When fetching data from 'past' an rra, rrd_fetch was seeking past the rrd

[rrdtool-all.git] / program / src / rrd_fetch.c

diff --git a/program/src/rrd_fetch.c b/program/src/rrd_fetch.c
index 1b85edb1c602080c256b7ab440afbffeee359ab7..9d4765c1f0ad82a5f0e42a18218dfbe8396c2c91 100644 (file)
--- a/program/src/rrd_fetch.c
+++ b/program/src/rrd_fetch.c
@@ -1,5 +1,5 @@
 /*****************************************************************************
- * RRDtool 1.2.23  Copyright by Tobi Oetiker, 1997-2007
+ * RRDtool 1.2.28  Copyright by Tobi Oetiker, 1997-2008
  *****************************************************************************
  * rrd_fetch.c  read date from an rrd to use for further processing
  *****************************************************************************
@@ -205,7 +205,6 @@ rrd_fetch_fn(
     rrd_t     rrd;
     rrd_value_t    *data_ptr;
     unsigned long  rows;
-    long  rrd_head_size;
 
 #ifdef DEBUG
 fprintf(stderr,"Entered rrd_fetch_fn() searching for the best match\n");
@@ -215,8 +214,6 @@ fprintf(stderr,"Looking for: start %10lu end %10lu step %5lu\n",
 
     if(rrd_open(filename,&in_file,&rrd, RRD_READONLY)==-1)
        return(-1);
-
-    rrd_head_size = ftell(in_file);
     
     /* when was the really last update of this file ? */
 
@@ -262,8 +259,7 @@ fprintf(stderr,"Considering: start %10lu end %10lu step %5lu ",
            tmp_step_diff = labs(*step - (rrd.stat_head->pdp_step
                                           * rrd.rra_def[i].pdp_cnt));
            /* best full match */
-           if(cal_end >= *end 
-              && cal_start <= *start){
+           if(cal_start <= *start){
                if (first_full || (tmp_step_diff < best_full_step_diff)){
                    first_full=0;
                    best_full_step_diff = tmp_step_diff;
@@ -282,8 +278,6 @@ fprintf(stderr,"full match, not best\n");
                tmp_match = full_match;
                if (cal_start>*start)
                    tmp_match -= (cal_start-*start);
-               if (cal_end<*end)
-                   tmp_match -= (*end-cal_end);                
                if (first_part ||
                     (best_match < tmp_match) ||
                     (best_match == tmp_match && 
@@ -367,31 +361,34 @@ fprintf(stderr,"partial match, not best\n");
 #endif
 
     /* fill the gap at the start if needs be */
-
-    if (start_offset <= 0)
-       rra_pointer = rrd.rra_ptr[chosen_rra].cur_row+1;
-    else 
-       rra_pointer = rrd.rra_ptr[chosen_rra].cur_row+1+start_offset;
+    if (*start <= rra_end_time && *end >= rra_start_time - *step){
+        
+        if (start_offset <= 0)
+            rra_pointer = rrd.rra_ptr[chosen_rra].cur_row+1;
+        else 
+            rra_pointer = rrd.rra_ptr[chosen_rra].cur_row+1+start_offset;
     
-    if(fseek(in_file,(rra_base 
+        if(fseek(in_file,(rra_base 
                   + (rra_pointer
                      * *ds_cnt
                      * sizeof(rrd_value_t))),SEEK_SET) != 0){
-       rrd_set_error("seek error in RRA");
-       for (i=0;(unsigned)i<*ds_cnt;i++)
-             free((*ds_namv)[i]);
-       free(*ds_namv);
-       rrd_free(&rrd);
-       free(*data);
-       *data = NULL;
-       fclose(in_file);
-       return(-1);
-
-    }
+            rrd_set_error("seek error in RRA");
+            for (i=0;(unsigned)i<*ds_cnt;i++)
+                free((*ds_namv)[i]);
+            free(*ds_namv);
+            rrd_free(&rrd);
+            free(*data);
+            *data = NULL;
+            fclose(in_file);
+            return(-1);
+
+        }
 #ifdef DEBUG
-    fprintf(stderr,"First Seek: rra_base %lu rra_pointer %lu\n",
-           rra_base, rra_pointer);
+        fprintf(stderr,"First Seek: rra_base %lu rra_pointer %lu\n",
+                rra_base, rra_pointer);
 #endif
+    }
+    
     /* step trough the array */
 
     for (i=start_offset;
@@ -456,16 +453,6 @@ fprintf(stderr,"partial match, not best\n");
                fclose(in_file);
                return(-1);
            }
-#ifdef HAVE_POSIX_FADVISE
-       /* don't pollute the buffer cache with data read from the file. We do this while reading to 
-          keep damage minimal */
-       if (0 != posix_fadvise(fileno(in_file), rrd_head_size, 0, POSIX_FADV_DONTNEED)) {
-           rrd_set_error("setting POSIX_FADV_DONTNEED on '%s': %s",filename, rrd_strerror(errno));
-           fclose(in_file);
-           return(-1);
-       } 
-#endif
-
 #ifdef DEBUG
            fprintf(stderr,"post fetch %li -- ",i);
            for(ii=0;ii<*ds_cnt;ii++)
@@ -480,14 +467,6 @@ fprintf(stderr,"partial match, not best\n");
        
     }
     rrd_free(&rrd);
-#ifdef HAVE_POSIX_FADVISE
-    /* and just to be sure we drop everything except the header at the end */
-    if (0 != posix_fadvise(fileno(in_file), rrd_head_size, 0, POSIX_FADV_DONTNEED)) {
-           rrd_set_error("setting POSIX_FADV_DONTNEED on '%s': %s",filename, rrd_strerror(errno));
-           fclose(in_file);
-           return(-1);
-    } 
-#endif     
     fclose(in_file);
     return(0);
 }