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
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
|
/*
This file is part of libextractor.
Copyright (C) 2012 Christian Grothoff
libextractor 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, or (at your
option) any later version.
libextractor 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 libextractor; see the file COPYING. If not, write to the
Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
Boston, MA 02110-1301, USA.
*/
/**
* @file plugins/tiff_extractor.c
* @brief plugin to support TIFF files
* @author Christian Grothoff
*/
#include "platform.h"
#include "extractor.h"
#include <tiffio.h>
/**
* Error handler for libtiff. Does nothing.
*
* @param module where did the error arise?
* @param fmt format string
* @param ap arguments for fmt
*/
static void
error_cb (const char *module,
const char *fmt,
va_list ap)
{
/* do nothing */
}
/**
* Callback invoked by TIFF lib for reading.
*
* @param ctx the 'struct EXTRACTOR_ExtractContext'
* @param data where to write data
* @param size number of bytes to read
* @return number of bytes read
*/
static tsize_t
read_cb (thandle_t ctx,
tdata_t data,
tsize_t size)
{
struct EXTRACTOR_ExtractContext *ec = ctx;
void *ptr;
ssize_t ret;
ret = ec->read (ec->cls, &ptr, size);
if (ret > 0)
memcpy (data, ptr, ret);
return ret;
}
/**
* Callback invoked by TIFF lib for writing. Always fails.
*
* @param ctx the 'struct EXTRACTOR_ExtractContext'
* @param data where to write data
* @param size number of bytes to read
* @return -1 (error)
*/
static tsize_t
write_cb (thandle_t ctx,
tdata_t data,
tsize_t size)
{
return -1;
}
/**
* Callback invoked by TIFF lib for seeking.
*
* @param ctx the 'struct EXTRACTOR_ExtractContext'
* @param offset target offset
* @param whence target is relative to where
* @return new offset
*/
static toff_t
seek_cb (thandle_t ctx,
toff_t offset,
int whence)
{
struct EXTRACTOR_ExtractContext *ec = ctx;
return ec->seek (ec->cls, offset, whence);
}
/**
* Callback invoked by TIFF lib for getting the file size.
*
* @param ctx the 'struct EXTRACTOR_ExtractContext'
* @return file size
*/
static toff_t
size_cb (thandle_t ctx)
{
struct EXTRACTOR_ExtractContext *ec = ctx;
return ec->get_size (ec->cls);
}
/**
* Callback invoked by TIFF lib for closing the file. Does nothing.
*
* @param ctx the 'struct EXTRACTOR_ExtractContext'
*/
static int
close_cb (thandle_t ctx)
{
return 0; /* success */
}
/**
* A mapping from TIFF Tag to extractor types.
*/
struct Matches
{
/**
* TIFF Tag.
*/
ttag_t tag;
/**
* Corresponding LE type.
*/
enum EXTRACTOR_MetaType type;
};
/**
* Mapping of TIFF tags to LE types.
* NULL-terminated.
*/
static struct Matches tmap[] = {
{ TIFFTAG_ARTIST, EXTRACTOR_METATYPE_ARTIST },
{ TIFFTAG_COPYRIGHT, EXTRACTOR_METATYPE_COPYRIGHT },
{ TIFFTAG_DATETIME, EXTRACTOR_METATYPE_CREATION_DATE },
{ TIFFTAG_DOCUMENTNAME, EXTRACTOR_METATYPE_TITLE },
{ TIFFTAG_HOSTCOMPUTER, EXTRACTOR_METATYPE_BUILDHOST },
{ TIFFTAG_IMAGEDESCRIPTION, EXTRACTOR_METATYPE_DESCRIPTION },
{ TIFFTAG_MAKE, EXTRACTOR_METATYPE_CAMERA_MAKE },
{ TIFFTAG_MODEL, EXTRACTOR_METATYPE_CAMERA_MODEL },
{ TIFFTAG_PAGENAME, EXTRACTOR_METATYPE_PAGE_RANGE },
{ TIFFTAG_SOFTWARE, EXTRACTOR_METATYPE_CREATED_BY_SOFTWARE },
{ TIFFTAG_TARGETPRINTER, EXTRACTOR_METATYPE_TARGET_ARCHITECTURE },
{ 0, 0 }
};
/**
* Main entry method for the 'image/tiff' extraction plugin.
*
* @param ec extraction context provided to the plugin
*/
void
EXTRACTOR_tiff_extract_method (struct EXTRACTOR_ExtractContext *ec)
{
TIFF *tiff;
unsigned int i;
char *meta;
char format[128];
uint32_t width;
uint32_t height;
TIFFSetErrorHandler (&error_cb);
TIFFSetWarningHandler (&error_cb);
tiff = TIFFClientOpen ("<no filename>",
"rm", /* read-only, no mmap */
ec,
&read_cb,
&write_cb,
&seek_cb,
&close_cb,
&size_cb,
NULL, NULL);
if (NULL == tiff)
return;
for (i = 0; 0 != tmap[i].tag; i++)
if ( (1 ==
TIFFGetField (tiff, tmap[i].tag, &meta)) &&
(0 !=
ec->proc (ec->cls,
"tiff",
tmap[i].type,
EXTRACTOR_METAFORMAT_UTF8,
"text/plain",
meta,
strlen (meta) + 1)) )
goto CLEANUP;
if ( (1 ==
TIFFGetField (tiff, TIFFTAG_IMAGEWIDTH, &width)) &&
(1 ==
TIFFGetField (tiff, TIFFTAG_IMAGELENGTH, &height)) )
{
snprintf (format,
sizeof (format),
"%ux%u",
(unsigned int) width,
(unsigned int) height);
if (0 !=
ec->proc (ec->cls,
"tiff",
EXTRACTOR_METATYPE_IMAGE_DIMENSIONS,
EXTRACTOR_METAFORMAT_UTF8,
"text/plain",
format,
strlen (format) + 1))
goto CLEANUP;
if (0 !=
ec->proc (ec->cls,
"tiff",
EXTRACTOR_METATYPE_MIMETYPE,
EXTRACTOR_METAFORMAT_UTF8,
"text/plain",
"image/tiff",
strlen ("image/tiff") + 1))
goto CLEANUP;
}
CLEANUP:
TIFFClose (tiff);
}
/* end of tiff_extractor.c */
|
