unix4lyfe git - darkstat-debian/blob - graph_db.c

   1 /* darkstat 3
   2  * copyright (c) 2006-2014 Emil Mikulic.
   3  *
   4  * graph_db.c: round robin database for graph data
   5  *
   6  * You may use, modify and redistribute this file under the terms of the
   7  * GNU General Public License version 2. (see COPYING.GPL)
   8  */
   9
  10 #include <sys/types.h>
  11
  12 #include "cap.h"
  13 #include "conv.h"
  14 #include "db.h"
  15 #include "acct.h"
  16 #include "err.h"
  17 #include "str.h"
  18 #include "html.h"
  19 #include "graph_db.h"
  20 #include "now.h"
  21 #include "opt.h"
  22
  23 #include <assert.h>
  24 #include <stdlib.h>
  25 #include <string.h> /* for memcpy() */
  26 #include <time.h>
  27
  28 #define GRAPH_WIDTH "320"
  29 #define GRAPH_HEIGHT "200"
  30
  31 struct graph {
  32    uint64_t *in, *out;
  33    unsigned int offset; /* i.e. seconds start at 0, days start at 1 */
  34    unsigned int pos, num_bars;
  35    const char *unit;
  36    unsigned int bar_secs; /* one bar represents <n> seconds */
  37 };
  38
  39 static struct graph
  40    graph_secs = {NULL, NULL, 0, 0, 60, "seconds", 1},
  41    graph_mins = {NULL, NULL, 0, 0, 60, "minutes", 60},
  42    graph_hrs  = {NULL, NULL, 0, 0, 24, "hours",   3600},
  43    graph_days = {NULL, NULL, 1, 0, 31, "days",    86400};
  44
  45 static struct graph *graph_db[] = {
  46    &graph_secs, &graph_mins, &graph_hrs, &graph_days
  47 };
  48
  49 static unsigned int graph_db_size = sizeof(graph_db)/sizeof(*graph_db);
  50 static time_t start_mono, start_real, last_real;
  51
  52 void graph_init(void) {
  53    unsigned int i;
  54    for (i=0; i<graph_db_size; i++) {
  55       graph_db[i]->in  = xmalloc(sizeof(uint64_t) * graph_db[i]->num_bars);
  56       graph_db[i]->out = xmalloc(sizeof(uint64_t) * graph_db[i]->num_bars);
  57    }
  58    start_mono = now_mono();
  59    start_real = now_real();
  60    last_real = 0;
  61    graph_reset();
  62 }
  63
  64 static void zero_graph(struct graph *g) {
  65    memset(g->in,  0, sizeof(uint64_t) * g->num_bars);
  66    memset(g->out, 0, sizeof(uint64_t) * g->num_bars);
  67 }
  68
  69 void graph_reset(void) {
  70    unsigned int i;
  71
  72    for (i=0; i<graph_db_size; i++)
  73       zero_graph(graph_db[i]);
  74    last_real = 0;
  75 }
  76
  77 void graph_free(void) {
  78    unsigned int i;
  79
  80    for (i=0; i<graph_db_size; i++) {
  81       free(graph_db[i]->in);
  82       free(graph_db[i]->out);
  83    }
  84 }
  85
  86 void graph_acct(uint64_t amount, enum graph_dir dir) {
  87    unsigned int i;
  88    for (i=0; i<graph_db_size; i++)
  89       if (dir == GRAPH_IN) {
  90          graph_db[i]->in[  graph_db[i]->pos ] += amount;
  91       } else {
  92          assert(dir == GRAPH_OUT);
  93          graph_db[i]->out[ graph_db[i]->pos ] += amount;
  94       }
  95 }
  96
  97 /* Advance a graph: advance the pos, zeroing out bars as we move. */
  98 static void advance(struct graph *g, const unsigned int pos) {
  99    if (g->pos == pos)
 100       return; /* didn't need to advance */
 101    do {
 102       g->pos = (g->pos + 1) % g->num_bars;
 103       g->in[g->pos] = g->out[g->pos] = 0;
 104    } while (g->pos != pos);
 105 }
 106
 107 /* Rotate a graph: rotate all bars so that the bar at the current pos is moved
 108  * to the newly given pos.
 109  */
 110 static void rotate(struct graph *g, const unsigned int pos) {
 111    uint64_t *tmp;
 112    unsigned int i, ofs;
 113    size_t size;
 114
 115    if (pos == g->pos)
 116       return; /* nothing to rotate */
 117
 118    size = sizeof(*tmp) * g->num_bars;
 119    tmp = xmalloc(size);
 120    ofs = g->num_bars + pos - g->pos;
 121
 122    for (i=0; i<g->num_bars; i++)
 123       tmp[ (i+ofs) % g->num_bars ] = g->in[i];
 124    memcpy(g->in, tmp, size);
 125
 126    for (i=0; i<g->num_bars; i++)
 127       tmp[ (i+ofs) % g->num_bars ] = g->out[i];
 128    memcpy(g->out, tmp, size);
 129
 130    free(tmp);
 131    assert(g->num_bars > 0);
 132    assert(pos == ( (g->pos + ofs) % g->num_bars ));
 133    g->pos = pos;
 134 }
 135
 136 static void graph_resync(const time_t new_real) {
 137    struct tm *tm;
 138    /*
 139     * If real time went backwards, we assume that the time adjustment should
 140     * only affect display.  i.e., if we have:
 141     *
 142     * second 15: 12  bytes
 143     * second 16: 345 bytes
 144     * second 17: <-- current pos
 145     *
 146     * and time goes backwards to second 8, we will shift the graph around to
 147     * get:
 148     *
 149     * second 6: 12  bytes
 150     * second 7: 345 bytes
 151     * second 8: <-- current pos
 152     *
 153     * We don't make any corrections for time being stepped forward,
 154     * it's treated as though there was no traffic during that time.
 155     *
 156     * We rely on graph advancement to happen at the correct real time to
 157     * account for, for example, bandwidth used per day.
 158     */
 159    assert(new_real < last_real);
 160
 161    tm = localtime(&new_real);
 162    if (tm->tm_sec == 60)
 163       tm->tm_sec = 59; /* mis-handle leap seconds */
 164
 165    rotate(&graph_secs, tm->tm_sec);
 166    rotate(&graph_mins, tm->tm_min);
 167    rotate(&graph_hrs, tm->tm_hour);
 168    rotate(&graph_days, tm->tm_mday - 1);
 169
 170    last_real = new_real;
 171 }
 172
 173 void graph_rotate(void) {
 174    time_t t, td;
 175    struct tm *tm;
 176    unsigned int i;
 177
 178    t = now_real();
 179    td = t - last_real;
 180
 181    if (last_real == 0) {
 182       verbosef("first rotate");
 183       last_real = t;
 184       tm = localtime(&t);
 185       graph_secs.pos = tm->tm_sec;
 186       graph_mins.pos = tm->tm_min;
 187       graph_hrs.pos = tm->tm_hour;
 188       graph_days.pos = tm->tm_mday - 1;
 189       return;
 190    }
 191
 192    if (t == last_real)
 193       return; /* time has not advanced a full second, don't rotate */
 194
 195    if (t < last_real) {
 196       verbosef("graph_db: realtime went backwards! "
 197                "(from %ld to %ld, offset is %ld)",
 198                last_real, t, td);
 199       graph_resync(t);
 200       return;
 201    }
 202
 203    /* else, normal rotation */
 204    last_real = t;
 205    tm = localtime(&t);
 206
 207    /* zero out graphs which have been completely rotated through */
 208    for (i=0; i<graph_db_size; i++)
 209       if (td >= (int)(graph_db[i]->num_bars * graph_db[i]->bar_secs))
 210          zero_graph(graph_db[i]);
 211
 212    /* advance the current position, zeroing up to it */
 213    advance(&graph_secs, tm->tm_sec);
 214    advance(&graph_mins, tm->tm_min);
 215    advance(&graph_hrs, tm->tm_hour);
 216    advance(&graph_days, tm->tm_mday - 1);
 217 }
 218
 219 /* ---------------------------------------------------------------------------
 220  * Database Import: Grab graphs from a file provided by the caller.
 221  *
 222  * This function will retrieve the data sans the header.  We expect the caller
 223  * to have validated the header of the segment, and left the file position at
 224  * the start of the data.
 225  */
 226 int graph_import(const int fd) {
 227    uint64_t last;
 228    unsigned int i, j;
 229
 230    if (!read64(fd, &last)) return 0;
 231    last_real = last;
 232
 233    for (i=0; i<graph_db_size; i++) {
 234       unsigned char num_bars, pos;
 235       unsigned int filepos = xtell(fd);
 236
 237       if (!read8(fd, &num_bars)) return 0;
 238       if (!read8(fd, &pos)) return 0;
 239
 240       verbosef("at file pos %u, importing graph with %u bars",
 241          filepos, (unsigned int)num_bars);
 242
 243       if (pos >= num_bars) {
 244          warn("pos is %u, should be < num_bars which is %u",
 245             (unsigned int)pos, (unsigned int)num_bars);
 246          return 0;
 247       }
 248
 249       if (graph_db[i]->num_bars != num_bars) {
 250          warn("num_bars is %u, expecting %u",
 251             (unsigned int)num_bars, graph_db[i]->num_bars);
 252          return 0;
 253       }
 254
 255       graph_db[i]->pos = pos;
 256       for (j=0; j<num_bars; j++) {
 257          if (!read64(fd, &(graph_db[i]->in[j]))) return 0;
 258          if (!read64(fd, &(graph_db[i]->out[j]))) return 0;
 259       }
 260    }
 261
 262    return 1;
 263 }
 264
 265 /* ---------------------------------------------------------------------------
 266  * Database Export: Dump hosts_db into a file provided by the caller.
 267  * The caller is responsible for writing out the header first.
 268  */
 269 int graph_export(const int fd) {
 270    unsigned int i, j;
 271
 272    if (!write64(fd, (uint64_t)last_real)) return 0;
 273    for (i=0; i<graph_db_size; i++) {
 274       if (!write8(fd, graph_db[i]->num_bars)) return 0;
 275       if (!write8(fd, graph_db[i]->pos)) return 0;
 276
 277       for (j=0; j<graph_db[i]->num_bars; j++) {
 278          if (!write64(fd, graph_db[i]->in[j])) return 0;
 279          if (!write64(fd, graph_db[i]->out[j])) return 0;
 280       }
 281    }
 282    return 1;
 283 }
 284
 285 /* ---------------------------------------------------------------------------
 286  * Web interface: front page!
 287  */
 288 struct str *html_front_page(void) {
 289    struct str *buf, *rf;
 290    unsigned int i;
 291    char start_when[100];
 292    time_t d_real, d_mono;
 293
 294    buf = str_make();
 295    html_open(buf, "Graphs", /*path_depth=*/0, /*want_graph_js=*/1);
 296
 297    d_mono = now_mono() - start_mono;
 298    d_real = now_real() - start_real;
 299    str_append(buf, "<p>\n");
 300    str_append(buf, "<b>Running for</b> <span id=\"rf\">");
 301    rf = length_of_time(d_mono);
 302    str_appendstr(buf, rf);
 303    str_free(rf);
 304    str_append(buf, "</span>");
 305    if (abs(d_real - d_mono) > 1)
 306       str_appendf(buf, " (real time is off by %qd sec)",
 307                   (qd)d_real - (qd)d_mono);
 308
 309    if (strftime(start_when, sizeof(start_when),
 310       "%Y-%m-%d %H:%M:%S %Z%z", localtime(&start_real)) != 0)
 311       str_appendf(buf, "<b>, since</b> %s", start_when);
 312
 313    str_appendf(buf,"<b>.</b><br>\n"
 314       "<b>Total</b> <span id=\"tb\">%'qu</span> <b>bytes, "
 315       "in</b> <span id=\"tp\">%'qu</span> <b>packets.</b> "
 316       "(<span id=\"pc\">%'u</span> <b>captured,</b> "
 317       "<span id=\"pd\">%'u</span> <b>dropped)</b><br>\n"
 318       "</p>\n",
 319       (qu)acct_total_bytes,
 320       (qu)acct_total_packets,
 321       cap_pkts_recv,
 322       cap_pkts_drop);
 323
 324    str_append(buf,
 325       "<div id=\"graphs\">\n"
 326       "Graphs require JavaScript.\n"
 327       "<script type=\"text/javascript\">\n"
 328       "//<![CDATA[\n"
 329       "var graph_width = " GRAPH_WIDTH ";\n"
 330       "var graph_height = " GRAPH_HEIGHT ";\n"
 331       "var bar_gap = 1;\n"
 332       "var graphs_uri = \"graphs.xml\";\n"
 333       "var graphs = [\n"
 334    );
 335
 336    for (i=0; i<graph_db_size; i++)
 337       str_appendf(buf,
 338          " { id:\"g%u\", "
 339             "name:\"%s\", "
 340             "title:\"last %u %s\", "
 341             "bar_secs:%u"
 342          " }%s\n",
 343          i, graph_db[i]->unit, graph_db[i]->num_bars, graph_db[i]->unit,
 344          graph_db[i]->bar_secs, (i < graph_db_size-1) ? "," : "");
 345       /* trailing comma breaks on IE, makes the array one element longer */
 346
 347    str_append(buf,
 348       "];\n"
 349       "window.onload = graphs_init;\n"
 350       "//]]>\n"
 351       "</script>\n"
 352       "</div>\n"
 353    );
 354
 355    html_close(buf);
 356    return (buf);
 357 }
 358
 359 /* ---------------------------------------------------------------------------
 360  * Web interface: graphs.xml
 361  */
 362 struct str *xml_graphs(void) {
 363    unsigned int i, j;
 364    struct str *buf = str_make(), *rf;
 365
 366    str_appendf(buf, "<graphs tp=\"%qu\" tb=\"%qu\" pc=\"%u\" pd=\"%u\" rf=\"",
 367       (qu)acct_total_packets,
 368       (qu)acct_total_bytes,
 369       cap_pkts_recv,
 370       cap_pkts_drop);
 371    rf = length_of_time(now_real() - start_real);
 372    str_appendstr(buf, rf);
 373    str_free(rf);
 374    str_append(buf, "\">\n");
 375
 376    for (i=0; i<graph_db_size; i++) {
 377       const struct graph *g = graph_db[i];
 378
 379       str_appendf(buf, "<%s>\n", g->unit);
 380       j = g->pos;
 381       do {
 382          j = (j + 1) % g->num_bars;
 383          /* <element pos="" in="" out=""/> */
 384          str_appendf(buf, "<e p=\"%u\" i=\"%qu\" o=\"%qu\"/>\n",
 385             g->offset + j,
 386             (qu)g->in[j],
 387             (qu)g->out[j]);
 388       } while (j != g->pos);
 389       str_appendf(buf, "</%s>\n", g->unit);
 390    }
 391    str_append(buf, "</graphs>\n");
 392    return (buf);
 393 }
 394
 395 /* vim:set ts=3 sw=3 tw=80 et: */