1 /* lnstat.c: Unified linux network statistics
2 *
3 * Copyright (C) 2004 by Harald Welte <laforge@gnumonks.org>
4 *
5 * Development of this code was funded by Astaro AG, http://www.astaro.com/
6 *
7 * Based on original concept and ideas from predecessor rtstat.c:
8 *
9 * Copyright 2001 by Robert Olsson <robert.olsson@its.uu.se>
10 * Uppsala University, Sweden
11 *
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License as published by
14 * the Free Software Foundation; either version 2 of the License, or
15 * (at your option) any later version.
16 *
17 */
18
19 #include <unistd.h>
20 #include <stdio.h>
21 #include <stdlib.h>
22 #include <string.h>
23 #include <dirent.h>
24 #include <limits.h>
25 #include <time.h>
26
27 #include <sys/time.h>
28 #include <sys/types.h>
29
30 #include "lnstat.h"
31
32 /* size of temp buffer used to read lines from procfiles */
33 #define FGETS_BUF_SIZE 1024
34
35
36 #define RTSTAT_COMPAT_LINE "entries in_hit in_slow_tot in_no_route in_brd in_martian_dst in_martian_src out_hit out_slow_tot out_slow_mc gc_total gc_ignored gc_goal_miss gc_dst_overflow in_hlist_search out_hlist_search\n"
37
38 /* Read (and summarize for SMP) the different stats vars. */
scan_lines(struct lnstat_file * lf,int i)39 static int scan_lines(struct lnstat_file *lf, int i)
40 {
41 int j, num_lines = 0;
42
43 for (j = 0; j < lf->num_fields; j++)
44 lf->fields[j].values[i] = 0;
45
46 while(!feof(lf->fp)) {
47 char buf[FGETS_BUF_SIZE];
48 char *ptr = buf;
49
50 num_lines++;
51
52 fgets(buf, sizeof(buf)-1, lf->fp);
53 gettimeofday(&lf->last_read, NULL);
54
55 for (j = 0; j < lf->num_fields; j++) {
56 unsigned long f = strtoul(ptr, &ptr, 16);
57 if (j == 0)
58 lf->fields[j].values[i] = f;
59 else
60 lf->fields[j].values[i] += f;
61 }
62 }
63 return num_lines;
64 }
65
time_after(struct timeval * last,struct timeval * tout,struct timeval * now)66 static int time_after(struct timeval *last,
67 struct timeval *tout,
68 struct timeval *now)
69 {
70 if (now->tv_sec > last->tv_sec + tout->tv_sec)
71 return 1;
72
73 if (now->tv_sec == last->tv_sec + tout->tv_sec) {
74 if (now->tv_usec > last->tv_usec + tout->tv_usec)
75 return 1;
76 }
77
78 return 0;
79 }
80
lnstat_update(struct lnstat_file * lnstat_files)81 int lnstat_update(struct lnstat_file *lnstat_files)
82 {
83 struct lnstat_file *lf;
84 char buf[FGETS_BUF_SIZE];
85 struct timeval tv;
86
87 gettimeofday(&tv, NULL);
88
89 for (lf = lnstat_files; lf; lf = lf->next) {
90 if (time_after(&lf->last_read, &lf->interval, &tv)) {
91 int i;
92 struct lnstat_field *lfi;
93
94 rewind(lf->fp);
95 if (!lf->compat) {
96 /* skip first line */
97 fgets(buf, sizeof(buf)-1, lf->fp);
98 }
99 scan_lines(lf, 1);
100
101 for (i = 0, lfi = &lf->fields[i];
102 i < lf->num_fields; i++, lfi = &lf->fields[i]) {
103 if (i == 0)
104 lfi->result = lfi->values[1];
105 else
106 lfi->result = (lfi->values[1]-lfi->values[0])
107 / lf->interval.tv_sec;
108 }
109
110 rewind(lf->fp);
111 fgets(buf, sizeof(buf)-1, lf->fp);
112 scan_lines(lf, 0);
113 }
114 }
115
116 return 0;
117 }
118
119 /* scan first template line and fill in per-field data structures */
__lnstat_scan_fields(struct lnstat_file * lf,char * buf)120 static int __lnstat_scan_fields(struct lnstat_file *lf, char *buf)
121 {
122 char *tok;
123 int i;
124
125 tok = strtok(buf, " \t\n");
126 for (i = 0; i < LNSTAT_MAX_FIELDS_PER_LINE; i++) {
127 lf->fields[i].file = lf;
128 strncpy(lf->fields[i].name, tok, LNSTAT_MAX_FIELD_NAME_LEN);
129 /* has to be null-terminate since we initialize to zero
130 * and field size is NAME_LEN + 1 */
131 tok = strtok(NULL, " \t\n");
132 if (!tok) {
133 lf->num_fields = i+1;
134 return 0;
135 }
136 }
137 return 0;
138 }
139
lnstat_scan_fields(struct lnstat_file * lf)140 static int lnstat_scan_fields(struct lnstat_file *lf)
141 {
142 char buf[FGETS_BUF_SIZE];
143
144 rewind(lf->fp);
145 fgets(buf, sizeof(buf)-1, lf->fp);
146
147 return __lnstat_scan_fields(lf, buf);
148 }
149
150 /* fake function emulating lnstat_scan_fields() for old kernels */
lnstat_scan_compat_rtstat_fields(struct lnstat_file * lf)151 static int lnstat_scan_compat_rtstat_fields(struct lnstat_file *lf)
152 {
153 char buf[FGETS_BUF_SIZE];
154
155 strncpy(buf, RTSTAT_COMPAT_LINE, sizeof(buf)-1);
156
157 return __lnstat_scan_fields(lf, buf);
158 }
159
160 /* find out whether string 'name; is in given string array */
name_in_array(const int num,const char ** arr,const char * name)161 static int name_in_array(const int num, const char **arr, const char *name)
162 {
163 int i;
164 for (i = 0; i < num; i++) {
165 if (!strcmp(arr[i], name))
166 return 1;
167 }
168 return 0;
169 }
170
171 /* allocate lnstat_file and open given file */
alloc_and_open(const char * path,const char * file)172 static struct lnstat_file *alloc_and_open(const char *path, const char *file)
173 {
174 struct lnstat_file *lf;
175
176 /* allocate */
177 lf = malloc(sizeof(*lf));
178 if (!lf)
179 return NULL;
180
181 /* initialize */
182 memset(lf, 0, sizeof(*lf));
183
184 /* de->d_name is guaranteed to be <= NAME_MAX */
185 strcpy(lf->basename, file);
186 strcpy(lf->path, path);
187 strcat(lf->path, "/");
188 strcat(lf->path, lf->basename);
189
190 /* initialize to default */
191 lf->interval.tv_sec = 1;
192
193 /* open */
194 lf->fp = fopen(lf->path, "r");
195 if (!lf->fp) {
196 free(lf);
197 return NULL;
198 }
199
200 return lf;
201 }
202
203
204 /* lnstat_scan_dir - find and parse all available statistics files/fields */
lnstat_scan_dir(const char * path,const int num_req_files,const char ** req_files)205 struct lnstat_file *lnstat_scan_dir(const char *path, const int num_req_files,
206 const char **req_files)
207 {
208 DIR *dir;
209 struct lnstat_file *lnstat_files = NULL;
210 struct dirent *de;
211
212 if (!path)
213 path = PROC_NET_STAT;
214
215 dir = opendir(path);
216 if (!dir) {
217 struct lnstat_file *lf;
218 /* Old kernel, before /proc/net/stat was introduced */
219 fprintf(stderr, "Your kernel doesn't have lnstat support. ");
220
221 /* we only support rtstat, not multiple files */
222 if (num_req_files >= 2) {
223 fputc('\n', stderr);
224 return NULL;
225 }
226
227 /* we really only accept rt_cache */
228 if (num_req_files && !name_in_array(num_req_files,
229 req_files, "rt_cache")) {
230 fputc('\n', stderr);
231 return NULL;
232 }
233
234 fprintf(stderr, "Fallback to old rtstat-only operation\n");
235
236 lf = alloc_and_open("/proc/net", "rt_cache_stat");
237 if (!lf)
238 return NULL;
239 lf->compat = 1;
240 strncpy(lf->basename, "rt_cache", sizeof(lf->basename));
241
242 /* FIXME: support for old files */
243 if (lnstat_scan_compat_rtstat_fields(lf) < 0)
244 return NULL;
245
246 lf->next = lnstat_files;
247 lnstat_files = lf;
248 return lnstat_files;
249 }
250
251 while ((de = readdir(dir))) {
252 struct lnstat_file *lf;
253
254 if (de->d_type != DT_REG)
255 continue;
256
257 if (num_req_files && !name_in_array(num_req_files,
258 req_files, de->d_name))
259 continue;
260
261 lf = alloc_and_open(path, de->d_name);
262 if (!lf)
263 return NULL;
264
265 /* fill in field structure */
266 if (lnstat_scan_fields(lf) < 0)
267 return NULL;
268
269 /* prepend to global list */
270 lf->next = lnstat_files;
271 lnstat_files = lf;
272 }
273 closedir(dir);
274
275 return lnstat_files;
276 }
277
lnstat_dump(FILE * outfd,struct lnstat_file * lnstat_files)278 int lnstat_dump(FILE *outfd, struct lnstat_file *lnstat_files)
279 {
280 struct lnstat_file *lf;
281
282 for (lf = lnstat_files; lf; lf = lf->next) {
283 int i;
284
285 fprintf(outfd, "%s:\n", lf->path);
286
287 for (i = 0; i < lf->num_fields; i++)
288 fprintf(outfd, "\t%2u: %s\n", i+1, lf->fields[i].name);
289
290 }
291 return 0;
292 }
293
lnstat_find_field(struct lnstat_file * lnstat_files,const char * name)294 struct lnstat_field *lnstat_find_field(struct lnstat_file *lnstat_files,
295 const char *name)
296 {
297 struct lnstat_file *lf;
298 struct lnstat_field *ret = NULL;
299 const char *colon = strchr(name, ':');
300 char *file;
301 const char *field;
302
303 if (colon) {
304 file = strndup(name, colon-name);
305 field = colon+1;
306 } else {
307 file = NULL;
308 field = name;
309 }
310
311 for (lf = lnstat_files; lf; lf = lf->next) {
312 int i;
313
314 if (file && strcmp(file, lf->basename))
315 continue;
316
317 for (i = 0; i < lf->num_fields; i++) {
318 if (!strcmp(field, lf->fields[i].name)) {
319 ret = &lf->fields[i];
320 goto out;
321 }
322 }
323 }
324 out:
325 if (file)
326 free(file);
327
328 return ret;
329 }
330