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+/** \file
+ * \brief Main file handling wrappers
+ *
+ * \author Copyright (C) 2019 Libor Polcak
+ *
+ * \license SPDX-License-Identifier: GPL-3.0-or-later
+ */
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program. If not, see <https://www.gnu.org/licenses/>.
+//
+
+/**
+ * \defgroup wrappers JavaScript Shield
+ *
+ * \brief Wrappers are small pieces of code that modifies the original functionalty of a function,
+ * or property defined by standards.
+ *
+ * $(PROJECT_NAME) defines wrappers to modify the behaviour of the JavaScript environment. The
+ * purpose of the most of the wrappers can be divided into several categories:
+ *
+ * * Block APIs: some APIs are not generally needed and can be blocked for most of the pages.
+ * * Precision reduction: The returned value is too precise which might result into attacks on the
+ * browser or can be used to fingerprint users.
+ * * Hide information: Some APIs provide information that is not generally needed and can be hidden
+ * from most of the pages.
+ * * Provide fake information: We provide fake information mostly to confuse fingerprinters.
+ */
+
+/**
+ * The object carrying all the wrappers
+ */
+var build_wrapping_code = {};
+
+/**
+ * Adds a list of wrapping objects to the build_wrapping_code.
+ *
+ * This function is called from each wrapper in its file.
+ */
+function add_wrappers(wrappers) {
+ for (wrapper of wrappers) {
+ build_wrapping_code[wrapper.parent_object + "." + wrapper.parent_object_property] = wrapper;
+ }
+}
+
+/**
+ * Function to be used by wrapped code used for rounding
+ */
+var rounding_function = `function rounding_function(numberToRound, precision) {
+ return numberToRound - (numberToRound % Math.pow(10, Math.max(3 - precision)));
+}`;
+
+/**
+ * Function to be used by wrapped code for adding randomized noise
+ */
+var noise_function = `let lastValue = 0;
+ function noise_function(numberToChange, precision) {
+ const noise = Math.floor(Math.random() * Math.pow(10, 3 - precision));
+ const arr = (numberToChange + '').split('.');
+ const number = parseInt(arr[0]);
+ const decimal = parseInt(arr[1]);
+ var value = number - (number % noise) + parseFloat('0.' + (decimal - (decimal % noise)));
+ if (lastValue < value) {
+ lastValue = value;
+ }
+ return lastValue;
+}`;