MDL-79285 xhprof: Add support for optional "reducedata" parameter

This new parameter / property will decide if we want to reduce
the run data before processing it:
- By default it will be disabled in table mode.
- By default it will be enabled in graph mode.
- The defaults can be changed by adding reducedata=[0|1] in the URLs
- Once data reduction is enabled, it stays enabled while
  navigating within the xhprof reports.

lib/xhprof/xhprof_html/callgraph.php

@@ -90,6 +90,7 @@ if (!array_key_exists($type, $xhprof_legal_image_types)) {
 // Start moodle modification: use own XHProfRuns implementation.
 // $xhprof_runs_impl = new XHProfRuns_Default();
 $xhprof_runs_impl = new moodle_xhprofrun();
+$xhprof_runs_impl->set_reducedata(xhprof_get_bool_param('reducedata', 1)); // Reduce data by default.
 // End moodle modification.
 
 if (!empty($run)) {

lib/xhprof/xhprof_html/index.php

@@ -92,6 +92,12 @@ $vgbar = ' class="vgbar"';
 // Start moodle modification: use own XHProfRuns implementation.
 // $xhprof_runs_impl = new XHProfRuns_Default();
 $xhprof_runs_impl = new moodle_xhprofrun();
+$reducedata = xhprof_get_bool_param('reducedata', 0); // Don't reduce data by default.
+$xhprof_runs_impl->set_reducedata($reducedata);
+if ($reducedata) {
+    // We need to inject it, so we continue in "reduced data mode" all the time.
+    $params['reducedata'] = $reducedata;
+}
 // End moodle modification.
 
 displayXHProfReport($xhprof_runs_impl, $params, $source, $run, $wts,

lib/xhprof/xhprof_moodle.php

@@ -859,6 +859,9 @@ class moodle_xhprofrun implements iXHProfRuns {
     protected $totalmemory = 0;
     protected $timecreated = 0;
 
+    /** @var bool Decide if we want to reduce profiling data or no */
+    protected bool $reducedata = false;
+
     public function __construct() {
         $this->timecreated = time();
     }
@@ -889,6 +892,10 @@ class moodle_xhprofrun implements iXHProfRuns {
             return unserialize(base64_decode($rec->data));
         } else {
             $info = unserialize(gzuncompress(base64_decode($rec->data)));
+            if (!$this->reducedata) {
+                // We want to return the full data.
+                return $info;
+            }
 
             // We want to apply some transformations here, in order to reduce
             // the information for some complex (too many levels) cases.
@@ -967,6 +974,15 @@ class moodle_xhprofrun implements iXHProfRuns {
         $this->url = $url;
     }
 
+    /**
+     * Enable or disable reducing profiling data.
+     *
+     * @param bool $reducedata Decide if we want to reduce profiling data (true) or no (false).
+     */
+    public function set_reducedata(bool $reducedata): void {
+        $this->reducedata = $reducedata;
+    }
+
     // Private API starts here.
 
     protected function sum_calls($sum, $data) {