/*! If MakerNote is recognized, load it.
 *
 * \param[in,out] data #ExifData
 * \param[in] d pointer to raw EXIF data
 * \param[in] ds length of data at d
 */
static void
interpret_maker_note(ExifData *data, const unsigned char *d, unsigned int ds)
{
	int mnoteid;
	ExifEntry* e = exif_data_get_entry (data, EXIF_TAG_MAKER_NOTE);
	if (!e)
		return;
	
	if ((mnoteid = exif_mnote_data_olympus_identify (data, e)) != 0) {
		exif_log (data->priv->log, EXIF_LOG_CODE_DEBUG,
			"ExifData", "Olympus MakerNote variant type %d", mnoteid);
		data->priv->md = exif_mnote_data_olympus_new (data->priv->mem);

	} else if ((mnoteid = exif_mnote_data_canon_identify (data, e)) != 0) {
		exif_log (data->priv->log, EXIF_LOG_CODE_DEBUG,
			"ExifData", "Canon MakerNote variant type %d", mnoteid);
		data->priv->md = exif_mnote_data_canon_new (data->priv->mem, data->priv->options);

	} else if ((mnoteid = exif_mnote_data_fuji_identify (data, e)) != 0) {
		exif_log (data->priv->log, EXIF_LOG_CODE_DEBUG,
			"ExifData", "Fuji MakerNote variant type %d", mnoteid);
		data->priv->md = exif_mnote_data_fuji_new (data->priv->mem);

	/* NOTE: Must do Pentax detection last because some of the
	 * heuristics are pretty general. */
	} else if ((mnoteid = exif_mnote_data_pentax_identify (data, e)) != 0) {
		exif_log (data->priv->log, EXIF_LOG_CODE_DEBUG,
			"ExifData", "Pentax MakerNote variant type %d", mnoteid);
		data->priv->md = exif_mnote_data_pentax_new (data->priv->mem);
	}

	/* 
	 * If we are able to interpret the maker note, do so.
	 */
	if (data->priv->md) {
		exif_mnote_data_log (data->priv->md, data->priv->log);
		exif_mnote_data_set_byte_order (data->priv->md,
						data->priv->order);
		exif_mnote_data_set_offset (data->priv->md,
					    data->priv->offset_mnote);
		exif_mnote_data_load (data->priv->md, d, ds);
	}
}
예제 #2
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void
exif_data_load_data (ExifData *data, const unsigned char *d_orig,
		     unsigned int ds_orig)
{
	unsigned int l;
	ExifLong offset;
	ExifShort n;
	const unsigned char *d = d_orig;
	unsigned int ds = ds_orig, len;

	if (!data || !data->priv || !d || !ds) 
		return;

	exif_log (data->priv->log, EXIF_LOG_CODE_DEBUG, "ExifData",
		  "Parsing %i byte(s) EXIF data...\n", ds);

	/*
	 * It can be that the data starts with the EXIF header. If it does
	 * not, search the EXIF marker.
	 */
	if (ds < 6) {
		LOG_TOO_SMALL;
		return;
	}
	if (!memcmp (d, ExifHeader, 6)) {
		exif_log (data->priv->log, EXIF_LOG_CODE_DEBUG, "ExifData",
			  "Found EXIF header.");
	} else {
		while (1) {
			while ((d[0] == 0xff) && ds) {
				d++;
				ds--;
			}

			/* JPEG_MARKER_SOI */
			if (d[0] == JPEG_MARKER_SOI) {
				d++;
				ds--;
				continue;
			}

			/* JPEG_MARKER_APP0 */
			if (d[0] == JPEG_MARKER_APP0) {
				d++;
				ds--;
				l = (d[0] << 8) | d[1];
				if (l > ds)
					return;
				d += l;
				ds -= l;
				continue;
			}

			/* JPEG_MARKER_APP1 */
			if (d[0] == JPEG_MARKER_APP1)
				break;

			/* Unknown marker or data. Give up. */
			exif_log (data->priv->log, EXIF_LOG_CODE_CORRUPT_DATA,
				  "ExifData", _("EXIF marker not found."));
			return;
		}
		d++;
		ds--;
		if (ds < 2) {
			LOG_TOO_SMALL;
			return;
		}
		len = (d[0] << 8) | d[1];
		exif_log (data->priv->log, EXIF_LOG_CODE_DEBUG, "ExifData",
			  "We have to deal with %i byte(s) of EXIF data.",
			  len);
		d += 2;
		ds -= 2;
	}

	/*
	 * Verify the exif header
	 * (offset 2, length 6).
	 */
	if (ds < 6) {
		LOG_TOO_SMALL;
		return;
	}
	if (memcmp (d, ExifHeader, 6)) {
		exif_log (data->priv->log, EXIF_LOG_CODE_CORRUPT_DATA,
			  "ExifData", _("EXIF header not found."));
		return;
	}

	exif_log (data->priv->log, EXIF_LOG_CODE_DEBUG, "ExifData",
		  "Found EXIF header.");

	/* Byte order (offset 6, length 2) */
	if (ds < 14)
		return;
	if (!memcmp (d + 6, "II", 2))
		data->priv->order = EXIF_BYTE_ORDER_INTEL;
	else if (!memcmp (d + 6, "MM", 2))
		data->priv->order = EXIF_BYTE_ORDER_MOTOROLA;
	else {
		exif_log (data->priv->log, EXIF_LOG_CODE_CORRUPT_DATA,
			  "ExifData", _("Unknown encoding."));
		return;
	}

	/* Fixed value */
	if (exif_get_short (d + 8, data->priv->order) != 0x002a)
		return;

	/* IFD 0 offset */
	offset = exif_get_long (d + 10, data->priv->order);
	exif_log (data->priv->log, EXIF_LOG_CODE_DEBUG, "ExifData", 
		  "IFD 0 at %i.", (int) offset);

	/* Parse the actual exif data (usually offset 14 from start) */
	exif_data_load_data_content (data, EXIF_IFD_0, d + 6, ds - 6, offset, 0);

	/* IFD 1 offset */
	if (offset + 6 + 2 > ds) {
		return;
	}
	n = exif_get_short (d + 6 + offset, data->priv->order);
	if (offset + 6 + 2 + 12 * n + 4 > ds) {
		return;
	}
	offset = exif_get_long (d + 6 + offset + 2 + 12 * n, data->priv->order);
	if (offset) {
		exif_log (data->priv->log, EXIF_LOG_CODE_DEBUG, "ExifData",
			  "IFD 1 at %i.", (int) offset);

		/* Sanity check. */
		if (offset > ds - 6) {
			exif_log (data->priv->log, EXIF_LOG_CODE_CORRUPT_DATA,
				  "ExifData", "Bogus offset of IFD1.");
		} else {
		   exif_data_load_data_content (data, EXIF_IFD_1, d + 6, ds - 6, offset, 0);
		}
	}

	/*
	 * If we got an EXIF_TAG_MAKER_NOTE, try to interpret it. Some
	 * cameras use pointers in the maker note tag that point to the
	 * space between IFDs. Here is the only place where we have access
	 * to that data.
	 */
	switch (exif_data_get_type_maker_note (data)) {
	case EXIF_DATA_TYPE_MAKER_NOTE_OLYMPUS:
	case EXIF_DATA_TYPE_MAKER_NOTE_NIKON:
		data->priv->md = exif_mnote_data_olympus_new (data->priv->mem);
		break;
	case EXIF_DATA_TYPE_MAKER_NOTE_PENTAX:
	case EXIF_DATA_TYPE_MAKER_NOTE_CASIO:
		data->priv->md = exif_mnote_data_pentax_new (data->priv->mem);
		break;
	case EXIF_DATA_TYPE_MAKER_NOTE_CANON:
		data->priv->md = exif_mnote_data_canon_new (data->priv->mem, data->priv->options);
		break;
	case EXIF_DATA_TYPE_MAKER_NOTE_FUJI:
		data->priv->md = exif_mnote_data_fuji_new (data->priv->mem);
		break;
	default:
		break;
	}

	/* 
	 * If we are able to interpret the maker note, do so.
	 */
	if (data->priv->md) {
		exif_mnote_data_log (data->priv->md, data->priv->log);
		exif_mnote_data_set_byte_order (data->priv->md,
						data->priv->order);
		exif_mnote_data_set_offset (data->priv->md,
					    data->priv->offset_mnote);
		exif_mnote_data_load (data->priv->md, d, ds);
	}

	if (data->priv->options & EXIF_DATA_OPTION_FOLLOW_SPECIFICATION)
		exif_data_fix (data);
}