switch_module_interfaces.h

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/* 
 * FreeSWITCH Modular Media Switching Software Library / Soft-Switch Application
 * Copyright (C) 2005-2014, Anthony Minessale II <anthm@freeswitch.org>
 *
 * Version: MPL 1.1
 *
 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is FreeSWITCH Modular Media Switching Software Library / Soft-Switch Application
 *
 * The Initial Developer of the Original Code is
 * Anthony Minessale II <anthm@freeswitch.org>
 * Portions created by the Initial Developer are Copyright (C)
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 * 
 * Anthony Minessale II <anthm@freeswitch.org>
 * Luke Dashjr <luke@openmethods.com> (OpenMethods, LLC)
 *
 *
 * switch_module_interfaces.h -- Module Interface Definitions
 *
 */
/*! \file switch_module_interfaces.h
  \brief Module Interface Definitions

  This module holds the definition of data abstractions used to implement various pluggable 
  interfaces and pluggable event handlers.

*/
#ifndef SWITCH_MODULE_INTERFACES_H
#define SWITCH_MODULE_INTERFACES_H

#include <switch.h>
#include "switch_resample.h"

SWITCH_BEGIN_EXTERN_C
/*! \brief A table of functions to execute at various states 
 */
        typedef enum {
        SWITCH_SHN_ON_INIT,
        SWITCH_SHN_ON_ROUTING,
        SWITCH_SHN_ON_EXECUTE,
        SWITCH_SHN_ON_HANGUP,
        SWITCH_SHN_ON_EXCHANGE_MEDIA,
        SWITCH_SHN_ON_SOFT_EXECUTE,
        SWITCH_SHN_ON_CONSUME_MEDIA,
        SWITCH_SHN_ON_HIBERNATE,
        SWITCH_SHN_ON_RESET,
        SWITCH_SHN_ON_PARK,
        SWITCH_SHN_ON_REPORTING,
        SWITCH_SHN_ON_DESTROY
} switch_state_handler_name_t;

struct switch_state_handler_table {
        /*! executed when the state changes to init */
        switch_state_handler_t on_init;
        /*! executed when the state changes to routing */
        switch_state_handler_t on_routing;
        /*! executed when the state changes to execute */
        switch_state_handler_t on_execute;
        /*! executed when the state changes to hangup */
        switch_state_handler_t on_hangup;
        /*! executed when the state changes to exchange_media */
        switch_state_handler_t on_exchange_media;
        /*! executed when the state changes to soft_execute */
        switch_state_handler_t on_soft_execute;
        /*! executed when the state changes to consume_media */
        switch_state_handler_t on_consume_media;
        /*! executed when the state changes to hibernate */
        switch_state_handler_t on_hibernate;
        /*! executed when the state changes to reset */
        switch_state_handler_t on_reset;
        /*! executed when the state changes to park */
        switch_state_handler_t on_park;
        /*! executed when the state changes to reporting */
        switch_state_handler_t on_reporting;
        /*! executed when the state changes to destroy */
        switch_state_handler_t on_destroy;
        int flags;
        void *padding[10];
};

struct switch_stream_handle {
        switch_stream_handle_read_function_t read_function;
        switch_stream_handle_write_function_t write_function;
        switch_stream_handle_raw_write_function_t raw_write_function;
        void *data;
        void *end;
        switch_size_t data_size;
        switch_size_t data_len;
        switch_size_t alloc_len;
        switch_size_t alloc_chunk;
        switch_event_t *param_event;
};

struct switch_io_event_hooks;
struct switch_say_file_handle;

typedef switch_call_cause_t (*switch_io_outgoing_channel_t)     
        (switch_core_session_t *, switch_event_t *, switch_caller_profile_t *, switch_core_session_t **, switch_memory_pool_t **, switch_originate_flag_t,
         switch_call_cause_t *);
typedef switch_status_t (*switch_io_read_frame_t) (switch_core_session_t *, switch_frame_t **, switch_io_flag_t, int);
typedef switch_status_t (*switch_io_write_frame_t) (switch_core_session_t *, switch_frame_t *, switch_io_flag_t, int);
typedef switch_status_t (*switch_io_kill_channel_t) (switch_core_session_t *, int);
typedef switch_status_t (*switch_io_send_dtmf_t) (switch_core_session_t *, const switch_dtmf_t *);
typedef switch_status_t (*switch_io_receive_message_t) (switch_core_session_t *, switch_core_session_message_t *);
typedef switch_status_t (*switch_io_receive_event_t) (switch_core_session_t *, switch_event_t *);
typedef switch_status_t (*switch_io_state_change_t) (switch_core_session_t *);
typedef switch_status_t (*switch_io_state_run_t) (switch_core_session_t *);
typedef switch_status_t (*switch_io_read_video_frame_t) (switch_core_session_t *, switch_frame_t **, switch_io_flag_t, int);
typedef switch_status_t (*switch_io_write_video_frame_t) (switch_core_session_t *, switch_frame_t *, switch_io_flag_t, int);
typedef switch_jb_t *(*switch_io_get_jb_t) (switch_core_session_t *, switch_media_type_t);

typedef enum {
        SWITCH_IO_OUTGOING_CHANNEL,
        SWITCH_IO_READ_FRAME,
        SWITCH_IO_WRITE_FRAME,
        SWITCH_IO_KILL_CHANNEL,
        SWITCH_IO_SEND_DTMF,
        SWITCH_IO_RECEIVE_MESSAGE,
        SWITCH_IO_RECEIVE_EVENT,
        SWITCH_IO_STATE_CHANGE,
        SWITCH_IO_READ_VIDEO_FRAME,
        SWITCH_IO_WRITE_VIDEO_FRAME,
        SWITCH_IO_GET_JB,
} switch_io_routine_name_t;

/*! \brief A table of i/o routines that an endpoint interface can implement */
struct switch_io_routines {
        /*! creates an outgoing session from given session, caller profile */
        switch_io_outgoing_channel_t outgoing_channel;
        /*! read a frame from a session */
        switch_io_read_frame_t read_frame;
        /*! write a frame to a session */
        switch_io_write_frame_t write_frame;
        /*! send a kill signal to the session's channel */
        switch_io_kill_channel_t kill_channel;
        /*! send a string of DTMF digits to a session's channel */
        switch_io_send_dtmf_t send_dtmf;
        /*! receive a message from another session */
        switch_io_receive_message_t receive_message;
        /*! queue a message for another session */
        switch_io_receive_event_t receive_event;
        /*! change a sessions channel state */
        switch_io_state_change_t state_change;
        /*! read a video frame from a session */
        switch_io_read_video_frame_t read_video_frame;
        /*! write a video frame to a session */
        switch_io_write_video_frame_t write_video_frame;
        /*! change a sessions channel run state */
        switch_io_state_run_t state_run;
        /*! get sessions jitterbuffer */
        switch_io_get_jb_t get_jb;
        void *padding[10];
};

/*! \brief Abstraction of an module endpoint interface
  This is the glue between the abstract idea of a "channel" and what is really going on under the
  hood.  Each endpoint module fills out one of these tables and makes it available when a channel
  is created of it's paticular type.
*/

struct switch_endpoint_interface {
        /*! the interface's name */
        const char *interface_name;

        /*! channel abstraction methods */
        switch_io_routines_t *io_routines;

        /*! state machine methods */
        switch_state_handler_table_t *state_handler;

        /*! private information */
        void *private_info;

        switch_thread_rwlock_t *rwlock;
        int refs;
        switch_mutex_t *reflock;

        /* parent */
        switch_loadable_module_interface_t *parent;

        /* to facilitate linking */
        struct switch_endpoint_interface *next;

        switch_core_recover_callback_t recover_callback;

};

/*! \brief Abstract handler to a timer module */
struct switch_timer {
        /*! time interval expressed in milliseconds */
        int interval;
        /*! flags to control behaviour */
        uint32_t flags;
        /*! sample count to increment by on each cycle */
        unsigned int samples;
        /*! current sample count based on samples parameter */
        uint32_t samplecount;
        /*! the timer interface provided from a loadable module */
        switch_timer_interface_t *timer_interface;
        /*! the timer's memory pool */
        switch_memory_pool_t *memory_pool;
        /*! private data for loadable modules to store information */
        void *private_info;
        /*! remaining time from last call to _check() */
        switch_size_t diff;
        switch_time_t start;
        uint64_t tick;

};

typedef enum {
        SWITCH_TIMER_FUNC_TIMER_INIT,
        SWITCH_TIMER_FUNC_TIMER_NEXT,
        SWITCH_TIMER_FUNC_TIMER_STEP,
        SWITCH_TIMER_FUNC_TIMER_SYNC,
        SWITCH_TIMER_FUNC_TIMER_CHECK,
        SWITCH_TIMER_FUNC_TIMER_DESTROY
} switch_timer_func_name_t;

/*! \brief A table of functions that a timer module implements */
struct switch_timer_interface {
        /*! the name of the interface */
        const char *interface_name;
        /*! function to allocate the timer */
        switch_status_t (*timer_init) (switch_timer_t *);
        /*! function to wait for one cycle to pass */
        switch_status_t (*timer_next) (switch_timer_t *);
        /*! function to step the timer one step */
        switch_status_t (*timer_step) (switch_timer_t *);
        /*! function to reset the timer  */
        switch_status_t (*timer_sync) (switch_timer_t *);
        /*! function to check if the current step has expired */
        switch_status_t (*timer_check) (switch_timer_t *, switch_bool_t);
        /*! function to deallocate the timer */
        switch_status_t (*timer_destroy) (switch_timer_t *);
        switch_thread_rwlock_t *rwlock;
        int refs;
        switch_mutex_t *reflock;
        switch_loadable_module_interface_t *parent;
        struct switch_timer_interface *next;
};

/*! \brief Abstract interface to a dialplan module */
struct switch_dialplan_interface {
        /*! the name of the interface */
        const char *interface_name;
        /*! the function to read an extension and set a channels dialpan */
        switch_dialplan_hunt_function_t hunt_function;
        switch_thread_rwlock_t *rwlock;
        int refs;
        switch_mutex_t *reflock;
        switch_loadable_module_interface_t *parent;
        struct switch_dialplan_interface *next;
};

/*! \brief Abstract interface to a file format module */
struct switch_file_interface {
        /*! the name of the interface */
        const char *interface_name;
        /*! function to open the file */
        switch_status_t (*file_open) (switch_file_handle_t *, const char *file_path);
        /*! function to close the file */
        switch_status_t (*file_close) (switch_file_handle_t *);
        /*! function to close the file */
        switch_status_t (*file_truncate) (switch_file_handle_t *, int64_t offset);
        /*! function to read from the file */
        switch_status_t (*file_read) (switch_file_handle_t *, void *data, switch_size_t *len);
        /*! function to write from the file */
        switch_status_t (*file_write) (switch_file_handle_t *, void *data, switch_size_t *len);
        /*! function to seek to a certian position in the file */
        switch_status_t (*file_read_video) (switch_file_handle_t *, switch_frame_t *frame, switch_video_read_flag_t flags);
        /*! function to write from the file */
        switch_status_t (*file_write_video) (switch_file_handle_t *, switch_frame_t *frame);
        /*! function to seek to a certian position in the file */
        switch_status_t (*file_seek) (switch_file_handle_t *, unsigned int *cur_pos, int64_t samples, int whence);
        /*! function to set meta data */
        switch_status_t (*file_set_string) (switch_file_handle_t *fh, switch_audio_col_t col, const char *string);
        /*! function to get meta data */
        switch_status_t (*file_get_string) (switch_file_handle_t *fh, switch_audio_col_t col, const char **string);
        /*! function to control the underlying tech of the file  */
        switch_status_t (*file_command) (switch_file_handle_t *fh, switch_file_command_t command);
        /*! list of supported file extensions */
        char **extens;
        switch_thread_rwlock_t *rwlock;
        int refs;
        switch_mutex_t *reflock;
        switch_loadable_module_interface_t *parent;
        struct switch_file_interface *next;
};

typedef enum {
        SWITCH_VIDEO_ENCODE_SPEED_DEFAULT = 0,
        SWITCH_VIDEO_ENCODE_SPEED_FAST = 0,
        SWITCH_VIDEO_ENCODE_SPEED_MEDIUM,
        SWITCH_VIDEO_ENCODE_SPEED_SLOW
} switch_video_encode_speed_t;

typedef enum {
        SWITCH_VIDEO_PROFILE_BASELINE,
        SWITCH_VIDEO_PROFILE_MAIN,
        SWITCH_VIDEO_PROFILE_HIGH
} switch_video_profile_t;

typedef struct switch_mm_s {
        int samplerate;
        int channels;
        int keyint;
        int ab;
        int vb;
        int vw;
        int vh;
        float fps;
        float source_fps;
        int vbuf;
        switch_video_profile_t vprofile;
        switch_video_encode_speed_t vencspd;
        uint8_t try_hardware_encoder;
} switch_mm_t;

/*! an abstract representation of a file handle (some parameters based on compat with libsndfile) */
struct switch_file_handle {
        /*! the interface of the module that implemented the current file type */
        switch_file_interface_t *file_interface;
        /*! flags to control behaviour */
        uint32_t flags;
        /*! a file descriptor if neceessary */
        switch_file_t *fd;
        /*! samples position of the handle */
        unsigned int samples;
        /*! the current samplerate */
        uint32_t samplerate;
        /*! the current native samplerate */
        uint32_t native_rate;
        /*! the number of channels */
        uint32_t channels;
        uint32_t real_channels;
        /*! integer representation of the format */
        unsigned int format;
        /*! integer representation of the sections */
        unsigned int sections;
        /*! is the file seekable */
        int seekable;
        /*! the sample count of the file */
        switch_size_t sample_count;
        /*! the speed of the file playback */
        int speed;
        /*! the handle's memory pool */
        switch_memory_pool_t *memory_pool;
        /*! pre-buffer x bytes for streams */
        uint32_t prebuf;
        /*! private data for the format module to store handle specific info */
        uint32_t interval;
        void *private_info;
        char *handler;
        int64_t pos;
        switch_buffer_t *audio_buffer;
        switch_buffer_t *sp_audio_buffer;
        uint32_t thresh;
        uint32_t silence_hits;
        uint32_t offset_pos;
        switch_size_t samples_in;
        switch_size_t samples_out;
        int32_t vol;
        switch_audio_resampler_t *resampler;
        switch_buffer_t *buffer;
        switch_byte_t *dbuf;
        switch_size_t dbuflen;
        switch_buffer_t *pre_buffer;
        unsigned char *pre_buffer_data;
        switch_size_t pre_buffer_datalen;
        const char *file;
        const char *func;
        int line;
        char *file_path;
        char *spool_path;
        const char *prefix;
        int max_samples;
        switch_event_t *params;
        uint32_t cur_channels;
        uint32_t cur_samplerate;
        char *stream_name;
        char *modname;
        switch_mm_t mm;
        switch_mutex_t *flag_mutex;
        /*! total video duration, or total page in pdf*/
        int64_t duration;
        /*! current video position, or current page in pdf */
        int64_t vpos;
};

/*! \brief Abstract interface to an asr module */
struct switch_asr_interface {
        /*! the name of the interface */
        const char *interface_name;
        /*! function to open the asr interface */
        switch_status_t (*asr_open) (switch_asr_handle_t *ah, const char *codec, int rate, const char *dest, switch_asr_flag_t *flags);
        /*! function to load a grammar to the asr interface */
        switch_status_t (*asr_load_grammar) (switch_asr_handle_t *ah, const char *grammar, const char *name);
        /*! function to unload a grammar to the asr interface */
        switch_status_t (*asr_unload_grammar) (switch_asr_handle_t *ah, const char *name);
        /*! function to close the asr interface */
        switch_status_t (*asr_close) (switch_asr_handle_t *ah, switch_asr_flag_t *flags);
        /*! function to feed audio to the ASR */
        switch_status_t (*asr_feed) (switch_asr_handle_t *ah, void *data, unsigned int len, switch_asr_flag_t *flags);
        /*! function to resume the ASR */
        switch_status_t (*asr_resume) (switch_asr_handle_t *ah);
        /*! function to pause the ASR */
        switch_status_t (*asr_pause) (switch_asr_handle_t *ah);
        /*! function to read results from the ASR */
        switch_status_t (*asr_check_results) (switch_asr_handle_t *ah, switch_asr_flag_t *flags);
        /*! function to read results from the ASR */
        switch_status_t (*asr_get_results) (switch_asr_handle_t *ah, char **xmlstr, switch_asr_flag_t *flags);
        /*! function to read result headers from the ASR */
        switch_status_t (*asr_get_result_headers) (switch_asr_handle_t *ah, switch_event_t **headers, switch_asr_flag_t *flags);
        /*! function to start ASR input timers */
        switch_status_t (*asr_start_input_timers) (switch_asr_handle_t *ah);
        void (*asr_text_param) (switch_asr_handle_t *ah, char *param, const char *val);
        void (*asr_numeric_param) (switch_asr_handle_t *ah, char *param, int val);
        void (*asr_float_param) (switch_asr_handle_t *ah, char *param, double val);
        switch_thread_rwlock_t *rwlock;
        int refs;
        switch_mutex_t *reflock;
        switch_loadable_module_interface_t *parent;
        struct switch_asr_interface *next;
        /*! function to enable a grammar to the asr interface */
        switch_status_t (*asr_enable_grammar) (switch_asr_handle_t *ah, const char *name);
        /*! function to disable a grammar to the asr interface */
        switch_status_t (*asr_disable_grammar) (switch_asr_handle_t *ah, const char *name);
        /*! function to disable all grammars to the asr interface */
        switch_status_t (*asr_disable_all_grammars) (switch_asr_handle_t *ah);
        /*! function to feed DTMF to the ASR */
        switch_status_t (*asr_feed_dtmf) (switch_asr_handle_t *ah, const switch_dtmf_t *dtmf, switch_asr_flag_t *flags);
};

/*! an abstract representation of an asr speech interface. */
struct switch_asr_handle {
        /*! the interface of the module that implemented the current speech interface */
        switch_asr_interface_t *asr_interface;
        /*! flags to control behaviour */
        uint32_t flags;
        /*! The Name */
        char *name;
        /*! The Codec */
        char *codec;
        /*! The Rate */
        uint32_t rate;
        char *grammar;
        /*! module specific param */
        char *param;
        /*! the handle's memory pool */
        switch_memory_pool_t *memory_pool;
        switch_buffer_t *buffer;
        switch_byte_t *dbuf;
        switch_size_t dbuflen;
        switch_audio_resampler_t *resampler;
        /*! the current samplerate */
        uint32_t samplerate;
        /*! the current native samplerate */
        uint32_t native_rate;
        /*! private data for the format module to store handle specific info */
        void *private_info;
};

/*! \brief Abstract interface to a speech module */
struct switch_speech_interface {
        /*! the name of the interface */
        const char *interface_name;
        /*! function to open the speech interface */
        switch_status_t (*speech_open) (switch_speech_handle_t *sh, const char *voice_name, int rate, int channels, switch_speech_flag_t *flags);
        /*! function to close the speech interface */
        switch_status_t (*speech_close) (switch_speech_handle_t *, switch_speech_flag_t *flags);
        /*! function to feed audio to the ASR */
        switch_status_t (*speech_feed_tts) (switch_speech_handle_t *sh, char *text, switch_speech_flag_t *flags);
        /*! function to read audio from the TTS */
        switch_status_t (*speech_read_tts) (switch_speech_handle_t *sh, void *data, switch_size_t *datalen, switch_speech_flag_t *flags);
        void (*speech_flush_tts) (switch_speech_handle_t *sh);
        void (*speech_text_param_tts) (switch_speech_handle_t *sh, char *param, const char *val);
        void (*speech_numeric_param_tts) (switch_speech_handle_t *sh, char *param, int val);
        void (*speech_float_param_tts) (switch_speech_handle_t *sh, char *param, double val);
        switch_thread_rwlock_t *rwlock;
        int refs;
        switch_mutex_t *reflock;
        switch_loadable_module_interface_t *parent;
        struct switch_speech_interface *next;
};


/*! an abstract representation of a tts speech interface. */
struct switch_speech_handle {
        /*! the interface of the module that implemented the current speech interface */
        switch_speech_interface_t *speech_interface;
        /*! flags to control behaviour */
        uint32_t flags;
        /*! The Name */
        char *name;
        /*! The Rate */
        uint32_t rate;
        uint32_t speed;
        uint32_t samples;
        uint32_t channels;
        uint32_t real_channels;
        char voice[80];
        char *engine;
        /*! module specific param */
        char *param;
        /*! the handle's memory pool */
        switch_memory_pool_t *memory_pool;
        switch_audio_resampler_t *resampler;
        switch_buffer_t *buffer;
        switch_byte_t *dbuf;
        switch_size_t dbuflen;
        /*! the current samplerate */
        uint32_t samplerate;
        /*! the current native samplerate */
        uint32_t native_rate;
        /*! the number of channels */

        /*! private data for the format module to store handle specific info */
        void *private_info;
};

/*! \brief Abstract interface to a say module */
struct switch_say_interface {
        /*! the name of the interface */
        const char *interface_name;
        /*! function to pass down to the module */
        switch_say_callback_t say_function;
        switch_say_string_callback_t say_string_function;
        switch_thread_rwlock_t *rwlock;
        int refs;
        switch_mutex_t *reflock;
        switch_loadable_module_interface_t *parent;
        struct switch_say_interface *next;
};

/*! \brief Abstract interface to a chat module */
struct switch_chat_interface {
        /*! the name of the interface */
        const char *interface_name;
        /*! function to open the directory interface */
        switch_status_t (*chat_send) (switch_event_t *message_event);
                                                                  
        switch_thread_rwlock_t *rwlock;
        int refs;
        switch_mutex_t *reflock;
        switch_loadable_module_interface_t *parent;
        struct switch_chat_interface *next;
};

/*! \brief Abstract interface to a management module */
struct switch_management_interface {
        /*! the name of the interface */
        const char *relative_oid;
        /*! function to open the directory interface */
        switch_status_t (*management_function) (char *relative_oid, switch_management_action_t action, char *data, switch_size_t datalen);
        switch_thread_rwlock_t *rwlock;
        int refs;
        switch_mutex_t *reflock;
        switch_loadable_module_interface_t *parent;
        struct switch_management_interface *next;
};

/*! \brief Abstract interface to a limit module */
struct switch_limit_interface {
        /*! name of the interface */
        const char *interface_name;
        /*! increment */
        switch_status_t (*incr) (switch_core_session_t *session, const char *realm, const char *resource, const int max, const int interval);
        /*! release */
        switch_status_t (*release) (switch_core_session_t *session, const char *realm, const char *resource);
        /*! usage for resource */
        int (*usage) (const char *realm, const char *resource, uint32_t *rcount);
        /*! reset counters */
        switch_status_t (*reset) (void);
        /*! freform status */
        char * (*status) (void);
        /*! reset interval counter */
        switch_status_t (*interval_reset) (const char *realm, const char *resource);
        /* internal */
        switch_thread_rwlock_t *rwlock;
        int refs;
        switch_mutex_t *reflock;
        switch_loadable_module_interface_t *parent;
        struct switch_limit_interface *next;
};

/*! \brief Abstract interface to a directory module */
struct switch_directory_interface {
        /*! the name of the interface */
        const char *interface_name;
        /*! function to open the directory interface */
        switch_status_t (*directory_open) (switch_directory_handle_t *dh, char *source, char *dsn, char *passwd);
        /*! function to close the directory interface */
        switch_status_t (*directory_close) (switch_directory_handle_t *dh);
        /*! function to query the directory interface */
        switch_status_t (*directory_query) (switch_directory_handle_t *dh, char *base, char *query);
        /*! function to advance to the next record */
        switch_status_t (*directory_next) (switch_directory_handle_t *dh);
        /*! function to advance to the next name/value pair in the current record */
        switch_status_t (*directory_next_pair) (switch_directory_handle_t *dh, char **var, char **val);
        switch_thread_rwlock_t *rwlock;
        int refs;
        switch_mutex_t *reflock;
        switch_loadable_module_interface_t *parent;
        struct switch_directory_interface *next;
};

/*! an abstract representation of a directory interface. */
struct switch_directory_handle {
        /*! the interface of the module that implemented the current directory interface */
        switch_directory_interface_t *directory_interface;
        /*! flags to control behaviour */
        uint32_t flags;

        /*! the handle's memory pool */
        switch_memory_pool_t *memory_pool;
        /*! private data for the format module to store handle specific info */
        void *private_info;
};

struct switch_audio_codec_settings {
        int unused;
};

struct switch_video_codec_settings {
        uint32_t bandwidth;
        int32_t width;
        int32_t height;
        uint8_t try_hardware_encoder;
};

union switch_codec_settings {
        struct switch_audio_codec_settings audio;
        struct switch_video_codec_settings video;
};

/*! an abstract handle of a fmtp parsed by codec */
struct switch_codec_fmtp {
        /*! actual samples transferred per second for those who are not moron g722 RFC writers */
        uint32_t actual_samples_per_second;
        /*! bits transferred per second */
        int bits_per_second;
        /*! number of microseconds of media in one packet (ptime * 1000) */
        int microseconds_per_packet;
        /*! stereo  */
        int stereo;
        /*! private data for the codec module to store handle specific info */
        void *private_info;

};

struct switch_picture {
        uint32_t width;      /* the picture width */
        uint32_t height;     /* the picture height */
        uint8_t *planes[4];  /* pointer to the top left pixel for each plane */
        uint32_t stride[4];  /* stride between rows for each plane */
};

/*! an abstract handle to a codec module */
struct switch_codec {
        /*! the codec interface table this handle uses */
        switch_codec_interface_t *codec_interface;
        /*! the specific implementation of the above codec */
        const switch_codec_implementation_t *implementation;
        /*! fmtp line from remote sdp */
        char *fmtp_in;
        /*! fmtp line for local sdp */
        char *fmtp_out;
        /*! flags to modify behaviour */
        uint32_t flags;
        /*! the handle's memory pool */
        switch_memory_pool_t *memory_pool;
        /*! private data for the codec module to store handle specific info */
        void *private_info;
        switch_payload_t agreed_pt;
        switch_mutex_t *mutex;
        struct switch_codec *next;
        switch_core_session_t *session;
        switch_frame_t *cur_frame;
};

/*! \brief A table of settings and callbacks that define a paticular implementation of a codec */
struct switch_codec_implementation {
        /*! enumeration defining the type of the codec */
        switch_codec_type_t codec_type;
        /*! the IANA code number */
        switch_payload_t ianacode;
        /*! the IANA code name */
        char *iananame;
        /*! default fmtp to send (can be overridden by the init function) */
        char *fmtp;
        /*! samples transferred per second */
        uint32_t samples_per_second;
        /*! actual samples transferred per second for those who are not moron g722 RFC writers */
        uint32_t actual_samples_per_second;
        /*! bits transferred per second */
        int bits_per_second;
        /*! number of microseconds of media in one packet (ptime * 1000) */
        int microseconds_per_packet;
        /*! number of samples in one packet */
        uint32_t samples_per_packet;
        /*! number of bytes one packet will decompress to */
        uint32_t decoded_bytes_per_packet;
        /*! number of encoded bytes in the RTP payload */
        uint32_t encoded_bytes_per_packet;
        /*! number of channels represented */
        uint8_t number_of_channels;
        /*! number of codec frames packetized into one packet */
        int codec_frames_per_packet;
        /*! function to initialize a codec handle using this implementation */
        switch_core_codec_init_func_t init;
        /*! function to encode raw data into encoded data */
        switch_core_codec_encode_func_t encode;
        /*! function to decode encoded data into raw data */
        switch_core_codec_decode_func_t decode;
        /*! function to encode video raw data into encoded data */
        switch_core_codec_video_encode_func_t encode_video;
        /*! function to decode video encoded data into raw data */
        switch_core_codec_video_decode_func_t decode_video;
        /*! function to send control messages to the codec */
        switch_core_codec_control_func_t codec_control;
        /*! deinitalize a codec handle using this implementation */
        switch_core_codec_destroy_func_t destroy;
        uint32_t codec_id;
        uint32_t impl_id;
        char *modname;
        struct switch_codec_implementation *next;
};

/*! \brief Top level module interface to implement a series of codec implementations */
struct switch_codec_interface {
        /*! the name of the interface */
        const char *interface_name;
        /*! a list of codec implementations related to the codec */
        switch_codec_implementation_t *implementations;
        /*! function to decode a codec fmtp parameters */
        switch_core_codec_fmtp_parse_func_t parse_fmtp;
        uint32_t codec_id;
        switch_thread_rwlock_t *rwlock;
        int refs;
        switch_mutex_t *reflock;
        char *modname;
        switch_loadable_module_interface_t *parent;
        struct switch_codec_interface *next;
};

/*! \brief A module interface to implement an application */
struct switch_application_interface {
        /*! the name of the interface */
        const char *interface_name;
        /*! function the application implements */
        switch_application_function_t application_function;
        /*! the long winded description of the application */
        const char *long_desc;
        /*! the short and sweet description of the application */
        const char *short_desc;
        /*! an example of the application syntax */
        const char *syntax;
        /*! flags to control behaviour */
        uint32_t flags;
        switch_thread_rwlock_t *rwlock;
        int refs;
        switch_mutex_t *reflock;
        switch_loadable_module_interface_t *parent;
        struct switch_application_interface *next;
};

/*! \brief A module interface to implement a chat application */
struct switch_chat_application_interface {
        /*! the name of the interface */
        const char *interface_name;
        /*! function the application implements */
        switch_chat_application_function_t chat_application_function;
        /*! the long winded description of the application */
        const char *long_desc;
        /*! the short and sweet description of the application */
        const char *short_desc;
        /*! an example of the application syntax */
        const char *syntax;
        /*! flags to control behaviour */
        uint32_t flags;
        switch_thread_rwlock_t *rwlock;
        int refs;
        switch_mutex_t *reflock;
        switch_loadable_module_interface_t *parent;
        struct switch_chat_application_interface *next;
};

/*! \brief A module interface to implement an api function */
struct switch_api_interface {
        /*! the name of the interface */
        const char *interface_name;
        /*! a description of the api function */
        const char *desc;
        /*! function the api call uses */
        switch_api_function_t function;
        /*! an example of the api syntax */
        const char *syntax;
        switch_thread_rwlock_t *rwlock;
        int refs;
        switch_mutex_t *reflock;
        switch_loadable_module_interface_t *parent;
        struct switch_api_interface *next;
};


/*! \brief A module interface to implement a json api function */
struct switch_json_api_interface {
        /*! the name of the interface */
        const char *interface_name;
        /*! a description of the api function */
        const char *desc;
        /*! function the api call uses */
        switch_json_api_function_t function;
        /*! an example of the api syntax */
        const char *syntax;
        switch_thread_rwlock_t *rwlock;
        int refs;
        switch_mutex_t *reflock;
        switch_loadable_module_interface_t *parent;
        struct switch_json_api_interface *next;
};

#define PROTECT_INTERFACE(_it) if (_it) {switch_mutex_lock(_it->reflock); switch_thread_rwlock_rdlock(_it->parent->rwlock); switch_thread_rwlock_rdlock(_it->rwlock); _it->refs++; _it->parent->refs++; switch_mutex_unlock(_it->reflock);}     //if (!strcmp(_it->interface_name, "user")) switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_CRIT, "+++++++++++LOCK %s %d/%d\n", _it->interface_name, _it->refs, _it->parent->refs);
#define UNPROTECT_INTERFACE(_it) if (_it) {switch_mutex_lock(_it->reflock); switch_thread_rwlock_unlock(_it->rwlock); switch_thread_rwlock_unlock(_it->parent->rwlock); _it->refs--; _it->parent->refs--; switch_mutex_unlock(_it->reflock);}   //if (!strcmp(_it->interface_name, "user")) switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_CRIT, "---------UNLOCK %s %d/%d\n", _it->interface_name, _it->refs, _it->parent->refs);

#include "switch_frame.h"

struct switch_slin_data {
        switch_core_session_t *session;
        switch_frame_t write_frame;
        switch_codec_t codec;
        char frame_data[SWITCH_RECOMMENDED_BUFFER_SIZE];
};

SWITCH_END_EXTERN_C
#endif
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