1 /*

     2  * Copyright (C) 2008, 2009 Google Inc. All rights reserved.

     3  *

     4  * Redistribution and use in source and binary forms, with or without

     5  * modification, are permitted provided that the following conditions are

     6  * met:

     7  *

     8  *     * Redistributions of source code must retain the above copyright

     9  * notice, this list of conditions and the following disclaimer.

    10  *     * Redistributions in binary form must reproduce the above

    11  * copyright notice, this list of conditions and the following disclaimer

    12  * in the documentation and/or other materials provided with the

    13  * distribution.

    14  *     * Neither the name of Google Inc. nor the names of its

    15  * contributors may be used to endorse or promote products derived from

    16  * this software without specific prior written permission.

    17  *

    18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS

    19  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT

    20  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR

    21  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT

    22  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,

    23  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT

    24  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,

    25  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY

    26  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

    27  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE

    28  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

    29  */

    30 

    31 #include "config.h"

    32 #include "V8Utilities.h"

    33 

    34 #include <v8.h>

    35 

    36 #include "Document.h"

    37 #include "Frame.h"

    38 #include "ScriptExecutionContext.h"

    39 #include "ScriptState.h"

    40 #include "V8Binding.h"

    41 #include "V8Proxy.h"

    42 #include "WorkerContext.h"

    43 #include "WorkerContextExecutionProxy.h"

    44 

    45 #include <wtf/Assertions.h>

    46 #include "Frame.h"

    47 

    48 namespace WebCore {

    49 

    50 // Use an array to hold dependents. It works like a ref-counted scheme.

    51 // A value can be added more than once to the DOM object.

    52 void createHiddenDependency(v8::Handle<v8::Object> object, v8::Local<v8::Value> value, int cacheIndex)

    53 {

    54     v8::Local<v8::Value> cache = object->GetInternalField(cacheIndex);

    55     if (cache->IsNull() || cache->IsUndefined()) {

    56         cache = v8::Array::New();

    57         object->SetInternalField(cacheIndex, cache);

    58     }

    59 

    60     v8::Local<v8::Array> cacheArray = v8::Local<v8::Array>::Cast(cache);

    61     cacheArray->Set(v8::Integer::New(cacheArray->Length()), value);

    62 }

    63 

    64 void removeHiddenDependency(v8::Handle<v8::Object> object, v8::Local<v8::Value> value, int cacheIndex)

    65 {

    66     v8::Local<v8::Value> cache = object->GetInternalField(cacheIndex);

    67     if (!cache->IsArray())

    68         return;

    69     v8::Local<v8::Array> cacheArray = v8::Local<v8::Array>::Cast(cache);

    70     for (int i = cacheArray->Length() - 1; i >= 0; --i) {

    71         v8::Local<v8::Value> cached = cacheArray->Get(v8::Integer::New(i));

    72         if (cached->StrictEquals(value)) {

    73             cacheArray->Delete(i);

    74             return;

    75         }

    76     }

    77 }

    78     

    79 void transferHiddenDependency(v8::Handle<v8::Object> object,

    80                               EventListener* oldValue, 

    81                               v8::Local<v8::Value> newValue, 

    82                               int cacheIndex)

    83 {

    84     if (oldValue) {

    85         V8AbstractEventListener* oldListener = V8AbstractEventListener::cast(oldValue);

    86         if (oldListener) {

    87             v8::Local<v8::Object> oldListenerObject = oldListener->getExistingListenerObject();

    88             if (!oldListenerObject.IsEmpty())

    89                 removeHiddenDependency(object, oldListenerObject, cacheIndex);

    90         }

    91     }

    92     if (!newValue->IsNull() && !newValue->IsUndefined())

    93         createHiddenDependency(object, newValue, cacheIndex);

    94 }

    95     

    96 

    97 bool processingUserGesture()

    98 {

    99     Frame* frame = V8Proxy::retrieveFrameForEnteredContext();

   100     return frame && frame->script()->processingUserGesture();

   101 }

   102 

   103 Frame* callingOrEnteredFrame()

   104 {

   105     Frame* frame = V8Proxy::retrieveFrameForCallingContext();

   106     if (!frame) {

   107         // Unfortunately, when processing script from a plug-in, we might not

   108         // have a calling context.  In those cases, we fall back to the

   109         // entered context for security checks.

   110         // FIXME: We need a better API for retrieving frames that abstracts

   111         //        away this concern.

   112         frame = V8Proxy::retrieveFrameForEnteredContext();

   113     }

   114     return frame;

   115 }

   116 

   117 bool shouldAllowNavigation(Frame* frame)

   118 {

   119     Frame* callingOrEntered = callingOrEnteredFrame();

   120     return callingOrEntered && callingOrEntered->loader()->shouldAllowNavigation(frame);

   121 }

   122 

   123 KURL completeURL(const String& relativeURL)

   124 {

   125     // For histoical reasons, we need to complete the URL using the dynamic frame.

   126     Frame* frame = V8Proxy::retrieveFrameForEnteredContext();

   127     if (!frame)

   128         return KURL();

   129     return frame->loader()->completeURL(relativeURL);

   130 }

   131 

   132 void navigateIfAllowed(Frame* frame, const KURL& url, bool lockHistory, bool lockBackForwardList)

   133 {

   134     Frame* callingOrEntered = callingOrEnteredFrame();

   135     if (!callingOrEntered)

   136         return;

   137     if (!protocolIsJavaScript(url) || ScriptController::isSafeScript(frame))

   138         frame->redirectScheduler()->scheduleLocationChange(url.string(), callingOrEntered->loader()->outgoingReferrer(), lockHistory, lockBackForwardList, processingUserGesture());

   139 }

   140 

   141 ScriptExecutionContext* getScriptExecutionContext()

   142 {

   143 #if ENABLE(WORKERS)

   144     if (WorkerScriptController* controller = WorkerScriptController::controllerForContext())

   145         return controller->workerContext();

   146 #endif

   147 

   148     if (Frame* frame = V8Proxy::retrieveFrameForCurrentContext())

   149         return frame->document()->scriptExecutionContext();

   150 

   151     return 0;

   152 }

   153 

   154 } // namespace WebCore