exif.c

/*
   +----------------------------------------------------------------------+
   | PHP Version 7                                                        |
   +----------------------------------------------------------------------+
   | Copyright (c) 1997-2018 The PHP Group                                |
   +----------------------------------------------------------------------+
   | This source file is subject to version 3.01 of the PHP license,      |
   | that is bundled with this package in the file LICENSE, and is        |
   | available through the world-wide-web at the following url:           |
   | http://www.php.net/license/3_01.txt                                  |
   | If you did not receive a copy of the PHP license and are unable to   |
   | obtain it through the world-wide-web, please send a note to          |
   | license@php.net so we can mail you a copy immediately.               |
   +----------------------------------------------------------------------+
   | Authors: Rasmus Lerdorf <rasmus@php.net>                             |
   |          Marcus Boerger <helly@php.net>                              |
   +----------------------------------------------------------------------+
 */

/* $Id$ */

/*  ToDos
 *
 * 	See if example images from http://www.exif.org have illegal
 * 		thumbnail sizes or if code is corrupt.
 * 	Create/Update exif headers.
 * 	Create/Remove/Update image thumbnails.
 */

/*  Security
 *
 *  At current time i do not see any security problems but a potential
 *  attacker could generate an image with recursive ifd pointers...(Marcus)
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include "php.h"
#include "ext/standard/file.h"

#if HAVE_EXIF

/* When EXIF_DEBUG is defined the module generates a lot of debug messages
 * that help understanding what is going on. This can and should be used
 * while extending the module as it shows if you are at the right position.
 * You are always considered to have a copy of TIFF6.0 and EXIF2.10 standard.
 */
#undef EXIF_DEBUG

#ifdef EXIF_DEBUG
#define EXIFERR_DC , const char *_file, size_t _line
#define EXIFERR_CC , __FILE__, __LINE__
#else
#define EXIFERR_DC
#define EXIFERR_CC
#endif

#undef EXIF_JPEG2000

#include "php_exif.h"
#include <math.h>
#include "php_ini.h"
#include "ext/standard/php_string.h"
#include "ext/standard/php_image.h"
#include "ext/standard/info.h"

/* needed for ssize_t definition */
#include <sys/types.h>

typedef unsigned char uchar;

#ifndef safe_emalloc
# define safe_emalloc(a,b,c) emalloc((a)*(b)+(c))
#endif
#ifndef safe_erealloc
# define safe_erealloc(p,a,b,c) erealloc(p, (a)*(b)+(c))
#endif

#ifndef TRUE
#	define TRUE 1
#	define FALSE 0
#endif

#ifndef max
#	define max(a,b) ((a)>(b) ? (a) : (b))
#endif

#define EFREE_IF(ptr)	if (ptr) efree(ptr)

#define MAX_IFD_NESTING_LEVEL 100

/* {{{ arginfo */
ZEND_BEGIN_ARG_INFO(arginfo_exif_tagname, 0)
	ZEND_ARG_INFO(0, index)
ZEND_END_ARG_INFO()

ZEND_BEGIN_ARG_INFO_EX(arginfo_exif_read_data, 0, 0, 1)
	ZEND_ARG_INFO(0, filename)
	ZEND_ARG_INFO(0, sections_needed)
	ZEND_ARG_INFO(0, sub_arrays)
	ZEND_ARG_INFO(0, read_thumbnail)
ZEND_END_ARG_INFO()

ZEND_BEGIN_ARG_INFO_EX(arginfo_exif_thumbnail, 0, 0, 1)
	ZEND_ARG_INFO(0, filename)
	ZEND_ARG_INFO(1, width)
	ZEND_ARG_INFO(1, height)
	ZEND_ARG_INFO(1, imagetype)
ZEND_END_ARG_INFO()

ZEND_BEGIN_ARG_INFO(arginfo_exif_imagetype, 0)
	ZEND_ARG_INFO(0, imagefile)
ZEND_END_ARG_INFO()

/* }}} */

/* {{{ exif_functions[]
 */
const zend_function_entry exif_functions[] = {
	PHP_FE(exif_read_data, arginfo_exif_read_data)
	PHP_FALIAS(read_exif_data, exif_read_data, arginfo_exif_read_data)
	PHP_FE(exif_tagname, arginfo_exif_tagname)
	PHP_FE(exif_thumbnail, arginfo_exif_thumbnail)
	PHP_FE(exif_imagetype, arginfo_exif_imagetype)
	PHP_FE_END
};
/* }}} */

/* {{{ PHP_MINFO_FUNCTION
 */
PHP_MINFO_FUNCTION(exif)
{
	php_info_print_table_start();
	php_info_print_table_row(2, "EXIF Support", "enabled");
	php_info_print_table_row(2, "EXIF Version", PHP_EXIF_VERSION);
	php_info_print_table_row(2, "Supported EXIF Version", "0220");
	php_info_print_table_row(2, "Supported filetypes", "JPEG,TIFF");
	php_info_print_table_end();
	DISPLAY_INI_ENTRIES();
}
/* }}} */

ZEND_BEGIN_MODULE_GLOBALS(exif)
	char * encode_unicode;
	char * decode_unicode_be;
	char * decode_unicode_le;
	char * encode_jis;
	char * decode_jis_be;
	char * decode_jis_le;
ZEND_END_MODULE_GLOBALS(exif)

ZEND_DECLARE_MODULE_GLOBALS(exif)
#define EXIF_G(v) ZEND_MODULE_GLOBALS_ACCESSOR(exif, v)

#if defined(ZTS) && defined(COMPILE_DL_EXIF)
ZEND_TSRMLS_CACHE_DEFINE()
#endif

/* {{{ PHP_INI
 */

ZEND_INI_MH(OnUpdateEncode)
{
	if (new_value && ZSTR_LEN(new_value)) {
		const zend_encoding **return_list;
		size_t return_size;
		if (FAILURE == zend_multibyte_parse_encoding_list(ZSTR_VAL(new_value), ZSTR_LEN(new_value),
	&return_list, &return_size, 0)) {
			php_error_docref(NULL, E_WARNING, "Illegal encoding ignored: '%s'", ZSTR_VAL(new_value));
			return FAILURE;
		}
		efree(return_list);
	}
	return OnUpdateString(entry, new_value, mh_arg1, mh_arg2, mh_arg3, stage);
}

ZEND_INI_MH(OnUpdateDecode)
{
	if (new_value) {
		const zend_encoding **return_list;
		size_t return_size;
		if (FAILURE == zend_multibyte_parse_encoding_list(ZSTR_VAL(new_value), ZSTR_LEN(new_value),
	&return_list, &return_size, 0)) {
			php_error_docref(NULL, E_WARNING, "Illegal encoding ignored: '%s'", ZSTR_VAL(new_value));
			return FAILURE;
		}
		efree(return_list);
	}
	return OnUpdateString(entry, new_value, mh_arg1, mh_arg2, mh_arg3, stage);
}

PHP_INI_BEGIN()
    STD_PHP_INI_ENTRY("exif.encode_unicode",          "ISO-8859-15", PHP_INI_ALL, OnUpdateEncode, encode_unicode,    zend_exif_globals, exif_globals)
    STD_PHP_INI_ENTRY("exif.decode_unicode_motorola", "UCS-2BE",     PHP_INI_ALL, OnUpdateDecode, decode_unicode_be, zend_exif_globals, exif_globals)
    STD_PHP_INI_ENTRY("exif.decode_unicode_intel",    "UCS-2LE",     PHP_INI_ALL, OnUpdateDecode, decode_unicode_le, zend_exif_globals, exif_globals)
    STD_PHP_INI_ENTRY("exif.encode_jis",              "",            PHP_INI_ALL, OnUpdateEncode, encode_jis,        zend_exif_globals, exif_globals)
    STD_PHP_INI_ENTRY("exif.decode_jis_motorola",     "JIS",         PHP_INI_ALL, OnUpdateDecode, decode_jis_be,     zend_exif_globals, exif_globals)
    STD_PHP_INI_ENTRY("exif.decode_jis_intel",        "JIS",         PHP_INI_ALL, OnUpdateDecode, decode_jis_le,     zend_exif_globals, exif_globals)
PHP_INI_END()
/* }}} */

/* {{{ PHP_GINIT_FUNCTION
 */
static PHP_GINIT_FUNCTION(exif)
{
#if defined(COMPILE_DL_EXIF) && defined(ZTS)
	ZEND_TSRMLS_CACHE_UPDATE();
#endif
	exif_globals->encode_unicode    = NULL;
	exif_globals->decode_unicode_be = NULL;
	exif_globals->decode_unicode_le = NULL;
	exif_globals->encode_jis        = NULL;
	exif_globals->decode_jis_be     = NULL;
	exif_globals->decode_jis_le     = NULL;
}
/* }}} */

/* {{{ PHP_MINIT_FUNCTION(exif)
   Get the size of an image as 4-element array */
PHP_MINIT_FUNCTION(exif)
{
	REGISTER_INI_ENTRIES();
	if (zend_hash_str_exists(&module_registry, "mbstring", sizeof("mbstring")-1)) {
		REGISTER_LONG_CONSTANT("EXIF_USE_MBSTRING", 1, CONST_CS | CONST_PERSISTENT);
	} else {
		REGISTER_LONG_CONSTANT("EXIF_USE_MBSTRING", 0, CONST_CS | CONST_PERSISTENT);
	}
	return SUCCESS;
}
/* }}} */

/* {{{ PHP_MSHUTDOWN_FUNCTION
 */
PHP_MSHUTDOWN_FUNCTION(exif)
{
	UNREGISTER_INI_ENTRIES();
	return SUCCESS;
}
/* }}} */

/* {{{ exif dependencies */
static const zend_module_dep exif_module_deps[] = {
	ZEND_MOD_REQUIRED("standard")
	ZEND_MOD_OPTIONAL("mbstring")
	ZEND_MOD_END
};
/* }}} */

/* {{{ exif_module_entry
 */
zend_module_entry exif_module_entry = {
	STANDARD_MODULE_HEADER_EX, NULL,
	exif_module_deps,
	"exif",
	exif_functions,
	PHP_MINIT(exif),
	PHP_MSHUTDOWN(exif),
	NULL, NULL,
	PHP_MINFO(exif),
	PHP_EXIF_VERSION,
	PHP_MODULE_GLOBALS(exif),
	PHP_GINIT(exif),
	NULL,
	NULL,
	STANDARD_MODULE_PROPERTIES_EX
};
/* }}} */

#ifdef COMPILE_DL_EXIF
ZEND_GET_MODULE(exif)
#endif

/* {{{ php_strnlen
 * get length of string if buffer if less than buffer size or buffer size */
static size_t php_strnlen(char* str, size_t maxlen) {
	size_t len = 0;

	if (str && maxlen && *str) {
		do {
			len++;
		} while (--maxlen && *(++str));
	}
	return len;
}
/* }}} */

/* {{{ error messages
*/
static const char * EXIF_ERROR_FILEEOF   = "Unexpected end of file reached";
static const char * EXIF_ERROR_CORRUPT   = "File structure corrupted";
static const char * EXIF_ERROR_THUMBEOF  = "Thumbnail goes IFD boundary or end of file reached";
static const char * EXIF_ERROR_FSREALLOC = "Illegal reallocating of undefined file section";

#define EXIF_ERRLOG_FILEEOF(ImageInfo)    exif_error_docref(NULL EXIFERR_CC, ImageInfo, E_WARNING, "%s", EXIF_ERROR_FILEEOF);
#define EXIF_ERRLOG_CORRUPT(ImageInfo)    exif_error_docref(NULL EXIFERR_CC, ImageInfo, E_WARNING, "%s", EXIF_ERROR_CORRUPT);
#define EXIF_ERRLOG_THUMBEOF(ImageInfo)   exif_error_docref(NULL EXIFERR_CC, ImageInfo, E_WARNING, "%s", EXIF_ERROR_THUMBEOF);
#define EXIF_ERRLOG_FSREALLOC(ImageInfo)  exif_error_docref(NULL EXIFERR_CC, ImageInfo, E_WARNING, "%s", EXIF_ERROR_FSREALLOC);
/* }}} */

/* {{{ format description defines
   Describes format descriptor
*/
static int php_tiff_bytes_per_format[] = {0, 1, 1, 2, 4, 8, 1, 1, 2, 4, 8, 4, 8, 1};
#define NUM_FORMATS 13

#define TAG_FMT_BYTE       1
#define TAG_FMT_STRING     2
#define TAG_FMT_USHORT     3
#define TAG_FMT_ULONG      4
#define TAG_FMT_URATIONAL  5
#define TAG_FMT_SBYTE      6
#define TAG_FMT_UNDEFINED  7
#define TAG_FMT_SSHORT     8
#define TAG_FMT_SLONG      9
#define TAG_FMT_SRATIONAL 10
#define TAG_FMT_SINGLE    11
#define TAG_FMT_DOUBLE    12
#define TAG_FMT_IFD       13

#ifdef EXIF_DEBUG
static char *exif_get_tagformat(int format)
{
	switch(format) {
		case TAG_FMT_BYTE:      return "BYTE";
		case TAG_FMT_STRING:    return "STRING";
		case TAG_FMT_USHORT:    return "USHORT";
		case TAG_FMT_ULONG:     return "ULONG";
		case TAG_FMT_URATIONAL: return "URATIONAL";
		case TAG_FMT_SBYTE:     return "SBYTE";
		case TAG_FMT_UNDEFINED: return "UNDEFINED";
		case TAG_FMT_SSHORT:    return "SSHORT";
		case TAG_FMT_SLONG:     return "SLONG";
		case TAG_FMT_SRATIONAL: return "SRATIONAL";
		case TAG_FMT_SINGLE:    return "SINGLE";
		case TAG_FMT_DOUBLE:    return "DOUBLE";
		case TAG_FMT_IFD:       return "IFD";
	}
	return "*Illegal";
}
#endif

/* Describes tag values */
#define TAG_GPS_VERSION_ID              0x0000
#define TAG_GPS_LATITUDE_REF            0x0001
#define TAG_GPS_LATITUDE                0x0002
#define TAG_GPS_LONGITUDE_REF           0x0003
#define TAG_GPS_LONGITUDE               0x0004
#define TAG_GPS_ALTITUDE_REF            0x0005
#define TAG_GPS_ALTITUDE                0x0006
#define TAG_GPS_TIME_STAMP              0x0007
#define TAG_GPS_SATELLITES              0x0008
#define TAG_GPS_STATUS                  0x0009
#define TAG_GPS_MEASURE_MODE            0x000A
#define TAG_GPS_DOP                     0x000B
#define TAG_GPS_SPEED_REF               0x000C
#define TAG_GPS_SPEED                   0x000D
#define TAG_GPS_TRACK_REF               0x000E
#define TAG_GPS_TRACK                   0x000F
#define TAG_GPS_IMG_DIRECTION_REF       0x0010
#define TAG_GPS_IMG_DIRECTION           0x0011
#define TAG_GPS_MAP_DATUM               0x0012
#define TAG_GPS_DEST_LATITUDE_REF       0x0013
#define TAG_GPS_DEST_LATITUDE           0x0014
#define TAG_GPS_DEST_LONGITUDE_REF      0x0015
#define TAG_GPS_DEST_LONGITUDE          0x0016
#define TAG_GPS_DEST_BEARING_REF        0x0017
#define TAG_GPS_DEST_BEARING            0x0018
#define TAG_GPS_DEST_DISTANCE_REF       0x0019
#define TAG_GPS_DEST_DISTANCE           0x001A
#define TAG_GPS_PROCESSING_METHOD       0x001B
#define TAG_GPS_AREA_INFORMATION        0x001C
#define TAG_GPS_DATE_STAMP              0x001D
#define TAG_GPS_DIFFERENTIAL            0x001E
#define TAG_TIFF_COMMENT                0x00FE /* SHOUDLNT HAPPEN */
#define TAG_NEW_SUBFILE                 0x00FE /* New version of subfile tag */
#define TAG_SUBFILE_TYPE                0x00FF /* Old version of subfile tag */
#define TAG_IMAGEWIDTH                  0x0100
#define TAG_IMAGEHEIGHT                 0x0101
#define TAG_BITS_PER_SAMPLE             0x0102
#define TAG_COMPRESSION                 0x0103
#define TAG_PHOTOMETRIC_INTERPRETATION  0x0106
#define TAG_TRESHHOLDING                0x0107
#define TAG_CELL_WIDTH                  0x0108
#define TAG_CELL_HEIGHT                 0x0109
#define TAG_FILL_ORDER                  0x010A
#define TAG_DOCUMENT_NAME               0x010D
#define TAG_IMAGE_DESCRIPTION           0x010E
#define TAG_MAKE                        0x010F
#define TAG_MODEL                       0x0110
#define TAG_STRIP_OFFSETS               0x0111
#define TAG_ORIENTATION                 0x0112
#define TAG_SAMPLES_PER_PIXEL           0x0115
#define TAG_ROWS_PER_STRIP              0x0116
#define TAG_STRIP_BYTE_COUNTS           0x0117
#define TAG_MIN_SAMPPLE_VALUE           0x0118
#define TAG_MAX_SAMPLE_VALUE            0x0119
#define TAG_X_RESOLUTION                0x011A
#define TAG_Y_RESOLUTION                0x011B
#define TAG_PLANAR_CONFIGURATION        0x011C
#define TAG_PAGE_NAME                   0x011D
#define TAG_X_POSITION                  0x011E
#define TAG_Y_POSITION                  0x011F
#define TAG_FREE_OFFSETS                0x0120
#define TAG_FREE_BYTE_COUNTS            0x0121
#define TAG_GRAY_RESPONSE_UNIT          0x0122
#define TAG_GRAY_RESPONSE_CURVE         0x0123
#define TAG_RESOLUTION_UNIT             0x0128
#define TAG_PAGE_NUMBER                 0x0129
#define TAG_TRANSFER_FUNCTION           0x012D
#define TAG_SOFTWARE                    0x0131
#define TAG_DATETIME                    0x0132
#define TAG_ARTIST                      0x013B
#define TAG_HOST_COMPUTER               0x013C
#define TAG_PREDICTOR                   0x013D
#define TAG_WHITE_POINT                 0x013E
#define TAG_PRIMARY_CHROMATICITIES      0x013F
#define TAG_COLOR_MAP                   0x0140
#define TAG_HALFTONE_HINTS              0x0141
#define TAG_TILE_WIDTH                  0x0142
#define TAG_TILE_LENGTH                 0x0143
#define TAG_TILE_OFFSETS                0x0144
#define TAG_TILE_BYTE_COUNTS            0x0145
#define TAG_SUB_IFD                     0x014A
#define TAG_INK_SETMPUTER               0x014C
#define TAG_INK_NAMES                   0x014D
#define TAG_NUMBER_OF_INKS              0x014E
#define TAG_DOT_RANGE                   0x0150
#define TAG_TARGET_PRINTER              0x0151
#define TAG_EXTRA_SAMPLE                0x0152
#define TAG_SAMPLE_FORMAT               0x0153
#define TAG_S_MIN_SAMPLE_VALUE          0x0154
#define TAG_S_MAX_SAMPLE_VALUE          0x0155
#define TAG_TRANSFER_RANGE              0x0156
#define TAG_JPEG_TABLES                 0x015B
#define TAG_JPEG_PROC                   0x0200
#define TAG_JPEG_INTERCHANGE_FORMAT     0x0201
#define TAG_JPEG_INTERCHANGE_FORMAT_LEN 0x0202
#define TAG_JPEG_RESTART_INTERVAL       0x0203
#define TAG_JPEG_LOSSLESS_PREDICTOR     0x0205
#define TAG_JPEG_POINT_TRANSFORMS       0x0206
#define TAG_JPEG_Q_TABLES               0x0207
#define TAG_JPEG_DC_TABLES              0x0208
#define TAG_JPEG_AC_TABLES              0x0209
#define TAG_YCC_COEFFICIENTS            0x0211
#define TAG_YCC_SUB_SAMPLING            0x0212
#define TAG_YCC_POSITIONING             0x0213
#define TAG_REFERENCE_BLACK_WHITE       0x0214
/* 0x0301 - 0x0302 */
/* 0x0320 */
/* 0x0343 */
/* 0x5001 - 0x501B */
/* 0x5021 - 0x503B */
/* 0x5090 - 0x5091 */
/* 0x5100 - 0x5101 */
/* 0x5110 - 0x5113 */
/* 0x80E3 - 0x80E6 */
/* 0x828d - 0x828F */
#define TAG_COPYRIGHT                   0x8298
#define TAG_EXPOSURETIME                0x829A
#define TAG_FNUMBER                     0x829D
#define TAG_EXIF_IFD_POINTER            0x8769
#define TAG_ICC_PROFILE                 0x8773
#define TAG_EXPOSURE_PROGRAM            0x8822
#define TAG_SPECTRAL_SENSITY            0x8824
#define TAG_GPS_IFD_POINTER             0x8825
#define TAG_ISOSPEED                    0x8827
#define TAG_OPTOELECTRIC_CONVERSION_F   0x8828
/* 0x8829 - 0x882b */
#define TAG_EXIFVERSION                 0x9000
#define TAG_DATE_TIME_ORIGINAL          0x9003
#define TAG_DATE_TIME_DIGITIZED         0x9004
#define TAG_COMPONENT_CONFIG            0x9101
#define TAG_COMPRESSED_BITS_PER_PIXEL   0x9102
#define TAG_SHUTTERSPEED                0x9201
#define TAG_APERTURE                    0x9202
#define TAG_BRIGHTNESS_VALUE            0x9203
#define TAG_EXPOSURE_BIAS_VALUE         0x9204
#define TAG_MAX_APERTURE                0x9205
#define TAG_SUBJECT_DISTANCE            0x9206
#define TAG_METRIC_MODULE               0x9207
#define TAG_LIGHT_SOURCE                0x9208
#define TAG_FLASH                       0x9209
#define TAG_FOCAL_LENGTH                0x920A
/* 0x920B - 0x920D */
/* 0x9211 - 0x9216 */
#define TAG_SUBJECT_AREA                0x9214
#define TAG_MAKER_NOTE                  0x927C
#define TAG_USERCOMMENT                 0x9286
#define TAG_SUB_SEC_TIME                0x9290
#define TAG_SUB_SEC_TIME_ORIGINAL       0x9291
#define TAG_SUB_SEC_TIME_DIGITIZED      0x9292
/* 0x923F */
/* 0x935C */
#define TAG_XP_TITLE                    0x9C9B
#define TAG_XP_COMMENTS                 0x9C9C
#define TAG_XP_AUTHOR                   0x9C9D
#define TAG_XP_KEYWORDS                 0x9C9E
#define TAG_XP_SUBJECT                  0x9C9F
#define TAG_FLASH_PIX_VERSION           0xA000
#define TAG_COLOR_SPACE                 0xA001
#define TAG_COMP_IMAGE_WIDTH            0xA002 /* compressed images only */
#define TAG_COMP_IMAGE_HEIGHT           0xA003
#define TAG_RELATED_SOUND_FILE          0xA004
#define TAG_INTEROP_IFD_POINTER         0xA005 /* IFD pointer */
#define TAG_FLASH_ENERGY                0xA20B
#define TAG_SPATIAL_FREQUENCY_RESPONSE  0xA20C
#define TAG_FOCALPLANE_X_RES            0xA20E
#define TAG_FOCALPLANE_Y_RES            0xA20F
#define TAG_FOCALPLANE_RESOLUTION_UNIT  0xA210
#define TAG_SUBJECT_LOCATION            0xA214
#define TAG_EXPOSURE_INDEX              0xA215
#define TAG_SENSING_METHOD              0xA217
#define TAG_FILE_SOURCE                 0xA300
#define TAG_SCENE_TYPE                  0xA301
#define TAG_CFA_PATTERN                 0xA302
#define TAG_CUSTOM_RENDERED             0xA401
#define TAG_EXPOSURE_MODE               0xA402
#define TAG_WHITE_BALANCE               0xA403
#define TAG_DIGITAL_ZOOM_RATIO          0xA404
#define TAG_FOCAL_LENGTH_IN_35_MM_FILM  0xA405
#define TAG_SCENE_CAPTURE_TYPE          0xA406
#define TAG_GAIN_CONTROL                0xA407
#define TAG_CONTRAST                    0xA408
#define TAG_SATURATION                  0xA409
#define TAG_SHARPNESS                   0xA40A
#define TAG_DEVICE_SETTING_DESCRIPTION  0xA40B
#define TAG_SUBJECT_DISTANCE_RANGE      0xA40C
#define TAG_IMAGE_UNIQUE_ID             0xA420

/* Olympus specific tags */
#define TAG_OLYMPUS_SPECIALMODE         0x0200
#define TAG_OLYMPUS_JPEGQUAL            0x0201
#define TAG_OLYMPUS_MACRO               0x0202
#define TAG_OLYMPUS_DIGIZOOM            0x0204
#define TAG_OLYMPUS_SOFTWARERELEASE     0x0207
#define TAG_OLYMPUS_PICTINFO            0x0208
#define TAG_OLYMPUS_CAMERAID            0x0209
/* end Olympus specific tags */

/* Internal */
#define TAG_NONE               			-1 /* note that -1 <> 0xFFFF */
#define TAG_COMPUTED_VALUE     			-2
#define TAG_END_OF_LIST                 0xFFFD

/* Values for TAG_PHOTOMETRIC_INTERPRETATION */
#define PMI_BLACK_IS_ZERO       0
#define PMI_WHITE_IS_ZERO       1
#define PMI_RGB          	    2
#define PMI_PALETTE_COLOR       3
#define PMI_TRANSPARENCY_MASK   4
#define PMI_SEPARATED           5
#define PMI_YCBCR               6
#define PMI_CIELAB              8

/* }}} */

/* {{{ TabTable[]
 */
typedef const struct {
	unsigned short Tag;
	char *Desc;
} tag_info_type;

typedef tag_info_type  tag_info_array[];
typedef tag_info_type  *tag_table_type;

#define TAG_TABLE_END \
  {TAG_NONE,           "No tag value"},\
  {TAG_COMPUTED_VALUE, "Computed value"},\
  {TAG_END_OF_LIST,    ""}  /* Important for exif_get_tagname() IF value != "" function result is != false */

static tag_info_array tag_table_IFD = {
  { 0x000B, "ACDComment"},
  { 0x00FE, "NewSubFile"}, /* better name it 'ImageType' ? */
  { 0x00FF, "SubFile"},
  { 0x0100, "ImageWidth"},
  { 0x0101, "ImageLength"},
  { 0x0102, "BitsPerSample"},
  { 0x0103, "Compression"},
  { 0x0106, "PhotometricInterpretation"},
  { 0x010A, "FillOrder"},
  { 0x010D, "DocumentName"},
  { 0x010E, "ImageDescription"},
  { 0x010F, "Make"},
  { 0x0110, "Model"},
  { 0x0111, "StripOffsets"},
  { 0x0112, "Orientation"},
  { 0x0115, "SamplesPerPixel"},
  { 0x0116, "RowsPerStrip"},
  { 0x0117, "StripByteCounts"},
  { 0x0118, "MinSampleValue"},
  { 0x0119, "MaxSampleValue"},
  { 0x011A, "XResolution"},
  { 0x011B, "YResolution"},
  { 0x011C, "PlanarConfiguration"},
  { 0x011D, "PageName"},
  { 0x011E, "XPosition"},
  { 0x011F, "YPosition"},
  { 0x0120, "FreeOffsets"},
  { 0x0121, "FreeByteCounts"},
  { 0x0122, "GrayResponseUnit"},
  { 0x0123, "GrayResponseCurve"},
  { 0x0124, "T4Options"},
  { 0x0125, "T6Options"},
  { 0x0128, "ResolutionUnit"},
  { 0x0129, "PageNumber"},
  { 0x012D, "TransferFunction"},
  { 0x0131, "Software"},
  { 0x0132, "DateTime"},
  { 0x013B, "Artist"},
  { 0x013C, "HostComputer"},
  { 0x013D, "Predictor"},
  { 0x013E, "WhitePoint"},
  { 0x013F, "PrimaryChromaticities"},
  { 0x0140, "ColorMap"},
  { 0x0141, "HalfToneHints"},
  { 0x0142, "TileWidth"},
  { 0x0143, "TileLength"},
  { 0x0144, "TileOffsets"},
  { 0x0145, "TileByteCounts"},
  { 0x014A, "SubIFD"},
  { 0x014C, "InkSet"},
  { 0x014D, "InkNames"},
  { 0x014E, "NumberOfInks"},
  { 0x0150, "DotRange"},
  { 0x0151, "TargetPrinter"},
  { 0x0152, "ExtraSample"},
  { 0x0153, "SampleFormat"},
  { 0x0154, "SMinSampleValue"},
  { 0x0155, "SMaxSampleValue"},
  { 0x0156, "TransferRange"},
  { 0x0157, "ClipPath"},
  { 0x0158, "XClipPathUnits"},
  { 0x0159, "YClipPathUnits"},
  { 0x015A, "Indexed"},
  { 0x015B, "JPEGTables"},
  { 0x015F, "OPIProxy"},
  { 0x0200, "JPEGProc"},
  { 0x0201, "JPEGInterchangeFormat"},
  { 0x0202, "JPEGInterchangeFormatLength"},
  { 0x0203, "JPEGRestartInterval"},
  { 0x0205, "JPEGLosslessPredictors"},
  { 0x0206, "JPEGPointTransforms"},
  { 0x0207, "JPEGQTables"},
  { 0x0208, "JPEGDCTables"},
  { 0x0209, "JPEGACTables"},
  { 0x0211, "YCbCrCoefficients"},
  { 0x0212, "YCbCrSubSampling"},
  { 0x0213, "YCbCrPositioning"},
  { 0x0214, "ReferenceBlackWhite"},
  { 0x02BC, "ExtensibleMetadataPlatform"}, /* XAP: Extensible Authoring Publishing, obsoleted by XMP: Extensible Metadata Platform */
  { 0x0301, "Gamma"},
  { 0x0302, "ICCProfileDescriptor"},
  { 0x0303, "SRGBRenderingIntent"},
  { 0x0320, "ImageTitle"},
  { 0x5001, "ResolutionXUnit"},
  { 0x5002, "ResolutionYUnit"},
  { 0x5003, "ResolutionXLengthUnit"},
  { 0x5004, "ResolutionYLengthUnit"},
  { 0x5005, "PrintFlags"},
  { 0x5006, "PrintFlagsVersion"},
  { 0x5007, "PrintFlagsCrop"},
  { 0x5008, "PrintFlagsBleedWidth"},
  { 0x5009, "PrintFlagsBleedWidthScale"},
  { 0x500A, "HalftoneLPI"},
  { 0x500B, "HalftoneLPIUnit"},
  { 0x500C, "HalftoneDegree"},
  { 0x500D, "HalftoneShape"},
  { 0x500E, "HalftoneMisc"},
  { 0x500F, "HalftoneScreen"},
  { 0x5010, "JPEGQuality"},
  { 0x5011, "GridSize"},
  { 0x5012, "ThumbnailFormat"},
  { 0x5013, "ThumbnailWidth"},
  { 0x5014, "ThumbnailHeight"},
  { 0x5015, "ThumbnailColorDepth"},
  { 0x5016, "ThumbnailPlanes"},
  { 0x5017, "ThumbnailRawBytes"},
  { 0x5018, "ThumbnailSize"},
  { 0x5019, "ThumbnailCompressedSize"},
  { 0x501A, "ColorTransferFunction"},
  { 0x501B, "ThumbnailData"},
  { 0x5020, "ThumbnailImageWidth"},
  { 0x5021, "ThumbnailImageHeight"},
  { 0x5022, "ThumbnailBitsPerSample"},
  { 0x5023, "ThumbnailCompression"},
  { 0x5024, "ThumbnailPhotometricInterp"},
  { 0x5025, "ThumbnailImageDescription"},
  { 0x5026, "ThumbnailEquipMake"},
  { 0x5027, "ThumbnailEquipModel"},
  { 0x5028, "ThumbnailStripOffsets"},
  { 0x5029, "ThumbnailOrientation"},
  { 0x502A, "ThumbnailSamplesPerPixel"},
  { 0x502B, "ThumbnailRowsPerStrip"},
  { 0x502C, "ThumbnailStripBytesCount"},
  { 0x502D, "ThumbnailResolutionX"},
  { 0x502E, "ThumbnailResolutionY"},
  { 0x502F, "ThumbnailPlanarConfig"},
  { 0x5030, "ThumbnailResolutionUnit"},
  { 0x5031, "ThumbnailTransferFunction"},
  { 0x5032, "ThumbnailSoftwareUsed"},
  { 0x5033, "ThumbnailDateTime"},
  { 0x5034, "ThumbnailArtist"},
  { 0x5035, "ThumbnailWhitePoint"},
  { 0x5036, "ThumbnailPrimaryChromaticities"},
  { 0x5037, "ThumbnailYCbCrCoefficients"},
  { 0x5038, "ThumbnailYCbCrSubsampling"},
  { 0x5039, "ThumbnailYCbCrPositioning"},
  { 0x503A, "ThumbnailRefBlackWhite"},
  { 0x503B, "ThumbnailCopyRight"},
  { 0x5090, "LuminanceTable"},
  { 0x5091, "ChrominanceTable"},
  { 0x5100, "FrameDelay"},
  { 0x5101, "LoopCount"},
  { 0x5110, "PixelUnit"},
  { 0x5111, "PixelPerUnitX"},
  { 0x5112, "PixelPerUnitY"},
  { 0x5113, "PaletteHistogram"},
  { 0x1000, "RelatedImageFileFormat"},
  { 0x800D, "ImageID"},
  { 0x80E3, "Matteing"},   /* obsoleted by ExtraSamples */
  { 0x80E4, "DataType"},   /* obsoleted by SampleFormat */
  { 0x80E5, "ImageDepth"},
  { 0x80E6, "TileDepth"},
  { 0x828D, "CFARepeatPatternDim"},
  { 0x828E, "CFAPattern"},
  { 0x828F, "BatteryLevel"},
  { 0x8298, "Copyright"},
  { 0x829A, "ExposureTime"},
  { 0x829D, "FNumber"},
  { 0x83BB, "IPTC/NAA"},
  { 0x84E3, "IT8RasterPadding"},
  { 0x84E5, "IT8ColorTable"},
  { 0x8649, "ImageResourceInformation"}, /* PhotoShop */
  { 0x8769, "Exif_IFD_Pointer"},
  { 0x8773, "ICC_Profile"},
  { 0x8822, "ExposureProgram"},
  { 0x8824, "SpectralSensity"},
  { 0x8828, "OECF"},
  { 0x8825, "GPS_IFD_Pointer"},
  { 0x8827, "ISOSpeedRatings"},
  { 0x8828, "OECF"},
  { 0x9000, "ExifVersion"},
  { 0x9003, "DateTimeOriginal"},
  { 0x9004, "DateTimeDigitized"},
  { 0x9101, "ComponentsConfiguration"},
  { 0x9102, "CompressedBitsPerPixel"},
  { 0x9201, "ShutterSpeedValue"},
  { 0x9202, "ApertureValue"},
  { 0x9203, "BrightnessValue"},
  { 0x9204, "ExposureBiasValue"},
  { 0x9205, "MaxApertureValue"},
  { 0x9206, "SubjectDistance"},
  { 0x9207, "MeteringMode"},
  { 0x9208, "LightSource"},
  { 0x9209, "Flash"},
  { 0x920A, "FocalLength"},
  { 0x920B, "FlashEnergy"},                 /* 0xA20B  in JPEG   */
  { 0x920C, "SpatialFrequencyResponse"},    /* 0xA20C    -  -    */
  { 0x920D, "Noise"},
  { 0x920E, "FocalPlaneXResolution"},       /* 0xA20E    -  -    */
  { 0x920F, "FocalPlaneYResolution"},       /* 0xA20F    -  -    */
  { 0x9210, "FocalPlaneResolutionUnit"},    /* 0xA210    -  -    */
  { 0x9211, "ImageNumber"},
  { 0x9212, "SecurityClassification"},
  { 0x9213, "ImageHistory"},
  { 0x9214, "SubjectLocation"},             /* 0xA214    -  -    */
  { 0x9215, "ExposureIndex"},               /* 0xA215    -  -    */
  { 0x9216, "TIFF/EPStandardID"},
  { 0x9217, "SensingMethod"},               /* 0xA217    -  -    */
  { 0x923F, "StoNits"},
  { 0x927C, "MakerNote"},
  { 0x9286, "UserComment"},
  { 0x9290, "SubSecTime"},
  { 0x9291, "SubSecTimeOriginal"},
  { 0x9292, "SubSecTimeDigitized"},
  { 0x935C, "ImageSourceData"},             /* "Adobe Photoshop Document Data Block": 8BIM... */
  { 0x9c9b, "Title" },                      /* Win XP specific, Unicode  */
  { 0x9c9c, "Comments" },                   /* Win XP specific, Unicode  */
  { 0x9c9d, "Author" },                     /* Win XP specific, Unicode  */
  { 0x9c9e, "Keywords" },                   /* Win XP specific, Unicode  */
  { 0x9c9f, "Subject" },                    /* Win XP specific, Unicode, not to be confused with SubjectDistance and SubjectLocation */
  { 0xA000, "FlashPixVersion"},
  { 0xA001, "ColorSpace"},
  { 0xA002, "ExifImageWidth"},
  { 0xA003, "ExifImageLength"},
  { 0xA004, "RelatedSoundFile"},
  { 0xA005, "InteroperabilityOffset"},
  { 0xA20B, "FlashEnergy"},                 /* 0x920B in TIFF/EP */
  { 0xA20C, "SpatialFrequencyResponse"},    /* 0x920C    -  -    */
  { 0xA20D, "Noise"},
  { 0xA20E, "FocalPlaneXResolution"},    	/* 0x920E    -  -    */
  { 0xA20F, "FocalPlaneYResolution"},       /* 0x920F    -  -    */
  { 0xA210, "FocalPlaneResolutionUnit"},    /* 0x9210    -  -    */
  { 0xA211, "ImageNumber"},
  { 0xA212, "SecurityClassification"},
  { 0xA213, "ImageHistory"},
  { 0xA214, "SubjectLocation"},             /* 0x9214    -  -    */
  { 0xA215, "ExposureIndex"},               /* 0x9215    -  -    */
  { 0xA216, "TIFF/EPStandardID"},
  { 0xA217, "SensingMethod"},               /* 0x9217    -  -    */
  { 0xA300, "FileSource"},
  { 0xA301, "SceneType"},
  { 0xA302, "CFAPattern"},
  { 0xA401, "CustomRendered"},
  { 0xA402, "ExposureMode"},
  { 0xA403, "WhiteBalance"},
  { 0xA404, "DigitalZoomRatio"},
  { 0xA405, "FocalLengthIn35mmFilm"},
  { 0xA406, "SceneCaptureType"},
  { 0xA407, "GainControl"},
  { 0xA408, "Contrast"},
  { 0xA409, "Saturation"},
  { 0xA40A, "Sharpness"},
  { 0xA40B, "DeviceSettingDescription"},
  { 0xA40C, "SubjectDistanceRange"},
  { 0xA420, "ImageUniqueID"},
  TAG_TABLE_END
} ;

static tag_info_array tag_table_GPS = {
  { 0x0000, "GPSVersion"},
  { 0x0001, "GPSLatitudeRef"},
  { 0x0002, "GPSLatitude"},
  { 0x0003, "GPSLongitudeRef"},
  { 0x0004, "GPSLongitude"},
  { 0x0005, "GPSAltitudeRef"},
  { 0x0006, "GPSAltitude"},
  { 0x0007, "GPSTimeStamp"},
  { 0x0008, "GPSSatellites"},
  { 0x0009, "GPSStatus"},
  { 0x000A, "GPSMeasureMode"},
  { 0x000B, "GPSDOP"},
  { 0x000C, "GPSSpeedRef"},
  { 0x000D, "GPSSpeed"},
  { 0x000E, "GPSTrackRef"},
  { 0x000F, "GPSTrack"},
  { 0x0010, "GPSImgDirectionRef"},
  { 0x0011, "GPSImgDirection"},
  { 0x0012, "GPSMapDatum"},
  { 0x0013, "GPSDestLatitudeRef"},
  { 0x0014, "GPSDestLatitude"},
  { 0x0015, "GPSDestLongitudeRef"},
  { 0x0016, "GPSDestLongitude"},
  { 0x0017, "GPSDestBearingRef"},
  { 0x0018, "GPSDestBearing"},
  { 0x0019, "GPSDestDistanceRef"},
  { 0x001A, "GPSDestDistance"},
  { 0x001B, "GPSProcessingMode"},
  { 0x001C, "GPSAreaInformation"},
  { 0x001D, "GPSDateStamp"},
  { 0x001E, "GPSDifferential"},
  TAG_TABLE_END
};

static tag_info_array tag_table_IOP = {
  { 0x0001, "InterOperabilityIndex"}, /* should be 'R98' or 'THM' */
  { 0x0002, "InterOperabilityVersion"},
  { 0x1000, "RelatedFileFormat"},
  { 0x1001, "RelatedImageWidth"},
  { 0x1002, "RelatedImageHeight"},
  TAG_TABLE_END
};

static tag_info_array tag_table_VND_CANON = {
  { 0x0001, "ModeArray"}, /* guess */
  { 0x0004, "ImageInfo"}, /* guess */
  { 0x0006, "ImageType"},
  { 0x0007, "FirmwareVersion"},
  { 0x0008, "ImageNumber"},
  { 0x0009, "OwnerName"},
  { 0x000C, "Camera"},
  { 0x000F, "CustomFunctions"},
  TAG_TABLE_END
};

static tag_info_array tag_table_VND_CASIO = {
  { 0x0001, "RecordingMode"},
  { 0x0002, "Quality"},
  { 0x0003, "FocusingMode"},
  { 0x0004, "FlashMode"},
  { 0x0005, "FlashIntensity"},
  { 0x0006, "ObjectDistance"},
  { 0x0007, "WhiteBalance"},
  { 0x000A, "DigitalZoom"},
  { 0x000B, "Sharpness"},
  { 0x000C, "Contrast"},
  { 0x000D, "Saturation"},
  { 0x0014, "CCDSensitivity"},
  TAG_TABLE_END
};

static tag_info_array tag_table_VND_FUJI = {
  { 0x0000, "Version"},
  { 0x1000, "Quality"},
  { 0x1001, "Sharpness"},
  { 0x1002, "WhiteBalance"},
  { 0x1003, "Color"},
  { 0x1004, "Tone"},
  { 0x1010, "FlashMode"},
  { 0x1011, "FlashStrength"},
  { 0x1020, "Macro"},
  { 0x1021, "FocusMode"},
  { 0x1030, "SlowSync"},
  { 0x1031, "PictureMode"},
  { 0x1100, "ContTake"},
  { 0x1300, "BlurWarning"},
  { 0x1301, "FocusWarning"},
  { 0x1302, "AEWarning "},
  TAG_TABLE_END
};

static tag_info_array tag_table_VND_NIKON = {
  { 0x0003, "Quality"},
  { 0x0004, "ColorMode"},
  { 0x0005, "ImageAdjustment"},
  { 0x0006, "CCDSensitivity"},
  { 0x0007, "WhiteBalance"},
  { 0x0008, "Focus"},
  { 0x000a, "DigitalZoom"},
  { 0x000b, "Converter"},
  TAG_TABLE_END
};

static tag_info_array tag_table_VND_NIKON_990 = {
  { 0x0001, "Version"},
  { 0x0002, "ISOSetting"},
  { 0x0003, "ColorMode"},
  { 0x0004, "Quality"},
  { 0x0005, "WhiteBalance"},
  { 0x0006, "ImageSharpening"},
  { 0x0007, "FocusMode"},
  { 0x0008, "FlashSetting"},
  { 0x000F, "ISOSelection"},
  { 0x0080, "ImageAdjustment"},
  { 0x0082, "AuxiliaryLens"},
  { 0x0085, "ManualFocusDistance"},
  { 0x0086, "DigitalZoom"},
  { 0x0088, "AFFocusPosition"},
  { 0x0010, "DataDump"},
  TAG_TABLE_END
};

static tag_info_array tag_table_VND_OLYMPUS = {
  { 0x0200, "SpecialMode"},
  { 0x0201, "JPEGQuality"},
  { 0x0202, "Macro"},
  { 0x0204, "DigitalZoom"},
  { 0x0207, "SoftwareRelease"},
  { 0x0208, "PictureInfo"},
  { 0x0209, "CameraId"},
  { 0x0F00, "DataDump"},
  TAG_TABLE_END
};

typedef enum mn_byte_order_t {
	MN_ORDER_INTEL    = 0,
	MN_ORDER_MOTOROLA = 1,
	MN_ORDER_NORMAL
} mn_byte_order_t;

typedef enum mn_offset_mode_t {
	MN_OFFSET_NORMAL,
	MN_OFFSET_MAKER,
	MN_OFFSET_GUESS
} mn_offset_mode_t;

typedef struct {
	tag_table_type   tag_table;
	char *           make;
	char *           model;
	char *           id_string;
	int              id_string_len;
	int              offset;
	mn_byte_order_t  byte_order;
	mn_offset_mode_t offset_mode;
} maker_note_type;

static const maker_note_type maker_note_array[] = {
  { tag_table_VND_CANON,     "Canon",                   NULL,  NULL,                       0,  0,  MN_ORDER_INTEL,    MN_OFFSET_GUESS},
/*  { tag_table_VND_CANON,     "Canon",                   NULL,  NULL,                       0,  0,  MN_ORDER_NORMAL,   MN_OFFSET_NORMAL},*/
  { tag_table_VND_CASIO,     "CASIO",                   NULL,  NULL,                       0,  0,  MN_ORDER_MOTOROLA, MN_OFFSET_NORMAL},
  { tag_table_VND_FUJI,      "FUJIFILM",                NULL,  "FUJIFILM\x0C\x00\x00\x00", 12, 12, MN_ORDER_INTEL,    MN_OFFSET_MAKER},
  { tag_table_VND_NIKON,     "NIKON",                   NULL,  "Nikon\x00\x01\x00",        8,  8,  MN_ORDER_NORMAL,   MN_OFFSET_NORMAL},
  { tag_table_VND_NIKON_990, "NIKON",                   NULL,  NULL,                       0,  0,  MN_ORDER_NORMAL,   MN_OFFSET_NORMAL},
  { tag_table_VND_OLYMPUS,   "OLYMPUS OPTICAL CO.,LTD", NULL,  "OLYMP\x00\x01\x00",        8,  8,  MN_ORDER_NORMAL,   MN_OFFSET_NORMAL},
};
/* }}} */

/* {{{ exif_get_tagname
	Get headername for tag_num or NULL if not defined */
static char * exif_get_tagname(int tag_num, char *ret, int len, tag_table_type tag_table)
{
	int i, t;
	char tmp[32];

	for (i = 0; (t = tag_table[i].Tag) != TAG_END_OF_LIST; i++) {
		if (t == tag_num) {