic->throughput_filename),
	"/sys/class/net/%s/statistics/tx_bytes", dp->d_name);
	nic->mode = NIC_DIRECTION_TX;
	nic->is_wireless = is_wireless;

	query_nic_bitrate(nic, basename);

	list_addtail(&nic->list, &gnic_list);
	gnic_count++;

	if (nic->is_wireless) {
	/* RSSI Support */
	nic = CALLOC_STRUCT(nic_info);
	strcpy(nic->name, dp->d_name);
	snprintf(nic->throughput_filename,
	sizeof(nic->throughput_filename),
	"/sys/class/net/%s/statistics/tx_bytes", dp->d_name);
	nic->mode = NIC_RSSI_DBM;

	query_nic_bitrate(nic, basename);

	list_addtail(&nic->list, &gnic_list);
	gnic_count++;
	}

	}

	list_for_each_entry(struct nic_info, nic, &gnic_list, list) {
	char line[64];
	snprintf(line, sizeof(line), " nic-%s-%s",
	nic->mode == NIC_DIRECTION_RX ? "rx" :
	nic->mode == NIC_DIRECTION_TX ? "tx" :
	nic->mode == NIC_RSSI_DBM ? "rssi" : "undefined", nic->name);

	puts(line);

	}

	return gnic_count;
	}

	#endif /* HAVE_GALLIUM_EXTRA_HUD */