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 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 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 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 */ 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 } 139 140 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 */ 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 */ 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 */ 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 */ 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 } 277 278 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 } 293 294 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
