1 /* lnstat.c: Unified linux network statistics 2 * 3 * Copyright (C) 2004 by Harald Welte <laforge (at) 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 (at) 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. */ 39 static int scan_lines(struct lnstat_file *lf, int i) 40 { 41 char buf[FGETS_BUF_SIZE]; 42 int j, num_lines = 0; 43 44 for (j = 0; j < lf->num_fields; j++) 45 lf->fields[j].values[i] = 0; 46 47 rewind(lf->fp); 48 /* skip first line */ 49 if (!lf->compat && !fgets(buf, sizeof(buf)-1, lf->fp)) 50 return -1; 51 52 while(!feof(lf->fp) && fgets(buf, sizeof(buf)-1, lf->fp)) { 53 char *ptr = buf; 54 55 num_lines++; 56 57 gettimeofday(&lf->last_read, NULL); 58 59 for (j = 0; j < lf->num_fields; j++) { 60 unsigned long f = strtoul(ptr, &ptr, 16); 61 if (j == 0) 62 lf->fields[j].values[i] = f; 63 else 64 lf->fields[j].values[i] += f; 65 } 66 } 67 return num_lines; 68 } 69 70 static int time_after(struct timeval *last, 71 struct timeval *tout, 72 struct timeval *now) 73 { 74 if (now->tv_sec > last->tv_sec + tout->tv_sec) 75 return 1; 76 77 if (now->tv_sec == last->tv_sec + tout->tv_sec) { 78 if (now->tv_usec > last->tv_usec + tout->tv_usec) 79 return 1; 80 } 81 82 return 0; 83 } 84 85 int lnstat_update(struct lnstat_file *lnstat_files) 86 { 87 struct lnstat_file *lf; 88 struct timeval tv; 89 90 gettimeofday(&tv, NULL); 91 92 for (lf = lnstat_files; lf; lf = lf->next) { 93 if (time_after(&lf->last_read, &lf->interval, &tv)) { 94 int i; 95 struct lnstat_field *lfi; 96 97 scan_lines(lf, 1); 98 99 for (i = 0, lfi = &lf->fields[i]; 100 i < lf->num_fields; i++, lfi = &lf->fields[i]) { 101 if (i == 0) 102 lfi->result = lfi->values[1]; 103 else 104 lfi->result = (lfi->values[1]-lfi->values[0]) 105 / lf->interval.tv_sec; 106 } 107 108 scan_lines(lf, 0); 109 } 110 } 111 112 return 0; 113 } 114 115 /* scan first template line and fill in per-field data structures */ 116 static int __lnstat_scan_fields(struct lnstat_file *lf, char *buf) 117 { 118 char *tok; 119 int i; 120 121 tok = strtok(buf, " \t\n"); 122 for (i = 0; i < LNSTAT_MAX_FIELDS_PER_LINE; i++) { 123 lf->fields[i].file = lf; 124 strncpy(lf->fields[i].name, tok, LNSTAT_MAX_FIELD_NAME_LEN); 125 /* has to be null-terminate since we initialize to zero 126 * and field size is NAME_LEN + 1 */ 127 tok = strtok(NULL, " \t\n"); 128 if (!tok) { 129 lf->num_fields = i+1; 130 return 0; 131 } 132 } 133 return 0; 134 } 135 136 static int lnstat_scan_fields(struct lnstat_file *lf) 137 { 138 char buf[FGETS_BUF_SIZE]; 139 140 rewind(lf->fp); 141 if (!fgets(buf, sizeof(buf)-1, lf->fp)) 142 return -1; 143 144 return __lnstat_scan_fields(lf, buf); 145 } 146 147 /* fake function emulating lnstat_scan_fields() for old kernels */ 148 static int lnstat_scan_compat_rtstat_fields(struct lnstat_file *lf) 149 { 150 char buf[FGETS_BUF_SIZE]; 151 152 strncpy(buf, RTSTAT_COMPAT_LINE, sizeof(buf)-1); 153 154 return __lnstat_scan_fields(lf, buf); 155 } 156 157 /* find out whether string 'name; is in given string array */ 158 static int name_in_array(const int num, const char **arr, const char *name) 159 { 160 int i; 161 for (i = 0; i < num; i++) { 162 if (!strcmp(arr[i], name)) 163 return 1; 164 } 165 return 0; 166 } 167 168 /* allocate lnstat_file and open given file */ 169 static struct lnstat_file *alloc_and_open(const char *path, const char *file) 170 { 171 struct lnstat_file *lf; 172 173 /* allocate */ 174 lf = malloc(sizeof(*lf)); 175 if (!lf) { 176 fprintf(stderr, "out of memory\n"); 177 return NULL; 178 } 179 180 /* initialize */ 181 memset(lf, 0, sizeof(*lf)); 182 183 /* de->d_name is guaranteed to be <= NAME_MAX */ 184 strcpy(lf->basename, file); 185 strcpy(lf->path, path); 186 strcat(lf->path, "/"); 187 strcat(lf->path, lf->basename); 188 189 /* initialize to default */ 190 lf->interval.tv_sec = 1; 191 192 /* open */ 193 lf->fp = fopen(lf->path, "r"); 194 if (!lf->fp) { 195 perror(lf->path); 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 */ 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 closedir(dir); 264 return NULL; 265 } 266 267 /* fill in field structure */ 268 if (lnstat_scan_fields(lf) < 0) { 269 closedir(dir); 270 return NULL; 271 } 272 273 /* prepend to global list */ 274 lf->next = lnstat_files; 275 lnstat_files = lf; 276 } 277 closedir(dir); 278 279 return lnstat_files; 280 } 281 282 int lnstat_dump(FILE *outfd, struct lnstat_file *lnstat_files) 283 { 284 struct lnstat_file *lf; 285 286 for (lf = lnstat_files; lf; lf = lf->next) { 287 int i; 288 289 fprintf(outfd, "%s:\n", lf->path); 290 291 for (i = 0; i < lf->num_fields; i++) 292 fprintf(outfd, "\t%2u: %s\n", i+1, lf->fields[i].name); 293 294 } 295 return 0; 296 } 297 298 struct lnstat_field *lnstat_find_field(struct lnstat_file *lnstat_files, 299 const char *name) 300 { 301 struct lnstat_file *lf; 302 struct lnstat_field *ret = NULL; 303 const char *colon = strchr(name, ':'); 304 char *file; 305 const char *field; 306 307 if (colon) { 308 file = strndup(name, colon-name); 309 field = colon+1; 310 } else { 311 file = NULL; 312 field = name; 313 } 314 315 for (lf = lnstat_files; lf; lf = lf->next) { 316 int i; 317 318 if (file && strcmp(file, lf->basename)) 319 continue; 320 321 for (i = 0; i < lf->num_fields; i++) { 322 if (!strcmp(field, lf->fields[i].name)) { 323 ret = &lf->fields[i]; 324 goto out; 325 } 326 } 327 } 328 out: 329 free(file); 330 331 return ret; 332 } 333
