WebCore/html/FileReader.h
changeset 0 4f2f89ce4247
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/WebCore/html/FileReader.h	Fri Sep 17 09:02:29 2010 +0300
@@ -0,0 +1,171 @@
+/*
+ * Copyright (C) 2010 Google Inc.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef FileReader_h
+#define FileReader_h
+
+#if ENABLE(FILE_READER)
+
+#include "ActiveDOMObject.h"
+#include "EventTarget.h"
+#include "FileError.h"
+#include "FileStreamClient.h"
+#include "PlatformString.h"
+#include "ScriptString.h"
+#include "TextEncoding.h"
+#include <wtf/PassRefPtr.h>
+#include <wtf/RefCounted.h>
+#include <wtf/RefPtr.h>
+#include <wtf/Vector.h>
+
+namespace WebCore {
+
+class Blob;
+class File;
+class FileStreamProxy;
+class ScriptExecutionContext;
+class TextResourceDecoder;
+
+class FileReader : public RefCounted<FileReader>, public ActiveDOMObject, public EventTarget, public FileStreamClient {
+public:
+    static PassRefPtr<FileReader> create(ScriptExecutionContext* context)
+    {
+        return adoptRef(new FileReader(context));
+    }
+
+    virtual ~FileReader();
+
+    enum ReadyState {
+        Empty = 0,
+        Loading = 1,
+        Done = 2
+    };
+
+    void readAsBinaryString(Blob*);
+    void readAsText(Blob*, const String& encoding = "");
+    void readAsDataURL(File*);
+    void abort();
+
+    ReadyState readyState() const;
+    PassRefPtr<FileError> error() { return m_error; }
+    const ScriptString& result();
+
+    // ActiveDOMObject
+    virtual bool canSuspend() const;
+    virtual void stop();
+    virtual bool hasPendingActivity() const;
+
+    // EventTarget
+    virtual FileReader* toFileReader() { return this; }
+    virtual ScriptExecutionContext* scriptExecutionContext() const { return ActiveDOMObject::scriptExecutionContext(); }
+
+    // FileStreamClient
+    virtual void didStart();
+    virtual void didGetSize(long long);
+    virtual void didRead(const char*, int);
+    virtual void didFinish();
+    virtual void didFail(ExceptionCode);
+
+    using RefCounted<FileReader>::ref;
+    using RefCounted<FileReader>::deref;
+
+    DEFINE_ATTRIBUTE_EVENT_LISTENER(loadstart);
+    DEFINE_ATTRIBUTE_EVENT_LISTENER(progress);
+    DEFINE_ATTRIBUTE_EVENT_LISTENER(load);
+    DEFINE_ATTRIBUTE_EVENT_LISTENER(abort);
+    DEFINE_ATTRIBUTE_EVENT_LISTENER(error);
+    DEFINE_ATTRIBUTE_EVENT_LISTENER(loadend);
+
+private:
+    enum ReadType {
+        ReadFileAsBinaryString,
+        ReadFileAsText,
+        ReadFileAsDataURL
+    };
+    enum InternalState {
+        None,
+        Starting,
+        Opening,
+        Reading,
+        Completed
+    };
+
+    FileReader(ScriptExecutionContext*);
+
+    // EventTarget
+    virtual void refEventTarget() { ref(); }
+    virtual void derefEventTarget() { deref(); }
+    virtual EventTargetData* eventTargetData() { return &m_eventTargetData; }
+    virtual EventTargetData* ensureEventTargetData() { return &m_eventTargetData; }
+
+    void terminate();
+    void readInternal(Blob*, ReadType);
+    void fireEvent(const AtomicString& type);
+    void convertToText();
+    void convertToDataURL();
+
+    InternalState m_state;
+    EventTargetData m_eventTargetData;
+
+    RefPtr<Blob> m_fileBlob;
+    ReadType m_readType;
+    TextEncoding m_encoding;
+
+    // Like XMLHttpRequest.m_responseText, we keep this as a ScriptString, not a WebCore::String.
+    // That's because these strings can easily get huge (they are filled from the file) and
+    // because JS can easily observe many intermediate states, so it's very useful to be
+    // able to share the buffer with JavaScript versions of the whole or partial string.
+    // In contrast, this string doesn't interact much with the rest of the engine so it's not that
+    // big a cost that it isn't a String.
+    ScriptString m_result;
+
+    // The raw data. We have to keep track of all the raw data for it to be converted to text or data URL data.
+    Vector<char> m_rawData;
+    bool m_isRawDataConverted;
+
+    // The decoder used to decode the text data.
+    RefPtr<TextResourceDecoder> m_decoder;
+
+    // Needed to create data URL.
+    String m_fileType;
+
+    RefPtr<FileStreamProxy> m_streamProxy;
+    Vector<char> m_buffer;
+    RefPtr<FileError> m_error;
+    long long m_bytesLoaded;
+    long long m_totalBytes;
+    double m_lastProgressNotificationTimeMS;
+};
+
+} // namespace WebCore
+
+#endif
+
+#endif // FileReader_h