1// Copyright 2014 The Chromium Authors. All rights reserved.
2// Copyright (C) 2016 Apple Inc. All rights reserved.
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29
30#include "config.h"
31#include "CSSParserTokenRange.h"
32
33#include "StyleSheetContents.h"
34#include <wtf/NeverDestroyed.h>
35#include <wtf/text/StringBuilder.h>
36
37namespace WebCore {
38
39CSSParserToken& CSSParserTokenRange::eofToken()
40{
41 static NeverDestroyed<CSSParserToken> eofToken(EOFToken);
42 return eofToken.get();
43}
44
45CSSParserTokenRange CSSParserTokenRange::makeSubRange(const CSSParserToken* first, const CSSParserToken* last) const
46{
47 if (first == &eofToken())
48 first = m_last;
49 if (last == &eofToken())
50 last = m_last;
51 ASSERT(first <= last);
52 return CSSParserTokenRange(first, last);
53}
54
55CSSParserTokenRange CSSParserTokenRange::consumeBlock()
56{
57 ASSERT(peek().getBlockType() == CSSParserToken::BlockStart);
58 const CSSParserToken* start = &peek() + 1;
59 unsigned nestingLevel = 0;
60 do {
61 const CSSParserToken& token = consume();
62 if (token.getBlockType() == CSSParserToken::BlockStart)
63 nestingLevel++;
64 else if (token.getBlockType() == CSSParserToken::BlockEnd)
65 nestingLevel--;
66 } while (nestingLevel && m_first < m_last);
67
68 if (nestingLevel)
69 return makeSubRange(start, m_first); // Ended at EOF
70 return makeSubRange(start, m_first - 1);
71}
72
73CSSParserTokenRange CSSParserTokenRange::consumeBlockCheckingForEditability(StyleSheetContents* styleSheet)
74{
75 ASSERT(peek().getBlockType() == CSSParserToken::BlockStart);
76 const auto* start = &peek() + 1;
77 unsigned nestingLevel = 0;
78 do {
79 const auto& token = consume();
80 if (token.getBlockType() == CSSParserToken::BlockStart)
81 nestingLevel++;
82 else if (token.getBlockType() == CSSParserToken::BlockEnd)
83 nestingLevel--;
84
85 if (styleSheet && !styleSheet->usesStyleBasedEditability() && token.type() == IdentToken && equalLettersIgnoringASCIICase(token.value(), "-webkit-user-modify"))
86 styleSheet->parserSetUsesStyleBasedEditability();
87 } while (nestingLevel && m_first < m_last);
88
89 if (nestingLevel)
90 return makeSubRange(start, m_first); // Ended at EOF
91 return makeSubRange(start, m_first - 1);
92}
93
94void CSSParserTokenRange::consumeComponentValue()
95{
96 // FIXME: This is going to do multiple passes over large sections of a stylesheet.
97 // We should consider optimising this by precomputing where each block ends.
98 unsigned nestingLevel = 0;
99 do {
100 const CSSParserToken& token = consume();
101 if (token.getBlockType() == CSSParserToken::BlockStart)
102 nestingLevel++;
103 else if (token.getBlockType() == CSSParserToken::BlockEnd)
104 nestingLevel--;
105 } while (nestingLevel && m_first < m_last);
106}
107
108String CSSParserTokenRange::serialize() const
109{
110 // We're supposed to insert comments between certain pairs of token types
111 // as per spec, but since this is currently only used for @supports CSSOM
112 // we just get these cases wrong and avoid the additional complexity.
113 StringBuilder builder;
114 for (const CSSParserToken* it = m_first; it < m_last; ++it)
115 it->serialize(builder);
116 return builder.toString();
117}
118
119} // namespace WebCore
120