src/rrd_resize.c

   1 /*****************************************************************************
   2  * RRDtool 1.0.33  Copyright Tobias Oetiker, 1997 - 2000
   3  *****************************************************************************
   4  * rrd_resize.c Alters size of an RRA
   5  *****************************************************************************
   6  * Initial version by Alex van den Bogaerdt
   7  *****************************************************************************/
   8
   9 #include "rrd_tool.h"
  10
  11 int
  12 rrd_resize(int argc, char **argv)
  13 {
  14     char             *infilename,outfilename[11]="resize.rrd";
  15     FILE             *infile,*outfile;
  16     rrd_t             rrdold,rrdnew;
  17     rrd_value_t       buffer;
  18     unsigned long     l,rra;
  19     long              modify;
  20     unsigned long     target_rra;
  21     int               grow=0,shrink=0;
  22     char             *endptr;
  23
  24     infilename=argv[1];
  25     if (!strcmp(infilename,"resize.rrd")) {
  26         rrd_set_error("resize.rrd is a reserved name");
  27         return(-1);
  28     }
  29     if (argc!=5) {
  30         rrd_set_error("wrong number of parameters");
  31         return(-1);
  32     }
  33
  34     target_rra=strtol(argv[2],&endptr,0);
  35
  36     if (!strcmp(argv[3],"GROW")) grow=1;
  37     else if (!strcmp(argv[3],"SHRINK")) shrink=1;
  38     else {
  39         rrd_set_error("I can only GROW or SHRINK");
  40         return(-1);
  41     }
  42
  43     modify=strtol(argv[4],&endptr,0);
  44
  45     if ((modify<1)) {
  46         rrd_set_error("you must have at least one row in the RRA");
  47         return(-1);
  48     }
  49
  50     if (shrink) modify = -modify;
  51
  52
  53     if (rrd_open(infilename, &infile, &rrdold, RRD_READWRITE)==-1) {
  54         rrd_set_error("could not open RRD");
  55         return(-1);
  56     }
  57     if (LockRRD(infile) != 0) {
  58         rrd_set_error("could not lock original RRD");
  59         rrd_free(&rrdold);
  60         fclose(infile);
  61         return(-1);
  62     }
  63
  64     if (target_rra >= rrdold.stat_head->rra_cnt) {
  65         rrd_set_error("no such RRA in this RRD");
  66         rrd_free(&rrdold);
  67         fclose(infile);
  68         return(-1);
  69     }
  70     if ((rrdold.rra_def[target_rra].row_cnt+modify)<0) {
  71         rrd_set_error("This RRA is not that big");
  72         rrd_free(&rrdold);
  73         fclose(infile);
  74         return(-1);
  75     }
  76
  77     rrdnew.stat_head = rrdold.stat_head;
  78     rrdnew.ds_def    = rrdold.ds_def;
  79     rrdnew.rra_def   = rrdold.rra_def;
  80     rrdnew.live_head = rrdold.live_head;
  81     rrdnew.pdp_prep  = rrdold.pdp_prep;
  82     rrdnew.cdp_prep  = rrdold.cdp_prep;
  83     rrdnew.rra_ptr   = rrdold.rra_ptr;
  84
  85     if ((outfile=fopen(outfilename,"wb"))==NULL) {
  86         rrd_set_error("Can't create '%s'",outfilename);
  87         return(-1);
  88     }
  89     if (LockRRD(outfile) != 0) {
  90         rrd_set_error("could not lock new RRD");
  91         rrd_free(&rrdold);
  92         fclose(infile);
  93         fclose(outfile);
  94         return(-1);
  95     }
  96     fwrite(rrdnew.stat_head, sizeof(stat_head_t),1,outfile);
  97     fwrite(rrdnew.ds_def,sizeof(ds_def_t),rrdnew.stat_head->ds_cnt,outfile);
  98     fwrite(rrdnew.rra_def,sizeof(rra_def_t),rrdnew.stat_head->rra_cnt,outfile);
  99     fwrite(rrdnew.live_head,sizeof(live_head_t),1,outfile);
 100     fwrite(rrdnew.pdp_prep,sizeof(pdp_prep_t),rrdnew.stat_head->ds_cnt,outfile);
 101     fwrite(rrdnew.cdp_prep,sizeof(cdp_prep_t),rrdnew.stat_head->ds_cnt*rrdnew.stat_head->rra_cnt,outfile);
 102     fwrite(rrdnew.rra_ptr,sizeof(rra_ptr_t),rrdnew.stat_head->rra_cnt,outfile);
 103
 104     /* Move the CDPs from the old to the new database.
 105     ** This can be made (much) faster but isn't worth the efford. Clarity
 106     ** is much more important.
 107     */
 108
 109     /* Move data in unmodified RRAs
 110     */
 111     l=0;
 112     for (rra=0;rra<target_rra;rra++) {
 113         l+=rrdnew.stat_head->ds_cnt * rrdnew.rra_def[rra].row_cnt;
 114     }
 115     while (l>0) {
 116         fread(&buffer,sizeof(rrd_value_t),1,infile);
 117         fwrite(&buffer,sizeof(rrd_value_t),1,outfile);
 118         l--;
 119     }
 120     /* Move data in this RRA, either removing or adding some rows
 121     */
 122     if (modify>0) {
 123         /* Adding extra rows; insert unknown values just after the
 124         ** current row number.
 125         */
 126         l = rrdnew.stat_head->ds_cnt * (rrdnew.rra_ptr[target_rra].cur_row+1);
 127         while (l>0) {
 128             fread(&buffer,sizeof(rrd_value_t),1,infile);
 129             fwrite(&buffer,sizeof(rrd_value_t),1,outfile);
 130             l--;
 131         }
 132         buffer=DNAN;
 133         l=rrdnew.stat_head->ds_cnt * modify;
 134         while (l>0) {
 135             fwrite(&buffer,sizeof(rrd_value_t),1,outfile);
 136             l--;
 137         }
 138     } else {
 139         /* Removing rows. Normally this would be just after the cursor
 140         ** however this may also mean that we wrap to the beginning of
 141         ** the array.
 142         */
 143         signed long int remove_end=0;
 144
 145         remove_end=(rrdnew.rra_ptr[target_rra].cur_row-modify)%rrdnew.rra_def[target_rra].row_cnt;
 146         if (remove_end <= rrdnew.rra_ptr[target_rra].cur_row) {
 147             while (remove_end >= 0) {
 148                 fseek(infile,sizeof(rrd_value_t)*rrdnew.stat_head->ds_cnt,SEEK_CUR);
 149                 rrdnew.rra_ptr[target_rra].cur_row--;
 150                 rrdnew.rra_def[target_rra].row_cnt--;
 151                 remove_end--;
 152                 modify++;
 153             }
 154             remove_end=rrdnew.rra_def[target_rra].row_cnt-1;
 155         }
 156         for (l=0;l<=rrdnew.rra_ptr[target_rra].cur_row;l++) {
 157             unsigned int tmp;
 158             for (tmp=0;tmp<rrdnew.stat_head->ds_cnt;tmp++) {
 159                 fread(&buffer,sizeof(rrd_value_t),1,infile);
 160                 fwrite(&buffer,sizeof(rrd_value_t),1,outfile);
 161             }
 162         }
 163         while (modify<0) {
 164             fseek(infile,sizeof(rrd_value_t)*rrdnew.stat_head->ds_cnt,SEEK_CUR);
 165             rrdnew.rra_def[target_rra].row_cnt--;
 166             modify++;
 167         }
 168     }
 169     /* Move the rest of the CDPs
 170     */
 171     while (!(feof(infile))) {
 172         fread(&buffer,sizeof(rrd_value_t),1,infile);
 173         fwrite(&buffer,sizeof(rrd_value_t),1,outfile);
 174     }
 175     rrdnew.rra_def[target_rra].row_cnt += modify;
 176     fseek(outfile,sizeof(stat_head_t)+sizeof(ds_def_t)*rrdnew.stat_head->ds_cnt,SEEK_SET);
 177     fwrite(rrdnew.rra_def,sizeof(rra_def_t),rrdnew.stat_head->rra_cnt, outfile);
 178     fseek(outfile,sizeof(live_head_t),SEEK_CUR);
 179     fseek(outfile,sizeof(pdp_prep_t)*rrdnew.stat_head->ds_cnt,SEEK_CUR);
 180     fseek(outfile,sizeof(cdp_prep_t)*rrdnew.stat_head->ds_cnt*rrdnew.stat_head->rra_cnt,SEEK_CUR);
 181     fwrite(rrdnew.rra_ptr,sizeof(rra_ptr_t),rrdnew.stat_head->rra_cnt, outfile);
 182
 183     fclose(outfile);
 184     rrd_free(&rrdold);
 185     fclose(infile);
 186     return(0);
 187 }