1/* exif-mnote-data-olympus.c
2 *
3 * Copyright (c) 2002, 2003 Lutz Mueller <lutz@users.sourceforge.net>
4 *
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Lesser General Public
7 * License as published by the Free Software Foundation; either
8 * version 2 of the License, or (at your option) any later version.
9 *
10 * This library is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13 * Lesser General Public License for more details.
14 *
15 * You should have received a copy of the GNU Lesser General Public
16 * License along with this library; if not, write to the
17 * Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
18 * Boston, MA  02110-1301  USA.
19 */
20
21#include <config.h>
22#include "exif-mnote-data-olympus.h"
23
24#include <stdlib.h>
25#include <string.h>
26#include <stdio.h>
27
28#include <libexif/exif-utils.h>
29#include <libexif/exif-data.h>
30
31#define DEBUG
32
33/* Uncomment this to fix a problem with Sanyo MakerNotes. It's probably best
34 * not to in most cases because it seems to only affect the thumbnail tag
35 * which is duplicated in IFD 1, and fixing the offset could actually cause
36 * problems with other software that expects the broken form.
37 */
38/*#define EXIF_OVERCOME_SANYO_OFFSET_BUG */
39
40static enum OlympusVersion
41exif_mnote_data_olympus_identify_variant (const unsigned char *buf,
42		unsigned int buf_size);
43
44
45static void
46exif_mnote_data_olympus_clear (ExifMnoteDataOlympus *n)
47{
48	ExifMnoteData *d = (ExifMnoteData *) n;
49	unsigned int i;
50
51	if (!n) return;
52
53	if (n->entries) {
54		for (i = 0; i < n->count; i++)
55			if (n->entries[i].data) {
56				exif_mem_free (d->mem, n->entries[i].data);
57				n->entries[i].data = NULL;
58			}
59		exif_mem_free (d->mem, n->entries);
60		n->entries = NULL;
61		n->count = 0;
62	}
63}
64
65static void
66exif_mnote_data_olympus_free (ExifMnoteData *n)
67{
68	if (!n) return;
69
70	exif_mnote_data_olympus_clear ((ExifMnoteDataOlympus *) n);
71}
72
73static char *
74exif_mnote_data_olympus_get_value (ExifMnoteData *d, unsigned int i, char *val, unsigned int maxlen)
75{
76	ExifMnoteDataOlympus *n = (ExifMnoteDataOlympus *) d;
77
78	if (!d || !val) return NULL;
79	if (i > n->count -1) return NULL;
80/*
81	exif_log (d->log, EXIF_LOG_CODE_DEBUG, "ExifMnoteDataOlympus",
82		  "Querying value for tag '%s'...",
83		  mnote_olympus_tag_get_name (n->entries[i].tag));
84*/
85	return mnote_olympus_entry_get_value (&n->entries[i], val, maxlen);
86}
87
88
89
90
91/**
92 * @brief save the MnoteData from ne to buf
93 *
94 * @param ne extract the data from this structure
95 * @param *buf write the mnoteData to this buffer (buffer will be allocated)
96 * @param buf_size the size of the buffer
97 */
98static void
99exif_mnote_data_olympus_save (ExifMnoteData *ne,
100		unsigned char **buf, unsigned int *buf_size)
101{
102	ExifMnoteDataOlympus *n = (ExifMnoteDataOlympus *) ne;
103	size_t i, o, s, doff, base = 0, o2 = 6 + 2;
104	size_t datao = 0;
105	unsigned char *t;
106	size_t ts;
107
108	if (!n || !buf || !buf_size) return;
109
110	/*
111	 * Allocate enough memory for all entries and the number of entries.
112	 */
113	*buf_size = 6 + 2 + 2 + n->count * 12;
114	switch (n->version) {
115	case olympusV1:
116	case sanyoV1:
117	case epsonV1:
118		*buf = exif_mem_alloc (ne->mem, *buf_size);
119		if (!*buf) {
120			EXIF_LOG_NO_MEMORY(ne->log, "ExifMnoteDataOlympus", *buf_size);
121			return;
122		}
123
124		/* Write the header and the number of entries. */
125		strcpy ((char *)*buf, n->version==sanyoV1?"SANYO":
126					(n->version==epsonV1?"EPSON":"OLYMP"));
127		exif_set_short (*buf + 6, n->order, (ExifShort) 1);
128		datao = n->offset;
129		break;
130
131	case olympusV2:
132		*buf_size += 8-6 + 4;
133		*buf = exif_mem_alloc (ne->mem, *buf_size);
134		if (!*buf) {
135			EXIF_LOG_NO_MEMORY(ne->log, "ExifMnoteDataOlympus", *buf_size);
136			return;
137		}
138
139		/* Write the header and the number of entries. */
140		strcpy ((char *)*buf, "OLYMPUS");
141		exif_set_short (*buf + 8, n->order, (ExifShort) (
142			(n->order == EXIF_BYTE_ORDER_INTEL) ?
143			('I' << 8) | 'I' :
144			('M' << 8) | 'M'));
145		exif_set_short (*buf + 10, n->order, (ExifShort) 3);
146		o2 += 4;
147		break;
148
149	case nikonV1:
150		base = MNOTE_NIKON1_TAG_BASE;
151
152		/* v1 has offsets based to main IFD, not makernote IFD */
153		datao += n->offset + 10;
154		/* subtract the size here, so the increment in the next case will not harm us */
155		*buf_size -= 8 + 2;
156	/* Fall through to nikonV2 handler */
157	case nikonV2:
158	/* Write out V0 files in V2 format */
159	case nikonV0:
160		*buf_size += 8 + 2;
161		*buf_size += 4; /* Next IFD pointer */
162		*buf = exif_mem_alloc (ne->mem, *buf_size);
163		if (!*buf) {
164			EXIF_LOG_NO_MEMORY(ne->log, "ExifMnoteDataOlympus", *buf_size);
165			return;
166		}
167
168		/* Write the header and the number of entries. */
169		strcpy ((char *)*buf, "Nikon");
170		(*buf)[6] = n->version;
171
172		if (n->version != nikonV1) {
173			exif_set_short (*buf + 10, n->order, (ExifShort) (
174				(n->order == EXIF_BYTE_ORDER_INTEL) ?
175				('I' << 8) | 'I' :
176				('M' << 8) | 'M'));
177			exif_set_short (*buf + 12, n->order, (ExifShort) 0x2A);
178			exif_set_long (*buf + 14, n->order, (ExifShort) 8);
179			o2 += 2 + 8;
180		}
181		datao -= 10;
182		/* Reset next IFD pointer */
183		exif_set_long (*buf + o2 + 2 + n->count * 12, n->order, 0);
184		break;
185
186	default:
187		return;
188	}
189
190	exif_set_short (*buf + o2, n->order, (ExifShort) n->count);
191	o2 += 2;
192
193	/* Save each entry */
194	for (i = 0; i < n->count; i++) {
195		o = o2 + i * 12;
196		exif_set_short (*buf + o + 0, n->order,
197				(ExifShort) (n->entries[i].tag - base));
198		exif_set_short (*buf + o + 2, n->order,
199				(ExifShort) n->entries[i].format);
200		exif_set_long  (*buf + o + 4, n->order,
201				n->entries[i].components);
202		o += 8;
203		s = exif_format_get_size (n->entries[i].format) *
204						n->entries[i].components;
205		if (s > 65536) {
206			/* Corrupt data: EXIF data size is limited to the
207			 * maximum size of a JPEG segment (64 kb).
208			 */
209			continue;
210		}
211		if (s > 4) {
212			doff = *buf_size;
213			ts = *buf_size + s;
214			t = exif_mem_realloc (ne->mem, *buf,
215						 sizeof (char) * ts);
216			if (!t) {
217				EXIF_LOG_NO_MEMORY(ne->log, "ExifMnoteDataOlympus", ts);
218				return;
219			}
220			*buf = t;
221			*buf_size = ts;
222			exif_set_long (*buf + o, n->order, datao + doff);
223		} else
224			doff = o;
225
226		/* Write the data. */
227		if (n->entries[i].data) {
228			memcpy (*buf + doff, n->entries[i].data, s);
229		} else {
230			/* Most certainly damaged input file */
231			memset (*buf + doff, 0, s);
232		}
233	}
234}
235
236static void
237exif_mnote_data_olympus_load (ExifMnoteData *en,
238			      const unsigned char *buf, unsigned int buf_size)
239{
240	ExifMnoteDataOlympus *n = (ExifMnoteDataOlympus *) en;
241	ExifShort c;
242	size_t i, tcount, o, o2, datao = 6, base = 0;
243
244	if (!n || !buf || !buf_size) {
245		exif_log (en->log, EXIF_LOG_CODE_CORRUPT_DATA,
246			  "ExifMnoteDataOlympus", "Short MakerNote");
247		return;
248	}
249	o2 = 6 + n->offset; /* Start of interesting data */
250	if ((o2 + 10 < o2) || (o2 + 10 < 10) || (o2 + 10 > buf_size)) {
251		exif_log (en->log, EXIF_LOG_CODE_CORRUPT_DATA,
252			  "ExifMnoteDataOlympus", "Short MakerNote");
253		return;
254	}
255
256	/*
257	 * Olympus headers start with "OLYMP" and need to have at least
258	 * a size of 22 bytes (6 for 'OLYMP', 2 other bytes, 2 for the
259	 * number of entries, and 12 for one entry.
260	 *
261	 * Sanyo format is identical and uses identical tags except that
262	 * header starts with "SANYO".
263	 *
264	 * Epson format is identical and uses identical tags except that
265	 * header starts with "EPSON".
266	 *
267	 * Nikon headers start with "Nikon" (6 bytes including '\0'),
268	 * version number (1 or 2).
269	 *
270	 * Version 1 continues with 0, 1, 0, number_of_tags,
271	 * or just with number_of_tags (models D1H, D1X...).
272	 *
273	 * Version 2 continues with an unknown byte (0 or 10),
274	 * two unknown bytes (0), "MM" or "II", another byte 0 and
275	 * lastly 0x2A.
276	 */
277	n->version = exif_mnote_data_olympus_identify_variant(buf+o2, buf_size-o2);
278	switch (n->version) {
279	case olympusV1:
280	case sanyoV1:
281	case epsonV1:
282		exif_log (en->log, EXIF_LOG_CODE_DEBUG, "ExifMnoteDataOlympus",
283			"Parsing Olympus/Sanyo/Epson maker note v1...");
284
285		/* The number of entries is at position 8. */
286		if (buf[o2 + 6] == 1)
287			n->order = EXIF_BYTE_ORDER_INTEL;
288		else if (buf[o2 + 6 + 1] == 1)
289			n->order = EXIF_BYTE_ORDER_MOTOROLA;
290		o2 += 8;
291		if (o2 + 2 > buf_size) return;
292		c = exif_get_short (buf + o2, n->order);
293		if ((!(c & 0xFF)) && (c > 0x500)) {
294			if (n->order == EXIF_BYTE_ORDER_INTEL) {
295				n->order = EXIF_BYTE_ORDER_MOTOROLA;
296			} else {
297				n->order = EXIF_BYTE_ORDER_INTEL;
298			}
299		}
300		break;
301
302	case olympusV2:
303		/* Olympus S760, S770 */
304		datao = o2;
305		o2 += 8;
306		exif_log (en->log, EXIF_LOG_CODE_DEBUG, "ExifMnoteDataOlympus",
307			"Parsing Olympus maker note v2 (0x%02x, %02x, %02x, %02x)...",
308			buf[o2], buf[o2 + 1], buf[o2 + 2], buf[o2 + 3]);
309
310		if ((buf[o2] == 'I') && (buf[o2 + 1] == 'I'))
311			n->order = EXIF_BYTE_ORDER_INTEL;
312		else if ((buf[o2] == 'M') && (buf[o2 + 1] == 'M'))
313			n->order = EXIF_BYTE_ORDER_MOTOROLA;
314
315		/* The number of entries is at position 8+4. */
316		o2 += 4;
317		break;
318
319	case nikonV1:
320		o2 += 6;
321		if (o2 >= buf_size) return;
322		exif_log (en->log, EXIF_LOG_CODE_DEBUG, "ExifMnoteDataOlympus",
323			"Parsing Nikon maker note v1 (0x%02x, %02x, %02x, "
324			"%02x, %02x, %02x, %02x, %02x)...",
325			buf[o2 + 0], buf[o2 + 1], buf[o2 + 2], buf[o2 + 3],
326			buf[o2 + 4], buf[o2 + 5], buf[o2 + 6], buf[o2 + 7]);
327
328		/* Skip version number */
329		o2 += 1;
330
331		/* Skip an unknown byte (00 or 0A). */
332		o2 += 1;
333
334		base = MNOTE_NIKON1_TAG_BASE;
335		/* Fix endianness, if needed */
336		if (o2 + 2 > buf_size) return;
337		c = exif_get_short (buf + o2, n->order);
338		if ((!(c & 0xFF)) && (c > 0x500)) {
339			if (n->order == EXIF_BYTE_ORDER_INTEL) {
340				n->order = EXIF_BYTE_ORDER_MOTOROLA;
341			} else {
342				n->order = EXIF_BYTE_ORDER_INTEL;
343			}
344		}
345		break;
346
347	case nikonV2:
348		o2 += 6;
349		if (o2 >= buf_size) return;
350		exif_log (en->log, EXIF_LOG_CODE_DEBUG, "ExifMnoteDataOlympus",
351			"Parsing Nikon maker note v2 (0x%02x, %02x, %02x, "
352			"%02x, %02x, %02x, %02x, %02x)...",
353			buf[o2 + 0], buf[o2 + 1], buf[o2 + 2], buf[o2 + 3],
354			buf[o2 + 4], buf[o2 + 5], buf[o2 + 6], buf[o2 + 7]);
355
356		/* Skip version number */
357		o2 += 1;
358
359		/* Skip an unknown byte (00 or 0A). */
360		o2 += 1;
361
362		/* Skip 2 unknown bytes (00 00). */
363		o2 += 2;
364
365		/*
366		 * Byte order. From here the data offset
367		 * gets calculated.
368		 */
369		datao = o2;
370		if (o2 >= buf_size) return;
371		if (!strncmp ((char *)&buf[o2], "II", 2))
372			n->order = EXIF_BYTE_ORDER_INTEL;
373		else if (!strncmp ((char *)&buf[o2], "MM", 2))
374			n->order = EXIF_BYTE_ORDER_MOTOROLA;
375		else {
376			exif_log (en->log, EXIF_LOG_CODE_DEBUG,
377				"ExifMnoteDataOlympus", "Unknown "
378				"byte order '%c%c'", buf[o2],
379				buf[o2 + 1]);
380			return;
381		}
382		o2 += 2;
383
384		/* Skip 2 unknown bytes (00 2A). */
385		o2 += 2;
386
387		/* Go to where the number of entries is. */
388		if (o2 + 4 > buf_size) return;
389		o2 = datao + exif_get_long (buf + o2, n->order);
390		break;
391
392	case nikonV0:
393		exif_log (en->log, EXIF_LOG_CODE_DEBUG, "ExifMnoteDataOlympus",
394			"Parsing Nikon maker note v0 (0x%02x, %02x, %02x, "
395			"%02x, %02x, %02x, %02x, %02x)...",
396			buf[o2 + 0], buf[o2 + 1], buf[o2 + 2], buf[o2 + 3],
397			buf[o2 + 4], buf[o2 + 5], buf[o2 + 6], buf[o2 + 7]);
398		/* 00 1b is # of entries in Motorola order - the rest should also be in MM order */
399		n->order = EXIF_BYTE_ORDER_MOTOROLA;
400		break;
401
402	default:
403		exif_log (en->log, EXIF_LOG_CODE_DEBUG, "ExifMnoteDataOlympus",
404			"Unknown Olympus variant %i.", n->version);
405		return;
406	}
407
408	/* Sanity check the offset */
409	if ((o2 + 2 < o2) || (o2 + 2 < 2) || (o2 + 2 > buf_size)) {
410		exif_log (en->log, EXIF_LOG_CODE_CORRUPT_DATA,
411			  "ExifMnoteOlympus", "Short MakerNote");
412		return;
413	}
414
415	/* Read the number of tags */
416	c = exif_get_short (buf + o2, n->order);
417	o2 += 2;
418
419	/* Remove any old entries */
420	exif_mnote_data_olympus_clear (n);
421
422	/* Reserve enough space for all the possible MakerNote tags */
423	n->entries = exif_mem_alloc (en->mem, sizeof (MnoteOlympusEntry) * c);
424	if (!n->entries) {
425		EXIF_LOG_NO_MEMORY(en->log, "ExifMnoteOlympus", sizeof (MnoteOlympusEntry) * c);
426		return;
427	}
428
429	/* Parse all c entries, storing ones that are successfully parsed */
430	tcount = 0;
431	for (i = c, o = o2; i; --i, o += 12) {
432		size_t s;
433		if ((o + 12 < o) || (o + 12 < 12) || (o + 12 > buf_size)) {
434			exif_log (en->log, EXIF_LOG_CODE_CORRUPT_DATA,
435				  "ExifMnoteOlympus", "Short MakerNote");
436			break;
437		}
438
439	    n->entries[tcount].tag        = exif_get_short (buf + o, n->order) + base;
440	    n->entries[tcount].format     = exif_get_short (buf + o + 2, n->order);
441	    n->entries[tcount].components = exif_get_long (buf + o + 4, n->order);
442	    n->entries[tcount].order      = n->order;
443
444	    exif_log (en->log, EXIF_LOG_CODE_DEBUG, "ExifMnoteOlympus",
445		      "Loading entry 0x%x ('%s')...", n->entries[tcount].tag,
446		      mnote_olympus_tag_get_name (n->entries[tcount].tag));
447/*	    exif_log (en->log, EXIF_LOG_CODE_DEBUG, "ExifMnoteOlympus",
448			    "0x%x %d %ld*(%d)",
449		    n->entries[tcount].tag,
450		    n->entries[tcount].format,
451		    n->entries[tcount].components,
452		    (int)exif_format_get_size(n->entries[tcount].format)); */
453
454	    /*
455	     * Size? If bigger than 4 bytes, the actual data is not
456	     * in the entry but somewhere else (offset).
457	     */
458	    s = exif_format_get_size (n->entries[tcount].format) *
459		   			 n->entries[tcount].components;
460		n->entries[tcount].size = s;
461		if (s) {
462			size_t dataofs = o + 8;
463			if (s > 4) {
464				/* The data in this case is merely a pointer */
465				dataofs = exif_get_long (buf + dataofs, n->order) + datao;
466#ifdef EXIF_OVERCOME_SANYO_OFFSET_BUG
467				/* Some Sanyo models (e.g. VPC-C5, C40) suffer from a bug when
468				 * writing the offset for the MNOTE_OLYMPUS_TAG_THUMBNAILIMAGE
469				 * tag in its MakerNote. The offset is actually the absolute
470				 * position in the file instead of the position within the IFD.
471				 */
472			    if (dataofs + s > buf_size && n->version == sanyoV1) {
473					/* fix pointer */
474					dataofs -= datao + 6;
475					exif_log (en->log, EXIF_LOG_CODE_DEBUG,
476						  "ExifMnoteOlympus",
477						  "Inconsistent thumbnail tag offset; attempting to recover");
478			    }
479#endif
480			}
481			if ((dataofs + s < dataofs) || (dataofs + s < s) ||
482			    (dataofs + s > buf_size)) {
483				exif_log (en->log, EXIF_LOG_CODE_DEBUG,
484					  "ExifMnoteOlympus",
485					  "Tag data past end of buffer (%zu > %u)",
486					  dataofs + s, buf_size);
487				continue;
488			}
489
490			n->entries[tcount].data = exif_mem_alloc (en->mem, s);
491			if (!n->entries[tcount].data) {
492				EXIF_LOG_NO_MEMORY(en->log, "ExifMnoteOlympus", s);
493				continue;
494			}
495			memcpy (n->entries[tcount].data, buf + dataofs, s);
496		}
497
498		/* Tag was successfully parsed */
499		++tcount;
500	}
501	/* Store the count of successfully parsed tags */
502	n->count = tcount;
503}
504
505static unsigned int
506exif_mnote_data_olympus_count (ExifMnoteData *n)
507{
508	return n ? ((ExifMnoteDataOlympus *) n)->count : 0;
509}
510
511static unsigned int
512exif_mnote_data_olympus_get_id (ExifMnoteData *d, unsigned int n)
513{
514	ExifMnoteDataOlympus *note = (ExifMnoteDataOlympus *) d;
515
516	if (!note) return 0;
517	if (note->count <= n) return 0;
518	return note->entries[n].tag;
519}
520
521static const char *
522exif_mnote_data_olympus_get_name (ExifMnoteData *d, unsigned int i)
523{
524	ExifMnoteDataOlympus *n = (ExifMnoteDataOlympus *) d;
525
526	if (!n) return NULL;
527	if (i >= n->count) return NULL;
528	return mnote_olympus_tag_get_name (n->entries[i].tag);
529}
530
531static const char *
532exif_mnote_data_olympus_get_title (ExifMnoteData *d, unsigned int i)
533{
534	ExifMnoteDataOlympus *n = (ExifMnoteDataOlympus *) d;
535
536	if (!n) return NULL;
537	if (i >= n->count) return NULL;
538        return mnote_olympus_tag_get_title (n->entries[i].tag);
539}
540
541static const char *
542exif_mnote_data_olympus_get_description (ExifMnoteData *d, unsigned int i)
543{
544	ExifMnoteDataOlympus *n = (ExifMnoteDataOlympus *) d;
545
546	if (!n) return NULL;
547	if (i >= n->count) return NULL;
548        return mnote_olympus_tag_get_description (n->entries[i].tag);
549}
550
551static void
552exif_mnote_data_olympus_set_byte_order (ExifMnoteData *d, ExifByteOrder o)
553{
554	ExifByteOrder o_orig;
555	ExifMnoteDataOlympus *n = (ExifMnoteDataOlympus *) d;
556	unsigned int i;
557
558	if (!n) return;
559
560	o_orig = n->order;
561	n->order = o;
562	for (i = 0; i < n->count; i++) {
563		n->entries[i].order = o;
564		exif_array_set_byte_order (n->entries[i].format, n->entries[i].data,
565				n->entries[i].components, o_orig, o);
566	}
567}
568
569static void
570exif_mnote_data_olympus_set_offset (ExifMnoteData *n, unsigned int o)
571{
572	if (n) ((ExifMnoteDataOlympus *) n)->offset = o;
573}
574
575static enum OlympusVersion
576exif_mnote_data_olympus_identify_variant (const unsigned char *buf,
577		unsigned int buf_size)
578{
579	/* Olympus, Nikon, Sanyo, Epson */
580	if (buf_size >= 8) {
581		/* Match the terminating NUL character, too */
582		if (!memcmp (buf, "OLYMPUS", 8))
583			   return olympusV2;
584		else if (!memcmp (buf, "OLYMP", 6))
585			   return olympusV1;
586		else if (!memcmp (buf, "SANYO", 6))
587			   return sanyoV1;
588		else if (!memcmp (buf, "EPSON", 6))
589			   return epsonV1;
590		else if (!memcmp (buf, "Nikon", 6)) {
591			switch (buf[6]) {
592				case 1:  return nikonV1;
593				case 2:  return nikonV2;
594				default: return 0; /* Unrecognized Nikon variant */
595			}
596		}
597	}
598
599	/* Another variant of Nikon */
600	if ((buf_size >= 2) && (buf[0] == 0x00) && (buf[1] == 0x1b)) {
601		return nikonV0;
602	}
603
604	return unrecognized;
605}
606
607int
608exif_mnote_data_olympus_identify (const ExifData *ed, const ExifEntry *e)
609{
610	int variant = exif_mnote_data_olympus_identify_variant(e->data, e->size);
611
612	if (variant == nikonV0) {
613		/* This variant needs some extra checking with the Make */
614		char value[5];
615		ExifEntry *em = exif_data_get_entry (ed, EXIF_TAG_MAKE);
616		variant = unrecognized;
617
618		if (em) {
619			const char *v = exif_entry_get_value (em, value, sizeof(value));
620			if (v && (!strncmp (v, "Nikon", sizeof(value)) ||
621					  !strncmp (v, "NIKON", sizeof(value)) ))
622				/* When saved, this variant will be written out like the
623				 * alternative nikonV2 form above instead
624				 */
625				variant = nikonV0;
626		}
627	}
628
629	return variant;
630}
631
632
633ExifMnoteData *
634exif_mnote_data_olympus_new (ExifMem *mem)
635{
636	ExifMnoteData *d;
637
638	if (!mem) return NULL;
639
640	d = exif_mem_alloc (mem, sizeof (ExifMnoteDataOlympus));
641	if (!d) return NULL;
642
643	exif_mnote_data_construct (d, mem);
644
645	/* Set up function pointers */
646	d->methods.free            = exif_mnote_data_olympus_free;
647	d->methods.set_byte_order  = exif_mnote_data_olympus_set_byte_order;
648	d->methods.set_offset      = exif_mnote_data_olympus_set_offset;
649	d->methods.load            = exif_mnote_data_olympus_load;
650	d->methods.save            = exif_mnote_data_olympus_save;
651	d->methods.count           = exif_mnote_data_olympus_count;
652	d->methods.get_id          = exif_mnote_data_olympus_get_id;
653	d->methods.get_name        = exif_mnote_data_olympus_get_name;
654	d->methods.get_title       = exif_mnote_data_olympus_get_title;
655	d->methods.get_description = exif_mnote_data_olympus_get_description;
656	d->methods.get_value       = exif_mnote_data_olympus_get_value;
657
658	return d;
659}
660