From 99c1d9af689e5325f3cf535c4007b3aeb8325229 Mon Sep 17 00:00:00 2001
From: Minteck <contact@minteck.org>
Date: Tue, 10 Jan 2023 14:54:04 +0100
Subject: Update - This is an automated commit

---
 .../w3c-hr-time/lib/calculate-clock-offset.js      | 39 ++++++++++++++++++++++
 1 file changed, 39 insertions(+)
 create mode 100644 school/node_modules/w3c-hr-time/lib/calculate-clock-offset.js

(limited to 'school/node_modules/w3c-hr-time/lib/calculate-clock-offset.js')

diff --git a/school/node_modules/w3c-hr-time/lib/calculate-clock-offset.js b/school/node_modules/w3c-hr-time/lib/calculate-clock-offset.js
new file mode 100644
index 0000000..8659d30
--- /dev/null
+++ b/school/node_modules/w3c-hr-time/lib/calculate-clock-offset.js
@@ -0,0 +1,39 @@
+"use strict";
+
+// This files implements the calculation of the offset between the global monotonic clock and UNIX time. This value is
+// known as |t1| in the calculation of "time origin timestamp" in the spec. This value needs to be calculated once and
+// can be used in all subsequent Performance instances.
+//
+// However, if the clock is not fast enough, the export is undefined to signify that we should use Date.now() to get the
+// time origin timestamp with millisecond accuracy, per spec.
+
+const { getGlobalMonotonicClockMS } = require("./global-monotonic-clock");
+const clockIsAccurate = require("./clock-is-accurate");
+
+// This function assumes the clock is accurate.
+function calculateClockOffset() {
+  const start = Date.now();
+  let cur = start;
+  // Limit the iterations, just in case we're running in an environment where Date.now() has been mocked and is
+  // constant.
+  for (let i = 0; i < 1e6 && cur === start; i++) {
+    cur = Date.now();
+  }
+
+  // At this point |cur| "just" became equal to the next millisecond -- the unseen digits after |cur| are approximately
+  // all 0, and |cur| is the closest to the actual value of the UNIX time. Now, get the current global monotonic clock
+  // value and do the remaining calculations.
+
+  return cur - getGlobalMonotonicClockMS();
+}
+
+if (clockIsAccurate) {
+  // Warm up the function.
+  calculateClockOffset();
+  calculateClockOffset();
+  calculateClockOffset();
+
+  module.exports = calculateClockOffset;
+} else {
+  module.exports = undefined;
+}
-- 
cgit