xref: /third_party/libsnd/include/sndfile.h

/*
 * Copyright (C) 1999-2016 Erik de Castro Lopo <erikd@mega-nerd.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation; either version 2.1 of the License, or
 * (at your option) any later version.
 *
 * This program 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 Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/

/*
 * sndfile.h -- system-wide definitions
 *
 * API documentation is in the doc/ directory of the source code tarball
 * and at http://libsndfile.github.io/libsndfile/api.html.
*/

#ifndef SNDFILE_H
#define SNDFILE_H

/* This is the version 1.0.X header file. */
#define SNDFILE_1

#include <stdio.h>
#include <stdint.h>
#include <sys/types.h>

#ifdef __cplusplus
extern "C" {
#endif /* __cplusplus */

/* The following file types can be read and written.
 * A file type would consist of a major type (ie SF_FORMAT_WAV) bitwise
 * ORed with a minor type (ie SF_FORMAT_PCM). SF_FORMAT_TYPEMASK and
 * SF_FORMAT_SUBMASK can be used to separate the major and minor file
 * types.
*/

enum {
    /* Major formats. */
    SF_FORMAT_WAV = 0x010000, /* Microsoft WAV format (little endian default). */
    SF_FORMAT_AIFF = 0x020000, /* Apple/SGI AIFF format (big endian). */
    SF_FORMAT_AU = 0x030000, /* Sun/NeXT AU format (big endian). */
    SF_FORMAT_RAW = 0x040000, /* RAW PCM data. */
    SF_FORMAT_PAF = 0x050000, /* Ensoniq PARIS file format. */
    SF_FORMAT_SVX = 0x060000, /* Amiga IFF / SVX8 / SV16 format. */
    SF_FORMAT_NIST = 0x070000, /* Sphere NIST format. */
    SF_FORMAT_VOC = 0x080000, /* VOC files. */
    SF_FORMAT_IRCAM = 0x0A0000, /* Berkeley/IRCAM/CARL */
    SF_FORMAT_W64 = 0x0B0000, /* Sonic Foundry's 64 bit RIFF/WAV */
    SF_FORMAT_MAT4 = 0x0C0000, /* Matlab (tm) V4.2 / GNU Octave 2.0 */
    SF_FORMAT_MAT5 = 0x0D0000, /* Matlab (tm) V5.0 / GNU Octave 2.1 */
    SF_FORMAT_PVF = 0x0E0000, /* Portable Voice Format */
    SF_FORMAT_XI = 0x0F0000, /* Fasttracker 2 Extended Instrument */
    SF_FORMAT_HTK = 0x100000, /* HMM Tool Kit format */
    SF_FORMAT_SDS = 0x110000, /* Midi Sample Dump Standard */
    SF_FORMAT_AVR = 0x120000, /* Audio Visual Research */
    SF_FORMAT_WAVEX = 0x130000, /* MS WAVE with WAVEFORMATEX */
    SF_FORMAT_SD2 = 0x160000, /* Sound Designer 2 */
    SF_FORMAT_FLAC = 0x170000, /* FLAC lossless file format */
    SF_FORMAT_CAF = 0x180000, /* Core Audio File format */
    SF_FORMAT_WVE = 0x190000, /* Psion WVE format */
    SF_FORMAT_OGG = 0x200000, /* Xiph OGG container */
    SF_FORMAT_MPC2K = 0x210000, /* Akai MPC 2000 sampler */
    SF_FORMAT_RF64 = 0x220000, /* RF64 WAV file */
    SF_FORMAT_MPEG = 0x230000, /* MPEG-1/2 audio stream */
    /* Subtypes from here on. */
    SF_FORMAT_PCM_S8 = 0x0001, /* Signed 8 bit data */
    SF_FORMAT_PCM_16 = 0x0002, /* Signed 16 bit data */
    SF_FORMAT_PCM_24 = 0x0003, /* Signed 24 bit data */
    SF_FORMAT_PCM_32 = 0x0004, /* Signed 32 bit data */
    SF_FORMAT_PCM_U8 = 0x0005, /* Unsigned 8 bit data (WAV and RAW only) */
    SF_FORMAT_FLOAT = 0x0006, /* 32 bit float data */
    SF_FORMAT_DOUBLE = 0x0007, /* 64 bit float data */
    SF_FORMAT_ULAW = 0x0010, /* U-Law encoded. */
    SF_FORMAT_ALAW = 0x0011, /* A-Law encoded. */
    SF_FORMAT_IMA_ADPCM = 0x0012, /* IMA ADPCM. */
    SF_FORMAT_MS_ADPCM = 0x0013, /* Microsoft ADPCM. */
    SF_FORMAT_GSM610 = 0x0020, /* GSM 6.10 encoding. */
    SF_FORMAT_VOX_ADPCM = 0x0021, /* OKI / Dialogix ADPCM */
    SF_FORMAT_NMS_ADPCM_16 = 0x0022, /* 16kbs NMS G721-variant encoding. */
    SF_FORMAT_NMS_ADPCM_24 = 0x0023, /* 24kbs NMS G721-variant encoding. */
    SF_FORMAT_NMS_ADPCM_32 = 0x0024, /* 32kbs NMS G721-variant encoding. */
    SF_FORMAT_G721_32 = 0x0030, /* 32kbs G721 ADPCM encoding. */
    SF_FORMAT_G723_24 = 0x0031, /* 24kbs G723 ADPCM encoding. */
    SF_FORMAT_G723_40 = 0x0032, /* 40kbs G723 ADPCM encoding. */
    SF_FORMAT_DWVW_12 = 0x0040,  /* 12 bit Delta Width Variable Word encoding. */
    SF_FORMAT_DWVW_16 = 0x0041,  /* 16 bit Delta Width Variable Word encoding. */
    SF_FORMAT_DWVW_24 = 0x0042,  /* 24 bit Delta Width Variable Word encoding. */
    SF_FORMAT_DWVW_N = 0x0043,  /* N bit Delta Width Variable Word encoding. */
    SF_FORMAT_DPCM_8 = 0x0050, /* 8 bit differential PCM (XI only) */
    SF_FORMAT_DPCM_16 = 0x0051, /* 16 bit differential PCM (XI only) */
    SF_FORMAT_VORBIS = 0x0060, /* Xiph Vorbis encoding. */
    SF_FORMAT_OPUS = 0x0064, /* Xiph/Skype Opus encoding. */
    SF_FORMAT_ALAC_16 = 0x0070, /* Apple Lossless Audio Codec (16 bit). */
    SF_FORMAT_ALAC_20 = 0x0071, /* Apple Lossless Audio Codec (20 bit). */
    SF_FORMAT_ALAC_24 = 0x0072, /* Apple Lossless Audio Codec (24 bit). */
    SF_FORMAT_ALAC_32 = 0x0073, /* Apple Lossless Audio Codec (32 bit). */
    SF_FORMAT_MPEG_LAYER_I = 0x0080, /* MPEG-1 Audio Layer I */
    SF_FORMAT_MPEG_LAYER_II = 0x0081, /* MPEG-1 Audio Layer II */
    SF_FORMAT_MPEG_LAYER_III = 0x0082, /* MPEG-2 Audio Layer III */
    /* Endian-ness options. */
    SF_ENDIAN_FILE = 0x00000000, /* Default file endian-ness. */
    SF_ENDIAN_LITTLE = 0x10000000, /* Force little endian-ness. */
    SF_ENDIAN_BIG = 0x20000000, /* Force big endian-ness. */
    SF_ENDIAN_CPU = 0x30000000, /* Force CPU endian-ness. */
    SF_FORMAT_SUBMASK = 0x0000FFFF,
    SF_FORMAT_TYPEMASK = 0x0FFF0000,
    SF_FORMAT_ENDMASK = 0x30000000
};

/*
 * The following are the valid command numbers for the sf_command()
 * interface.  The use of these commands is documented in the file
 * command.html in the doc directory of the source code distribution.
*/
enum {
    SFC_GET_LIB_VERSION = 0x1000,
    SFC_GET_LOG_INFO = 0x1001,
    SFC_GET_CURRENT_SF_INFO = 0x1002,
    SFC_GET_NORM_DOUBLE = 0x1010,
    SFC_GET_NORM_FLOAT = 0x1011,
    SFC_SET_NORM_DOUBLE = 0x1012,
    SFC_SET_NORM_FLOAT = 0x1013,
    SFC_SET_SCALE_FLOAT_INT_READ = 0x1014,
    SFC_SET_SCALE_INT_FLOAT_WRITE = 0x1015,
    SFC_GET_SIMPLE_FORMAT_COUNT = 0x1020,
    SFC_GET_SIMPLE_FORMAT = 0x1021,
    SFC_GET_FORMAT_INFO = 0x1028,
    SFC_GET_FORMAT_MAJOR_COUNT = 0x1030,
    SFC_GET_FORMAT_MAJOR = 0x1031,
    SFC_GET_FORMAT_SUBTYPE_COUNT = 0x1032,
    SFC_GET_FORMAT_SUBTYPE = 0x1033,
    SFC_CALC_SIGNAL_MAX = 0x1040,
    SFC_CALC_NORM_SIGNAL_MAX = 0x1041,
    SFC_CALC_MAX_ALL_CHANNELS = 0x1042,
    SFC_CALC_NORM_MAX_ALL_CHANNELS = 0x1043,
    SFC_GET_SIGNAL_MAX = 0x1044,
    SFC_GET_MAX_ALL_CHANNELS = 0x1045,
    SFC_SET_ADD_PEAK_CHUNK = 0x1050,
    SFC_UPDATE_HEADER_NOW = 0x1060,
    SFC_SET_UPDATE_HEADER_AUTO = 0x1061,
    SFC_FILE_TRUNCATE = 0x1080,
    SFC_SET_RAW_START_OFFSET = 0x1090,
 /* Commands reserved for dithering, which is not implemented. */
    SFC_SET_DITHER_ON_WRITE = 0x10A0,
    SFC_SET_DITHER_ON_READ = 0x10A1,
    SFC_GET_DITHER_INFO_COUNT = 0x10A2,
    SFC_GET_DITHER_INFO = 0x10A3,
    SFC_GET_EMBED_FILE_INFO = 0x10B0,
    SFC_SET_CLIPPING = 0x10C0,
    SFC_GET_CLIPPING = 0x10C1,
    SFC_GET_CUE_COUNT = 0x10CD,
    SFC_GET_CUE = 0x10CE,
    SFC_SET_CUE = 0x10CF,
    SFC_GET_INSTRUMENT = 0x10D0,
    SFC_SET_INSTRUMENT = 0x10D1,
    SFC_GET_LOOP_INFO = 0x10E0,
    SFC_GET_BROADCAST_INFO = 0x10F0,
    SFC_SET_BROADCAST_INFO = 0x10F1,
    SFC_GET_CHANNEL_MAP_INFO = 0x1100,
    SFC_SET_CHANNEL_MAP_INFO = 0x1101,
    SFC_RAW_DATA_NEEDS_ENDSWAP = 0x1110,
    /* Support for Wavex Ambisonics Format */
    SFC_WAVEX_SET_AMBISONIC = 0x1200,
    SFC_WAVEX_GET_AMBISONIC = 0x1201,
    /*
    * RF64 files can be set so that on-close, writable files that have less
    * than 4GB of data in them are converted to RIFF/WAV, as per EBU
    * recommendations.
    */
    SFC_RF64_AUTO_DOWNGRADE = 0x1210,
    SFC_SET_VBR_ENCODING_QUALITY = 0x1300,
    SFC_SET_COMPRESSION_LEVEL = 0x1301,
    SFC_SET_OGG_PAGE_LATENCY_MS = 0x1302,
    SFC_SET_OGG_PAGE_LATENCY = 0x1303,
    SFC_GET_BITRATE_MODE = 0x1302,
    SFC_SET_BITRATE_MODE = 0x1303,
    /* Cart Chunk support */
    SFC_SET_CART_INFO = 0x1400,
    SFC_GET_CART_INFO = 0x1401,
    /* Opus files original samplerate metadata */
    SFC_SET_ORIGINAL_SAMPLERATE = 0x1500,
    SFC_GET_ORIGINAL_SAMPLERATE = 0x1501,
    /* Following commands for testing only. */
    SFC_TEST_IEEE_FLOAT_REPLACE = 0x6001,
    /*
    * These SFC_SET_ADD_* values are deprecated and will disappear at some
    * time in the future. They are guaranteed to be here up to and
    * including version 1.0.8 to avoid breakage of existing software.
    * They currently do nothing and will continue to do nothing.
    */
    SFC_SET_ADD_HEADER_PAD_CHUNK = 0x1051,
    SFC_SET_ADD_DITHER_ON_WRITE = 0x1070,
    SFC_SET_ADD_DITHER_ON_READ = 0x1071
};

    /*
    * String types that can be set and read from files. Not all file types
    * support this and even the file types which support one, may not support
    * all string types.
    */
enum {
    SF_STR_TITLE = 0x01,
    SF_STR_COPYRIGHT = 0x02,
    SF_STR_SOFTWARE = 0x03,
    SF_STR_ARTIST = 0x04,
    SF_STR_COMMENT = 0x05,
    SF_STR_DATE = 0x06,
    SF_STR_ALBUM = 0x07,
    SF_STR_LICENSE = 0x08,
    SF_STR_TRACKNUMBER = 0x09,
    SF_STR_GENRE = 0x10
};

/*
 * Use the following as the start and end index when doing metadata
 * transcoding.
*/

#define SF_STR_FIRST SF_STR_TITLE
#define SF_STR_LAST SF_STR_GENRE

enum {
    /* True and false */
    SF_FALSE = 0,
    SF_TRUE = 1,
    /* Modes for opening files. */
    SFM_READ = 0x10,
    SFM_WRITE = 0x20,
    SFM_RDWR = 0x30,

    SF_AMBISONIC_NONE = 0x40,
    SF_AMBISONIC_B_FORMAT = 0x41
};

/* Public error values. These are guaranteed to remain unchanged for the duration
 * of the library major version number.
 * There are also a large number of private error numbers which are internal to
 * the library which can change at any time.
*/

enum {
    SF_ERR_NO_ERROR = 0,
    SF_ERR_UNRECOGNISED_FORMAT = 1,
    SF_ERR_SYSTEM = 2,
    SF_ERR_MALFORMED_FILE = 3,
    SF_ERR_UNSUPPORTED_ENCODING = 4
};


/* Channel map values (used with SFC_SET/GET_CHANNEL_MAP).
*/

enum {
    SF_CHANNEL_MAP_INVALID = 0,
    SF_CHANNEL_MAP_MONO = 1,
    SF_CHANNEL_MAP_LEFT, /* Apple calls this 'Left' */
    SF_CHANNEL_MAP_RIGHT, /* Apple calls this 'Right' */
    SF_CHANNEL_MAP_CENTER, /* Apple calls this 'Center' */
    SF_CHANNEL_MAP_FRONT_LEFT,
    SF_CHANNEL_MAP_FRONT_RIGHT,
    SF_CHANNEL_MAP_FRONT_CENTER,
    SF_CHANNEL_MAP_REAR_CENTER, /* Apple calls this 'Center Surround', Msft calls this 'Back Center' */
    SF_CHANNEL_MAP_REAR_LEFT, /* Apple calls this 'Left Surround', Msft calls this 'Back Left' */
    SF_CHANNEL_MAP_REAR_RIGHT, /* Apple calls this 'Right Surround', Msft calls this 'Back Right' */
    SF_CHANNEL_MAP_LFE, /* Apple calls this 'LFEScreen', Msft calls this 'Low Frequency'  */
    SF_CHANNEL_MAP_FRONT_LEFT_OF_CENTER, /* Apple calls this 'Left Center' */
    SF_CHANNEL_MAP_FRONT_RIGHT_OF_CENTER, /* Apple calls this 'Right Center */
    SF_CHANNEL_MAP_SIDE_LEFT, /* Apple calls this 'Left Surround Direct' */
    SF_CHANNEL_MAP_SIDE_RIGHT, /* Apple calls this 'Right Surround Direct' */
    SF_CHANNEL_MAP_TOP_CENTER, /* Apple calls this 'Top Center Surround' */
    SF_CHANNEL_MAP_TOP_FRONT_LEFT, /* Apple calls this 'Vertical Height Left' */
    SF_CHANNEL_MAP_TOP_FRONT_RIGHT, /* Apple calls this 'Vertical Height Right' */
    SF_CHANNEL_MAP_TOP_FRONT_CENTER, /* Apple calls this 'Vertical Height Center' */
    SF_CHANNEL_MAP_TOP_REAR_LEFT, /* Apple and MS call this 'Top Back Left' */
    SF_CHANNEL_MAP_TOP_REAR_RIGHT, /* Apple and MS call this 'Top Back Right' */
    SF_CHANNEL_MAP_TOP_REAR_CENTER, /* Apple and MS call this 'Top Back Center' */
    SF_CHANNEL_MAP_AMBISONIC_B_W,
    SF_CHANNEL_MAP_AMBISONIC_B_X,
    SF_CHANNEL_MAP_AMBISONIC_B_Y,
    SF_CHANNEL_MAP_AMBISONIC_B_Z,
    SF_CHANNEL_MAP_MAX
};

/* Bitrate mode values (for use with SFC_GET/SET_BITRATE_MODE)
*/
enum {
    SF_BITRATE_MODE_CONSTANT = 0,
    SF_BITRATE_MODE_AVERAGE,
    SF_BITRATE_MODE_VARIABLE
};


/* A SNDFILE* pointer can be passed around much like stdio.h's FILE* pointer. */

typedef struct sf_private_tag SNDFILE;

/* The following typedef is system specific and is defined when libsndfile is
 * compiled. sf_count_t will be a 64 bit value when the underlying OS allows
 * 64 bit file offsets.
 * On windows, we need to allow the same header file to be compiler by both GCC
 * and the Microsoft compiler.
*/

typedef int64_t sf_count_t;
#ifndef SF_COUNT_MAX
#define SF_COUNT_MAX 0x7FFFFFFFFFFFFFFFLL
#endif


/* A pointer to a SF_INFO structure is passed to sf_open () and filled in.
 * On write, the SF_INFO structure is filled in by the user and passed into
 * sf_open ().
*/

struct SF_INFO {
    sf_count_t frames; /* Used to be called samples.  Changed to avoid confusion. */
    int samplerate;
    int channels;
    int format;
    int sections;
    int seekable;
};

typedef struct SF_INFO SF_INFO;

/* The SF_FORMAT_INFO struct is used to retrieve information about the sound
 * file formats libsndfile supports using the sf_command () interface.
 *
 * Using this interface will allow applications to support new file formats
 * and encoding types when libsndfile is upgraded, without requiring
 * re-compilation of the application.
 *
 * Please consult the libsndfile documentation (particularly the information
 * on the sf_command () interface) for examples of its use.
*/

typedef struct {
    int format;
    const char *name;
    const char *extension;
} SF_FORMAT_INFO;

/*
 * Enums and typedefs for adding dither on read and write.
 * Reserved for future implementation.
*/

enum {
    SFD_DEFAULT_LEVEL = 0,
    SFD_CUSTOM_LEVEL = 0x40000000,
    SFD_NO_DITHER = 500,
    SFD_WHITE = 501,
    SFD_TRIANGULAR_PDF = 502
};

typedef struct {
    int type;
    double level;
    const char *name;
} SF_DITHER_INFO;

 /* Struct used to retrieve information about a file embedded within a
 * larger file. See SFC_GET_EMBED_FILE_INFO.
 */

typedef struct {
    sf_count_t offset;
    sf_count_t length;
} SF_EMBED_FILE_INFO;

/*
 * Struct used to retrieve cue marker information from a file
*/

typedef struct {
    int32_t indx;
    uint32_t position;
    int32_t fcc_chunk;
    int32_t chunk_start;
    int32_t block_start;
    uint32_t sample_offset;
    char name [256];
} SF_CUE_POINT;

#define SF_CUES_VAR(count) \
    struct \
    { \
    uint32_t cue_count; \
    SF_CUE_POINT cue_points [count]; \
    }

typedef SF_CUES_VAR (100) SF_CUES;

/*
 * Structs used to retrieve music sample information from a file.
*/

enum {
 /*
 * The loop mode field in SF_INSTRUMENT will be one of the following.
 */
    SF_LOOP_NONE = 800,
    SF_LOOP_FORWARD,
    SF_LOOP_BACKWARD,
    SF_LOOP_ALTERNATING
};

typedef struct {
    int gain;
    char basenote, detune;
    char velocity_lo, velocity_hi;
    char key_lo, key_hi;
    int loop_count;

    struct {
    int mode;
    uint32_t start;
    uint32_t end;
    uint32_t count;
    } loops [16]; /* make variable in a sensible way */
} SF_INSTRUMENT;

/* Struct used to retrieve loop information from a file. */
typedef struct {
    short time_sig_num; /* any positive integer    > 0  */
    short time_sig_den; /* any positive power of 2 > 0  */
    int loop_mode; /* see SF_LOOP enum */

    int num_beats; /* this is NOT the amount of quarter notes !!! */
   /* a full bar of 4/4 is 4 beats */
   /* a full bar of 7/8 is 7 beats */

    float bpm; /* suggestion, as it can be calculated using other fields: */
   /* file's length, file's sampleRate and our time_sig_den */
   /* -> bpms are always the amount of _quarter notes_ per minute */

    int root_key; /* MIDI note, or -1 for None */
    int future [6];
} SF_LOOP_INFO;


/* Struct used to retrieve broadcast (EBU) information from a file.
 * Strongly (!) based on EBU "bext" chunk format used in Broadcast WAVE.
*/
#define SF_BROADCAST_INFO_VAR(coding_hist_size) \
    struct \
    { \
    char description [256]; \
    char originator [32]; \
    char originator_reference [32]; \
    char origination_date [10]; \
    char origination_time [8]; \
    uint32_t time_reference_low; \
    uint32_t time_reference_high; \
    short version; \
    char umid [64]; \
    int16_t loudness_value; \
    int16_t loudness_range; \
    int16_t max_true_peak_level; \
    int16_t max_momentary_loudness; \
    int16_t max_shortterm_loudness; \
    char reserved [180]; \
    uint32_t    coding_history_size; \
    char coding_history [coding_hist_size]; \
    }

/* SF_BROADCAST_INFO is the above struct with coding_history field of 256 bytes. */
typedef SF_BROADCAST_INFO_VAR (256) SF_BROADCAST_INFO;

struct SF_CART_TIMER {
    char usage [4];
    int32_t value;
};

typedef struct SF_CART_TIMER SF_CART_TIMER;

#define SF_CART_INFO_VAR(p_tag_text_size) \
    struct \
    { \
    char version [4]; \
    char title [64]; \
    char artist [64]; \
    char cut_id [64]; \
    char client_id [64]; \
    char category [64]; \
    char classification [64]; \
    char out_cue [64]; \
    char start_date [10]; \
    char start_time [8]; \
    char end_date [10]; \
    char end_time [8]; \
    char producer_app_id [64]; \
    char producer_app_version [64]; \
    char user_def [64]; \
    int32_t level_reference; \
    SF_CART_TIMER    post_timers [8]; \
    char reserved [276]; \
    char url [1024]; \
    uint32_t    tag_text_size; \
    char tag_text [p_tag_text_size]; \
    }

typedef SF_CART_INFO_VAR (256) SF_CART_INFO;

/*    Virtual I/O functionality. */

typedef sf_count_t (*sf_vio_get_filelen)    (void *user_data);
typedef sf_count_t (*sf_vio_seek) (sf_count_t offset, int whence, void *user_data);
typedef sf_count_t (*sf_vio_read) (void *ptr, sf_count_t count, void *user_data);
typedef sf_count_t (*sf_vio_write) (const void *ptr, sf_count_t count, void *user_data);
typedef sf_count_t (*sf_vio_tell) (void *user_data);

struct SF_VIRTUAL_IO {
    sf_vio_get_filelen get_filelen;
    sf_vio_seek seek;
    sf_vio_read read;
    sf_vio_write write;
    sf_vio_tell tell;
};

typedef struct SF_VIRTUAL_IO SF_VIRTUAL_IO;


/* Open the specified file for read, write or both. On error, this will
 * return a NULL pointer. To find the error number, pass a NULL SNDFILE
 * to sf_strerror ().
 * All calls to sf_open() should be matched with a call to sf_close().
*/

SNDFILE* sf_open (const char *path, int mode, SF_INFO *sfinfo);


/* Use the existing file descriptor to create a SNDFILE object. If close_desc
 * is TRUE, the file descriptor will be closed when sf_close() is called. If
 * it is FALSE, the descriptor will not be closed.
 * When passed a descriptor like this, the library will assume that the start
 * of file header is at the current file offset. This allows sound files within
 * larger container files to be read and/or written.
 * On error, this will return a NULL pointer. To find the error number, pass a
 * NULL SNDFILE to sf_strerror ().
 * All calls to sf_open_fd() should be matched with a call to sf_close().

*/

SNDFILE* sf_open_fd (int fd, int mode, SF_INFO *sfinfo, int close_desc);

SNDFILE* sf_open_virtual (SF_VIRTUAL_IO *sfvirtual, int mode, SF_INFO *sfinfo, void *user_data);


/* sf_error () returns a error number which can be translated to a text
 * string using sf_error_number().
*/

int sf_error (SNDFILE *sndfile);


/* sf_strerror () returns to the caller a pointer to the current error message for
 * the given SNDFILE.
*/

const char* sf_strerror (SNDFILE *sndfile);


/* sf_error_number () allows the retrieval of the error string for each internal
 * error number.
 *
*/

const char* sf_error_number (int errnum);


/* The following two error functions are deprecated but they will remain in the
 * library for the foreseeable future. The function sf_strerror() should be used
 * in their place.
*/

int sf_perror (SNDFILE *sndfile);
int sf_error_str (SNDFILE *sndfile, char* str, size_t len);


/* Allow the caller to retrieve information from or change aspects of the
 * library behaviour.
*/

int sf_command (SNDFILE *sndfile, int command, void *data, int datasize);


/* Return TRUE if fields of the SF_INFO struct are a valid combination of values. */

int sf_format_check (const SF_INFO *info);


/* Seek within the waveform data chunk of the SNDFILE. sf_seek () uses
 * the same values for whence (SEEK_SET, SEEK_CUR and SEEK_END) as
 * stdio.h function fseek ().
 * An offset of zero with whence set to SEEK_SET will position the
 * read / write pointer to the first data sample.
 * On success sf_seek returns the current position in (multi-channel)
 * samples from the start of the file.
 * Please see the libsndfile documentation for moving the read pointer
 * separately from the write pointer on files open in mode SFM_RDWR.
 * On error all of these functions return -1.
*/

enum {
    SF_SEEK_SET = SEEK_SET,
    SF_SEEK_CUR = SEEK_CUR,
    SF_SEEK_END = SEEK_END
};

sf_count_t sf_seek (SNDFILE *sndfile, sf_count_t frames, int whence);

/* Functions for retrieving and setting string data within sound files.
 * Not all file types support this features; AIFF and WAV do. For both
 * functions, the str_type parameter must be one of the SF_STR_* values
 * defined above.
 * On error, sf_set_string() returns non-zero while sf_get_string()
 * returns NULL.
*/

int sf_set_string (SNDFILE *sndfile, int str_type, const char* str);

const char* sf_get_string (SNDFILE *sndfile, int str_type);


/* Return the library version string. */

const char * sf_version_string (void);

/* Return the current byterate at this point in the file. The byte rate in this
 * case is the number of bytes per second of audio data. For instance, for a
 * stereo, 18 bit PCM encoded file with an 16kHz sample rate, the byte rate
 * would be 2 (stereo) * 2 (two bytes per sample) * 16000 => 64000 bytes/sec.
 * For some file formats the returned value will be accurate and exact, for some
 * it will be a close approximation, for some it will be the average bitrate for
 * the whole file and for some it will be a time varying value that was accurate
 * when the file was most recently read or written.
 * To get the bitrate, multiple this value by 8.
 * Returns -1 for unknown.
*/
int sf_current_byterate (SNDFILE *sndfile);

/* Functions for reading/writing the waveform data of a sound file.
*/

sf_count_t sf_read_raw (SNDFILE *sndfile, void *ptr, sf_count_t bytes);
sf_count_t sf_write_raw (SNDFILE *sndfile, const void *ptr, sf_count_t bytes);

/* Functions for reading and writing the data chunk in terms of frames.
 * The number of items actually read/written = frames * number of channels.
 * sf_xxxx_raw read/writes the raw data bytes from/to the file
 * sf_xxxx_short passes data in the native short format
 * sf_xxxx_int passes data in the native int format
 * sf_xxxx_float passes data in the native float format
 * sf_xxxx_double passes data in the native double format
 * All of these read/write function return number of frames read/written.
*/

sf_count_t sf_readf_short (SNDFILE *sndfile, short *ptr, sf_count_t frames);
sf_count_t sf_writef_short (SNDFILE *sndfile, const short *ptr, sf_count_t frames);

sf_count_t sf_readf_int (SNDFILE *sndfile, int *ptr, sf_count_t frames);
sf_count_t sf_writef_int (SNDFILE *sndfile, const int *ptr, sf_count_t frames);

sf_count_t sf_readf_float (SNDFILE *sndfile, float *ptr, sf_count_t frames);
sf_count_t sf_writef_float (SNDFILE *sndfile, const float *ptr, sf_count_t frames);

sf_count_t sf_readf_double (SNDFILE *sndfile, double *ptr, sf_count_t frames);
sf_count_t sf_writef_double (SNDFILE *sndfile, const double *ptr, sf_count_t frames);


/* Functions for reading and writing the data chunk in terms of items.
 * Otherwise similar to above.
 * All of these read/write function return number of items read/written.
*/

sf_count_t sf_read_short (SNDFILE *sndfile, short *ptr, sf_count_t items);
sf_count_t sf_write_short (SNDFILE *sndfile, const short *ptr, sf_count_t items);

sf_count_t sf_read_int (SNDFILE *sndfile, int *ptr, sf_count_t items);
sf_count_t sf_write_int (SNDFILE *sndfile, const int *ptr, sf_count_t items);

sf_count_t sf_read_float (SNDFILE *sndfile, float *ptr, sf_count_t items);
sf_count_t sf_write_float (SNDFILE *sndfile, const float *ptr, sf_count_t items);

sf_count_t sf_read_double (SNDFILE *sndfile, double *ptr, sf_count_t items);
sf_count_t sf_write_double (SNDFILE *sndfile, const double *ptr, sf_count_t items);


/* Close the SNDFILE and clean up all memory allocations associated with this
 * file.
 * Returns 0 on success, or an error number.
*/

int sf_close (SNDFILE *sndfile);


/* If the file is opened SFM_WRITE or SFM_RDWR, call fsync() on the file
 * to force the writing of data to disk. If the file is opened SFM_READ
 * no action is taken.
*/

void sf_write_sync (SNDFILE *sndfile);

/* The function sf_wchar_open() is Windows Only!
 * Open a file passing in a Windows Unicode filename. Otherwise, this is
 * the same as sf_open().
*/

#ifdef _WIN32
SNDFILE* sf_wchar_open (const wchar_t *wpath, int mode, SF_INFO *sfinfo);
#endif

/* Getting and setting of chunks from within a sound file.
 *
 * These functions allow the getting and setting of chunks within a sound file
 * (for those formats which allow it).
 *
 * These functions fail safely. Specifically, they will not allow you to overwrite
 * existing chunks or add extra versions of format specific reserved chunks but
 * should allow you to retrieve any and all chunks (may not be implemented for
 * all chunks or all file formats).
*/

struct SF_CHUNK_INFO {
    char id [64]; /* The chunk identifier. */
    unsigned id_size; /* The size of the chunk identifier. */
    unsigned datalen; /* The size of that data. */
    void *data; /* Pointer to the data. */
};

typedef struct SF_CHUNK_INFO SF_CHUNK_INFO;

/* Set the specified chunk info (must be done before any audio data is written
 * to the file). This will fail for format specific reserved chunks.
 * The chunk_info->data pointer must be valid until the file is closed.
 * Returns SF_ERR_NO_ERROR on success or non-zero on failure.
*/
int sf_set_chunk (SNDFILE * sndfile, const SF_CHUNK_INFO * chunk_info);

/*
 * An opaque structure to an iterator over the all chunks of a given id
*/
typedef struct SF_CHUNK_ITERATOR SF_CHUNK_ITERATOR;

/* Get an iterator for all chunks matching chunk_info.
 * The iterator will point to the first chunk matching chunk_info.
 * Chunks are matching, if (chunk_info->id) matches the first
 * (chunk_info->id_size) bytes of a chunk found in the SNDFILE* handle.
 * If chunk_info is NULL, an iterator to all chunks in the SNDFILE* handle
 * is returned.
 * The values of chunk_info->datalen and chunk_info->data are ignored.
 * If no matching chunks are found in the sndfile, NULL is returned.
 * The returned iterator will stay valid until one of the following occurs
 * a) The sndfile is closed.
 * b) A new chunk is added using sf_set_chunk().
 * c) Another chunk iterator function is called on the same SNDFILE* handle
 * that causes the iterator to be modified.
 * The memory for the iterator belongs to the SNDFILE* handle and is freed when
 * sf_close() is called.
*/
SF_CHUNK_ITERATOR * sf_get_chunk_iterator (SNDFILE * sndfile, const SF_CHUNK_INFO * chunk_info);

/* Iterate through chunks by incrementing the iterator.
 * Increments the iterator and returns a handle to the new one.
 * After this call, iterator will no longer be valid, and you must use the
 * newly returned handle from now on.
 * The returned handle can be used to access the next chunk matching
 * the criteria as defined in sf_get_chunk_iterator().
 * If iterator points to the last chunk, this will free all resources
 * associated with iterator and return NULL.
 * The returned iterator will stay valid until sf_get_chunk_iterator_next
 * is called again, the sndfile is closed or a new chunk us added.
*/
SF_CHUNK_ITERATOR * sf_next_chunk_iterator (SF_CHUNK_ITERATOR * iterator);

/* Get the size of the specified chunk.
 * If the specified chunk exists, the size will be returned in the
 * datalen field of the SF_CHUNK_INFO struct.
 * Additionally, the id of the chunk will be copied to the id
 * field of the SF_CHUNK_INFO struct and it's id_size field will
 * be updated accordingly.
 * If the chunk doesn't exist chunk_info->datalen will be zero, and the
 * id and id_size fields will be undefined.
 * The function will return SF_ERR_NO_ERROR on success or non-zero on
 * failure.
*/
int sf_get_chunk_size (const SF_CHUNK_ITERATOR * it, SF_CHUNK_INFO * chunk_info);

/* Get the specified chunk data.
 * If the specified chunk exists, up to chunk_info->datalen bytes of
 * the chunk data will be copied into the chunk_info->data buffer
 * (allocated by the caller) and the chunk_info->datalen field
 * updated to reflect the size of the data. The id and id_size
 * field will be updated according to the retrieved chunk
 * If the chunk doesn't exist chunk_info->datalen will be zero, and the
 * id and id_size fields will be undefined.
 * The function will return SF_ERR_NO_ERROR on success or non-zero on
 * failure.
*/
int sf_get_chunk_data (const SF_CHUNK_ITERATOR * it, SF_CHUNK_INFO * chunk_info);

#ifdef __cplusplus
} /* extern "C" */
#endif /* __cplusplus */

#endif /* SNDFILE_H */