src/rrd_first.c

   1 /*****************************************************************************
   2  * RRDtool 1.2.23  Copyright by Tobi Oetiker, 1997-2007
   3  *****************************************************************************
   4  * rrd_first Return
   5  *****************************************************************************
   6  * Initial version by Burton Strauss, ntopSupport.com - 3/2005
   7  *****************************************************************************/
   8
   9 #include "rrd_tool.h"
  10
  11
  12 time_t
  13 rrd_first(int argc, char **argv)
  14 {
  15     int target_rraindex=0;
  16     char *endptr;
  17     optind = 0; opterr = 0;  /* initialize getopt */
  18
  19     while (1){
  20         static struct option long_options[] =
  21         {
  22             {"rraindex", required_argument, 0, 129},
  23             {0,0,0,0}
  24         };
  25         int option_index = 0;
  26         int opt;
  27         opt = getopt_long(argc, argv, "", long_options, &option_index);
  28
  29         if(opt == EOF)
  30             break;
  31
  32         switch(opt) {
  33           case 129:
  34             target_rraindex=strtol(optarg,&endptr,0);
  35             if(target_rraindex < 0) {
  36                 rrd_set_error("invalid rraindex number");
  37                 return(-1);
  38             }
  39             break;
  40           default:
  41             rrd_set_error("usage rrdtool %s [--rraindex number] file.rrd", argv[0]);
  42             return(-1);
  43         }
  44     }
  45
  46     if(optind >= argc){
  47         rrd_set_error("not enough arguments");
  48         return -1;
  49     }
  50
  51     return(rrd_first_r(argv[optind], target_rraindex));
  52 }
  53
  54
  55 time_t
  56 rrd_first_r(const char *filename, const int rraindex)
  57 {
  58     off_t rra_start,
  59          timer;
  60     time_t then;
  61     rrd_t rrd;
  62     rrd_file_t *rrd_file;
  63
  64     rrd_file = rrd_open(filename,&rrd, RRD_READONLY);
  65     if (rrd_file == NULL) {
  66         rrd_set_error("could not open RRD");
  67         return(-1);
  68     }
  69
  70     if((rraindex < 0) || (rraindex >= (int)rrd.stat_head->rra_cnt)) {
  71         rrd_set_error("invalid rraindex number");
  72         rrd_free(&rrd);
  73         close(rrd_file->fd);
  74         return(-1);
  75     }
  76
  77     rra_start = rrd_file->header_len;
  78     rrd_seek(rrd_file,
  79           (rra_start +
  80            (rrd.rra_ptr[rraindex].cur_row+1) *
  81            rrd.stat_head->ds_cnt *
  82            sizeof(rrd_value_t)),
  83           SEEK_SET);
  84     timer = - (rrd.rra_def[rraindex].row_cnt-1);
  85     if (rrd.rra_ptr[rraindex].cur_row + 1 > rrd.rra_def[rraindex].row_cnt) {
  86       rrd_seek(rrd_file,rra_start,SEEK_SET);
  87     }
  88     then = (rrd.live_head->last_up -
  89             rrd.live_head->last_up %
  90             (rrd.rra_def[rraindex].pdp_cnt*rrd.stat_head->pdp_step)) +
  91            (timer *
  92             rrd.rra_def[rraindex].pdp_cnt*rrd.stat_head->pdp_step);
  93
  94     rrd_free(&rrd);
  95     close(rrd_file->fd);
  96     rrd_close(rrd_file);
  97     return(then);
  98 }
  99