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2 *
3 *   © 2016 and later: Unicode, Inc. and others.
4 *   License & terms of use: http://www.unicode.org/copyright.html
5 *
6 ***************************************************************************
7 ***************************************************************************
8 *
9 *   Copyright (C) 1998-2013, International Business Machines
10 *   Corporation and others.  All Rights Reserved.
11 *
12 ************************************************************************/
13 
14 #include "layout/LETypes.h"
15 #include "layout/LESwaps.h"
16 
17 #include "sfnt.h"
18 #include "cmaps.h"
19 #include <stdio.h>
20 
21 #define SWAPU16(code) ((LEUnicode16) SWAPW(code))
22 #define SWAPU32(code) ((LEUnicode32) SWAPL(code))
23 
24 //
25 // Finds the high bit by binary searching
26 // through the bits in value.
27 //
highBit(le_uint32 value)28 le_int8 highBit(le_uint32 value)
29 {
30     le_uint8 bit = 0;
31 
32     if (value >= 1 << 16) {
33         value >>= 16;
34         bit += 16;
35     }
36 
37     if (value >= 1 << 8) {
38         value >>= 8;
39         bit += 8;
40     }
41 
42     if (value >= 1 << 4) {
43         value >>= 4;
44         bit += 4;
45     }
46 
47     if (value >= 1 << 2) {
48         value >>= 2;
49         bit += 2;
50     }
51 
52     if (value >= 1 << 1) {
53         value >>= 1;
54         bit += 1;
55     }
56 
57     return bit;
58 }
59 
createUnicodeMapper(const CMAPTable * cmap)60 CMAPMapper *CMAPMapper::createUnicodeMapper(const CMAPTable *cmap)
61 {
62     le_uint16 i;
63     le_uint16 nSubtables = SWAPW(cmap->numberSubtables);
64     const CMAPEncodingSubtable *subtable = NULL;
65     le_bool found = FALSE;
66     le_uint16 foundPlatformID = 0xFFFF;
67     le_uint16 foundPlatformSpecificID = 0xFFFF;
68     le_uint32 foundOffset = 0;
69     le_uint16 foundTable = 0xFFFF;
70     // first pass, look for MS table. (preferred?)
71     for (i = 0; i < nSubtables && !found; i += 1) {
72         const CMAPEncodingSubtableHeader *esh = &cmap->encodingSubtableHeaders[i];
73 
74         le_uint16 platformID = SWAPW(esh->platformID);
75         le_uint16 platformSpecificID = SWAPW(esh->platformSpecificID);
76         if (platformID == 3) { // microsoft
77           switch (platformSpecificID) {
78             case 1: // Unicode BMP (UCS-2)
79             case 10: // Unicode UCS-4
80                 foundOffset = SWAPL(esh->encodingOffset);
81                 foundPlatformID = platformID;
82                 foundPlatformSpecificID = platformSpecificID;
83                 found = TRUE;
84                 foundTable = i;
85                 break;
86 
87                 //default:
88               //              printf("%s:%d: microsoft (3) platform specific ID %d (wanted 1 or 10) for subtable %d/%d\n", __FILE__, __LINE__, (SWAPW(esh->platformSpecificID)), i, nSubtables);
89             }
90         } else {
91           //printf("%s:%d: platform  ID %d (wanted 3, microsoft) for subtable %d/%d\n", __FILE__, __LINE__, (SWAPW(esh->platformID)), i, nSubtables);
92         }
93     }
94 
95     // second pass, allow non MS table
96     // first pass, look for MS table. (preferred?)
97       for (i = 0; i < nSubtables && !found; i += 1) {
98         const CMAPEncodingSubtableHeader *esh = &cmap->encodingSubtableHeaders[i];
99         le_uint16 platformID = SWAPW(esh->platformID);
100         le_uint16 platformSpecificID = SWAPW(esh->platformSpecificID);
101         //printf("%s:%d: table %d/%d has platform:specific %d:%d\n", __FILE__, __LINE__, i, nSubtables, platformID, platformSpecificID);
102         switch(platformID) {
103         case 0: // Unicode platform
104           switch(platformSpecificID) {
105           case 0:
106           case 1:
107           case 2:
108           case 3:
109             foundOffset = SWAPL(esh->encodingOffset);
110             foundPlatformID = platformID;
111             foundPlatformSpecificID = platformSpecificID;
112             foundTable = i;
113             found = TRUE;
114             break;
115 
116           default: printf("Error: table %d (psid %d) is unknown. Skipping.\n", i, platformSpecificID); break;
117           }
118           break;
119 
120           //default:
121           //printf("Skipping platform id %d\n", platformID);
122         }
123     }
124 
125 
126     if (found)
127     {
128       subtable = (const CMAPEncodingSubtable *) ((const char *) cmap + foundOffset);
129       //printf("%s:%d: using subtable #%d/%d type %d:%d\n", __FILE__, __LINE__, foundTable, nSubtables, foundPlatformID, foundPlatformSpecificID);
130     } else {
131       printf("%s:%d: could not find subtable.\n", __FILE__, __LINE__);
132       return NULL;
133     }
134 
135     le_uint16 tableFormat = SWAPW(subtable->format);
136     //printf("%s:%d: table format %d\n", __FILE__, __LINE__, tableFormat);
137 
138     switch (tableFormat) {
139     case 4:
140         return new CMAPFormat4Mapper(cmap, (const CMAPFormat4Encoding *) subtable);
141 
142     case 12:
143     {
144         const CMAPFormat12Encoding *encoding = (const CMAPFormat12Encoding *) subtable;
145 
146         return new CMAPGroupMapper(cmap, encoding->groups, SWAPL(encoding->nGroups));
147     }
148 
149     default:
150         break;
151     }
152 
153     printf("%s:%d: Unknown format %x.\n", __FILE__, __LINE__, (SWAPW(subtable->format)));
154     return NULL;
155 }
156 
CMAPFormat4Mapper(const CMAPTable * cmap,const CMAPFormat4Encoding * header)157 CMAPFormat4Mapper::CMAPFormat4Mapper(const CMAPTable *cmap, const CMAPFormat4Encoding *header)
158     : CMAPMapper(cmap)
159 {
160     le_uint16 segCount = SWAPW(header->segCountX2) / 2;
161 
162     fEntrySelector = SWAPW(header->entrySelector);
163     fRangeShift = SWAPW(header->rangeShift) / 2;
164     fEndCodes = &header->endCodes[0];
165     fStartCodes = &header->endCodes[segCount + 1]; // + 1 for reservedPad...
166     fIdDelta = &fStartCodes[segCount];
167     fIdRangeOffset = &fIdDelta[segCount];
168 }
169 
unicodeToGlyph(LEUnicode32 unicode32) const170 LEGlyphID CMAPFormat4Mapper::unicodeToGlyph(LEUnicode32 unicode32) const
171 {
172     if (unicode32 >= 0x10000) {
173         return 0;
174     }
175 
176     LEUnicode16 unicode = (LEUnicode16) unicode32;
177     le_uint16 index = 0;
178     le_uint16 probe = 1 << fEntrySelector;
179     TTGlyphID result = 0;
180 
181     if (SWAPU16(fStartCodes[fRangeShift]) <= unicode) {
182         index = fRangeShift;
183     }
184 
185     while (probe > (1 << 0)) {
186         probe >>= 1;
187 
188         if (SWAPU16(fStartCodes[index + probe]) <= unicode) {
189             index += probe;
190         }
191     }
192 
193     if (unicode >= SWAPU16(fStartCodes[index]) && unicode <= SWAPU16(fEndCodes[index])) {
194         if (fIdRangeOffset[index] == 0) {
195             result = (TTGlyphID) unicode;
196         } else {
197             le_uint16 offset = unicode - SWAPU16(fStartCodes[index]);
198             le_uint16 rangeOffset = SWAPW(fIdRangeOffset[index]);
199             le_uint16 *glyphIndexTable = (le_uint16 *) ((char *) &fIdRangeOffset[index] + rangeOffset);
200 
201             result = SWAPW(glyphIndexTable[offset]);
202         }
203 
204         result += SWAPW(fIdDelta[index]);
205     } else {
206         result = 0;
207     }
208 
209     return LE_SET_GLYPH(0, result);
210 }
211 
~CMAPFormat4Mapper()212 CMAPFormat4Mapper::~CMAPFormat4Mapper()
213 {
214     // parent destructor does it all
215 }
216 
CMAPGroupMapper(const CMAPTable * cmap,const CMAPGroup * groups,le_uint32 nGroups)217 CMAPGroupMapper::CMAPGroupMapper(const CMAPTable *cmap, const CMAPGroup *groups, le_uint32 nGroups)
218     : CMAPMapper(cmap), fGroups(groups)
219 {
220     le_uint8 bit = highBit(nGroups);
221     fPower = 1 << bit;
222     fRangeOffset = nGroups - fPower;
223 }
224 
unicodeToGlyph(LEUnicode32 unicode32) const225 LEGlyphID CMAPGroupMapper::unicodeToGlyph(LEUnicode32 unicode32) const
226 {
227     le_int32 probe = fPower;
228     le_int32 range = 0;
229 
230     if (SWAPU32(fGroups[fRangeOffset].startCharCode) <= unicode32) {
231         range = fRangeOffset;
232     }
233 
234     while (probe > (1 << 0)) {
235         probe >>= 1;
236 
237         if (SWAPU32(fGroups[range + probe].startCharCode) <= unicode32) {
238             range += probe;
239         }
240     }
241 
242     if (SWAPU32(fGroups[range].startCharCode) <= unicode32 && SWAPU32(fGroups[range].endCharCode) >= unicode32) {
243         return (LEGlyphID) (SWAPU32(fGroups[range].startGlyphCode) + unicode32 - SWAPU32(fGroups[range].startCharCode));
244     }
245 
246     return 0;
247 }
248 
~CMAPGroupMapper()249 CMAPGroupMapper::~CMAPGroupMapper()
250 {
251     // parent destructor does it all
252 }
253 
254