Webkit Download files webkit 文件下载流程分析

1. WebView.loadUrl

......

2.bool MainResourceLoader::loadNow(ResourceRequest& r)

3.m_handle = ResourceHandle::create(m_frame->loader()->networkingContext(), r, this, false, true);

....

network

.....

4.void MainResourceLoader::didReceiveResponse(const ResourceResponse& r).(this will be called when the first package comes)

5.MainResourceLoader.cpp    frameLoader()->policyChecker()->checkContentPolicy(m_response.mimeType(), callContinueAfterContentPolicy, this);

//first checkContentpolicy and then call the func pointer that passed in.

6.void MainResourceLoader::callContinueAfterContentPolicy(void* argument, PolicyAction policy)

//policy already nailed down.

7.void MainResourceLoader::continueAfterContentPolicy(PolicyAction policy)

8.void MainResourceLoader::continueAfterContentPolicy(PolicyAction contentPolicy, const ResourceResponse& r)

[cpp] view plaincopy

1. void MainResourceLoader::continueAfterContentPolicy(  
2.     PolicyAction contentPolicy, const ResourceResponse& r)  
3. {  
4.     KURL url = request().url();  
5.     const String& mimeType = r.mimeType();  
6.       
7.     switch (contentPolicy) {  
8.     case PolicyUse: {  
9.         .....  
10.         break;  
11.     }  
12.   
13.     case PolicyDownload:  
14.        .....  
15.         return;  
16.     .......  
17. }  

9.void FrameLoaderClientAndroid::download(ResourceHandle* handle, const ResourceRequest&)

[cpp] view plaincopy

1. handle->getInternal()->m_loader->downloadFile();  

10.  ResourceLoaderAndroid->downloadFile()

for apache stack

11. void WebCoreResourceLoader::downloadFile()

[cpp] view plaincopy

1. env->CallVoidMethod(mJLoader, gResourceLoader.mDownloadFileMethodID);   

12.LoadListener.downloadFile().

[cpp] view plaincopy

1. mBrowserFrame.getCallbackProxy().onDownloadStart()  

......

for chromium stack

11.WebURLLoader->downloadFile();

12.WebUrlLoaderClient->downlaodFile()

13.WebCoreFrameBridge.cpp->downloadStart(m_response->getUrl(), m_request->getUserAgent(), contentDisposition, m_response->getMimeType(), m_response->getExpectedSize());

14. BrowserFrame.downloadStart()

to downloadManager

main resource when to check media type?

MainResourceLoader receive data to checkType
1.MainResourceLoader::didReceiveResponse
is a subBranch of the parse process.
in the main Branch 
FrameLoaderClient::committedLoad will call DocumentLoader::commitData
but it will also call MainResourceLoader::didReceiveResponse,by the way.
2.PolicyChecker::checkContentPolicy
FrameLoaderClientAndroid::
call TreatAsAttachment and canShowMIMEType to determine
call "DOMImplementation::isTextMIMEType"

come from http://blog.csdn.net/elfylin/article/details/7093832