diff --git a/src/mod/codecs/mod_skel_codec/mod_skel_codec.c b/src/mod/codecs/mod_skel_codec/mod_skel_codec.c new file mode 100644 index 0000000000..4a8e71db0a --- /dev/null +++ b/src/mod/codecs/mod_skel_codec/mod_skel_codec.c @@ -0,0 +1,222 @@ +/* + * FreeSWITCH Modular Media Switching Software Library / Soft-Switch Application + * Copyright (C) 2005-2009, Anthony Minessale II + * + * 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 / SKEL codec module + * + * The Initial Developer of the Original Code is + * Moises Silva + * Portions created by the Initial Developer are Copyright (C) + * the Initial Developer. All Rights Reserved. + * + * Contributor(s): + * Moises Silva + * + * mod_skel_codec -- FreeSWITCH skeleton codec + * + */ + +/* + * Other source of reference for module building: + * src/mod/applications/mod_skel/mod_skel.c + * http://files.freeswitch.org/cluecon_2009/presentations/Silva_FreeSWITCH_Modules_For_Asterisk_Devs.ppt + * You can load this codec with this command: + * freeswitch@localhost> load mod_skel_codec + * 2009-09-23 12:56:55.616573 [CONSOLE] switch_loadable_module.c:889 Successfully Loaded [mod_skel_codec] + * 2009-09-23 12:56:55.616573 [NOTICE] switch_loadable_module.c:182 Adding Codec 'SKEL' (SKEL 8.0k) 8000hz 20ms + * 2009-09-23 12:56:55.616573 [NOTICE] switch_loadable_module.c:270 Adding API Function 'skel_sayhi' + * + * Then test the API with: + * freeswitch@localhost.localdomain> skel_sayhi + * API CALL [skel_sayhi()] output: + * Hello, I am the skeleton codec and I am not useful for users ... I feel so depressed :-( + * */ +#include + +/* prototype of the module loading function, this function will be called when loading the shared object/DLL into FS core */ +SWITCH_MODULE_LOAD_FUNCTION(mod_skel_codec_load); + +/* Module definition structure, this macro does something like + * static const char modname[] = "mod_skel_codec"; + * switch_loadable_module_function_table_t mod_skel_codec_module_interface = { load, shutdown, runtime, flags }; + * */ +SWITCH_MODULE_DEFINITION(mod_skel_codec, mod_skel_codec_load, NULL, NULL); + +/* Typically you will have a context structure to track your resources */ +struct skel_context { + /* dummy counters to check how many times the encode/decode routines are called */ + int32_t encodes; + int32_t decodes; +}; + +static switch_status_t switch_skel_init(switch_codec_t *codec, switch_codec_flag_t flags, const switch_codec_settings_t *codec_settings) +{ + uint32_t encoding, decoding; + struct skel_context *context = NULL; + switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_DEBUG, "Skel init called.\n"); + + encoding = (flags & SWITCH_CODEC_FLAG_ENCODE); + decoding = (flags & SWITCH_CODEC_FLAG_DECODE); + + if (!(encoding || decoding)) { + return SWITCH_STATUS_FALSE; + } + + /* alloc memory for your internal data structure, no need to free it on destroy, since is allocated from the pool and the core will take care of it */ + if (!(context = switch_core_alloc(codec->memory_pool, sizeof(*context)))) { + return SWITCH_STATUS_FALSE; + } + + codec->private_info = context; + context->encodes = 0; + context->decodes = 0; + + return SWITCH_STATUS_SUCCESS; +} + +/* see src/switch_core_io.c (search switch_core_codec_encode/decode) for more details in expected return codes for the codec interface */ +/* sample return codes, success and error are the typical: + * SWITCH_STATUS_SUCCESS, success + * SWITCH_STATUS_FALSE, error + * SWITCH_STATUS_RESAMPLE, resampling needed + * SWITCH_STATUS_NOOP, NOOP indicates that the audio in is already the same as the audio out, so no conversion was necessary. + * SWITCH_STATUS_NOT_INITALIZED, failure to init, you can use this to init on first usage and no in switch_skel_init? + * */ +static switch_status_t switch_skel_encode(switch_codec_t *codec, + switch_codec_t *other_codec, /* codec that was used by the other side */ + void *decoded_data, /* decoded data that we must encode */ + uint32_t decoded_data_len /* decoded data length */, + uint32_t decoded_rate /* rate of the decoded data */, + void *encoded_data, /* here we will store the encoded data */ + uint32_t *encoded_data_len, /* here we will set the length of the encoded data */ + uint32_t *encoded_rate /* here we will set the rate of the encoded data */, + unsigned int *flag /* frame flag, see switch_frame_flag_enum_t */) +{ + struct skel_context *context = codec->private_info; + /* FS core checks the actual samples per second and microseconds per packet to determine the buffer size in the worst case scenario, no need to check + * whether the buffer passed in by the core (encoded_data) will be big enough */ + switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_DEBUG, "Skel encode called.\n"); + memcpy(encoded_data, decoded_data, decoded_data_len); + *encoded_data_len = decoded_data_len; + *encoded_rate = decoded_rate; + context->encodes++; + return SWITCH_STATUS_SUCCESS; +} + +/* sample return codes, success and error are the typical: + * SWITCH_STATUS_SUCCESS, success + * SWITCH_STATUS_FALSE, error + * SWITCH_STATUS_RESAMPLE, resampling needed + * SWITCH_STATUS_BREAK, do nothing else with the frame but dont report error, seems to be only useful for mod_g729 + * SWITCH_STATUS_NOOP, NOOP indicates that the audio in is already the same as the audio out, so no conversion was necessary. + * SWITCH_STATUS_NOT_INITALIZED, failure to init, you can use this to init on first usage and no in switch_skel_init? + * */ +static switch_status_t switch_skel_decode(switch_codec_t *codec, /* codec session handle */ + switch_codec_t *other_codec, /* what is this? */ + void *encoded_data, /* data that we must decode into slinear and put it in decoded_data */ + uint32_t encoded_data_len, /* length in bytes of the encoded data */ + uint32_t encoded_rate, /* at which rate was the data encoded */ + void *decoded_data, /* buffer where we must put the decoded data */ + uint32_t *decoded_data_len, /* we must set this value to the size of the decoded data */ + uint32_t *decoded_rate, /* rate of the decoded data */ + unsigned int *flag /* frame flag, see switch_frame_flag_enum_t */) +{ + struct skel_context *context = codec->private_info; + /* FS core checks the actual samples per second and microseconds per packet to determine the buffer size in the worst case scenario, no need to check + * whether the buffer passed in by the core will be enough */ + switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_DEBUG, "Skel decode called.\n"); + memcpy(decoded_data, encoded_data, encoded_data_len); + *decoded_data_len = encoded_data_len; + *decoded_rate = encoded_rate; + context->decodes++; + return SWITCH_STATUS_SUCCESS; +} + +static switch_status_t switch_skel_destroy(switch_codec_t *codec) +{ + /* things that you may do here is closing files, sockets or other resources used during the codec session + * no need to free memory allocated from the pool though, the owner of the pool takes care of that */ + struct skel_context *context = codec->private_info; + context->encodes = 0; + context->decodes = 0; /* silly, context was allocated in the pool and therefore will be destroyed soon, exact time is not guaranteed though */ + return SWITCH_STATUS_SUCCESS; +} + +/* A standard API registered by the this codec module, APIs can be executed from CLI, mod_event_socket, or many other interfaces + * any information or actions you want to publish for users on demand is typically exposed through an API */ +SWITCH_STANDARD_API(skel_sayhi) +/* static switch_status_t skel_sayhi(const char *cmd, switch_core_session_t *session, switch_stream_handle_t *stream) */ +{ + stream->write_function(stream, "Hello, I am the skeleton codec and I am not useful for users ... I feel so depressed :-( \n"); + return SWITCH_STATUS_SUCCESS; +} + +/* switch_status_t mod_skel_codec_load(switch_loadable_module_interface_t **module_interface, switch_memory_pool_t *pool) */ +SWITCH_MODULE_LOAD_FUNCTION(mod_skel_codec_load) +{ + /* the codec interface that will be registered with the core */ + switch_codec_interface_t *codec_interface; + + /* the API interface, only needed if you wish to register APIs + * (like commands exposed through CLI, mod_event_socket or any other FS interface capable of executing APIs) */ + switch_api_interface_t *api_interface; + + /* The core gives us a blank module interface pointer and a pool of memory, we allocate memory from that pool to create our module interface + * and set the pointer to that chunk of allocated memory */ + *module_interface = switch_loadable_module_create_module_interface(pool, modname); + + /* SWITCH_ADD_CODEC allocates a codec interface structure from the pool the core gave us and adds it to the internal interface list the core keeps, + * gets a codec id and set the given codec name to it. + * At this point there is an empty shell codec interface registered, but not yet implementations */ + SWITCH_ADD_CODEC(codec_interface, "SKEL 8.0k"); /* 8.0kbit */ + + /* Now add as many codec implementations as needed, typically this is done inside a for loop where the packetization size is + * incremented (10ms, 20ms, 30ms etc) as needed */ + switch_core_codec_add_implementation(pool, + codec_interface, /* the codec interface we allocated and we want to register with the core */ + SWITCH_CODEC_TYPE_AUDIO, /* enumeration defining the type of the codec */ + 0, /* the IANA code number, ie http://www.iana.org/assignments/rtp-parameters */ + "SKEL", /* the IANA code name */ + NULL, /* default fmtp to send (can be overridden by the init function), fmtp is used in SDP for format specific parameters */ + 8000, /* samples transferred per second */ + 8000, /* actual samples transferred per second */ + 8000, /* bits transferred per second */ + 20000, /* for 20ms (milliseconds) frames, 20,000 microseconds and so on, you can register the same codec with different packetization */ + 160, /* number of samples per frame, for this dummy implementation is 160, which is the number of samples in 20ms at 8000 samples per second */ + 320, /* number of bytes per frame decompressed */ + 320, /* number of bytes per frame compressed, since we dont really compress anything, is the same number as per frame decompressed */ + 1, /* number of channels represented */ + 20, /* number of frames per network packet */ + switch_skel_init, /* function to initialize a codec session using this implementation */ + switch_skel_encode, /* function to encode slinear data into encoded data */ + switch_skel_decode, /* function to decode encoded data into slinear data */ + switch_skel_destroy); /* deinitalize a codec handle using this implementation */ + + SWITCH_ADD_API(api_interface, "skel_sayhi", "Skel Codec Says Hi", skel_sayhi, NULL); + switch_console_set_complete("add skel_sayhi"); /* For CLI completion */ + /* indicate that the module should continue to be loaded */ + return SWITCH_STATUS_SUCCESS; +} + +/* For Emacs: + * Local Variables: + * mode:c + * indent-tabs-mode:t + * tab-width:4 + * c-basic-offset:4 + * End: + * For VIM: + * vim:set softtabstop=4 shiftwidth=4 tabstop=4: + */