libextractor

extractor.h (31602B)

---

 /*
      This file is part of libextractor.
      Copyright (C) 2002-2017 Vidyut Samanta and 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.
  */
 
 #ifndef EXTRACTOR_H
 #define EXTRACTOR_H
 
 #ifdef __cplusplus
 extern "C" {
 #if 0 /* keep Emacsens' auto-indent happy */
 }
 #endif
 #endif
 
 
 #include <stdint.h>
 
 /**
  * 0.2.6-1 => 0x00020601
  * 4.5.2-0 => 0x04050200
  */
 #define EXTRACTOR_VERSION 0x01120000
 
 #include <stdio.h>
 
 #ifndef _EXTRACTOR_EXTERN
 #if defined(_WIN32) && defined(MHD_W32LIB)
 #define _EXTRACTOR_EXTERN extern
 #elif defined (_WIN32) && defined(MHD_W32DLL)
 /* Define MHD_W32DLL when using MHD as W32 .DLL to speed up linker a little */
 #define _EXTRACTOR_EXTERN __declspec(dllimport)
 #else
 #define _EXTRACTOR_EXTERN extern
 #endif
 #endif
 
 /**
  * Options for how plugin execution should be done.
  */
 enum EXTRACTOR_Options
 {
 
   /**
    * Run plugin out-of-process, starting the process once the plugin
    * is to be run.  If a plugin crashes, automatically restart the
    * respective process for the same file and try once more
    * (since the crash may be caused by the previous file).  If
    * the process crashes immediately again, it is not restarted
    * until the next file.
    */
   EXTRACTOR_OPTION_DEFAULT_POLICY = 0,
 
   /**
    * Deprecated option.  Ignored.
    */
   EXTRACTOR_OPTION_OUT_OF_PROCESS_NO_RESTART = 1,
 
   /**
    * Run plugins in-process.  Unsafe, not recommended,
    * can be nice for debugging.
    */
   EXTRACTOR_OPTION_IN_PROCESS = 2,
 
   /**
    * Internal value for plugins that have been disabled.
    */
   EXTRACTOR_OPTION_DISABLED = 3
 
 };
 
 
 /**
  * Format in which the extracted meta data is presented.
  */
 enum EXTRACTOR_MetaFormat
 {
   /**
    * Format is unknown.
    */
   EXTRACTOR_METAFORMAT_UNKNOWN = 0,
 
   /**
    * 0-terminated, UTF-8 encoded string.  "data_len"
    * is strlen(data)+1.
    */
   EXTRACTOR_METAFORMAT_UTF8 = 1,
 
   /**
    * Some kind of binary format, see given Mime type.
    */
   EXTRACTOR_METAFORMAT_BINARY = 2,
 
   /**
    * 0-terminated string.  The specific encoding is unknown.
    * "data_len" is strlen (data)+1.
    */
   EXTRACTOR_METAFORMAT_C_STRING = 3
 
 };
 
 
 /**
  * Enumeration defining various sources of keywords.  See also
  * http://dublincore.org/documents/1998/09/dces/
  *
  * @defgroup types meta data types
  * @{
  */
 enum EXTRACTOR_MetaType
 {
   /* available to application for marking an `enum EXTRACTOR_MetaType` as not
      carrying any meaningful value - never used by libextractor */
   EXTRACTOR_METATYPE_NONE = -1,
 
   /* reserved should be used as a terminator (like the '\0'-terminator for strings)
      and is never used directly by libextractor */
   EXTRACTOR_METATYPE_RESERVED = 0,
 
   EXTRACTOR_METATYPE_MIMETYPE = 1,
   EXTRACTOR_METATYPE_FILENAME = 2,
   EXTRACTOR_METATYPE_COMMENT = 3,
 
   /* Standard types from bibtex */
   EXTRACTOR_METATYPE_TITLE = 4,
   EXTRACTOR_METATYPE_BOOK_TITLE = 5,
   EXTRACTOR_METATYPE_BOOK_EDITION = 6,
   EXTRACTOR_METATYPE_BOOK_CHAPTER_NUMBER = 7,
   EXTRACTOR_METATYPE_JOURNAL_NAME = 8,
   EXTRACTOR_METATYPE_JOURNAL_VOLUME = 9,
   EXTRACTOR_METATYPE_JOURNAL_NUMBER = 10,
   EXTRACTOR_METATYPE_PAGE_COUNT = 11,
   EXTRACTOR_METATYPE_PAGE_RANGE = 12,
   EXTRACTOR_METATYPE_AUTHOR_NAME = 13,
   EXTRACTOR_METATYPE_AUTHOR_EMAIL = 14,
   EXTRACTOR_METATYPE_AUTHOR_INSTITUTION = 15,
   EXTRACTOR_METATYPE_PUBLISHER = 16,
   EXTRACTOR_METATYPE_PUBLISHER_ADDRESS = 17,
   EXTRACTOR_METATYPE_PUBLISHER_INSTITUTION = 18,
   EXTRACTOR_METATYPE_PUBLISHER_SERIES = 19,
   EXTRACTOR_METATYPE_PUBLICATION_TYPE = 20,
   EXTRACTOR_METATYPE_PUBLICATION_YEAR = 21,
   EXTRACTOR_METATYPE_PUBLICATION_MONTH = 22,
   EXTRACTOR_METATYPE_PUBLICATION_DAY = 23,
   EXTRACTOR_METATYPE_PUBLICATION_DATE = 24,
   EXTRACTOR_METATYPE_BIBTEX_EPRINT = 25,
   EXTRACTOR_METATYPE_BIBTEX_ENTRY_TYPE = 26,
   EXTRACTOR_METATYPE_LANGUAGE = 27,
   EXTRACTOR_METATYPE_CREATION_TIME = 28,
   EXTRACTOR_METATYPE_URL = 29,
 
   /* "unique" document identifiers */
   EXTRACTOR_METATYPE_URI = 30,
   EXTRACTOR_METATYPE_ISRC = 31,
   EXTRACTOR_METATYPE_HASH_MD4 = 32,
   EXTRACTOR_METATYPE_HASH_MD5 = 33,
   EXTRACTOR_METATYPE_HASH_SHA0 = 34,
   EXTRACTOR_METATYPE_HASH_SHA1 = 35,
   EXTRACTOR_METATYPE_HASH_RMD160 = 36,
 
   /* identifiers of a location */
   EXTRACTOR_METATYPE_GPS_LATITUDE_REF = 37,
   EXTRACTOR_METATYPE_GPS_LATITUDE = 38,
   EXTRACTOR_METATYPE_GPS_LONGITUDE_REF = 39,
   EXTRACTOR_METATYPE_GPS_LONGITUDE = 40,
   EXTRACTOR_METATYPE_LOCATION_CITY = 41,
   EXTRACTOR_METATYPE_LOCATION_SUBLOCATION = 42,
   EXTRACTOR_METATYPE_LOCATION_COUNTRY = 43,
   EXTRACTOR_METATYPE_LOCATION_COUNTRY_CODE = 44,
 
   /* generic attributes */
   EXTRACTOR_METATYPE_UNKNOWN = 45,
   EXTRACTOR_METATYPE_DESCRIPTION = 46,
   EXTRACTOR_METATYPE_COPYRIGHT = 47,
   EXTRACTOR_METATYPE_RIGHTS = 48,
   EXTRACTOR_METATYPE_KEYWORDS = 49,
   EXTRACTOR_METATYPE_ABSTRACT = 50,
   EXTRACTOR_METATYPE_SUMMARY = 51,
   EXTRACTOR_METATYPE_SUBJECT = 52,
   EXTRACTOR_METATYPE_CREATOR = 53,
   EXTRACTOR_METATYPE_FORMAT = 54,
   EXTRACTOR_METATYPE_FORMAT_VERSION = 55,
 
   /* processing history */
   EXTRACTOR_METATYPE_CREATED_BY_SOFTWARE = 56,
   EXTRACTOR_METATYPE_UNKNOWN_DATE = 57,
   EXTRACTOR_METATYPE_CREATION_DATE = 58,
   EXTRACTOR_METATYPE_MODIFICATION_DATE = 59,
   EXTRACTOR_METATYPE_LAST_PRINTED = 60,
   EXTRACTOR_METATYPE_LAST_SAVED_BY = 61,
   EXTRACTOR_METATYPE_TOTAL_EDITING_TIME = 62,
   EXTRACTOR_METATYPE_EDITING_CYCLES = 63,
   EXTRACTOR_METATYPE_MODIFIED_BY_SOFTWARE = 64,
   EXTRACTOR_METATYPE_REVISION_HISTORY = 65,
 
   EXTRACTOR_METATYPE_EMBEDDED_FILE_SIZE = 66,
   EXTRACTOR_METATYPE_FINDER_FILE_TYPE = 67,
   EXTRACTOR_METATYPE_FINDER_FILE_CREATOR = 68,
 
   /* software package specifics (deb, rpm, tgz, elf) */
   EXTRACTOR_METATYPE_PACKAGE_NAME = 69,
   EXTRACTOR_METATYPE_PACKAGE_VERSION = 70,
   EXTRACTOR_METATYPE_SECTION = 71,
   EXTRACTOR_METATYPE_UPLOAD_PRIORITY = 72,
   EXTRACTOR_METATYPE_PACKAGE_DEPENDENCY = 73,
   EXTRACTOR_METATYPE_PACKAGE_CONFLICTS = 74,
   EXTRACTOR_METATYPE_PACKAGE_REPLACES = 75,
   EXTRACTOR_METATYPE_PACKAGE_PROVIDES = 76,
   EXTRACTOR_METATYPE_PACKAGE_RECOMMENDS = 77,
   EXTRACTOR_METATYPE_PACKAGE_SUGGESTS = 78,
   EXTRACTOR_METATYPE_PACKAGE_MAINTAINER = 79,
   EXTRACTOR_METATYPE_PACKAGE_INSTALLED_SIZE = 80,
   EXTRACTOR_METATYPE_PACKAGE_SOURCE = 81,
   EXTRACTOR_METATYPE_PACKAGE_ESSENTIAL = 82,
   EXTRACTOR_METATYPE_TARGET_ARCHITECTURE = 83,
   EXTRACTOR_METATYPE_PACKAGE_PRE_DEPENDENCY = 84,
   EXTRACTOR_METATYPE_LICENSE = 85,
   EXTRACTOR_METATYPE_PACKAGE_DISTRIBUTION = 86,
   EXTRACTOR_METATYPE_BUILDHOST = 87,
   EXTRACTOR_METATYPE_VENDOR = 88,
   EXTRACTOR_METATYPE_TARGET_OS = 89,
   EXTRACTOR_METATYPE_SOFTWARE_VERSION = 90,
   EXTRACTOR_METATYPE_TARGET_PLATFORM = 91,
   EXTRACTOR_METATYPE_RESOURCE_TYPE = 92,
   EXTRACTOR_METATYPE_LIBRARY_SEARCH_PATH = 93,
   EXTRACTOR_METATYPE_LIBRARY_DEPENDENCY = 94,
 
   /* photography specifics */
   EXTRACTOR_METATYPE_CAMERA_MAKE = 95,
   EXTRACTOR_METATYPE_CAMERA_MODEL = 96,
   EXTRACTOR_METATYPE_EXPOSURE = 97,
   EXTRACTOR_METATYPE_APERTURE = 98,
   EXTRACTOR_METATYPE_EXPOSURE_BIAS = 99,
   EXTRACTOR_METATYPE_FLASH = 100,
   EXTRACTOR_METATYPE_FLASH_BIAS = 101,
   EXTRACTOR_METATYPE_FOCAL_LENGTH = 102,
   EXTRACTOR_METATYPE_FOCAL_LENGTH_35MM = 103,
   EXTRACTOR_METATYPE_ISO_SPEED = 104,
   EXTRACTOR_METATYPE_EXPOSURE_MODE = 105,
   EXTRACTOR_METATYPE_METERING_MODE = 106,
   EXTRACTOR_METATYPE_MACRO_MODE = 107,
   EXTRACTOR_METATYPE_IMAGE_QUALITY = 108,
   EXTRACTOR_METATYPE_WHITE_BALANCE = 109,
   EXTRACTOR_METATYPE_ORIENTATION = 110,
   EXTRACTOR_METATYPE_MAGNIFICATION = 111,
 
   /* image specifics */
   EXTRACTOR_METATYPE_IMAGE_DIMENSIONS = 112,
   EXTRACTOR_METATYPE_PRODUCED_BY_SOFTWARE = 113,
   EXTRACTOR_METATYPE_THUMBNAIL = 114,
   EXTRACTOR_METATYPE_IMAGE_RESOLUTION = 115,
   EXTRACTOR_METATYPE_SOURCE = 116,
 
   /* (text) document processing specifics */
   EXTRACTOR_METATYPE_CHARACTER_SET = 117,
   EXTRACTOR_METATYPE_LINE_COUNT = 118,
   EXTRACTOR_METATYPE_PARAGRAPH_COUNT = 119,
   EXTRACTOR_METATYPE_WORD_COUNT = 120,
   EXTRACTOR_METATYPE_CHARACTER_COUNT = 121,
   EXTRACTOR_METATYPE_PAGE_ORIENTATION = 122,
   EXTRACTOR_METATYPE_PAPER_SIZE = 123,
   EXTRACTOR_METATYPE_TEMPLATE = 124,
   EXTRACTOR_METATYPE_COMPANY = 125,
   EXTRACTOR_METATYPE_MANAGER = 126,
   EXTRACTOR_METATYPE_REVISION_NUMBER = 127,
 
   /* music / video specifics */
   EXTRACTOR_METATYPE_DURATION = 128,
   EXTRACTOR_METATYPE_ALBUM = 129,
   EXTRACTOR_METATYPE_ARTIST = 130,
   EXTRACTOR_METATYPE_GENRE = 131,
   EXTRACTOR_METATYPE_TRACK_NUMBER = 132,
   EXTRACTOR_METATYPE_DISC_NUMBER = 133,
   EXTRACTOR_METATYPE_PERFORMER = 134,
   EXTRACTOR_METATYPE_CONTACT_INFORMATION = 135,
   EXTRACTOR_METATYPE_SONG_VERSION = 136,
   EXTRACTOR_METATYPE_PICTURE = 137,
   EXTRACTOR_METATYPE_COVER_PICTURE = 138,
   EXTRACTOR_METATYPE_CONTRIBUTOR_PICTURE = 139,
   EXTRACTOR_METATYPE_EVENT_PICTURE = 140,
   EXTRACTOR_METATYPE_LOGO = 141,
   EXTRACTOR_METATYPE_BROADCAST_TELEVISION_SYSTEM = 142,
   EXTRACTOR_METATYPE_SOURCE_DEVICE = 143,
   EXTRACTOR_METATYPE_DISCLAIMER = 144,
   EXTRACTOR_METATYPE_WARNING = 145,
   EXTRACTOR_METATYPE_PAGE_ORDER = 146,
   EXTRACTOR_METATYPE_WRITER = 147,
   EXTRACTOR_METATYPE_PRODUCT_VERSION = 148,
   EXTRACTOR_METATYPE_CONTRIBUTOR_NAME = 149,
   EXTRACTOR_METATYPE_MOVIE_DIRECTOR = 150,
   EXTRACTOR_METATYPE_NETWORK_NAME = 151,
   EXTRACTOR_METATYPE_SHOW_NAME = 152,
   EXTRACTOR_METATYPE_CHAPTER_NAME = 153,
   EXTRACTOR_METATYPE_SONG_COUNT = 154,
   EXTRACTOR_METATYPE_STARTING_SONG = 155,
   EXTRACTOR_METATYPE_PLAY_COUNTER = 156,
   EXTRACTOR_METATYPE_CONDUCTOR = 157,
   EXTRACTOR_METATYPE_INTERPRETATION = 158,
   EXTRACTOR_METATYPE_COMPOSER = 159,
   EXTRACTOR_METATYPE_BEATS_PER_MINUTE = 160,
   EXTRACTOR_METATYPE_ENCODED_BY = 161,
   EXTRACTOR_METATYPE_ORIGINAL_TITLE = 162,
   EXTRACTOR_METATYPE_ORIGINAL_ARTIST = 163,
   EXTRACTOR_METATYPE_ORIGINAL_WRITER = 164,
   EXTRACTOR_METATYPE_ORIGINAL_RELEASE_YEAR = 165,
   EXTRACTOR_METATYPE_ORIGINAL_PERFORMER = 166,
   EXTRACTOR_METATYPE_LYRICS = 167,
   EXTRACTOR_METATYPE_POPULARITY_METER = 168,
   EXTRACTOR_METATYPE_LICENSEE = 169,
   EXTRACTOR_METATYPE_MUSICIAN_CREDITS_LIST = 170,
   EXTRACTOR_METATYPE_MOOD = 171,
   EXTRACTOR_METATYPE_SUBTITLE = 172,
 
   /* GNUnet specific values (never extracted) */
   EXTRACTOR_METATYPE_GNUNET_DISPLAY_TYPE = 173,
   EXTRACTOR_METATYPE_GNUNET_FULL_DATA = 174,
   EXTRACTOR_METATYPE_RATING = 175,
   EXTRACTOR_METATYPE_ORGANIZATION = 176,
   EXTRACTOR_METATYPE_RIPPER = 177,
   EXTRACTOR_METATYPE_PRODUCER = 178,
   EXTRACTOR_METATYPE_GROUP = 179,
   EXTRACTOR_METATYPE_GNUNET_ORIGINAL_FILENAME = 180,
 
   EXTRACTOR_METATYPE_DISC_COUNT = 181,
 
   EXTRACTOR_METATYPE_CODEC = 182,
   EXTRACTOR_METATYPE_VIDEO_CODEC = 183,
   EXTRACTOR_METATYPE_AUDIO_CODEC = 184,
   EXTRACTOR_METATYPE_SUBTITLE_CODEC = 185,
 
   EXTRACTOR_METATYPE_CONTAINER_FORMAT = 186,
 
   EXTRACTOR_METATYPE_BITRATE = 187,
   EXTRACTOR_METATYPE_NOMINAL_BITRATE = 188,
   EXTRACTOR_METATYPE_MINIMUM_BITRATE = 189,
   EXTRACTOR_METATYPE_MAXIMUM_BITRATE = 190,
 
   EXTRACTOR_METATYPE_SERIAL = 191,
 
   EXTRACTOR_METATYPE_ENCODER = 192,
   EXTRACTOR_METATYPE_ENCODER_VERSION = 193,
 
   EXTRACTOR_METATYPE_TRACK_GAIN = 194,
   EXTRACTOR_METATYPE_TRACK_PEAK = 195,
   EXTRACTOR_METATYPE_ALBUM_GAIN = 196,
   EXTRACTOR_METATYPE_ALBUM_PEAK = 197,
   EXTRACTOR_METATYPE_REFERENCE_LEVEL = 198,
 
   EXTRACTOR_METATYPE_LOCATION_NAME = 199,
   EXTRACTOR_METATYPE_LOCATION_ELEVATION = 200,
   EXTRACTOR_METATYPE_LOCATION_HORIZONTAL_ERROR = 201,
   EXTRACTOR_METATYPE_LOCATION_MOVEMENT_SPEED = 202,
   EXTRACTOR_METATYPE_LOCATION_MOVEMENT_DIRECTION = 203,
   EXTRACTOR_METATYPE_LOCATION_CAPTURE_DIRECTION = 204,
 
   EXTRACTOR_METATYPE_SHOW_EPISODE_NUMBER = 205,
   EXTRACTOR_METATYPE_SHOW_SEASON_NUMBER = 206,
 
   EXTRACTOR_METATYPE_GROUPING = 207,
 
   EXTRACTOR_METATYPE_DEVICE_MANUFACTURER = 208,
   EXTRACTOR_METATYPE_DEVICE_MODEL = 209,
 
   EXTRACTOR_METATYPE_AUDIO_LANGUAGE = 210,
   EXTRACTOR_METATYPE_CHANNELS = 211,
   EXTRACTOR_METATYPE_SAMPLE_RATE = 212,
   EXTRACTOR_METATYPE_AUDIO_DEPTH = 213,
   EXTRACTOR_METATYPE_AUDIO_BITRATE = 214,
   EXTRACTOR_METATYPE_MAXIMUM_AUDIO_BITRATE = 215,
 
   EXTRACTOR_METATYPE_VIDEO_DIMENSIONS = 216,
   EXTRACTOR_METATYPE_VIDEO_DEPTH = 217,
   EXTRACTOR_METATYPE_FRAME_RATE = 218,
   EXTRACTOR_METATYPE_PIXEL_ASPECT_RATIO = 219,
   EXTRACTOR_METATYPE_VIDEO_BITRATE = 220,
   EXTRACTOR_METATYPE_MAXIMUM_VIDEO_BITRATE = 221,
 
   EXTRACTOR_METATYPE_SUBTITLE_LANGUAGE = 222,
   EXTRACTOR_METATYPE_VIDEO_LANGUAGE = 223,
 
   EXTRACTOR_METATYPE_TOC = 224,
 
   EXTRACTOR_METATYPE_VIDEO_DURATION = 225,
   EXTRACTOR_METATYPE_AUDIO_DURATION = 226,
   EXTRACTOR_METATYPE_SUBTITLE_DURATION = 227,
 
   EXTRACTOR_METATYPE_AUDIO_PREVIEW = 228,
 
   EXTRACTOR_METATYPE_NARINFO = 229,
   EXTRACTOR_METATYPE_NAR = 230,
 
   /**
    * Operating system the document was last written on, as recorded in
    * the PropertySetSystemIdentifier of an OLE2 property set.
    */
   EXTRACTOR_METATYPE_AUTHORING_OS = 231,
 
   /* The types below were introduced for formats whose interesting
      content is provenance rather than authorship: executables, disk
      images, databases, mail and geodata.  They are meant to survive a
      single fast pass over a file, so each of them is something that can
      be read out of a header without decoding the payload. */
 
   /**
    * Timestamp recorded by the linker or archiver when the file was
    * built, as opposed to when the file was created on this filesystem.
    */
   EXTRACTOR_METATYPE_BUILD_DATE = 232,
 
   /**
    * Identifier tying a binary to the debug information built with it
    * (PE debug directory GUID, Mach-O LC_UUID, ELF build-id).
    */
   EXTRACTOR_METATYPE_BUILD_ID = 233,
 
   /**
    * Compiler and linker that produced the file, where the format
    * records it separately from the authoring application (the PE
    * "Rich" header, for example).
    */
   EXTRACTOR_METATYPE_TOOLCHAIN = 234,
 
   /**
    * Path to the debug symbols recorded at build time.  Frequently
    * discloses the user name and directory layout of the build machine.
    */
   EXTRACTOR_METATYPE_DEBUG_PATH = 235,
 
   /**
    * Hash over the imported symbols of an executable ("imphash").
    */
   EXTRACTOR_METATYPE_IMPORT_HASH = 236,
 
   /**
    * Entry point of an executable or archive: a virtual address, or a
    * class name for a Java archive.
    */
   EXTRACTOR_METATYPE_ENTRY_POINT = 237,
 
   /**
    * Execution environment an executable asks the loader for, such as
    * "Windows GUI", "Windows console" or "native".
    */
   EXTRACTOR_METATYPE_SUBSYSTEM = 238,
 
   /**
    * Exploit mitigations the binary opts into (ASLR, DEP, control flow
    * guard, ...).
    */
   EXTRACTOR_METATYPE_SECURITY_MITIGATIONS = 239,
 
   /**
    * Entity that signed the file: a code signing subject, a certificate
    * common name, or the signing domain of a mail signature.
    */
   EXTRACTOR_METATYPE_SIGNER = 240,
 
   /**
    * Fingerprint of the certificate the file was signed with.
    */
   EXTRACTOR_METATYPE_CERTIFICATE_FINGERPRINT = 241,
 
   /**
    * Shannon entropy of the file or of one of its sections; high values
    * suggest compressed, encrypted or packed content.
    */
   EXTRACTOR_METATYPE_ENTROPY = 242,
 
   /**
    * Name of the product the file belongs to, where that is recorded
    * separately from the title.
    */
   EXTRACTOR_METATYPE_PRODUCT_NAME = 243,
 
   /**
    * Path this file points at: the target of a shortcut or a symlink.
    */
   EXTRACTOR_METATYPE_TARGET_PATH = 244,
 
   /**
    * Directory a shortcut or launcher starts its target in.
    */
   EXTRACTOR_METATYPE_WORKING_DIRECTORY = 245,
 
   /**
    * Arguments a shortcut or launcher passes to its target.
    */
   EXTRACTOR_METATYPE_COMMAND_LINE = 246,
 
   /**
    * Name of the user owning the file, as recorded inside the format.
    */
   EXTRACTOR_METATYPE_OWNER_USER = 247,
 
   /**
    * Name of the group owning the file, as recorded inside the format.
    */
   EXTRACTOR_METATYPE_OWNER_GROUP = 248,
 
   /**
    * Numeric user id of the owner, as recorded inside the format.
    */
   EXTRACTOR_METATYPE_OWNER_UID = 249,
 
   /**
    * Numeric group id of the owner, as recorded inside the format.
    */
   EXTRACTOR_METATYPE_OWNER_GID = 250,
 
   /**
    * Access permissions recorded inside the format, such as a Unix mode.
    */
   EXTRACTOR_METATYPE_PERMISSIONS = 251,
 
   /**
    * Time the file was last read, as recorded inside the format.
    */
   EXTRACTOR_METATYPE_ACCESS_DATE = 252,
 
   /**
    * Filesystem attribute flags recorded inside the format, such as
    * hidden, system, read-only or archive.
    */
   EXTRACTOR_METATYPE_ATTRIBUTES = 253,
 
   /**
    * Label of the volume the file describes or was taken from.
    */
   EXTRACTOR_METATYPE_VOLUME_NAME = 254,
 
   /**
    * Serial number or UUID identifying a volume or disk image.
    */
   EXTRACTOR_METATYPE_VOLUME_SERIAL = 255,
 
   /**
    * Capacity of the volume or virtual disk.
    */
   EXTRACTOR_METATYPE_VOLUME_SIZE = 256,
 
   /**
    * Size of the format's allocation unit: a sector, a database page or
    * a disk image cluster.
    */
   EXTRACTOR_METATYPE_BLOCK_SIZE = 257,
 
   /**
    * File system contained in or described by the file.
    */
   EXTRACTOR_METATYPE_FILESYSTEM_TYPE = 258,
 
   /**
    * Image this one is a delta against: a backing file or a
    * differencing parent.
    */
   EXTRACTOR_METATYPE_PARENT_IMAGE = 259,
 
   /**
    * Unused capacity reported by the format.
    */
   EXTRACTOR_METATYPE_FREE_SPACE = 260,
 
   /**
    * System the volume was intended for, as recorded in its descriptor.
    */
   EXTRACTOR_METATYPE_SYSTEM_IDENTIFIER = 261,
 
   /**
    * Party that assembled the data on a volume, as distinct from the
    * party that published it.
    */
   EXTRACTOR_METATYPE_DATA_PREPARER = 262,
 
   /**
    * Date after which the content is no longer considered valid.
    */
   EXTRACTOR_METATYPE_EXPIRATION_DATE = 263,
 
   /**
    * Encryption or digital restrictions protecting the content.
    */
   EXTRACTOR_METATYPE_ENCRYPTION = 264,
 
   /**
    * Identifier of the application that owns the file, such as a bundle
    * identifier or a database application id.
    */
   EXTRACTOR_METATYPE_APPLICATION_ID = 265,
 
   /**
    * Version of the schema the content is laid out according to.
    */
   EXTRACTOR_METATYPE_SCHEMA_VERSION = 266,
 
   /**
    * Counter the format increments on every modification.
    */
   EXTRACTOR_METATYPE_CHANGE_COUNTER = 267,
 
   /**
    * Crash recovery strategy a database is configured for.
    */
   EXTRACTOR_METATYPE_JOURNAL_MODE = 268,
 
   /**
    * Number of items the file holds: archive members, database records,
    * mail messages, placemarks.
    */
   EXTRACTOR_METATYPE_ENTRY_COUNT = 269,
 
   /**
    * Total size of the content once decompressed.
    */
   EXTRACTOR_METATYPE_UNCOMPRESSED_SIZE = 270,
 
   /**
    * Coordinate reference system geographic data is expressed in.
    */
   EXTRACTOR_METATYPE_COORDINATE_SYSTEM = 271,
 
   /**
    * Geographic extent covered by the file, as west, south, east, north.
    */
   EXTRACTOR_METATYPE_BOUNDING_BOX = 272,
 
   /**
    * Length of a recorded path.
    */
   EXTRACTOR_METATYPE_DISTANCE = 273,
 
   /**
    * Identifier assigned to a message by the system that created it.
    */
   EXTRACTOR_METATYPE_MESSAGE_ID = 274,
 
   /**
    * Identifier of the message this one answers.
    */
   EXTRACTOR_METATYPE_IN_REPLY_TO = 275,
 
   /**
    * Addressee of a message.
    */
   EXTRACTOR_METATYPE_RECIPIENT = 276,
 
   /**
    * One hop of the path a message travelled, as recorded by a relay.
    */
   EXTRACTOR_METATYPE_RECEIVED_FROM = 277,
 
   /**
    * Network address recorded in the file.
    */
   EXTRACTOR_METATYPE_IP_ADDRESS = 278,
 
   /**
    * Parameters the encoder was invoked with.
    */
   EXTRACTOR_METATYPE_ENCODER_SETTINGS = 279,
 
   /**
    * Whether the bitrate is constant, variable or average.
    */
   EXTRACTOR_METATYPE_BITRATE_MODE = 280,
 
   /**
    * Bits per colour component.
    */
   EXTRACTOR_METATYPE_COLOR_DEPTH = 281,
 
   /**
    * Colour space or ICC profile the content is expressed in.
    */
   EXTRACTOR_METATYPE_COLOR_PROFILE = 282,
 
   /**
    * Specifications a container declares itself compatible with.
    */
   EXTRACTOR_METATYPE_COMPATIBLE_BRANDS = 283,
 
   /**
    * Account the content was bought with, as embedded by the store.
    */
   EXTRACTOR_METATYPE_PURCHASE_ACCOUNT = 284,
 
   /**
    * Marking identifying the recipient of an individual copy.
    */
   EXTRACTOR_METATYPE_WATERMARK = 285,
 
   /**
    * International standard book number.
    */
   EXTRACTOR_METATYPE_ISBN = 286,
 
   /**
    * Capability an application asks the platform for.
    */
   EXTRACTOR_METATYPE_PERMISSION = 287,
 
   /**
    * Hardware address recorded in the file.
    */
   EXTRACTOR_METATYPE_MAC_ADDRESS = 288,
 
   /**
    * Name of the machine the file originated on.
    */
   EXTRACTOR_METATYPE_SOURCE_HOST = 289,
 
   /**
    * Oldest platform release the content will run on.
    */
   EXTRACTOR_METATYPE_MINIMUM_OS_VERSION = 290,
 
   /**
    * Full text of the document as UTF-8, paragraphs separated by
    * "\n\n".  Only produced on request (plugin option "fulltext").
    */
   EXTRACTOR_METATYPE_FULL_TEXT = 291,
 
   /**
    * Complete subtitle track as a UTF-8 SRT file.  Only produced on
    * request (plugin option "srt:LANG").
    */
   EXTRACTOR_METATYPE_SUBTITLE_TEXT = 292,
 
   EXTRACTOR_METATYPE_LAST = 293
 };
 
 /** @} */ /* end of meta data types */
 
 /**
  * Get the textual name of the keyword.
  *
  * @param type meta type to get a UTF-8 string for
  * @return NULL if the type is not known, otherwise
  *         an English (locale: C) string describing the type;
  *         translate using `dgettext ("libextractor", rval)`
  * @ingroup types
  */
 _EXTRACTOR_EXTERN const char *
 EXTRACTOR_metatype_to_string (enum EXTRACTOR_MetaType type);
 
 
 /**
  * Get a long description for the meta type.
  *
  * @param type meta type to get a UTF-8 description for
  * @return NULL if the type is not known, otherwise
  *         an English (locale: C) string describing the type;
  *         translate using `dgettext ("libextractor", rval)`
  * @ingroup types
  */
 _EXTRACTOR_EXTERN const char *
 EXTRACTOR_metatype_to_description (enum EXTRACTOR_MetaType type);
 
 
 /**
  * Return the highest type number, exclusive as in [0,max).
  *
  * @return highest legal metatype number for this version of libextractor
  * @ingroup types
  */
 _EXTRACTOR_EXTERN enum EXTRACTOR_MetaType
 EXTRACTOR_metatype_get_max (void);
 
 
 /**
  * Type of a function that libextractor calls for each
  * meta data item found.
  *
  * @param cls closure (user-defined)
  * @param plugin_name name of the plugin that produced this value;
  *        special values can be used (i.e. '&lt;zlib&gt;' for zlib being
  *        used in the main libextractor library and yielding
  *        meta data).
  * @param type libextractor-type describing the meta data
  * @param format basic format information about @a data
  * @param data_mime_type mime-type of @a data (not of the original file);
  *        can be NULL (if mime-type is not known)
  * @param data actual meta-data found
  * @param data_len number of bytes in @a data
  * @return 0 to continue extracting, 1 to abort
  */
 typedef int
 (*EXTRACTOR_MetaDataProcessor) (void *cls,
                                 const char *plugin_name,
                                 enum EXTRACTOR_MetaType type,
                                 enum EXTRACTOR_MetaFormat format,
                                 const char *data_mime_type,
                                 const char *data,
                                 size_t data_len);
 
 
 /**
  * Context provided for plugins that perform meta data extraction.
  */
 struct EXTRACTOR_ExtractContext
 {
 
   /**
    * Closure argument to pass to all callbacks.
    */
   void *cls;
 
   /**
    * Configuration string for the plugin.
    */
   const char *config;
 
   /**
    * Obtain a pointer to up to @a size bytes of data from the file to process.
    *
    * @param cls the @e cls member of this struct
    * @param data pointer to set to the file data, set to NULL on error
    * @param size maximum number of bytes requested
    * @return number of bytes now available in @a data (can be smaller than @a size),
    *         -1 on error
    */
   ssize_t (*read) (void *cls,
                    void **data,
                    size_t size);
 
 
   /**
    * Seek in the file.  Use `SEEK_CUR` for @a whence and @a pos of 0 to
    * obtain the current position in the file.
    *
    * Out of process, a plugin that neither reads, seeks nor reports meta
    * data for 500 ms is presumed hung and killed.  A plugin that
    * legitimately computes for longer without touching the file (full
    * text of a large document, a video gallery, ...) must call
    * `seek (cls, 0, SEEK_CUR)` regularly (at least every 250 ms) to show
    * it is still making progress; the call is cheap and rate-limited.
    *
    * @param cls the @e cls member of this struct
    * @param pos position to seek (see 'man lseek')
    * @param whence how to see (absolute to start, relative, absolute to end)
    * @return new absolute position, -1 on error (i.e. desired position
    *         does not exist)
    */
   int64_t (*seek) (void *cls,
                    int64_t pos,
                    int whence);
 
 
   /**
    * Determine the overall size of the file.
    *
    * @param cls the @a cls member of this struct
    * @return overall file size, `UINT64_MAX` on error (i.e. IPC failure)
    */
   uint64_t (*get_size) (void *cls);
 
   /**
    * Function to call on extracted data.
    */
   EXTRACTOR_MetaDataProcessor proc;
 
 };
 
 
 /**
  * Signature of the extract method that each plugin
  * must provide.
  *
  * @param ec extraction context provided to the plugin
  */
 typedef void
 (*EXTRACTOR_extract_method) (struct EXTRACTOR_ExtractContext *ec);
 
 
 /**
  * Linked list of extractor plugins.  An application builds this list
  * by telling libextractor to load various keyword-extraction
  * plugins. Libraries can also be unloaded (removed from this list,
  * see #EXTRACTOR_plugin_remove).
  */
 struct EXTRACTOR_PluginList;
 
 
 /**
  * Load the default set of plugins.  The default can be changed
  * by setting the LIBEXTRACTOR_LIBRARIES environment variable;
  * If it is set to "env", then this function will return
  * #EXTRACTOR_plugin_add_config (NULL, env, flags).
  *
  * If LIBEXTRACTOR_LIBRARIES is not set, the function will attempt
  * to locate the installed plugins and load all of them.
  * The directory where the code will search for plugins is typically
  * automatically determined; it can be specified explicitly using the
  * "LIBEXTRACTOR_PREFIX" environment variable.
  *
  * This environment variable must be set to the precise directory with
  * the plugins (i.e. "/usr/lib/libextractor", not "/usr").  Note that
  * setting the environment variable will disable all of the methods
  * that are typically used to determine the location of plugins.
  * Multiple paths can be specified using ':' to separate them.
  *
  * @param flags options for all of the plugins loaded
  * @return the default set of plugins, NULL if no plugins were found
  */
 _EXTRACTOR_EXTERN struct EXTRACTOR_PluginList *
 EXTRACTOR_plugin_add_defaults (enum EXTRACTOR_Options flags);
 
 
 /**
  * Add a library for keyword extraction.
  *
  * @param prev the previous list of libraries, may be NULL
  * @param library the name of the library (short handle, i.e. "mime")
  * @param options options to give to the library
  * @param flags options to use
  * @return the new list of libraries, equal to prev iff an error occured
  */
 _EXTRACTOR_EXTERN struct EXTRACTOR_PluginList *
 EXTRACTOR_plugin_add (struct EXTRACTOR_PluginList *prev,
                       const char *library,
                       const char *options,
                       enum EXTRACTOR_Options flags);
 
 
 /**
  * Load multiple libraries as specified by the user.
  *
  * @param config a string given by the user that defines which
  *        libraries should be loaded. Has the format
  *        "[[-]LIBRARYNAME[(options)][:[-]LIBRARYNAME[(options)]]]*".
  *        For example, 'mp3:ogg' loads the
  *        mp3 and the ogg plugins. The '-' before the LIBRARYNAME
  *        indicates that the library should be removed from
  *        the library list.
  * @param prev the  previous list of libraries, may be NULL
  * @param flags options to use
  * @return the new list of libraries, equal to prev iff an error occured
  *         or if config was empty (or NULL).
  */
 _EXTRACTOR_EXTERN struct EXTRACTOR_PluginList *
 EXTRACTOR_plugin_add_config (struct EXTRACTOR_PluginList *prev,
                              const char *config,
                              enum EXTRACTOR_Options flags);
 
 
 /**
  * Remove a plugin from a list.
  *
  * @param prev the current list of plugins
  * @param library the name of the plugin to remove (short handle)
  * @return the reduced list, unchanged if the plugin was not loaded
  */
 _EXTRACTOR_EXTERN struct EXTRACTOR_PluginList *
 EXTRACTOR_plugin_remove (struct EXTRACTOR_PluginList *prev,
                          const char *library);
 
 
 /**
  * Remove all plugins from the given list (destroys the list).
  *
  * @param plugin the list of plugins
  */
 _EXTRACTOR_EXTERN void
 EXTRACTOR_plugin_remove_all (struct EXTRACTOR_PluginList *plugins);
 
 
 /**
  * Extract keywords from a file using the given set of plugins.
  *
  * @param plugins the list of plugins to use
  * @param filename the name of the file, can be NULL if @a data is not NULL
  * @param data data of the file in memory, can be NULL (in which
  *        case libextractor will open file) if filename is not NULL
  * @param size number of bytes in @a data, ignored if @a data is NULL
  * @param proc function to call for each meta data item found
  * @param proc_cls cls argument to @a proc
  */
 _EXTRACTOR_EXTERN void
 EXTRACTOR_extract (struct EXTRACTOR_PluginList *plugins,
                    const char *filename,
                    const void *data,
                    size_t size,
                    EXTRACTOR_MetaDataProcessor proc,
                    void *proc_cls);
 
 
 /**
  * Simple #EXTRACTOR_MetaDataProcessor implementation that simply
  * prints the extracted meta data to the given file.  Only prints
  * those keywords that are in UTF-8 format.
  *
  * @param handle the file to write to (`stdout`, `stderr`), must NOT be NULL,
  *               must be of type `FILE *`.
  * @param plugin_name name of the plugin that produced this value
  * @param type libextractor-type describing the meta data
  * @param format basic format information about data
  * @param data_mime_type mime-type of @a data (not of the original file);
  *        can be NULL (if mime-type is not known)
  * @param data actual meta-data found
  * @param data_len number of bytes in @a data
  * @return non-zero if printing failed, otherwise 0.
  */
 _EXTRACTOR_EXTERN int
 EXTRACTOR_meta_data_print (void *handle,
                            const char *plugin_name,
                            enum EXTRACTOR_MetaType type,
                            enum EXTRACTOR_MetaFormat format,
                            const char *data_mime_type,
                            const char *data,
                            size_t data_len);
 
 
 #if 0 /* keep Emacsens' auto-indent happy */
 {
 #endif
 #ifdef __cplusplus
 }
 #endif
 
 #endif