1 /*
2 * Copyright (C) 2013 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
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY GOOGLE INC. ``AS IS'' AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL GOOGLE INC. OR
17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26 #include "config.h"
27 #include "core/html/parser/BackgroundHTMLInputStream.h"
28
29 namespace blink {
30
BackgroundHTMLInputStream()31 BackgroundHTMLInputStream::BackgroundHTMLInputStream()
32 : m_firstValidCheckpointIndex(0)
33 , m_firstValidSegmentIndex(0)
34 , m_totalCheckpointTokenCount(0)
35 {
36 }
37
append(const String & input)38 void BackgroundHTMLInputStream::append(const String& input)
39 {
40 m_current.append(SegmentedString(input));
41 m_segments.append(input);
42 }
43
close()44 void BackgroundHTMLInputStream::close()
45 {
46 m_current.close();
47 }
48
createCheckpoint(size_t tokensExtractedSincePreviousCheckpoint)49 HTMLInputCheckpoint BackgroundHTMLInputStream::createCheckpoint(size_t tokensExtractedSincePreviousCheckpoint)
50 {
51 HTMLInputCheckpoint checkpoint = m_checkpoints.size();
52 m_checkpoints.append(Checkpoint(m_current, m_segments.size(), tokensExtractedSincePreviousCheckpoint));
53 m_totalCheckpointTokenCount += tokensExtractedSincePreviousCheckpoint;
54 return checkpoint;
55 }
56
invalidateCheckpointsBefore(HTMLInputCheckpoint newFirstValidCheckpointIndex)57 void BackgroundHTMLInputStream::invalidateCheckpointsBefore(HTMLInputCheckpoint newFirstValidCheckpointIndex)
58 {
59 ASSERT(newFirstValidCheckpointIndex < m_checkpoints.size());
60 // There is nothing to do for the first valid checkpoint.
61 if (m_firstValidCheckpointIndex == newFirstValidCheckpointIndex)
62 return;
63
64 ASSERT(newFirstValidCheckpointIndex > m_firstValidCheckpointIndex);
65 const Checkpoint& lastInvalidCheckpoint = m_checkpoints[newFirstValidCheckpointIndex - 1];
66
67 ASSERT(m_firstValidSegmentIndex <= lastInvalidCheckpoint.numberOfSegmentsAlreadyAppended);
68 for (size_t i = m_firstValidSegmentIndex; i < lastInvalidCheckpoint.numberOfSegmentsAlreadyAppended; ++i)
69 m_segments[i] = String();
70 m_firstValidSegmentIndex = lastInvalidCheckpoint.numberOfSegmentsAlreadyAppended;
71
72 for (size_t i = m_firstValidCheckpointIndex; i < newFirstValidCheckpointIndex; ++i)
73 m_checkpoints[i].clear();
74 m_firstValidCheckpointIndex = newFirstValidCheckpointIndex;
75
76 updateTotalCheckpointTokenCount();
77 }
78
rewindTo(HTMLInputCheckpoint checkpointIndex,const String & unparsedInput)79 void BackgroundHTMLInputStream::rewindTo(HTMLInputCheckpoint checkpointIndex, const String& unparsedInput)
80 {
81 ASSERT(checkpointIndex < m_checkpoints.size()); // If this ASSERT fires, checkpointIndex is invalid.
82 const Checkpoint& checkpoint = m_checkpoints[checkpointIndex];
83 ASSERT(!checkpoint.isNull());
84
85 bool isClosed = m_current.isClosed();
86
87 m_current = checkpoint.input;
88
89 for (size_t i = checkpoint.numberOfSegmentsAlreadyAppended; i < m_segments.size(); ++i) {
90 ASSERT(!m_segments[i].isNull());
91 m_current.append(SegmentedString(m_segments[i]));
92 }
93
94 if (!unparsedInput.isEmpty())
95 m_current.prepend(SegmentedString(unparsedInput));
96
97 if (isClosed && !m_current.isClosed())
98 m_current.close();
99
100 ASSERT(m_current.isClosed() == isClosed);
101
102 m_segments.clear();
103 m_checkpoints.clear();
104 m_firstValidCheckpointIndex = 0;
105 m_firstValidSegmentIndex = 0;
106
107 updateTotalCheckpointTokenCount();
108 }
109
updateTotalCheckpointTokenCount()110 void BackgroundHTMLInputStream::updateTotalCheckpointTokenCount()
111 {
112 m_totalCheckpointTokenCount = 0;
113 size_t lastCheckpointIndex = m_checkpoints.size();
114 for (size_t i = 0; i < lastCheckpointIndex; ++i)
115 m_totalCheckpointTokenCount += m_checkpoints[i].tokensExtractedSincePreviousCheckpoint;
116 }
117
118 }
119