diff options
Diffstat (limited to 'src/lib')
| -rw-r--r-- | src/lib/rrdFile.js | 147 |
1 files changed, 99 insertions, 48 deletions
diff --git a/src/lib/rrdFile.js b/src/lib/rrdFile.js index 0d8182f..d86e065 100644 --- a/src/lib/rrdFile.js +++ b/src/lib/rrdFile.js @@ -33,7 +33,6 @@ * The data provided to this module require an object of a class
* that implements the following methods:
* getByteAt(idx) - Return a 8 bit unsigned integer at offset idx
- * getShortAt(idx) - Return a 16 bit unsigned integer at offset idx
* getLongAt(idx) - Return a 32 bit unsigned integer at offset idx
* getDoubleAt(idx) - Return a double float at offset idx
* getFastDoubleAt(idx) - Similar to getDoubleAt but with less precision
@@ -59,7 +58,7 @@ InvalidRRD.prototype.toString = function() { // ============================================================
-// RRD DS handling class
+// RRD DS Info class
function RRDDS(rrd_data,rrd_data_idx) {
this.rrd_data=rrd_data;
this.rrd_data_idx=rrd_data_idx;
@@ -80,60 +79,102 @@ RRDDS.prototype.getMax = function() { // ============================================================
+// RRD RRA Info class
+function RRDRRAInfo(rrd_data,rra_def_idx,
+ rrd_align,row_cnt,pdp_step) {
+ this.rrd_data=rrd_data;
+ this.rra_def_idx=rra_def_idx;
+ this.rrd_align=rrd_align;
+ this.row_cnt=row_cnt;
+ this.pdp_step=pdp_step;
+}
+
+// Get number of rows
+RRDRRAInfo.prototype.getNrRows = function() {
+ return this.row_cnt;
+}
+
+// Get number of slots used for consolidation
+// Mostly for internal use
+RRDRRAInfo.prototype.getPdpPerRow = function() {
+ if (this.rrd_align==32)
+ return this.rrd_data.getLongAt(this.rra_def_idx+24,20);
+ else
+ return this.rrd_data.getLongAt(this.rra_def_idx+32,20);
+}
+
+// Get step per row (expressed in seconds)
+RRDRRAInfo.prototype.getStepPerRow = function() {
+ return this.pdp_step*this.getPdpPerRow();
+}
+
+// Get consolidation function name
+RRDRRAInfo.prototype.getCFName = function() {
+ return this.rrd_data.getCStringAt(this.rra_def_idx,20);
+}
+
+
+// ============================================================
// RRD RRA handling class
-function RRDRRA(rrd_data,rrd_align,
- rra_def_idx,rra_ptr_idx,
- header_size,row_cnt,prev_row_cnts,ds_cnt,pdp_step) {
+function RRDRRA(rrd_data,rra_ptr_idx,
+ rra_info,
+ header_size,prev_row_cnts,ds_cnt) {
+ this.rrd_data=rrd_data;
+ this.rra_info=rra_info;
+ this.row_cnt=rra_info.row_cnt;
+ this.ds_cnt=ds_cnt;
+
var row_size=ds_cnt*8;
- var base_rrd_db_idx=header_size+prev_row_cnts*row_size;
+
+ this.base_rrd_db_idx=header_size+prev_row_cnts*row_size;
+
// get imediately, since it will be needed often
var cur_row=rrd_data.getLongAt(rra_ptr_idx);
- var calc_idx = function(row_idx,ds_idx) {
- if ((row_idx>=0) && (row_idx<row_cnt)) {
+ // calculate idx relative to base_rrd_db_idx
+ // mostly used internally
+ this.calc_idx = function(row_idx,ds_idx) {
+ if ((row_idx>=0) && (row_idx<this.row_cnt)) {
if ((ds_idx>=0) && (ds_idx<ds_cnt)){
// it is round robin, starting from cur_row+1
var real_row_idx=row_idx+cur_row+1;
- if (real_row_idx>=row_cnt) real_row_idx-=row_cnt;
+ if (real_row_idx>=this.row_cnt) real_row_idx-=this.row_cnt;
return row_size*real_row_idx+ds_idx*8;
} else {
throw RangeError("DS idx ("+ row_idx +") out of range [0-" + ds_cnt +").");
}
} else {
- throw RangeError("Row idx ("+ row_idx +") out of range [0-" + row_cnt +").");
+ throw RangeError("Row idx ("+ row_idx +") out of range [0-" + this.row_cnt +").");
}
}
+}
+
+// Get number of rows/columns
+RRDRRA.prototype.getNrRows = function() {
+ return this.row_cnt;
+}
+RRDRRA.prototype.getNrDSs = function() {
+ return this.ds_cnt;
+}
- // ----------------------------
- // Start of public methods
+// Get step per row (expressed in seconds)
+RRDRRA.prototype.getStepPerRow = function() {
+ return this.rra_info.getStepPerRow();
+}
- this.getName = function() {
- return rrd_data.getCStringAt(rra_def_idx,20);
- }
- this.getPdpPerRow = function() {
- if (rrd_align==32)
- return rrd_data.getLongAt(rra_def_idx+24,20);
- else
- return rrd_data.getLongAt(rra_def_idx+32,20);
- }
- this.getSecsPerRow = function() {
- return pdp_step*this.getPdpPerRow();
- }
+// Get consolidation function name
+RRDRRA.prototype.getCFName = function() {
+ return this.rra_info.getCFName();
+}
- this.getNrRows = function() {
- return row_cnt;
- }
- this.getNrDSs = function() {
- return ds_cnt;
- }
+RRDRRA.prototype.getEl = function(row_idx,ds_idx) {
+ return this.rrd_data.getDoubleAt(this.base_rrd_db_idx+this.calc_idx(row_idx,ds_idx));
+}
- this.getEl = function(row_idx,ds_idx) {
- return rrd_data.getDoubleAt(base_rrd_db_idx+calc_idx(row_idx,ds_idx));
- }
- // Extracts only 4 bytes out of 8 in double, loosing in precision (20 bit mantissa)
- this.getElFast = function(row_idx,ds_idx) {
- return rrd_data.getFastDoubleAt(base_rrd_db_idx+calc_idx(row_idx,ds_idx));
- }
+// Low precision version of getEl
+// Uses getFastDoubleAt
+RRDRRA.prototype.getElFast = function(row_idx,ds_idx) {
+ return this.rrd_data.getFastDoubleAt(this.base_rrd_db_idx+this.calc_idx(row_idx,ds_idx));
}
// ============================================================
@@ -261,6 +302,19 @@ RRDHeader.prototype.getDS = function(idx) { }
}
+RRDHeader.prototype.getNrRRAs = function() {
+ return this.rra_cnt;
+}
+RRDHeader.prototype.getRRAInfo = function(idx) {
+ if ((idx>=0) && (idx<this.rra_cnt)) {
+ return new RRDRRAInfo(this.rrd_data,
+ this.rra_def_idx+idx*this.rra_def_el_size,
+ this.rrd_align,this.rra_def_row_cnts[idx],this.pdp_step);
+ } else {
+ throw RangeError("RRA idx ("+ idx +") out of range [0-" + this.rra_cnt +").");
+ }
+}
+
// ============================================================
// RRDFile class
// Given a BinaryFile, gives access to the RRD archive fields
@@ -291,20 +345,17 @@ function RRDFile(bf) { }
this.getNrRRAs = function() {
- return this.rrd_header.rra_cnt;
+ return this.rrd_header.getNrRRAs(idx);
}
this.getRRA = function(idx) {
- if ((idx>=0) && (idx<this.rrd_header.rra_cnt)) {
- return new RRDRRA(rrd_data,this.rrd_header.rrd_align,
- this.rrd_header.rra_def_idx+idx*this.rrd_header.rra_def_el_size,
- this.rrd_header.rra_ptr_idx+idx*this.rrd_header.rra_ptr_el_size,
- this.rrd_header.header_size,
- this.rrd_header.rra_def_row_cnts[idx],this.rrd_header.rra_def_row_cnt_sums[idx],
- this.rrd_header.ds_cnt,this.rrd_header.pdp_step);
- } else {
- throw RangeError("RRA idx ("+ idx +") out of range [0-" + this.rrd_header.rra_cnt +").");
- }
+ rra_info=this.rrd_header.getRRAInfo(idx);
+ return new RRDRRA(rrd_data,
+ this.rrd_header.rra_ptr_idx+idx*this.rrd_header.rra_ptr_el_size,
+ rra_info,
+ this.rrd_header.header_size,
+ this.rrd_header.rra_def_row_cnt_sums[idx],
+ this.rrd_header.ds_cnt);
}
}
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