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
|
#!/usr/bin/perl
# Licensed under GPL v2 or greater
# (c) 2007 Patrick Winnertz <patrick.winnertz@skolelinux.org>
package IkiWiki::Plugin::teximg;
use warnings;
use strict;
use Digest::MD5 qw(md5_hex);
use File::Temp qw(tempdir);
use HTML::Entities;
use IkiWiki 2.00;
sub import { #{{{
hook(type => "preprocess", id => "teximg", call => \&preprocess);
} #}}}
sub preprocess (@) { #{{{
my %params = @_;
my $height = $params{height};
if (! defined $height || ! length $height) {
$height = 12;
}
else {
$height =~ s#(\d+)#$1#;
}
my $code = $params{code};
if (! defined $code && ! length $code) {
return "[[teximg ".gettext("missing tex code"). "]]";
}
if (check($code)) {
return create($code, check_height($height), \%params);
}
else {
return "[[teximg ".gettext("code includes disallowed latex commands"). "]]";
}
} #}}}
sub check_height ($) { #{{{
# Since latex doesn't support unlimited scaling this function
# returns the closest supported size.
my $height =shift;
my @allowed=(8,9,10,11,12,14,17,20);
my $ret;
my $fit;
foreach my $val (@allowed) {
my $f = abs($val - $height);
if (! defined($fit) || $f < $fit ) {
$ret=$val;
$fit=$f;
}
}
return $ret;
} #}}}
sub create ($$$) { #{{{
# This function calls the image generating function and returns
# the <img .. /> for the generated image.
my $code = shift;
my $height = shift;
my $params = shift;
if (! defined($height) and not length($height) ) {
$height = 12;
}
my $digest = md5_hex($code, $height);
my $imglink= $params->{destpage} . "/$digest.png";
my $imglog = $params->{destpage} . "/$digest.log";
will_render($params->{destpage}, $imglink);
will_render($params->{destpage}, $imglog);
my $imgurl=urlto($imglink, $params->{destpage});
my $logurl=urlto($imglink, $params->{destpage});
if (-e "$config{destdir}/$imglink" ||
gen_image($code, $height, $digest, $params->{page})) {
return qq{<img src="$imgurl" alt="}
.(exists $params->{alt} ? $params->{alt} : encode_entities($code))
.qq{" class="teximg" />};
}
else {
return qq{[[teximg <a href="$logurl">}.gettext("failed to generate image from code")."</a>]]";
}
} #}}}
sub gen_image ($$$$) { #{{{
# Actually creates the image.
my $code = shift;
my $height = shift;
my $digest = shift;
my $imagedir = shift;
#TODO This should move into the setup file.
my $tex = '\documentclass['.$height.'pt]{scrartcl}';
$tex .= '\usepackage[version=3]{mhchem}';
$tex .= '\usepackage{amsmath}';
$tex .= '\usepackage{amsfonts}';
$tex .= '\usepackage{amssymb}';
$tex .= '\pagestyle{empty}';
$tex .= '\begin{document}';
$tex .= '$$'.$code.'$$';
$tex .= '\end{document}';
my $tmp = eval { create_tmp_dir($digest) };
if (! $@ &&
writefile("$digest.tex", $tmp, $tex) &&
system("cd $tmp; latex --interaction=nonstopmode $tmp/$digest.tex > /dev/null") == 0 &&
system("dvips -E $tmp/$digest.dvi -o $tmp/$digest.ps 2> $tmp/$digest.log") == 0 &&
# ensure destination directory exists
writefile("$imagedir/$digest.png", $config{destdir}, "") &&
system("convert -density 120 -trim -transparent \"#FFFFFF\" $tmp/$digest.ps $config{destdir}/$imagedir/$digest.png > $tmp/$digest.log") == 0) {
return 1;
}
else {
# store failure log
my $log;
{
open(my $f, '<', "$tmp/$digest.log");
local $/=undef;
$log = <$f>;
close($f);
}
writefile("$digest.log", "$config{destdir}/$imagedir", $log);
return 0;
}
} #}}}
sub create_tmp_dir ($) { #{{{
# Create a temp directory, it will be removed when ikiwiki exits.
my $base = shift;
my $template = $base.".XXXXXXXXXX";
my $tmpdir = tempdir($template, TMPDIR => 1, CLEANUP => 1);
return $tmpdir;
} #}}}
sub check ($) { #{{{
# Check if the code is ok
my $code = shift;
my @badthings = (
qr/\$\$/,
qr/\\include/,
qr/\\includegraphic/,
qr/\\usepackage/,
qr/\\newcommand/,
qr/\\renewcommand/,
qr/\\def/,
qr/\\input/,
qr/\\open/,
qr/\\loop/,
qr/\\errorstopmode/,
qr/\\scrollmode/,
qr/\\batchmode/,
qr/\\read/,
qr/\\write/,
);
foreach my $thing (@badthings) {
if ($code =~ m/$thing/ ) {
return 0;
}
}
return 1;
} #}}}
1
|