aboutsummaryrefslogtreecommitdiffstats
path: root/plugin_netdev.c
blob: a989a0f4df7d49ae07eb7b12d7c8404a4d31209a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
/* $Id: plugin_netdev.c,v 1.13 2005/01/18 06:30:23 reinelt Exp $
 *
 * plugin for /proc/net/dev parsing
 *
 * Copyright (C) 2003 Michael Reinelt <reinelt@eunet.at>
 * Copyright (C) 2004 The LCD4Linux Team <lcd4linux-devel@users.sourceforge.net>
 *
 * This file is part of LCD4Linux.
 *
 * LCD4Linux 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, or (at your option)
 * any later version.
 *
 * LCD4Linux 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., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 *
 * $Log: plugin_netdev.c,v $
 * Revision 1.13  2005/01/18 06:30:23  reinelt
 * added (C) to all copyright statements
 *
 * Revision 1.12  2004/06/26 12:05:00  reinelt
 *
 * uh-oh... the last CVS log message messed up things a lot...
 *
 * Revision 1.11  2004/06/26 09:27:21  reinelt
 *
 * added '-W' to CFLAGS
 * changed all C++ comments to C ones
 * cleaned up a lot of signed/unsigned mistakes
 *
 * Revision 1.10  2004/06/17 10:58:58  reinelt
 *
 * changed plugin_netdev to use the new fast hash model
 *
 * Revision 1.9  2004/06/17 06:23:43  reinelt
 *
 * hash handling rewritten to solve performance issues
 *
 * Revision 1.8  2004/05/27 03:39:47  reinelt
 *
 * changed function naming scheme to plugin::function
 *
 * Revision 1.7  2004/03/11 06:39:59  reinelt
 * big patch from Martin:
 * - reuse filehandles
 * - memory leaks fixed
 * - earlier busy-flag checking with HD44780
 * - reuse memory for strings in RESULT and hash
 * - netdev_fast to wavid time-consuming regex
 *
 * Revision 1.6  2004/03/03 04:44:16  reinelt
 * changes (cosmetics?) to the big patch from Martin
 * hash patch un-applied
 *
 * Revision 1.5  2004/03/03 03:47:04  reinelt
 * big patch from Martin Hejl:
 * - use qprintf() where appropriate
 * - save CPU cycles on gettimeofday()
 * - add quit() functions to free allocated memory
 * - fixed lots of memory leaks
 *
 * Revision 1.4  2004/02/15 07:23:04  reinelt
 * bug in netdev parsing fixed
 *
 * Revision 1.3  2004/02/01 19:37:40  reinelt
 * got rid of every strtok() incarnation.
 *
 * Revision 1.2  2004/01/29 04:40:02  reinelt
 * every .c file includes "config.h" now
 *
 * Revision 1.1  2004/01/25 05:30:09  reinelt
 * plugin_netdev for parsing /proc/net/dev added
 *
 */

/* 
 * exported functions:
 *
 * int plugin_init_netdev (void)
 *  adds functions to access /proc/net/dev
 *
 */


#include "config.h"

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <ctype.h>
#include <errno.h>

#include "debug.h"
#include "plugin.h"
#include "qprintf.h"
#include "hash.h"


static HASH NetDev;
static FILE *Stream = NULL;
static char *DELIMITER = " :|\t\n";

static int parse_netdev (void)
{
  int age;
  int row, col;
  static int first_time = 1;
  
  /* reread every 10 msec only */
  age = hash_age(&NetDev, NULL);
  if (age > 0 && age <= 10) return 0;
  
  if (Stream == NULL) Stream = fopen("/proc/net/dev", "r");
  if (Stream == NULL) {
    error ("fopen(/proc/net/dev) failed: %s", strerror(errno));
    return -1;
  }

  rewind(Stream);    
  row = 0;
  
  while (!feof(Stream)) {
    char buffer[256];
    char dev[16];
    char *beg, *end;
    unsigned int len;
    
    if (fgets (buffer, sizeof(buffer), Stream) == NULL) break;
    
    switch (++row) {
      
    case 1:
      /* skip row 1 */
      continue;
      
    case 2:
      /* row 2 used for headers */
      if (first_time) {
	char *RxTx = strrchr(buffer, '|');
	first_time = 0;
	col = 0;
	beg = buffer;
	while (beg) {
	  char key[32];
	  
	  while (strchr(DELIMITER, *beg)) beg++;
	  if ((end = strpbrk(beg, DELIMITER)) != NULL) *end = '\0';
	  qprintf(key, sizeof(key), "%s_%s", beg < RxTx ? "Rx" : "Tx", beg);
	  hash_set_column (&NetDev, col++, key);
	  beg = end ? end + 1 : NULL;
	}
      }
      continue;

    default:
      /* fetch interface name (1st column) as key */
      beg = buffer;
      while (*beg && *beg == ' ') beg++;
      end = beg + 1;
      while (*end && *end != ':') end++;
      len = end - beg;
      if (len >= sizeof(dev)) len = sizeof(dev)-1;
      strncpy (dev, beg, len);
      dev[len] = '\0';
      
      hash_put_delta (&NetDev, dev, buffer); 
    }
  }
  
  return 0;
}  

static void my_netdev (RESULT *result, RESULT *arg1, RESULT *arg2, RESULT *arg3)
{
  char *dev, *key;
  int delay;
  double value;
  
  if (parse_netdev()<0) {
    SetResult(&result, R_STRING, ""); 
    return;
  }

  dev   = R2S(arg1);
  key   = R2S(arg2);
  delay = R2N(arg3);
  
  value  = hash_get_regex(&NetDev, dev, key, delay);
  
  SetResult(&result, R_NUMBER, &value); 
}

static void my_netdev_fast(RESULT *result, RESULT *arg1, RESULT *arg2, RESULT *arg3)
{
  char *dev, *key;
  int delay;
  double value;
  
  if (parse_netdev()<0) {
    SetResult(&result, R_STRING, ""); 
    return;
  }

  dev   = R2S(arg1);
  key   = R2S(arg2);
  delay = R2N(arg3);
  
  value  = hash_get_delta(&NetDev, dev, key, delay);
  
  SetResult(&result, R_NUMBER, &value); 
}


int plugin_init_netdev (void)
{
  hash_create(&NetDev);
  hash_set_delimiter (&NetDev, " :|\t\n");

  AddFunction ("netdev",       3, my_netdev);
  AddFunction ("netdev::fast", 3, my_netdev_fast);
  return 0;
}

void plugin_exit_netdev(void) 
{
  if(Stream!=NULL) {
    fclose (Stream);
    Stream=NULL;
  }
  hash_destroy(&NetDev);
}