1 /*
2  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
3  *
4  * This code is free software; you can redistribute it and/or modify it
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6  * published by the Free Software Foundation.  Oracle designates this
7  * particular file as subject to the "Classpath" exception as provided
8  * by Oracle in the LICENSE file that accompanied this code.
9  *
10  * This code is distributed in the hope that it will be useful, but WITHOUT
11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
13  * version 2 for more details (a copy is included in the LICENSE file that
14  * accompanied this code).
15  *
16  * You should have received a copy of the GNU General Public License version
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18  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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25 
26 /*
27  *
28  * (C) Copyright IBM Corp and Others. 1998-2013 - All Rights Reserved
29  *
30  */
31 
32 #include "LETypes.h"
33 #include "MorphTables.h"
34 #include "StateTables.h"
35 #include "MorphStateTables.h"
36 #include "SubtableProcessor2.h"
37 #include "StateTableProcessor2.h"
38 #include "LigatureSubstProc2.h"
39 #include "LEGlyphStorage.h"
40 #include "LESwaps.h"
41 
42 U_NAMESPACE_BEGIN
43 
44 #define ExtendedComplement(m) ((le_int32) (~((le_uint32) (m))))
45 #define SignBit(m) ((ExtendedComplement(m) >> 1) & (le_int32)(m))
46 #define SignExtend(v,m) (((v) & SignBit(m))? ((v) | ExtendedComplement(m)): (v))
47 
UOBJECT_DEFINE_RTTI_IMPLEMENTATION(LigatureSubstitutionProcessor2)48 UOBJECT_DEFINE_RTTI_IMPLEMENTATION(LigatureSubstitutionProcessor2)
49 
50 LigatureSubstitutionProcessor2::LigatureSubstitutionProcessor2(const LEReferenceTo<MorphSubtableHeader2> &morphSubtableHeader, LEErrorCode &success)
51   : StateTableProcessor2(morphSubtableHeader, success),
52   ligActionOffset(0),
53   ligatureSubstitutionHeader(morphSubtableHeader, success), componentOffset(0), ligatureOffset(0), entryTable()
54 {
55     if (LE_FAILURE(success)) return;
56 
57     ligActionOffset = SWAPL(ligatureSubstitutionHeader->ligActionOffset);
58     componentOffset = SWAPL(ligatureSubstitutionHeader->componentOffset);
59     ligatureOffset = SWAPL(ligatureSubstitutionHeader->ligatureOffset);
60 
61     entryTable = LEReferenceToArrayOf<LigatureSubstitutionStateEntry2>(stHeader, success, entryTableOffset, LE_UNBOUNDED_ARRAY);
62 }
63 
~LigatureSubstitutionProcessor2()64 LigatureSubstitutionProcessor2::~LigatureSubstitutionProcessor2()
65 {
66 }
67 
beginStateTable()68 void LigatureSubstitutionProcessor2::beginStateTable()
69 {
70     m = -1;
71 }
72 
processStateEntry(LEGlyphStorage & glyphStorage,le_int32 & currGlyph,EntryTableIndex2 index,LEErrorCode & success)73 le_uint16 LigatureSubstitutionProcessor2::processStateEntry(LEGlyphStorage &glyphStorage, le_int32 &currGlyph, EntryTableIndex2 index, LEErrorCode &success)
74 {
75     const LigatureSubstitutionStateEntry2 *entry = entryTable.getAlias(index, success);
76     if(LE_FAILURE(success)) return 0;
77 
78     le_uint16 nextStateIndex = SWAPW(entry->nextStateIndex);
79     le_uint16 flags = SWAPW(entry->entryFlags);
80     le_uint16 ligActionIndex = SWAPW(entry->ligActionIndex);
81 
82     if (flags & lsfSetComponent) {
83         if (++m >= nComponents) {
84             m = 0;
85         }
86         componentStack[m] = currGlyph;
87     } else if ( m == -1) {
88         // bad font- skip this glyph.
89         //LE_DEBUG_BAD_FONT("m==-1 (componentCount went negative)")
90         currGlyph+= dir;
91         return nextStateIndex;
92     }
93 
94     ByteOffset actionOffset = flags & lsfPerformAction;
95 
96     if (actionOffset != 0) {
97         LEReferenceTo<LigatureActionEntry> ap(stHeader, success, ligActionOffset); // byte offset
98         if (LE_FAILURE(success)) {
99             currGlyph+= dir;
100             return nextStateIndex;
101         }
102         ap.addObject(ligActionIndex, success);
103         LEReferenceToArrayOf<TTGlyphID> ligatureTable(stHeader, success, ligatureOffset, LE_UNBOUNDED_ARRAY);
104         LigatureActionEntry action;
105         le_int32 offset, i = 0, j = 0;
106         le_int32 stack[nComponents];
107         le_int16 mm = -1;
108 
109         LEReferenceToArrayOf<le_uint16> componentTable(stHeader, success, componentOffset, LE_UNBOUNDED_ARRAY);
110         if(LE_FAILURE(success)) {
111           currGlyph+= dir;
112           return nextStateIndex; // get out! bad font
113         }
114 
115         do {
116             le_uint32 componentGlyph = componentStack[m--]; // pop off
117 
118             if (j++ > 0) {
119                 ap.addObject(success);
120             }
121             if (LE_FAILURE(success)) {
122                 currGlyph+= dir;
123                 return nextStateIndex;
124             }
125 
126             action = SWAPL(*ap.getAlias());
127 
128             if (m < 0) {
129                 m = nComponents - 1;
130             }
131 
132             offset = action & lafComponentOffsetMask;
133             if (offset != 0) {
134                 if(componentGlyph >= glyphStorage.getGlyphCount()) {
135                   LE_DEBUG_BAD_FONT("preposterous componentGlyph");
136                   currGlyph+= dir;
137                   return nextStateIndex; // get out! bad font
138                 }
139                 i += SWAPW(componentTable(LE_GET_GLYPH(glyphStorage[componentGlyph]) + (SignExtend(offset, lafComponentOffsetMask)),success));
140                 if (LE_FAILURE(success)) {
141                     currGlyph+= dir;
142                     return nextStateIndex;
143                 }
144 
145                 if (action & (lafLast | lafStore))  {
146                   TTGlyphID ligatureGlyph = SWAPW(ligatureTable(i,success));
147                   if (LE_FAILURE(success)) {
148                       currGlyph+= dir;
149                       return nextStateIndex;
150                   }
151                     glyphStorage[componentGlyph] = LE_SET_GLYPH(glyphStorage[componentGlyph], ligatureGlyph);
152                     if(mm==nComponents) {
153                       LE_DEBUG_BAD_FONT("exceeded nComponents");
154                       mm--; // don't overrun the stack.
155                     }
156                     stack[++mm] = componentGlyph;
157                     i = 0;
158                 } else {
159                     glyphStorage[componentGlyph] = LE_SET_GLYPH(glyphStorage[componentGlyph], 0xFFFF);
160                 }
161             }
162 #if LE_ASSERT_BAD_FONT
163             if(m<0) {
164               LE_DEBUG_BAD_FONT("m<0")
165             }
166 #endif
167         } while (LE_SUCCESS(success) && !(action & lafLast) && (m>=0) ); // stop if last bit is set, or if run out of items
168 
169         while (mm >= 0) {
170             if (++m >= nComponents) {
171                 m = 0;
172             }
173 
174             componentStack[m] = stack[mm--];
175         }
176     }
177 
178     if (!(flags & lsfDontAdvance)) {
179         currGlyph += dir;
180     }
181 
182     return nextStateIndex;
183 }
184 
endStateTable()185 void LigatureSubstitutionProcessor2::endStateTable()
186 {
187 }
188 
189 U_NAMESPACE_END
190