Simplify HTMLInputStream

sky/engine/core/html/parser/HTMLInputStream.h

-/*
- * 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:
- * 1. Redistributions of source code must retain the above copyright
- *    notice, this list of conditions and the following disclaimer.
- * 2. 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.
- *
- * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``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 APPLE INC. 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.
- */
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
 
 #ifndef HTMLInputStream_h
 #define HTMLInputStream_h
 
 #include "core/html/parser/InputStreamPreprocessor.h"
 #include "platform/text/SegmentedString.h"
 
 namespace blink {
 
-// The InputStream is made up of a sequence of SegmentedStrings:
-//
-// [--current--][--next--][--next--] ... [--next--]
-//            /\                         (also called m_last)
-//            L_ current insertion point
-//
-// The current segmented string is stored in InputStream.  Each of the
-// afterInsertionPoint buffers are stored in InsertionPointRecords on the
-// stack.
-//
-// We remove characters from the "current" string in the InputStream.
-// document.write() will add characters at the current insertion point,
-// which appends them to the "current" string.
-//
-// m_last is a pointer to the last of the afterInsertionPoint strings.
-// The network adds data at the end of the InputStream, which appends
-// them to the "last" string.
 class HTMLInputStream {
     WTF_MAKE_NONCOPYABLE(HTMLInputStream);
 public:
-    HTMLInputStream()
-        : m_last(&m_first)
-    {
-    }
+    HTMLInputStream() { }
 
     void appendToEnd(const SegmentedString& string)
     {
-        m_last->append(string);
-    }
-
-    void insertAtCurrentInsertionPoint(const SegmentedString& string)
-    {
-        m_first.append(string);
-    }
-
-    bool hasInsertionPoint() const
-    {
-        return &m_first != m_last;
+        m_string.append(string);
     }
 
     void markEndOfFile()
     {
-        m_last->append(SegmentedString(String(&kEndOfFileMarker, 1)));
-        m_last->close();
+        m_string.append(SegmentedString(String(&kEndOfFileMarker, 1)));
+        m_string.close();
     }
 
-    void closeWithoutMarkingEndOfFile()
-    {
-        m_last->close();
-    }
-
-    bool haveSeenEndOfFile() const
-    {
-        return m_last->isClosed();
-    }
-
-    SegmentedString& current() { return m_first; }
-    const SegmentedString& current() const { return m_first; }
-
-    void splitInto(SegmentedString& next)
-    {
-        next = m_first;
-        m_first = SegmentedString();
-        if (m_last == &m_first) {
-            // We used to only have one SegmentedString in the InputStream
-            // but now we have two.  That means m_first is no longer also
-            // the m_last string, |next| is now the last one.
-            m_last = &next;
-        }
-    }
-
-    void mergeFrom(SegmentedString& next)
-    {
-        m_first.append(next);
-        if (m_last == &next) {
-            // The string |next| used to be the last SegmentedString in
-            // the InputStream.  Now that it's been merged into m_first,
-            // that makes m_first the last one.
-            m_last = &m_first;
-        }
-        if (next.isClosed()) {
-            // We also need to merge the "closed" state from next to
-            // m_first.  Arguably, this work could be done in append().
-            m_first.close();
-        }
-    }
+    SegmentedString& current() { return m_string; }
+    const SegmentedString& current() const { return m_string; }
 
 private:
-    SegmentedString m_first;
-    SegmentedString* m_last;
-};
-
-class InsertionPointRecord {
-    WTF_MAKE_NONCOPYABLE(InsertionPointRecord);
-public:
-    explicit InsertionPointRecord(HTMLInputStream& inputStream)
-        : m_inputStream(&inputStream)
-    {
-        m_line = m_inputStream->current().currentLine();
-        m_column = m_inputStream->current().currentColumn();
-        m_inputStream->splitInto(m_next);
-        // We 'fork' current position and use it for the generated script part.
-        // This is a bit weird, because generated part does not have positions within an HTML document.
-        m_inputStream->current().setCurrentPosition(m_line, m_column, 0);
-    }
-
-    ~InsertionPointRecord()
-    {
-        // Some inserted text may have remained in input stream. E.g. if script has written "&amp" or "<table",
-        // it stays in buffer because it cannot be properly tokenized before we see next part.
-        int unparsedRemainderLength = m_inputStream->current().length();
-        m_inputStream->mergeFrom(m_next);
-        // We restore position for the character that goes right after unparsed remainder.
-        m_inputStream->current().setCurrentPosition(m_line, m_column, unparsedRemainderLength);
-    }
-
-private:
-    HTMLInputStream* m_inputStream;
-    SegmentedString m_next;
-    OrdinalNumber m_line;
-    OrdinalNumber m_column;
+    SegmentedString m_string;
 };
 
 }
 
 #endif