mirror of
https://github.com/kkapsner/CanvasBlocker
synced 2024-07-05 00:29:17 +02:00
46 lines
1.3 KiB
JavaScript
46 lines
1.3 KiB
JavaScript
var getContext = unsafeWindow.HTMLCanvasElement.prototype.getContext;
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var askFunctionName = Math.random().toString(16);
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function block(){
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// consoe.log("block");
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delete unsafeWindow.HTMLCanvasElement.prototype[askFunctionName];
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unsafeWindow.HTMLCanvasElement.prototype.getContext = null;
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}
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function ask(){
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// console.log("ask");
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Object.defineProperty(
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unsafeWindow.HTMLCanvasElement.prototype,
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askFunctionName,
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{
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value: getContext,
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enumerabe: false
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}
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);
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unsafeWindow.HTMLCanvasElement.prototype.getContext = new unsafeWindow.Function(function(){
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var oldBorder = this.style.border;
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this.style.border = "2px dashed red";
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var confirmText =
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this.parentNode?
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"Do you want to allow the red bordered <canvas>?":
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"Do you want to allow an invisibe <canvas>?";
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var allow = confirm(confirmText);
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this.style.border = oldBorder;
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if (allow){
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return this["askFunctionName"].apply(this, arguments);
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}
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else {
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return null;
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}
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}.toString().replace(/^function\s*\(\)\s*\{|\}\s*$/g, "").replace("askFunctionName", askFunctionName));
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}
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function unblock(){
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// console.log("unblock");
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unsafeWindow.HTMLCanvasElement.prototype.getContext = getContext;
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}
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ask();
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self.port.on("block", block);
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self.port.on("ask", ask);
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self.port.on("unblock", unblock);
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self.port.on("detach", unblock); |