src/rrd_resize.c

   1 /*****************************************************************************
   2  * RRDtool 1.2.23  Copyright by Tobi Oetiker, 1997-2007
   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 rrd_resize(
  12     int argc,
  13     char **argv)
  14 {
  15     char     *infilename, outfilename[11] = "resize.rrd";
  16     rrd_t     rrdold, rrdnew;
  17     rrd_value_t buffer;
  18     int       version;
  19     unsigned long l, rra;
  20     long      modify;
  21     unsigned long target_rra;
  22     int       grow = 0, shrink = 0;
  23     char     *endptr;
  24     rrd_file_t *rrd_file, *rrd_out_file;
  25
  26     infilename = argv[1];
  27     if (!strcmp(infilename, "resize.rrd")) {
  28         rrd_set_error("resize.rrd is a reserved name");
  29         return (-1);
  30     }
  31     if (argc != 5) {
  32         rrd_set_error("wrong number of parameters");
  33         return (-1);
  34     }
  35
  36     target_rra = strtol(argv[2], &endptr, 0);
  37
  38     if (!strcmp(argv[3], "GROW"))
  39         grow = 1;
  40     else if (!strcmp(argv[3], "SHRINK"))
  41         shrink = 1;
  42     else {
  43         rrd_set_error("I can only GROW or SHRINK");
  44         return (-1);
  45     }
  46
  47     modify = strtol(argv[4], &endptr, 0);
  48
  49     if ((modify < 1)) {
  50         rrd_set_error("Please grow or shrink with at least 1 row");
  51         return (-1);
  52     }
  53
  54     if (shrink)
  55         modify = -modify;
  56
  57
  58     rrd_file = rrd_open(infilename, &rrdold, RRD_READWRITE | RRD_COPY);
  59     if (rrd_file == NULL) {
  60         rrd_free(&rrdold);
  61         return (-1);
  62     }
  63     if (LockRRD(rrd_file->fd) != 0) {
  64         rrd_set_error("could not lock original RRD");
  65         rrd_free(&rrdold);
  66         rrd_close(rrd_file);
  67         return (-1);
  68     }
  69
  70     if (target_rra >= rrdold.stat_head->rra_cnt) {
  71         rrd_set_error("no such RRA in this RRD");
  72         rrd_free(&rrdold);
  73         rrd_close(rrd_file);
  74         return (-1);
  75     }
  76
  77     if (modify < 0) {
  78         if ((long) rrdold.rra_def[target_rra].row_cnt <= -modify) {
  79             rrd_set_error("This RRA is not that big");
  80             rrd_free(&rrdold);
  81             rrd_close(rrd_file);
  82             return (-1);
  83         }
  84     } else {
  85         /* the size of the new file */
  86         rrdnew.stat_head = rrd_file->file_len +
  87             (rrdold.stat_head->ds_cnt * sizeof(rrd_value_t) * modify);
  88     }
  89     rrd_out_file = rrd_open(outfilename, &rrdnew, RRD_READWRITE | RRD_CREAT);
  90     if (rrd_out_file == NULL) {
  91         rrd_set_error("Can't create '%s': %s", outfilename,
  92                       rrd_strerror(errno));
  93         rrd_free(&rrdnew);
  94         return (-1);
  95     }
  96     if (LockRRD(rrd_out_file->fd) != 0) {
  97         rrd_set_error("could not lock new RRD");
  98         rrd_free(&rrdold);
  99         rrd_close(rrd_file);
 100         rrd_close(rrd_out_file);
 101         return (-1);
 102     }
 103 /*XXX: do one write for those parts of header that are unchanged */
 104     rrdnew.stat_head = rrdold.stat_head;
 105     rrdnew.ds_def = rrdold.ds_def;
 106     rrdnew.rra_def = rrdold.rra_def;
 107     rrdnew.live_head = rrdold.live_head;
 108     rrdnew.pdp_prep = rrdold.pdp_prep;
 109     rrdnew.cdp_prep = rrdold.cdp_prep;
 110     rrdnew.rra_ptr = rrdold.rra_ptr;
 111
 112     version = atoi(rrdold.stat_head->version);
 113     switch (version) {
 114     case 3:
 115         break;
 116     case 1:
 117         rrdold.stat_head->version[3] = '3';
 118         break;
 119     default:
 120         rrd_set_error("Do not know how to handle RRD version %s",
 121                       rrdold.stat_head->version);
 122         rrd_close(rrd_file);
 123         rrd_free(&rrdold);
 124         return (-1);
 125         break;
 126     }
 127
 128 /* XXX: Error checking? */
 129     rrd_write(rrd_out_file, rrdnew.stat_head, sizeof(stat_head_t) * 1);
 130     rrd_write(rrd_out_file, rrdnew.ds_def,
 131               sizeof(ds_def_t) * rrdnew.stat_head->ds_cnt);
 132     rrd_write(rrd_out_file, rrdnew.rra_def,
 133               sizeof(rra_def_t) * rrdnew.stat_head->rra_cnt);
 134     rrd_write(rrd_out_file, rrdnew.live_head, sizeof(live_head_t) * 1);
 135     rrd_write(rrd_out_file, rrdnew.pdp_prep,
 136               sizeof(pdp_prep_t) * rrdnew.stat_head->ds_cnt);
 137     rrd_write(rrd_out_file, rrdnew.cdp_prep,
 138               sizeof(cdp_prep_t) * rrdnew.stat_head->ds_cnt *
 139               rrdnew.stat_head->rra_cnt);
 140     rrd_write(rrd_out_file, rrdnew.rra_ptr,
 141               sizeof(rra_ptr_t) * rrdnew.stat_head->rra_cnt);
 142
 143     /* Move the CDPs from the old to the new database.
 144      ** This can be made (much) faster but isn't worth the effort. Clarity
 145      ** is much more important.
 146      */
 147
 148     /* Move data in unmodified RRAs
 149      */
 150     l = 0;
 151     for (rra = 0; rra < target_rra; rra++) {
 152         l += rrdnew.stat_head->ds_cnt * rrdnew.rra_def[rra].row_cnt;
 153     }
 154     while (l > 0) {
 155         rrd_read(rrd_file, &buffer, sizeof(rrd_value_t) * 1);
 156         rrd_write(rrd_out_file, &buffer, sizeof(rrd_value_t) * 1);
 157         l--;
 158     }
 159     /* Move data in this RRA, either removing or adding some rows
 160      */
 161     if (modify > 0) {
 162         /* Adding extra rows; insert unknown values just after the
 163          ** current row number.
 164          */
 165         l = rrdnew.stat_head->ds_cnt * (rrdnew.rra_ptr[target_rra].cur_row +
 166                                         1);
 167         while (l > 0) {
 168             rrd_read(rrd_file, &buffer, sizeof(rrd_value_t) * 1);
 169             rrd_write(rrd_out_file, &buffer, sizeof(rrd_value_t) * 1);
 170             l--;
 171         }
 172         buffer = DNAN;
 173         l = rrdnew.stat_head->ds_cnt * modify;
 174         while (l > 0) {
 175             rrd_write(rrd_out_file, &buffer, sizeof(rrd_value_t) * 1);
 176             l--;
 177         }
 178     } else {
 179         /* Removing rows. Normally this would be just after the cursor
 180          ** however this may also mean that we wrap to the beginning of
 181          ** the array.
 182          */
 183         signed long int remove_end = 0;
 184
 185         remove_end =
 186             (rrdnew.rra_ptr[target_rra].cur_row -
 187              modify) % rrdnew.rra_def[target_rra].row_cnt;
 188         if (remove_end <=
 189             (signed long int) rrdnew.rra_ptr[target_rra].cur_row) {
 190             while (remove_end >= 0) {
 191                 rrd_seek(rrd_file,
 192                          sizeof(rrd_value_t) * rrdnew.stat_head->ds_cnt,
 193                          SEEK_CUR);
 194                 rrdnew.rra_ptr[target_rra].cur_row--;
 195                 rrdnew.rra_def[target_rra].row_cnt--;
 196                 remove_end--;
 197                 modify++;
 198             }
 199             remove_end = rrdnew.rra_def[target_rra].row_cnt - 1;
 200         }
 201         for (l = 0; l <= rrdnew.rra_ptr[target_rra].cur_row; l++) {
 202             unsigned int tmp;
 203
 204             for (tmp = 0; tmp < rrdnew.stat_head->ds_cnt; tmp++) {
 205                 rrd_read(rrd_file, &buffer, sizeof(rrd_value_t) * 1);
 206                 rrd_write(rrd_out_file, &buffer, sizeof(rrd_value_t) * 1);
 207             }
 208         }
 209         while (modify < 0) {
 210             rrd_seek(rrd_file, sizeof(rrd_value_t) * rrdnew.stat_head->ds_cnt,
 211                      SEEK_CUR);
 212             rrdnew.rra_def[target_rra].row_cnt--;
 213             modify++;
 214         }
 215     }
 216     /* Move the rest of the CDPs
 217      */
 218     while (1) {
 219         if (rrd_read(rrd_file, &buffer, sizeof(rrd_value_t) * 1) <= 0)
 220             break;
 221         rrd_write(rrd_out_file, &buffer, sizeof(rrd_value_t) * 1);
 222     }
 223     rrdnew.rra_def[target_rra].row_cnt += modify;
 224     rrd_seek(rrd_out_file,
 225              sizeof(stat_head_t) +
 226              sizeof(ds_def_t) * rrdnew.stat_head->ds_cnt, SEEK_SET);
 227     rrd_write(rrd_out_file, rrdnew.rra_def,
 228               sizeof(rra_def_t) * rrdnew.stat_head->rra_cnt);
 229     rrd_seek(rrd_out_file, sizeof(live_head_t), SEEK_CUR);
 230     rrd_seek(rrd_out_file, sizeof(pdp_prep_t) * rrdnew.stat_head->ds_cnt,
 231              SEEK_CUR);
 232     rrd_seek(rrd_out_file,
 233              sizeof(cdp_prep_t) * rrdnew.stat_head->ds_cnt *
 234              rrdnew.stat_head->rra_cnt, SEEK_CUR);
 235     rrd_write(rrd_out_file, rrdnew.rra_ptr,
 236               sizeof(rra_ptr_t) * rrdnew.stat_head->rra_cnt);
 237
 238     rrd_free(&rrdold);
 239     rrd_close(rrd_file);
 240
 241     rrd_free(&rrdnew);
 242     rrd_close(rrd_out_file);
 243
 244     return (0);
 245 }