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

   1 /* darkstat 3
   2  * copyright (c) 2006-2011 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 long 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    graph_reset();
  61 }
  62
  63 static void zero_graph(struct graph *g) {
  64    memset(g->in,  0, sizeof(uint64_t) * g->num_bars);
  65    memset(g->out, 0, sizeof(uint64_t) * g->num_bars);
  66 }
  67
  68 void graph_reset(void) {
  69    unsigned int i;
  70
  71    for (i=0; i<graph_db_size; i++)
  72       zero_graph(graph_db[i]);
  73    last_real = 0;
  74 }
  75
  76 void graph_free(void) {
  77    unsigned int i;
  78
  79    for (i=0; i<graph_db_size; i++) {
  80       free(graph_db[i]->in);
  81       free(graph_db[i]->out);
  82    }
  83 }
  84
  85 void graph_acct(uint64_t amount, enum graph_dir dir) {
  86    unsigned int i;
  87    for (i=0; i<graph_db_size; i++)
  88       if (dir == GRAPH_IN) {
  89          graph_db[i]->in[  graph_db[i]->pos ] += amount;
  90       } else {
  91          assert(dir == GRAPH_OUT);
  92          graph_db[i]->out[ graph_db[i]->pos ] += amount;
  93       }
  94 }
  95
  96 /* Advance a graph: advance the pos, zeroing out bars as we move. */
  97 static void advance(struct graph *g, const unsigned int pos) {
  98    if (g->pos == pos)
  99       return; /* didn't need to advance */
 100    do {
 101       g->pos = (g->pos + 1) % g->num_bars;
 102       g->in[g->pos] = g->out[g->pos] = 0;
 103    } while (g->pos != pos);
 104 }
 105
 106 /* Rotate a graph: rotate all bars so that the bar at the current pos is moved
 107  * to the newly given pos.
 108  */
 109 static void rotate(struct graph *g, const unsigned int pos) {
 110    uint64_t *tmp;
 111    unsigned int i, ofs;
 112    size_t size;
 113
 114    if (pos == g->pos)
 115       return; /* nothing to rotate */
 116
 117    size = sizeof(*tmp) * g->num_bars;
 118    tmp = xmalloc(size);
 119    ofs = g->num_bars + pos - g->pos;
 120
 121    for (i=0; i<g->num_bars; i++)
 122       tmp[ (i+ofs) % g->num_bars ] = g->in[i];
 123    memcpy(g->in, tmp, size);
 124
 125    for (i=0; i<g->num_bars; i++)
 126       tmp[ (i+ofs) % g->num_bars ] = g->out[i];
 127    memcpy(g->out, tmp, size);
 128
 129    free(tmp);
 130    assert(pos == ( (g->pos + ofs) % g->num_bars ));
 131    g->pos = pos;
 132 }
 133
 134 static void graph_resync(const time_t new_real) {
 135    struct tm *tm;
 136    /*
 137     * If real time went backwards, we assume that the time adjustment should
 138     * only affect display.  i.e., if we have:
 139     *
 140     * second 15: 12  bytes
 141     * second 16: 345 bytes
 142     * second 17: <-- current pos
 143     *
 144     * and time goes backwards to second 8, we will shift the graph around to
 145     * get:
 146     *
 147     * second 6: 12  bytes
 148     * second 7: 345 bytes
 149     * second 8: <-- current pos
 150     *
 151     * We don't make any corrections for time being stepped forward,
 152     * it's treated as though there was no traffic during that time.
 153     *
 154     * We rely on graph advancement to happen at the correct real time to
 155     * account for, for example, bandwidth used per day.
 156     */
 157    assert(new_real < last_real);
 158
 159    tm = localtime(&new_real);
 160    if (tm->tm_sec == 60)
 161       tm->tm_sec = 59; /* mis-handle leap seconds */
 162
 163    rotate(&graph_secs, tm->tm_sec);
 164    rotate(&graph_mins, tm->tm_min);
 165    rotate(&graph_hrs, tm->tm_hour);
 166    rotate(&graph_days, tm->tm_mday - 1);
 167
 168    last_real = new_real;
 169 }
 170
 171 void graph_rotate(void) {
 172    long t, td;
 173    struct tm *tm;
 174    unsigned int i;
 175
 176    t = now_real();
 177    td = t - last_real;
 178
 179    if (last_real == 0) {
 180       verbosef("first rotate");
 181       last_real = t;
 182       tm = localtime(&t);
 183       graph_secs.pos = tm->tm_sec;
 184       graph_mins.pos = tm->tm_min;
 185       graph_hrs.pos = tm->tm_hour;
 186       graph_days.pos = tm->tm_mday - 1;
 187       return;
 188    }
 189
 190    if (t == last_real)
 191       return; /* time has not advanced a full second, don't rotate */
 192
 193    if (t < last_real) {
 194       verbosef("graph_db: realtime went backwards! "
 195                "(from %ld to %ld, offset is %ld)",
 196                last_real, t, td);
 197       graph_resync(t);
 198       return;
 199    }
 200
 201    /* else, normal rotation */
 202    last_real = t;
 203    tm = localtime(&t);
 204
 205    /* zero out graphs which have been completely rotated through */
 206    for (i=0; i<graph_db_size; i++)
 207       if (td >= (int)(graph_db[i]->num_bars * graph_db[i]->bar_secs))
 208          zero_graph(graph_db[i]);
 209
 210    /* advance the current position, zeroing up to it */
 211    advance(&graph_secs, tm->tm_sec);
 212    advance(&graph_mins, tm->tm_min);
 213    advance(&graph_hrs, tm->tm_hour);
 214    advance(&graph_days, tm->tm_mday - 1);
 215 }
 216
 217 /* ---------------------------------------------------------------------------
 218  * Database Import: Grab graphs from a file provided by the caller.
 219  *
 220  * This function will retrieve the data sans the header.  We expect the caller
 221  * to have validated the header of the segment, and left the file position at
 222  * the start of the data.
 223  */
 224 int graph_import(const int fd) {
 225    uint64_t last;
 226    unsigned int i, j;
 227
 228    if (!read64(fd, &last)) return 0;
 229    last_real = last;
 230
 231    for (i=0; i<graph_db_size; i++) {
 232       unsigned char num_bars, pos;
 233       unsigned int filepos = xtell(fd);
 234
 235       if (!read8(fd, &num_bars)) return 0;
 236       if (!read8(fd, &pos)) return 0;
 237
 238       verbosef("at file pos %u, importing graph with %u bars",
 239          filepos, (unsigned int)num_bars);
 240
 241       if (pos >= num_bars) {
 242          warn("pos is %u, should be < num_bars which is %u",
 243             (unsigned int)pos, (unsigned int)num_bars);
 244          return 0;
 245       }
 246
 247       if (graph_db[i]->num_bars != num_bars) {
 248          warn("num_bars is %u, expecting %u",
 249             (unsigned int)num_bars, graph_db[i]->num_bars);
 250          return 0;
 251       }
 252
 253       graph_db[i]->pos = pos;
 254       for (j=0; j<num_bars; j++) {
 255          if (!read64(fd, &(graph_db[i]->in[j]))) return 0;
 256          if (!read64(fd, &(graph_db[i]->out[j]))) return 0;
 257       }
 258    }
 259
 260    return 1;
 261 }
 262
 263 /* ---------------------------------------------------------------------------
 264  * Database Export: Dump hosts_db into a file provided by the caller.
 265  * The caller is responsible for writing out the header first.
 266  */
 267 int graph_export(const int fd) {
 268    unsigned int i, j;
 269
 270    if (!write64(fd, (uint64_t)last_real)) return 0;
 271    for (i=0; i<graph_db_size; i++) {
 272       if (!write8(fd, graph_db[i]->num_bars)) return 0;
 273       if (!write8(fd, graph_db[i]->pos)) return 0;
 274
 275       for (j=0; j<graph_db[i]->num_bars; j++) {
 276          if (!write64(fd, graph_db[i]->in[j])) return 0;
 277          if (!write64(fd, graph_db[i]->out[j])) return 0;
 278       }
 279    }
 280    return 1;
 281 }
 282
 283 /* ---------------------------------------------------------------------------
 284  * Web interface: front page!
 285  */
 286 struct str *html_front_page(void) {
 287    struct str *buf, *rf;
 288    unsigned int i;
 289    char start_when[100];
 290    long d_real, d_mono;
 291
 292    buf = str_make();
 293    html_open(buf, "Graphs", /*path_depth=*/0, /*want_graph_js=*/1);
 294
 295    d_mono = now_mono() - start_mono;
 296    d_real = now_real() - start_real;
 297    str_append(buf, "<p>\n");
 298    str_append(buf, "<b>Running for</b> <span id=\"rf\">");
 299    rf = length_of_time(d_mono);
 300    str_appendstr(buf, rf);
 301    str_free(rf);
 302    str_append(buf, "</span>");
 303    if (abs(d_real - d_mono) > 1)
 304       str_appendf(buf, " (real time is off by %qd sec)",
 305                   (int64_t)d_real - (int64_t)d_mono);
 306
 307    if (strftime(start_when, sizeof(start_when),
 308       "%Y-%m-%d %H:%M:%S %Z%z", localtime(&start_real)) != 0)
 309       str_appendf(buf, "<b>, since</b> %s", start_when);
 310
 311    str_appendf(buf,"<b>.</b><br>\n"
 312       "<b>Total</b> <span id=\"tb\">%'qu</span> <b>bytes, "
 313       "in</b> <span id=\"tp\">%'qu</span> <b>packets.</b> "
 314       "(<span id=\"pc\">%'u</span> <b>captured,</b> "
 315       "<span id=\"pd\">%'u</span> <b>dropped)</b><br>\n"
 316       "</p>\n",
 317       acct_total_bytes,
 318       acct_total_packets,
 319       cap_pkts_recv, cap_pkts_drop);
 320
 321    str_append(buf,
 322       "<div id=\"graphs\">\n"
 323       "Graphs require JavaScript.\n"
 324       "<script type=\"text/javascript\">\n"
 325       "//<![CDATA[\n"
 326       "var graph_width = " GRAPH_WIDTH ";\n"
 327       "var graph_height = " GRAPH_HEIGHT ";\n"
 328       "var bar_gap = 1;\n"
 329       "var graphs_uri = \"graphs.xml\";\n"
 330       "var graphs = [\n"
 331    );
 332
 333    for (i=0; i<graph_db_size; i++)
 334       str_appendf(buf,
 335          " { id:\"g%u\", "
 336             "name:\"%s\", "
 337             "title:\"last %u %s\", "
 338             "bar_secs:%u"
 339          " }%s\n",
 340          i, graph_db[i]->unit, graph_db[i]->num_bars, graph_db[i]->unit,
 341          graph_db[i]->bar_secs, (i < graph_db_size-1) ? "," : "");
 342       /* trailing comma breaks on IE, makes the array one element longer */
 343
 344    str_append(buf,
 345       "];\n"
 346       "window.onload = graphs_init;\n"
 347       "//]]>\n"
 348       "</script>\n"
 349       "</div>\n"
 350    );
 351
 352    html_close(buf);
 353    return (buf);
 354 }
 355
 356 /* ---------------------------------------------------------------------------
 357  * Web interface: graphs.xml
 358  */
 359 struct str *xml_graphs(void) {
 360    unsigned int i, j;
 361    struct str *buf = str_make(), *rf;
 362
 363    str_appendf(buf, "<graphs tp=\"%qu\" tb=\"%qu\" pc=\"%u\" pd=\"%u\" rf=\"",
 364       acct_total_packets, acct_total_bytes, cap_pkts_recv, cap_pkts_drop);
 365    rf = length_of_time(now_real() - start_real);
 366    str_appendstr(buf, rf);
 367    str_free(rf);
 368    str_append(buf, "\">\n");
 369
 370    for (i=0; i<graph_db_size; i++) {
 371       const struct graph *g = graph_db[i];
 372
 373       str_appendf(buf, "<%s>\n", g->unit);
 374       j = g->pos;
 375       do {
 376          j = (j + 1) % g->num_bars;
 377          /* <element pos="" in="" out=""/> */
 378          str_appendf(buf, "<e p=\"%u\" i=\"%qu\" o=\"%qu\"/>\n",
 379             g->offset + j, g->in[j], g->out[j]);
 380       } while (j != g->pos);
 381       str_appendf(buf, "</%s>\n", g->unit);
 382    }
 383    str_append(buf, "</graphs>\n");
 384    return (buf);
 385 }
 386
 387 /* vim:set ts=3 sw=3 tw=80 et: */