1 : /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
2 : * ***** BEGIN LICENSE BLOCK *****
3 : * Version: MPL 1.1/GPL 2.0/LGPL 2.1
4 : *
5 : * The contents of this file are subject to the Mozilla Public License Version
6 : * 1.1 (the "License"); you may not use this file except in compliance with
7 : * the License. You may obtain a copy of the License at
8 : * http://www.mozilla.org/MPL/
9 : *
10 : * Software distributed under the License is distributed on an "AS IS" basis,
11 : * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
12 : * for the specific language governing rights and limitations under the
13 : * License.
14 : *
15 : * The Original Code is Novell code.
16 : *
17 : * The Initial Developer of the Original Code is Novell Corporation.
18 : * Portions created by the Initial Developer are Copyright (C) 2006
19 : * the Initial Developer. All Rights Reserved.
20 : *
21 : * Contributor(s):
22 : * robert@ocallahan.org
23 : * Ehsan Akhgari <ehsan.akhgari@gmail.com>
24 : *
25 : * Alternatively, the contents of this file may be used under the terms of
26 : * either the GNU General Public License Version 2 or later (the "GPL"), or
27 : * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
28 : * in which case the provisions of the GPL or the LGPL are applicable instead
29 : * of those above. If you wish to allow use of your version of this file only
30 : * under the terms of either the GPL or the LGPL, and not to allow others to
31 : * use your version of this file under the terms of the MPL, indicate your
32 : * decision by deleting the provisions above and replace them with the notice
33 : * and other provisions required by the GPL or the LGPL. If you do not delete
34 : * the provisions above, a recipient may use your version of this file under
35 : * the terms of any one of the MPL, the GPL or the LGPL.
36 : *
37 : * ***** END LICENSE BLOCK ***** */
38 :
39 : #ifndef NSTEXTFRAMEUTILS_H_
40 : #define NSTEXTFRAMEUTILS_H_
41 :
42 : #include "gfxFont.h"
43 : #include "gfxSkipChars.h"
44 : #include "nsTextFragment.h"
45 :
46 : #define BIG_TEXT_NODE_SIZE 4096
47 :
48 : #define CH_NBSP 160
49 : #define CH_SHY 173
50 : #define CH_CJKSP 12288 // U+3000 IDEOGRAPHIC SPACE (CJK Full-Width Space)
51 :
52 : #define CH_LRM 8206 //<!ENTITY lrm CDATA "‎" -- left-to-right mark, U+200E NEW RFC 2070 -->
53 : #define CH_RLM 8207 //<!ENTITY rlm CDATA "‏" -- right-to-left mark, U+200F NEW RFC 2070 -->
54 : #define CH_LRE 8234 //<!CDATA "‪" -- left-to-right embedding, U+202A -->
55 : #define CH_RLO 8238 //<!CDATA "‮" -- right-to-left override, U+202E -->
56 :
57 : class nsTextFrameUtils {
58 : public:
59 : // These constants are used as textrun flags for textframe textruns.
60 : enum {
61 : // The following flags are set by TransformText
62 :
63 : // the text has at least one untransformed tab character
64 : TEXT_HAS_TAB = 0x010000,
65 : // the original text has at least one soft hyphen character
66 : TEXT_HAS_SHY = 0x020000,
67 : TEXT_WAS_TRANSFORMED = 0x040000,
68 : TEXT_UNUSED_FLAG = 0x080000,
69 :
70 : // The following flags are set by nsTextFrame
71 :
72 : TEXT_IS_SIMPLE_FLOW = 0x100000,
73 : TEXT_INCOMING_WHITESPACE = 0x200000,
74 : TEXT_TRAILING_WHITESPACE = 0x400000,
75 : TEXT_COMPRESSED_LEADING_WHITESPACE = 0x800000,
76 : TEXT_NO_BREAKS = 0x1000000,
77 : TEXT_IS_TRANSFORMED = 0x2000000,
78 : // This gets set if there's a break opportunity at the end of the textrun.
79 : // We normally don't use this break opportunity because the following text
80 : // will have a break opportunity at the start, but it's useful for line
81 : // layout to know about it in case the following content is not text
82 : TEXT_HAS_TRAILING_BREAK = 0x4000000
83 :
84 : // The following are defined by gfxTextRunWordCache rather than here,
85 : // so that it also has access to the _INCOMING flag
86 : // TEXT_TRAILING_ARABICCHAR
87 : // TEXT_INCOMING_ARABICCHAR
88 : };
89 :
90 : // These constants are used in TransformText to represent context information
91 : // from previous textruns.
92 : enum {
93 : INCOMING_NONE = 0,
94 : INCOMING_WHITESPACE = 1,
95 : INCOMING_ARABICCHAR = 2
96 : };
97 :
98 : /**
99 : * Returns true if aChars/aLength are something that make a space
100 : * character not be whitespace when they follow the space character.
101 : * For now, this is true if and only if aChars starts with a ZWJ. (This
102 : * is what Uniscribe assumes.)
103 : */
104 : static bool
105 0 : IsSpaceCombiningSequenceTail(const PRUnichar* aChars, PRInt32 aLength) {
106 0 : return aLength > 0 && aChars[0] == 0x200D; // ZWJ
107 : }
108 :
109 : enum CompressionMode {
110 : COMPRESS_NONE,
111 : COMPRESS_WHITESPACE,
112 : COMPRESS_WHITESPACE_NEWLINE
113 : };
114 :
115 : /**
116 : * Create a text run from a run of Unicode text. The text may have whitespace
117 : * compressed. A preformatted tab is sent to the text run as a single space.
118 : * (Tab spacing must be performed by textframe later.) Certain other
119 : * characters are discarded.
120 : *
121 : * @param aCompressWhitespace control what is compressed to a
122 : * single space character: no compression, compress spaces (not followed
123 : * by combining mark) and tabs, and compress those plus newlines.
124 : * @param aIncomingFlags a flag indicating whether there was whitespace
125 : * or an Arabic character preceding this text. We set it to indicate if
126 : * there's an Arabic character or whitespace preceding the end of this text.
127 : */
128 : static PRUnichar* TransformText(const PRUnichar* aText, PRUint32 aLength,
129 : PRUnichar* aOutput,
130 : CompressionMode aCompression,
131 : PRUint8 * aIncomingFlags,
132 : gfxSkipCharsBuilder* aSkipChars,
133 : PRUint32* aAnalysisFlags);
134 :
135 : static PRUint8* TransformText(const PRUint8* aText, PRUint32 aLength,
136 : PRUint8* aOutput,
137 : CompressionMode aCompression,
138 : PRUint8 * aIncomingFlags,
139 : gfxSkipCharsBuilder* aSkipChars,
140 : PRUint32* aAnalysisFlags);
141 :
142 : static void
143 0 : AppendLineBreakOffset(nsTArray<PRUint32>* aArray, PRUint32 aOffset)
144 : {
145 0 : if (aArray->Length() > 0 && (*aArray)[aArray->Length() - 1] == aOffset)
146 0 : return;
147 0 : aArray->AppendElement(aOffset);
148 : }
149 :
150 : };
151 :
152 : class nsSkipCharsRunIterator {
153 : public:
154 : enum LengthMode {
155 : LENGTH_UNSKIPPED_ONLY = false,
156 : LENGTH_INCLUDES_SKIPPED = true
157 : };
158 0 : nsSkipCharsRunIterator(const gfxSkipCharsIterator& aStart,
159 : LengthMode aLengthIncludesSkipped, PRUint32 aLength)
160 : : mIterator(aStart), mRemainingLength(aLength), mRunLength(0),
161 : mVisitSkipped(false),
162 0 : mLengthIncludesSkipped(aLengthIncludesSkipped) {
163 0 : }
164 0 : void SetVisitSkipped() { mVisitSkipped = true; }
165 0 : void SetOriginalOffset(PRInt32 aOffset) {
166 0 : mIterator.SetOriginalOffset(aOffset);
167 0 : }
168 0 : void SetSkippedOffset(PRUint32 aOffset) {
169 0 : mIterator.SetSkippedOffset(aOffset);
170 0 : }
171 :
172 : // guaranteed to return only positive-length runs
173 : bool NextRun();
174 0 : bool IsSkipped() const { return mSkipped; }
175 : // Always returns something > 0
176 0 : PRInt32 GetRunLength() const { return mRunLength; }
177 0 : const gfxSkipCharsIterator& GetPos() const { return mIterator; }
178 0 : PRInt32 GetOriginalOffset() const { return mIterator.GetOriginalOffset(); }
179 0 : PRUint32 GetSkippedOffset() const { return mIterator.GetSkippedOffset(); }
180 :
181 : private:
182 : gfxSkipCharsIterator mIterator;
183 : PRInt32 mRemainingLength;
184 : PRInt32 mRunLength;
185 : bool mSkipped;
186 : bool mVisitSkipped;
187 : bool mLengthIncludesSkipped;
188 : };
189 :
190 : #endif /*NSTEXTFRAMEUTILS_H_*/
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