1 // -*- related-file-name: "../include/efont/ttfkern.hh" -*-
2
3 /* ttfkern.{cc,hh} -- TrueType kern table
4 *
5 * Copyright (c) 2009-2019 Eddie Kohler
6 *
7 * This program is free software; you can redistribute it and/or modify it
8 * under the terms of the GNU General Public License as published by the Free
9 * Software Foundation; either version 2 of the License, or (at your option)
10 * any later version. This program is distributed in the hope that it will be
11 * useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
13 * Public License for more details.
14 */
15
16 #ifdef HAVE_CONFIG_H
17 # include <config.h>
18 #endif
19 #include <efont/ttfkern.hh>
20 #include <lcdf/error.hh>
21 #include <lcdf/straccum.hh>
22 #include <errno.h>
23 #include <stdlib.h>
24 #include <string.h>
25 #include <algorithm>
26
27 namespace Efont { namespace OpenType {
28
29 inline Data
subtable(uint32_t & off_in_out) const30 KernTable::subtable(uint32_t &off_in_out) const
31 {
32 uint32_t off = off_in_out, len;
33 if (_version == 0) {
34 if (_d.u16(off) != 0)
35 throw new Format("kern subtable");
36 len = _d.u16(off + 2);
37 } else
38 len = _d.u32(off);
39 if (len < 6 || off + len > (uint32_t) _d.length())
40 throw new Bounds();
41 off_in_out = off + len;
42 return _d.substring(off, len);
43 }
44
KernTable(const Data & d,ErrorHandler *)45 KernTable::KernTable(const Data &d, ErrorHandler *)
46 : _d(d), _error(-1)
47 {
48 // USHORT Version
49 // USHORT nTables
50 if (d.length() == 0)
51 throw BlankTable("kern");
52
53 uint32_t ntables, off;
54 if (d.u16(0) == 0) {
55 ntables = d.u16(2);
56 _version = 0;
57 off = 4;
58 } else if (d.u16(0) == 1) {
59 ntables = d.u32(4);
60 _version = 1;
61 off = 8;
62 } else
63 throw Format("kern");
64
65 for (uint32_t i = 0; i < ntables; ++i)
66 (void) subtable(off);
67
68 _error = 0;
69 }
70
71 bool
unparse_automatics(Vector<Positioning> & v,ErrorHandler * errh) const72 KernTable::unparse_automatics(Vector<Positioning> &v, ErrorHandler *errh) const
73 {
74 uint32_t ntables = this->ntables();
75 uint32_t off = first_offset();
76 int success = 0;
77 if (_error < 0)
78 return false;
79
80 for (uint16_t i = 0; i < ntables; ++i) {
81 Data subt = _d.subtable(off);
82 uint16_t coverage = subt.u16(4);
83
84 if (_version == 0) {
85 if ((coverage & COV_V0_HORIZONTAL) == 0
86 || (coverage & (COV_V0_MINIMUM | COV_V0_CROSS_STREAM
87 | COV_V0_OVERRIDE)) != 0
88 || (coverage & COV_V0_FORMAT) != COV_V0_FORMAT0)
89 continue;
90 } else {
91 if ((coverage & (COV_V1_VERTICAL | COV_V1_CROSS_STREAM
92 | COV_V1_VARIATION)) != 0
93 || (coverage & COV_V1_FORMAT) != COV_V1_FORMAT0)
94 continue;
95 }
96
97 try {
98 uint32_t off = (_version ? 16 : 14);
99 uint16_t npairs = subt.u16(off - 8);
100 for (uint16_t j = 0; j < npairs; ++j, off += 6) {
101 v.push_back(Positioning(Position(subt.u16(off), 0, 0, subt.s16(off + 4), 0),
102 Position(subt.u16(off + 2), 0, 0, 0, 0)));
103 ++success;
104 }
105 } catch (Error e) {
106 if (errh)
107 errh->warning("%s, continuing", e.description.c_str());
108 }
109 }
110
111 return success > 0;
112 }
113
114 }}
115
116 #include <lcdf/vector.cc>
117