1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/content/canvas/src/CanvasUtils.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,175 @@
1.4 +/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
1.5 +/* This Source Code Form is subject to the terms of the Mozilla Public
1.6 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.7 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.8 +
1.9 +#ifndef _CANVASUTILS_H_
1.10 +#define _CANVASUTILS_H_
1.11 +
1.12 +#include "mozilla/CheckedInt.h"
1.13 +#include "mozilla/dom/ToJSValue.h"
1.14 +#include "jsapi.h"
1.15 +
1.16 +class nsIPrincipal;
1.17 +
1.18 +namespace mozilla {
1.19 +
1.20 +namespace gfx {
1.21 +class Matrix;
1.22 +}
1.23 +
1.24 +namespace dom {
1.25 +class HTMLCanvasElement;
1.26 +}
1.27 +
1.28 +namespace CanvasUtils {
1.29 +
1.30 +
1.31 +// Check that the rectangle [x,y,w,h] is a subrectangle of [0,0,realWidth,realHeight]
1.32 +
1.33 +inline bool CheckSaneSubrectSize(int32_t x, int32_t y, int32_t w, int32_t h,
1.34 + int32_t realWidth, int32_t realHeight) {
1.35 + CheckedInt32 checked_xmost = CheckedInt32(x) + w;
1.36 + CheckedInt32 checked_ymost = CheckedInt32(y) + h;
1.37 +
1.38 + return w >= 0 && h >= 0 && x >= 0 && y >= 0 &&
1.39 + checked_xmost.isValid() &&
1.40 + checked_xmost.value() <= realWidth &&
1.41 + checked_ymost.isValid() &&
1.42 + checked_ymost.value() <= realHeight;
1.43 +}
1.44 +
1.45 +// Flag aCanvasElement as write-only if drawing an image with aPrincipal
1.46 +// onto it would make it such.
1.47 +
1.48 +void DoDrawImageSecurityCheck(dom::HTMLCanvasElement *aCanvasElement,
1.49 + nsIPrincipal *aPrincipal,
1.50 + bool forceWriteOnly,
1.51 + bool CORSUsed);
1.52 +
1.53 +bool IsImageExtractionAllowed(nsIDocument *aDocument, JSContext *aCx);
1.54 +
1.55 +// Make a double out of |v|, treating undefined values as 0.0 (for
1.56 +// the sake of sparse arrays). Return true iff coercion
1.57 +// succeeded.
1.58 +bool CoerceDouble(JS::Value v, double* d);
1.59 +
1.60 + /* Float validation stuff */
1.61 +#define VALIDATE(_f) if (!NS_finite(_f)) return false
1.62 +
1.63 +inline bool FloatValidate (double f1) {
1.64 + VALIDATE(f1);
1.65 + return true;
1.66 +}
1.67 +
1.68 +inline bool FloatValidate (double f1, double f2) {
1.69 + VALIDATE(f1); VALIDATE(f2);
1.70 + return true;
1.71 +}
1.72 +
1.73 +inline bool FloatValidate (double f1, double f2, double f3) {
1.74 + VALIDATE(f1); VALIDATE(f2); VALIDATE(f3);
1.75 + return true;
1.76 +}
1.77 +
1.78 +inline bool FloatValidate (double f1, double f2, double f3, double f4) {
1.79 + VALIDATE(f1); VALIDATE(f2); VALIDATE(f3); VALIDATE(f4);
1.80 + return true;
1.81 +}
1.82 +
1.83 +inline bool FloatValidate (double f1, double f2, double f3, double f4, double f5) {
1.84 + VALIDATE(f1); VALIDATE(f2); VALIDATE(f3); VALIDATE(f4); VALIDATE(f5);
1.85 + return true;
1.86 +}
1.87 +
1.88 +inline bool FloatValidate (double f1, double f2, double f3, double f4, double f5, double f6) {
1.89 + VALIDATE(f1); VALIDATE(f2); VALIDATE(f3); VALIDATE(f4); VALIDATE(f5); VALIDATE(f6);
1.90 + return true;
1.91 +}
1.92 +
1.93 +#undef VALIDATE
1.94 +
1.95 +template<typename T>
1.96 +nsresult
1.97 +JSValToDashArray(JSContext* cx, const JS::Value& val,
1.98 + FallibleTArray<T>& dashArray);
1.99 +
1.100 +template<typename T>
1.101 +JS::Value
1.102 +DashArrayToJSVal(FallibleTArray<T>& dashArray,
1.103 + JSContext* cx, mozilla::ErrorResult& rv);
1.104 +
1.105 +template<typename T>
1.106 +nsresult
1.107 +JSValToDashArray(JSContext* cx, const JS::Value& patternArray,
1.108 + FallibleTArray<T>& dashes)
1.109 +{
1.110 + // The cap is pretty arbitrary. 16k should be enough for
1.111 + // anybody...
1.112 + static const uint32_t MAX_NUM_DASHES = 1 << 14;
1.113 +
1.114 + if (!JSVAL_IS_PRIMITIVE(patternArray)) {
1.115 + JS::Rooted<JSObject*> obj(cx, JSVAL_TO_OBJECT(patternArray));
1.116 + uint32_t length;
1.117 + if (!JS_GetArrayLength(cx, obj, &length)) {
1.118 + // Not an array-like thing
1.119 + return NS_ERROR_INVALID_ARG;
1.120 + } else if (length > MAX_NUM_DASHES) {
1.121 + // Too many dashes in the pattern
1.122 + return NS_ERROR_ILLEGAL_VALUE;
1.123 + }
1.124 +
1.125 + bool haveNonzeroElement = false;
1.126 + for (uint32_t i = 0; i < length; ++i) {
1.127 + JS::Rooted<JS::Value> elt(cx);
1.128 + double d;
1.129 + if (!JS_GetElement(cx, obj, i, &elt)) {
1.130 + return NS_ERROR_FAILURE;
1.131 + }
1.132 + if (!(CoerceDouble(elt, &d) &&
1.133 + FloatValidate(d) &&
1.134 + d >= 0.0)) {
1.135 + // Pattern elements must be finite "numbers" >= 0.
1.136 + return NS_ERROR_INVALID_ARG;
1.137 + } else if (d > 0.0) {
1.138 + haveNonzeroElement = true;
1.139 + }
1.140 + if (!dashes.AppendElement(d)) {
1.141 + return NS_ERROR_OUT_OF_MEMORY;
1.142 + }
1.143 + }
1.144 +
1.145 + if (dashes.Length() > 0 && !haveNonzeroElement) {
1.146 + // An all-zero pattern makes no sense.
1.147 + return NS_ERROR_ILLEGAL_VALUE;
1.148 + }
1.149 + } else if (!(JSVAL_IS_VOID(patternArray) || JSVAL_IS_NULL(patternArray))) {
1.150 + // undefined and null mean "reset to no dash". Any other
1.151 + // random garbage is a type error.
1.152 + return NS_ERROR_INVALID_ARG;
1.153 + }
1.154 +
1.155 + return NS_OK;
1.156 +}
1.157 +
1.158 +template<typename T>
1.159 +void
1.160 +DashArrayToJSVal(FallibleTArray<T>& dashes,
1.161 + JSContext* cx,
1.162 + JS::MutableHandle<JS::Value> retval,
1.163 + mozilla::ErrorResult& rv)
1.164 +{
1.165 + if (dashes.IsEmpty()) {
1.166 + retval.setNull();
1.167 + return;
1.168 + }
1.169 + JS::Rooted<JS::Value> val(cx);
1.170 + if (!mozilla::dom::ToJSValue(cx, dashes, retval)) {
1.171 + rv.Throw(NS_ERROR_OUT_OF_MEMORY);
1.172 + }
1.173 +}
1.174 +
1.175 +}
1.176 +}
1.177 +
1.178 +#endif /* _CANVASUTILS_H_ */
