1 /***************************************************************************
2 *
3 *   Copyright (C) 1998-2013, International Business Machines
4 *   Corporation and others.  All Rights Reserved.
5 *
6 ************************************************************************/
7 
8 #include "layout/LETypes.h"
9 #include "layout/LESwaps.h"
10 
11 #include "sfnt.h"
12 #include "cmaps.h"
13 #include <stdio.h>
14 
15 #define SWAPU16(code) ((LEUnicode16) SWAPW(code))
16 #define SWAPU32(code) ((LEUnicode32) SWAPL(code))
17 
18 //
19 // Finds the high bit by binary searching
20 // through the bits in value.
21 //
highBit(le_uint32 value)22 le_int8 highBit(le_uint32 value)
23 {
24     le_uint8 bit = 0;
25 
26     if (value >= 1 << 16) {
27         value >>= 16;
28         bit += 16;
29     }
30 
31     if (value >= 1 << 8) {
32         value >>= 8;
33         bit += 8;
34     }
35 
36     if (value >= 1 << 4) {
37         value >>= 4;
38         bit += 4;
39     }
40 
41     if (value >= 1 << 2) {
42         value >>= 2;
43         bit += 2;
44     }
45 
46     if (value >= 1 << 1) {
47         value >>= 1;
48         bit += 1;
49     }
50 
51     return bit;
52 }
53 
createUnicodeMapper(const CMAPTable * cmap)54 CMAPMapper *CMAPMapper::createUnicodeMapper(const CMAPTable *cmap)
55 {
56     le_uint16 i;
57     le_uint16 nSubtables = SWAPW(cmap->numberSubtables);
58     const CMAPEncodingSubtable *subtable = NULL;
59     le_bool found = FALSE;
60     le_uint16 foundPlatformID = 0xFFFF;
61     le_uint16 foundPlatformSpecificID = 0xFFFF;
62     le_uint32 foundOffset = 0;
63     le_uint16 foundTable = 0xFFFF;
64     // first pass, look for MS table. (preferred?)
65     for (i = 0; i < nSubtables && !found; i += 1) {
66         const CMAPEncodingSubtableHeader *esh = &cmap->encodingSubtableHeaders[i];
67 
68         le_uint16 platformID = SWAPW(esh->platformID);
69         le_uint16 platformSpecificID = SWAPW(esh->platformSpecificID);
70         if (platformID == 3) { // microsoft
71           switch (platformSpecificID) {
72             case 1: // Unicode BMP (UCS-2)
73             case 10: // Unicode UCS-4
74                 foundOffset = SWAPL(esh->encodingOffset);
75                 foundPlatformID = platformID;
76                 foundPlatformSpecificID = platformSpecificID;
77                 found = TRUE;
78                 foundTable = i;
79                 break;
80 
81                 //default:
82               //              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);
83             }
84         } else {
85           //printf("%s:%d: platform  ID %d (wanted 3, microsoft) for subtable %d/%d\n", __FILE__, __LINE__, (SWAPW(esh->platformID)), i, nSubtables);
86         }
87     }
88 
89     // second pass, allow non MS table
90     // first pass, look for MS table. (preferred?)
91       for (i = 0; i < nSubtables && !found; i += 1) {
92         const CMAPEncodingSubtableHeader *esh = &cmap->encodingSubtableHeaders[i];
93         le_uint16 platformID = SWAPW(esh->platformID);
94         le_uint16 platformSpecificID = SWAPW(esh->platformSpecificID);
95         //printf("%s:%d: table %d/%d has platform:specific %d:%d\n", __FILE__, __LINE__, i, nSubtables, platformID, platformSpecificID);
96         switch(platformID) {
97         case 0: // Unicode platform
98           switch(platformSpecificID) {
99           case 0:
100           case 1:
101           case 2:
102           case 3:
103             foundOffset = SWAPL(esh->encodingOffset);
104             foundPlatformID = platformID;
105             foundPlatformSpecificID = platformSpecificID;
106             foundTable = i;
107             found = TRUE;
108             break;
109 
110           default: printf("Error: table %d (psid %d) is unknown. Skipping.\n", i, platformSpecificID); break;
111           }
112           break;
113 
114           //default:
115           //printf("Skipping platform id %d\n", platformID);
116         }
117     }
118 
119 
120     if (found)
121     {
122       subtable = (const CMAPEncodingSubtable *) ((const char *) cmap + foundOffset);
123       //printf("%s:%d: using subtable #%d/%d type %d:%d\n", __FILE__, __LINE__, foundTable, nSubtables, foundPlatformID, foundPlatformSpecificID);
124     } else {
125       printf("%s:%d: could not find subtable.\n", __FILE__, __LINE__);
126       return NULL;
127     }
128 
129     le_uint16 tableFormat = SWAPW(subtable->format);
130     //printf("%s:%d: table format %d\n", __FILE__, __LINE__, tableFormat);
131 
132     switch (tableFormat) {
133     case 4:
134         return new CMAPFormat4Mapper(cmap, (const CMAPFormat4Encoding *) subtable);
135 
136     case 12:
137     {
138         const CMAPFormat12Encoding *encoding = (const CMAPFormat12Encoding *) subtable;
139 
140         return new CMAPGroupMapper(cmap, encoding->groups, SWAPL(encoding->nGroups));
141     }
142 
143     default:
144         break;
145     }
146 
147     printf("%s:%d: Unknown format %x.\n", __FILE__, __LINE__, (SWAPW(subtable->format)));
148     return NULL;
149 }
150 
CMAPFormat4Mapper(const CMAPTable * cmap,const CMAPFormat4Encoding * header)151 CMAPFormat4Mapper::CMAPFormat4Mapper(const CMAPTable *cmap, const CMAPFormat4Encoding *header)
152     : CMAPMapper(cmap)
153 {
154     le_uint16 segCount = SWAPW(header->segCountX2) / 2;
155 
156     fEntrySelector = SWAPW(header->entrySelector);
157     fRangeShift = SWAPW(header->rangeShift) / 2;
158     fEndCodes = &header->endCodes[0];
159     fStartCodes = &header->endCodes[segCount + 1]; // + 1 for reservedPad...
160     fIdDelta = &fStartCodes[segCount];
161     fIdRangeOffset = &fIdDelta[segCount];
162 }
163 
unicodeToGlyph(LEUnicode32 unicode32) const164 LEGlyphID CMAPFormat4Mapper::unicodeToGlyph(LEUnicode32 unicode32) const
165 {
166     if (unicode32 >= 0x10000) {
167         return 0;
168     }
169 
170     LEUnicode16 unicode = (LEUnicode16) unicode32;
171     le_uint16 index = 0;
172     le_uint16 probe = 1 << fEntrySelector;
173     TTGlyphID result = 0;
174 
175     if (SWAPU16(fStartCodes[fRangeShift]) <= unicode) {
176         index = fRangeShift;
177     }
178 
179     while (probe > (1 << 0)) {
180         probe >>= 1;
181 
182         if (SWAPU16(fStartCodes[index + probe]) <= unicode) {
183             index += probe;
184         }
185     }
186 
187     if (unicode >= SWAPU16(fStartCodes[index]) && unicode <= SWAPU16(fEndCodes[index])) {
188         if (fIdRangeOffset[index] == 0) {
189             result = (TTGlyphID) unicode;
190         } else {
191             le_uint16 offset = unicode - SWAPU16(fStartCodes[index]);
192             le_uint16 rangeOffset = SWAPW(fIdRangeOffset[index]);
193             le_uint16 *glyphIndexTable = (le_uint16 *) ((char *) &fIdRangeOffset[index] + rangeOffset);
194 
195             result = SWAPW(glyphIndexTable[offset]);
196         }
197 
198         result += SWAPW(fIdDelta[index]);
199     } else {
200         result = 0;
201     }
202 
203     return LE_SET_GLYPH(0, result);
204 }
205 
~CMAPFormat4Mapper()206 CMAPFormat4Mapper::~CMAPFormat4Mapper()
207 {
208     // parent destructor does it all
209 }
210 
CMAPGroupMapper(const CMAPTable * cmap,const CMAPGroup * groups,le_uint32 nGroups)211 CMAPGroupMapper::CMAPGroupMapper(const CMAPTable *cmap, const CMAPGroup *groups, le_uint32 nGroups)
212     : CMAPMapper(cmap), fGroups(groups)
213 {
214     le_uint8 bit = highBit(nGroups);
215     fPower = 1 << bit;
216     fRangeOffset = nGroups - fPower;
217 }
218 
unicodeToGlyph(LEUnicode32 unicode32) const219 LEGlyphID CMAPGroupMapper::unicodeToGlyph(LEUnicode32 unicode32) const
220 {
221     le_int32 probe = fPower;
222     le_int32 range = 0;
223 
224     if (SWAPU32(fGroups[fRangeOffset].startCharCode) <= unicode32) {
225         range = fRangeOffset;
226     }
227 
228     while (probe > (1 << 0)) {
229         probe >>= 1;
230 
231         if (SWAPU32(fGroups[range + probe].startCharCode) <= unicode32) {
232             range += probe;
233         }
234     }
235 
236     if (SWAPU32(fGroups[range].startCharCode) <= unicode32 && SWAPU32(fGroups[range].endCharCode) >= unicode32) {
237         return (LEGlyphID) (SWAPU32(fGroups[range].startGlyphCode) + unicode32 - SWAPU32(fGroups[range].startCharCode));
238     }
239 
240     return 0;
241 }
242 
~CMAPGroupMapper()243 CMAPGroupMapper::~CMAPGroupMapper()
244 {
245     // parent destructor does it all
246 }
247 
248