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//
22le_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
54CMAPMapper *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
151CMAPFormat4Mapper::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
164LEGlyphID 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
206CMAPFormat4Mapper::~CMAPFormat4Mapper()
207{
208    // parent destructor does it all
209}
210
211CMAPGroupMapper::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
219LEGlyphID 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
243CMAPGroupMapper::~CMAPGroupMapper()
244{
245    // parent destructor does it all
246}
247
248