1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
|
/*************************************************************************
** VFReader.cpp **
** **
** This file is part of dvisvgm -- a fast DVI to SVG converter **
** Copyright (C) 2005-2019 Martin Gieseking <martin.gieseking@uos.de> **
** **
** This program is free software; you can redistribute it and/or **
** modify it under the terms of the GNU General Public License as **
** published by the Free Software Foundation; either version 3 of **
** the License, or (at your option) any later version. **
** **
** This program is distributed in the hope that it will be useful, but **
** WITHOUT ANY WARRANTY; without even the implied warranty of **
** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the **
** GNU General Public License for more details. **
** **
** You should have received a copy of the GNU General Public License **
** along with this program; if not, see <http://www.gnu.org/licenses/>. **
*************************************************************************/
#include <sstream>
#include "FixWord.hpp"
#include "Font.hpp"
#include "Length.hpp"
#include "VFActions.hpp"
#include "VFReader.hpp"
using namespace std;
VFReader::VFReader (istream &is) : StreamReader(is)
{
}
VFActions* VFReader::replaceActions (VFActions *a) {
VFActions *ret = _actions;
_actions = a;
return ret;
}
/** Reads a single VF command from the current position of the input stream and calls the
* corresponding cmdFOO method. The execution can be influenced by a function of type ApproveOpcode.
* It takes an opcode and returns true if the command is supposed to be executed.
* @param[in] approve function to approve invocation of the action assigned to command
* @return opcode of the executed command */
int VFReader::executeCommand (ApproveAction approve) {
int opcode = readByte();
if (!isStreamValid() || opcode < 0) // at end of file?
throw VFException("invalid VF file");
bool approved = !approve || approve(opcode);
VFActions *actions = _actions;
if (!approved)
replaceActions(nullptr); // disable actions
if (opcode <= 241) // short character definition?
cmdShortChar(opcode);
else if (opcode >= 243 && opcode <= 246) // font definition?
cmdFontDef(opcode-243+1);
else {
switch (opcode) {
case 242: cmdLongChar(); break; // long character definition
case 247: cmdPre(); break; // preamble
case 248: cmdPost(); break; // postamble
default : { // invalid opcode
replaceActions(actions); // reenable actions
ostringstream oss;
oss << "undefined VF command (opcode " << opcode << ')';
throw VFException(oss.str());
}
}
}
replaceActions(actions); // reenable actions
return opcode;
}
bool VFReader::executeAll () {
clearStream(); // reset all status bits
if (!isStreamValid())
return false;
seek(0); // move file pointer to first byte of the input stream
while (!eof() && executeCommand() != 248); // stop reading after post (248)
return true;
}
bool VFReader::executePreambleAndFontDefs () {
clearStream();
if (!isStreamValid())
return false;
seek(0); // move file pointer to first byte of the input stream
auto is_pre_or_fontdef = [](int op) {return op > 242;};
while (!eof() && executeCommand(is_pre_or_fontdef) > 242); // stop reading after last font definition
return true;
}
bool VFReader::executeCharDefs () {
clearStream();
if (!isStreamValid())
return false;
seek(0);
auto is_chardef = [](int op) {return op < 243;};
while (!eof() && executeCommand(is_chardef) < 243); // stop reading after last char definition
return true;
}
//////////////////////////////////////////////////////////////////////////////
/** Reads and executes DVI preamble command. */
void VFReader::cmdPre () {
uint32_t i = readUnsigned(1); // identification number (should be 2)
uint32_t k = readUnsigned(1); // length of following comment
string cmt = readString(k); // comment
uint32_t cs = readUnsigned(4); // check sum to be compared with TFM cecksum
int32_t ds = readUnsigned(4); // design size (same as TFM design size) (fix_word)
_designSize = double(FixWord(ds))*Length::pt2bp;
if (i != 202)
throw VFException("invalid identification value in preamble");
if (_actions)
_actions->vfPreamble(cmt, cs, ds);
}
void VFReader::cmdPost () {
while ((readUnsigned(1)) == 248); // skip fill bytes
if (_actions)
_actions->vfPostamble();
}
void VFReader::cmdLongChar () {
uint32_t pl = readUnsigned(4); // packet length (length of DVI subroutine)
if (!_actions)
seek(8+pl, ios::cur); // skip remaining char definition bytes
else {
uint32_t cc = readUnsigned(4); // character code
readUnsigned(4); // equals character width from corresponding TFM file
vector<uint8_t> dvi(pl); // DVI subroutine
readBytes(pl, dvi);
_actions->defineVFChar(cc, std::move(dvi)); // call template method for user actions
}
}
/** Reads and executes short_char_x command.
* @param[in] pl packet length (length of DVI subroutine) */
void VFReader::cmdShortChar (int pl) {
if (!_actions)
seek(4+pl, ios::cur); // skip char definition bytes
else {
uint32_t cc = readUnsigned(1); // character code
readUnsigned(3); // character width from corresponding TFM file
vector<uint8_t> dvi(pl); // DVI subroutine
readBytes(pl, dvi);
_actions->defineVFChar(cc, std::move(dvi)); // call template method for user actions
}
}
void VFReader::cmdFontDef (int len) {
uint32_t fontnum = readUnsigned(len); // font number
uint32_t checksum = readUnsigned(4); // font checksum (to be compared with corresponding TFM checksum)
uint32_t ssize = readUnsigned(4); // scaled size of font relative to design size (fix_word)
uint32_t dsize = readUnsigned(4); // design size of font (same as TFM design size) (fix_word)
uint32_t pathlen = readUnsigned(1); // length of font path
uint32_t namelen = readUnsigned(1); // length of font name
string fontpath = readString(pathlen);
string fontname = readString(namelen);
if (_actions) {
double ss = double(FixWord(ssize))*Length::pt2bp;
double ds = double(FixWord(dsize))*Length::pt2bp;
_actions->defineVFFont(fontnum, fontpath, fontname, checksum, ds, ss*_designSize);
}
}
|
