release/src/router/miniupnpd/linux/getifstats.c

   1 /* $Id: getifstats.c,v 1.11 2012/04/06 15:26:45 nanard Exp $ */
   2 /* MiniUPnP project
   3  * http://miniupnp.free.fr/ or http://miniupnp.tuxfamily.org/
   4  * (c) 2006-2012 Thomas Bernard
   5  * This software is subject to the conditions detailed
   6  * in the LICENCE file provided within the distribution */
   7
   8 #include <stdio.h>
   9 #include <stdlib.h>
  10 #include <syslog.h>
  11 #include <string.h>
  12 #include <time.h>
  13
  14 #include "../config.h"
  15 #include "../getifstats.h"
  16
  17 int
  18 getifstats(const char * ifname, struct ifdata * data)
  19 {
  20         FILE *f;
  21         char line[512];
  22         char * p;
  23         int i;
  24         int r = -1;
  25         char fname[64];
  26 #ifdef ENABLE_GETIFSTATS_CACHING
  27         static time_t cache_timestamp = 0;
  28         static struct ifdata cache_data;
  29         time_t current_time;
  30 #endif
  31         if(!data)
  32                 return -1;
  33         data->baudrate = 4200000;       /* that is the answer */
  34         data->opackets = 0;
  35         data->ipackets = 0;
  36         data->obytes = 0;
  37         data->ibytes = 0;
  38         if(!ifname || ifname[0]=='\0')
  39                 return -1;
  40 #ifdef ENABLE_GETIFSTATS_CACHING
  41         current_time = time(NULL);
  42         if(current_time == ((time_t)-1)) {
  43                 syslog(LOG_ERR, "getifstats() : time() error : %m");
  44         } else {
  45                 if(current_time < cache_timestamp + GETIFSTATS_CACHING_DURATION) {
  46                         /* return cached data */
  47                         memcpy(data, &cache_data, sizeof(struct ifdata));
  48                         return 0;
  49                 }
  50         }
  51 #endif
  52         f = fopen("/proc/net/dev", "r");
  53         if(!f) {
  54                 syslog(LOG_ERR, "getifstats() : cannot open /proc/net/dev : %m");
  55                 return -1;
  56         }
  57         /* discard the two header lines */
  58         if(!fgets(line, sizeof(line), f) || !fgets(line, sizeof(line), f)) {
  59                 syslog(LOG_ERR, "getifstats() : error reading /proc/net/dev : %m");
  60         }
  61         while(fgets(line, sizeof(line), f)) {
  62                 p = line;
  63                 while(*p==' ') p++;
  64                 i = 0;
  65                 while(ifname[i] == *p) {
  66                         p++; i++;
  67                 }
  68                 /* TODO : how to handle aliases ? */
  69                 if(ifname[i] || *p != ':')
  70                         continue;
  71                 p++;
  72                 while(*p==' ') p++;
  73                 data->ibytes = strtoul(p, &p, 0);
  74                 while(*p==' ') p++;
  75                 data->ipackets = strtoul(p, &p, 0);
  76                 /* skip 6 columns */
  77                 for(i=6; i>0 && *p!='\0'; i--) {
  78                         while(*p==' ') p++;
  79                         while(*p!=' ' && *p) p++;
  80                 }
  81                 while(*p==' ') p++;
  82                 data->obytes = strtoul(p, &p, 0);
  83                 while(*p==' ') p++;
  84                 data->opackets = strtoul(p, &p, 0);
  85                 r = 0;
  86                 break;
  87         }
  88         fclose(f);
  89         /* get interface speed */
  90         snprintf(fname, sizeof(fname), "/sys/class/net/%s/speed", ifname);
  91         f = fopen(fname, "r");
  92         if(f) {
  93                 if(fgets(line, sizeof(line), f)) {
  94                         i = atoi(line); /* 65535 means unknown */
  95                         if(i > 0 && i < 65535)
  96                                 data->baudrate = 1000000*i;
  97                 }
  98                 fclose(f);
  99         } else {
 100                 syslog(LOG_INFO, "cannot read %s file : %m", fname);
 101         }
 102 #ifdef ENABLE_GETIFSTATS_CACHING
 103         if(r==0 && current_time!=((time_t)-1)) {
 104                 /* cache the new data */
 105                 cache_timestamp = current_time;
 106                 memcpy(&cache_data, data, sizeof(struct ifdata));
 107         }
 108 #endif
 109         return r;
 110 }
 111