michael@0: /* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #ifndef _CANVASUTILS_H_
michael@0: #define _CANVASUTILS_H_
michael@0: 
michael@0: #include "mozilla/CheckedInt.h"
michael@0: #include "mozilla/dom/ToJSValue.h"
michael@0: #include "jsapi.h"
michael@0: 
michael@0: class nsIPrincipal;
michael@0: 
michael@0: namespace mozilla {
michael@0: 
michael@0: namespace gfx {
michael@0: class Matrix;
michael@0: }
michael@0: 
michael@0: namespace dom {
michael@0: class HTMLCanvasElement;
michael@0: }
michael@0: 
michael@0: namespace CanvasUtils {
michael@0: 
michael@0: 
michael@0: // Check that the rectangle [x,y,w,h] is a subrectangle of [0,0,realWidth,realHeight]
michael@0: 
michael@0: inline bool CheckSaneSubrectSize(int32_t x, int32_t y, int32_t w, int32_t h,
michael@0:                             int32_t realWidth, int32_t realHeight) {
michael@0:     CheckedInt32 checked_xmost  = CheckedInt32(x) + w;
michael@0:     CheckedInt32 checked_ymost  = CheckedInt32(y) + h;
michael@0: 
michael@0:     return w >= 0 && h >= 0 && x >= 0 && y >= 0 &&
michael@0:         checked_xmost.isValid() &&
michael@0:         checked_xmost.value() <= realWidth &&
michael@0:         checked_ymost.isValid() &&
michael@0:         checked_ymost.value() <= realHeight;
michael@0: }
michael@0: 
michael@0: // Flag aCanvasElement as write-only if drawing an image with aPrincipal
michael@0: // onto it would make it such.
michael@0: 
michael@0: void DoDrawImageSecurityCheck(dom::HTMLCanvasElement *aCanvasElement,
michael@0:                               nsIPrincipal *aPrincipal,
michael@0:                               bool forceWriteOnly,
michael@0:                               bool CORSUsed);
michael@0: 
michael@0: bool IsImageExtractionAllowed(nsIDocument *aDocument, JSContext *aCx);
michael@0: 
michael@0: // Make a double out of |v|, treating undefined values as 0.0 (for
michael@0: // the sake of sparse arrays).  Return true iff coercion
michael@0: // succeeded.
michael@0: bool CoerceDouble(JS::Value v, double* d);
michael@0: 
michael@0:     /* Float validation stuff */
michael@0: #define VALIDATE(_f)  if (!NS_finite(_f)) return false
michael@0: 
michael@0: inline bool FloatValidate (double f1) {
michael@0:     VALIDATE(f1);
michael@0:     return true;
michael@0: }
michael@0: 
michael@0: inline bool FloatValidate (double f1, double f2) {
michael@0:     VALIDATE(f1); VALIDATE(f2);
michael@0:     return true;
michael@0: }
michael@0: 
michael@0: inline bool FloatValidate (double f1, double f2, double f3) {
michael@0:     VALIDATE(f1); VALIDATE(f2); VALIDATE(f3);
michael@0:     return true;
michael@0: }
michael@0: 
michael@0: inline bool FloatValidate (double f1, double f2, double f3, double f4) {
michael@0:     VALIDATE(f1); VALIDATE(f2); VALIDATE(f3); VALIDATE(f4);
michael@0:     return true;
michael@0: }
michael@0: 
michael@0: inline bool FloatValidate (double f1, double f2, double f3, double f4, double f5) {
michael@0:     VALIDATE(f1); VALIDATE(f2); VALIDATE(f3); VALIDATE(f4); VALIDATE(f5);
michael@0:     return true;
michael@0: }
michael@0: 
michael@0: inline bool FloatValidate (double f1, double f2, double f3, double f4, double f5, double f6) {
michael@0:     VALIDATE(f1); VALIDATE(f2); VALIDATE(f3); VALIDATE(f4); VALIDATE(f5); VALIDATE(f6);
michael@0:     return true;
michael@0: }
michael@0: 
michael@0: #undef VALIDATE
michael@0: 
michael@0: template<typename T>
michael@0: nsresult
michael@0: JSValToDashArray(JSContext* cx, const JS::Value& val,
michael@0:                  FallibleTArray<T>& dashArray);
michael@0: 
michael@0: template<typename T>
michael@0: JS::Value
michael@0: DashArrayToJSVal(FallibleTArray<T>& dashArray,
michael@0:                  JSContext* cx, mozilla::ErrorResult& rv);
michael@0: 
michael@0: template<typename T>
michael@0: nsresult
michael@0: JSValToDashArray(JSContext* cx, const JS::Value& patternArray,
michael@0:                  FallibleTArray<T>& dashes)
michael@0: {
michael@0:     // The cap is pretty arbitrary.  16k should be enough for
michael@0:     // anybody...
michael@0:     static const uint32_t MAX_NUM_DASHES = 1 << 14;
michael@0: 
michael@0:     if (!JSVAL_IS_PRIMITIVE(patternArray)) {
michael@0:         JS::Rooted<JSObject*> obj(cx, JSVAL_TO_OBJECT(patternArray));
michael@0:         uint32_t length;
michael@0:         if (!JS_GetArrayLength(cx, obj, &length)) {
michael@0:             // Not an array-like thing
michael@0:             return NS_ERROR_INVALID_ARG;
michael@0:         } else if (length > MAX_NUM_DASHES) {
michael@0:             // Too many dashes in the pattern
michael@0:             return NS_ERROR_ILLEGAL_VALUE;
michael@0:         }
michael@0: 
michael@0:         bool haveNonzeroElement = false;
michael@0:         for (uint32_t i = 0; i < length; ++i) {
michael@0:             JS::Rooted<JS::Value> elt(cx);
michael@0:             double d;
michael@0:             if (!JS_GetElement(cx, obj, i, &elt)) {
michael@0:                 return NS_ERROR_FAILURE;
michael@0:             }
michael@0:             if (!(CoerceDouble(elt, &d) &&
michael@0:                   FloatValidate(d) &&
michael@0:                   d >= 0.0)) {
michael@0:                 // Pattern elements must be finite "numbers" >= 0.
michael@0:                 return NS_ERROR_INVALID_ARG;
michael@0:             } else if (d > 0.0) {
michael@0:                 haveNonzeroElement = true;
michael@0:             }
michael@0:             if (!dashes.AppendElement(d)) {
michael@0:                 return NS_ERROR_OUT_OF_MEMORY;
michael@0:             }
michael@0:         }
michael@0: 
michael@0:         if (dashes.Length() > 0 && !haveNonzeroElement) {
michael@0:             // An all-zero pattern makes no sense.
michael@0:             return NS_ERROR_ILLEGAL_VALUE;
michael@0:         }
michael@0:     } else if (!(JSVAL_IS_VOID(patternArray) || JSVAL_IS_NULL(patternArray))) {
michael@0:         // undefined and null mean "reset to no dash".  Any other
michael@0:         // random garbage is a type error.
michael@0:         return NS_ERROR_INVALID_ARG;
michael@0:     }
michael@0: 
michael@0:     return NS_OK;
michael@0: }
michael@0: 
michael@0: template<typename T>
michael@0: void
michael@0: DashArrayToJSVal(FallibleTArray<T>& dashes,
michael@0:                  JSContext* cx,
michael@0:                  JS::MutableHandle<JS::Value> retval,
michael@0:                  mozilla::ErrorResult& rv)
michael@0: {
michael@0:     if (dashes.IsEmpty()) {
michael@0:         retval.setNull();
michael@0:         return;
michael@0:     }
michael@0:     JS::Rooted<JS::Value> val(cx);
michael@0:     if (!mozilla::dom::ToJSValue(cx, dashes, retval)) {
michael@0:         rv.Throw(NS_ERROR_OUT_OF_MEMORY);
michael@0:     }
michael@0: }
michael@0: 
michael@0: }
michael@0: }
michael@0: 
michael@0: #endif /* _CANVASUTILS_H_ */