1// SPDX-License-Identifier: MIT OR MPL-2.0 OR LGPL-2.1-or-later OR GPL-2.0-or-later
2// Copyright 2010, SIL International, All rights reserved.
3
4
5#include "inc/Main.h"
6#include "inc/CmapCache.h"
7#include "inc/Face.h"
8#include "inc/TtfTypes.h"
9#include "inc/TtfUtil.h"
10
11
12using namespace graphite2;
13
14const void * bmp_subtable(const Face::Table & cmap)
15{
16 const void * stbl;
17 if (!cmap.size()) return 0;
18 if (TtfUtil::CheckCmapSubtable4(stbl = TtfUtil::FindCmapSubtable(cmap, 3, 1, cmap.size()), cmap + cmap.size())
19 || TtfUtil::CheckCmapSubtable4(stbl = TtfUtil::FindCmapSubtable(cmap, 0, 3, cmap.size()), cmap + cmap.size())
20 || TtfUtil::CheckCmapSubtable4(stbl = TtfUtil::FindCmapSubtable(cmap, 0, 2, cmap.size()), cmap + cmap.size())
21 || TtfUtil::CheckCmapSubtable4(stbl = TtfUtil::FindCmapSubtable(cmap, 0, 1, cmap.size()), cmap + cmap.size())
22 || TtfUtil::CheckCmapSubtable4(stbl = TtfUtil::FindCmapSubtable(cmap, 0, 0, cmap.size()), cmap + cmap.size()))
23 return stbl;
24 return 0;
25}
26
27const void * smp_subtable(const Face::Table & cmap)
28{
29 const void * stbl;
30 if (!cmap.size()) return 0;
31 if (TtfUtil::CheckCmapSubtable12(stbl = TtfUtil::FindCmapSubtable(cmap, 3, 10, cmap.size()), cmap + cmap.size())
32 || TtfUtil::CheckCmapSubtable12(stbl = TtfUtil::FindCmapSubtable(cmap, 0, 4, cmap.size()), cmap + cmap.size()))
33 return stbl;
34 return 0;
35}
36
37template <unsigned int (*NextCodePoint)(const void *, unsigned int, int *),
38 uint16 (*LookupCodePoint)(const void *, unsigned int, int)>
39bool cache_subtable(uint16 * blocks[], const void * cst, const unsigned int limit)
40{
41 int rangeKey = 0;
42 uint32 codePoint = NextCodePoint(cst, 0, &rangeKey),
43 prevCodePoint = 0;
44 while (codePoint < limit)
45 {
46 unsigned int block = codePoint >> 8;
47 if (!blocks[block])
48 {
49 blocks[block] = grzeroalloc<uint16>(0x100);
50 if (!blocks[block])
51 return false;
52 }
53 blocks[block][codePoint & 0xFF] = LookupCodePoint(cst, codePoint, rangeKey);
54 // prevent infinite loop
55 if (codePoint <= prevCodePoint)
56 codePoint = prevCodePoint + 1;
57 prevCodePoint = codePoint;
58 codePoint = NextCodePoint(cst, codePoint, &rangeKey);
59 }
60 return true;
61}
62
63
64CachedCmap::CachedCmap(const Face & face)
65: m_isBmpOnly(true),
66 m_blocks(0)
67{
68 const Face::Table cmap(face, Tag::cmap);
69 if (!cmap) return;
70
71 const void * bmp_cmap = bmp_subtable(cmap);
72 const void * smp_cmap = smp_subtable(cmap);
73 m_isBmpOnly = !smp_cmap;
74
75 m_blocks = grzeroalloc<uint16 *>(m_isBmpOnly ? 0x100 : 0x1100);
76 if (m_blocks && smp_cmap)
77 {
78 if (!cache_subtable<TtfUtil::CmapSubtable12NextCodepoint, TtfUtil::CmapSubtable12Lookup>(m_blocks, smp_cmap, 0x10FFFF))
79 return;
80 }
81
82 if (m_blocks && bmp_cmap)
83 {
84 if (!cache_subtable<TtfUtil::CmapSubtable4NextCodepoint, TtfUtil::CmapSubtable4Lookup>(m_blocks, bmp_cmap, 0xFFFF))
85 return;
86 }
87}
88
89CachedCmap::~CachedCmap() throw()
90{
91 if (!m_blocks) return;
92 unsigned int numBlocks = (m_isBmpOnly)? 0x100 : 0x1100;
93 for (unsigned int i = 0; i < numBlocks; i++)
94 free(m_blocks[i]);
95 free(m_blocks);
96}
97
98uint16 CachedCmap::operator [] (const uint32 usv) const throw()
99{
100 if ((m_isBmpOnly && usv > 0xFFFF) || (usv > 0x10FFFF))
101 return 0;
102 const uint32 block = 0xFFFF & (usv >> 8);
103 if (m_blocks[block])
104 return m_blocks[block][usv & 0xFF];
105 return 0;
106};
107
108CachedCmap::operator bool() const throw()
109{
110 return m_blocks != 0;
111}
112
113
114DirectCmap::DirectCmap(const Face & face)
115: _cmap(face, Tag::cmap),
116 _smp(smp_subtable(_cmap)),
117 _bmp(bmp_subtable(_cmap))
118{
119}
120
121uint16 DirectCmap::operator [] (const uint32 usv) const throw()
122{
123 return usv > 0xFFFF
124 ? (_smp ? TtfUtil::CmapSubtable12Lookup(_smp, usv, 0) : 0)
125 : TtfUtil::CmapSubtable4Lookup(_bmp, usv, 0);
126}
127
128DirectCmap::operator bool () const throw()
129{
130 return _cmap && _bmp;
131}
132
133