PJSUA-API Basic API
[PJSUA API - High Level Softphone API for C/C++ and Python]

Detailed Description

The base PJSUA API controls PJSUA creation, initialization, and startup, and also provides various auxiliary functions.

Before anything else, application must create PJSUA by calling pjsua_create() (or py_pjsua.create() from Python). This, among other things, will initialize PJLIB, which is crucial before any PJLIB functions can be called, PJLIB-UTIL, and create a SIP endpoint.

After this function is called, application can create a memory pool (with pjsua_pool_create()) and read configurations from command line or file to build the settings to initialize PJSUA below.

Initializing PJSUA

After PJSUA is created, application can initialize PJSUA by calling pjsua_init(). This function takes several optional configuration settings in the argument, if application wants to set them.

PJSUA-LIB Initialization (in C)

Sample code to initialize PJSUA in C code:

 #include <pjsua-lib/pjsua.h>

 #define THIS_FILE  __FILE__

 static pj_status_t app_init(void)
 {
    pjsua_config         ua_cfg;
    pjsua_logging_config log_cfg;
    pjsua_media_config   media_cfg;
    pj_status_t status;

    // Must create pjsua before anything else!
    status = pjsua_create();
    if (status != PJ_SUCCESS) {
        pjsua_perror(THIS_FILE, "Error initializing pjsua", status);
        return status;
    }

    // Initialize configs with default settings.
    pjsua_config_default(&ua_cfg);
    pjsua_logging_config_default(&log_cfg);
    pjsua_media_config_default(&media_cfg);

    // At the very least, application would want to override
    // the call callbacks in pjsua_config:
    ua_cfg.cb.on_incoming_call = ...
    ua_cfg.cb.on_call_state = ..
    ...

    // Customize other settings (or initialize them from application specific
    // configuration file):
    ...

    // Initialize pjsua
    status = pjsua_init(&ua_cfg, &log_cfg, &media_cfg);
    if (status != PJ_SUCCESS) {
          pjsua_perror(THIS_FILE, "Error initializing pjsua", status);
          return status;
    }
    .
    ...
 }

PJSUA-LIB Initialization (in Python)

Sample code to initialize PJSUA in Python code:

import py_pjsua

#
# Initialize pjsua.
#
def app_init():
        # Create pjsua before anything else
        status = py_pjsua.create()
        if status != 0:
                err_exit("pjsua create() error", status)

        # We use default logging config for this sample
        log_cfg = py_pjsua.logging_config_default()

        # Create and initialize pjsua config
        # Note: for this Python module, thread_cnt must be 0 since Python
        #       doesn't like to be called from alien thread (pjsua's thread
        #       in this case)       
        ua_cfg = py_pjsua.config_default()
        ua_cfg.thread_cnt = 0
        ua_cfg.user_agent = "PJSUA/Python 0.1"

        # Override callbacks. At the very least application would want to
        # override the call callbacks in pjsua_config
        ua_cfg.cb.on_incoming_call = ...
        ua_cfg.cb.on_call_state = ...

        # Use default media config for this cample
        med_cfg = py_pjsua.media_config_default()

        #
        # Initialize pjsua!!
        #
        status = py_pjsua.init(ua_cfg, log_cfg, med_cfg)
        if status != 0:
                err_exit("pjsua init() error", status)



# Utility: display PJ error and exit
#
def err_exit(title, rc):
        py_pjsua.perror(THIS_FILE, title, rc)
        exit(1)

Other Initialization

After PJSUA is initialized with pjsua_init(), application will normally need/want to perform the following tasks:

create SIP transport with pjsua_transport_create(). Application would to call pjsua_transport_create() for each transport types that it wants to support (for example, UDP, TCP, and TLS). Please see PJSUA-API Signaling Transport section for more info.
create one or more SIP accounts with pjsua_acc_add() or pjsua_acc_add_local(). The SIP account is used for registering with the SIP server, if any. Please see PJSUA-API Accounts Management for more info.
add one or more buddies with pjsua_buddy_add(). Please see PJSUA-API Buddy, Presence, and Instant Messaging section for more info.
optionally configure the sound device, codec settings, and other media settings. Please see PJSUA-API Media Manipulation for more info.

Starting PJSUA

After all initializations have been done, application must call pjsua_start() to start PJSUA. This function will check that all settings have been properly configured, and apply default settings when they haven't, or report error status when it is unable to recover from missing settings.

Most settings can be changed during run-time. For example, application may add, modify, or delete accounts, buddies, or change media settings during run-time.

C Example for Starting PJSUA

Sample code:

 static pj_status_t app_run(void)
 {
    pj_status_t status;

    // Start pjsua
    status = pjsua_start();
    if (status != PJ_SUCCESS) {
        pjsua_destroy();
        pjsua_perror(THIS_FILE, "Error starting pjsua", status);
        return status;
    }

    // Run application loop
    while (1) {
        char choice[10];
        
        printf("Select menu: ");
        fgets(choice, sizeof(choice), stdin);
        ...
    }
 }

Python Example for starting PJSUA

For Python, starting PJSUA-LIB takes one more step, that is to initialize Python worker thread to poll PJSUA-LIB. This step is necessary because Python doesn't like it when it is called by an "alien" thread (that is, thread that is not created using Python API).

Because of this, we cannot use a worker thread in PJSUA-LIB, because then the Python callback will be called by an "alien" thread and this would crash Python (or raise assert() probably).

So because worker thread is disabled, we need to create a worker thread in Python. Note that this may not be necessary if we're creating a GUI application, because then we can attach, for example, a GUI timer object to poll the PJSUA-LIB. But because we're creating a console application which will block at sys.stdin.readline(), we need to have a worker thread to poll PJSUA-LIB.

import thread

C_QUIT = 0


def app_start():
        # Done with initialization, start pjsua!!
        #
        status = py_pjsua.start()
        if status != 0:
                py_pjsua.destroy()
                err_exit("Error starting pjsua!", status)

        # Start worker thread
        thr = thread.start_new(worker_thread_main, (0,))
    
        print "PJSUA Started!!"

#
# Worker thread function.
# Python doesn't like it when it's called from an alien thread
# (pjsua's worker thread, in this case), so for Python we must
# disable worker thread in pjsua and poll pjsua from Python instead.
#
def worker_thread_main(arg):
        global C_QUIT
        thread_desc = 0
        status = py_pjsua.thread_register("python worker", thread_desc)
        if status != 0:
                py_pjsua.perror(THIS_FILE, "Error registering thread", status)
        else:
                while C_QUIT == 0:
                        py_pjsua.handle_events(50)
                print "Worker thread quitting.."
                C_QUIT = 2

Define Documentation

#define PJSUA_INVALID_ID (-1)

Constant to identify invalid ID for all sorts of IDs.

#define PJSUA_ACC_MAX_PROXIES 8

Maximum proxies in account.

#define PJSUA_DEFAULT_USE_SRTP PJMEDIA_SRTP_DISABLED

Default value of SRTP mode usage. Valid values are PJMEDIA_SRTP_DISABLED, PJMEDIA_SRTP_OPTIONAL, and PJMEDIA_SRTP_MANDATORY.

#define PJSUA_DEFAULT_SRTP_SECURE_SIGNALING 1

Default value of secure signaling requirement for SRTP. Valid values are: 0: SRTP does not require secure signaling 1: SRTP requires secure transport such as TLS 2: SRTP requires secure end-to-end transport (SIPS)

#define pjsip_cred_dup pjsip_cred_info_dup

The implementation has been moved to sip_auth.h

Typedef Documentation

typedef int pjsua_call_id

Call identification

typedef int pjsua_acc_id

Account identification

typedef int pjsua_buddy_id

Buddy identification

typedef int pjsua_player_id

File player identification

typedef int pjsua_recorder_id

File recorder identification

typedef int pjsua_conf_port_id

Conference port identification

typedef struct pjsua_media_config pjsua_media_config

Forward declaration

Function Documentation

void pjsua_logging_config_default ( pjsua_logging_config * cfg )

Use this function to initialize logging config.

Parameters:

cfg

The logging config to be initialized.

Python Syntax:

The Python function instantiates and initialize the logging config:

 logging_cfg = py_pjsua.logging_config_default()

void pjsua_logging_config_dup	(	pj_pool_t *	pool,
		pjsua_logging_config *	dst,
		const pjsua_logging_config *	src
	)

Use this function to duplicate logging config.

Parameters:

	pool	Pool to use.
	dst	Destination config.
	src	Source config.

Python Syntax:: Not available (for now). Ideally we should be able to just assign one config to another, but this has not been tested.

void pjsua_config_default ( pjsua_config * cfg )

Use this function to initialize pjsua config.

Parameters:

cfg

pjsua config to be initialized.

Python Sample Syntax:

The corresponding Python function creates an instance of the config and initializes it to the default settings:

    cfg = py_pjsua.config_default()

void pjsua_config_dup	(	pj_pool_t *	pool,
		pjsua_config *	dst,
		const pjsua_config *	src
	)

Duplicate pjsua_config.

Parameters:

	pool	The pool to get memory from.
	dst	Destination config.
	src	Source config.

void pjsua_msg_data_init ( pjsua_msg_data * msg_data )

Initialize message data.

Parameters:

msg_data

Message data to be initialized.

Python

The corresponding Python function creates and initializes the structure:

    msg_data = py_pjsua.msg_data_init()

pj_status_t pjsua_create ( void )

Instantiate pjsua application. Application must call this function before calling any other functions, to make sure that the underlying libraries are properly initialized. Once this function has returned success, application must call pjsua_destroy() before quitting.

Returns:: PJ_SUCCESS on success, or the appropriate error code.

Python:

    status = py_pjsua.create()

pj_status_t pjsua_init	(	const pjsua_config *	ua_cfg,
		const pjsua_logging_config *	log_cfg,
		const pjsua_media_config *	media_cfg
	)

Initialize pjsua with the specified settings. All the settings are optional, and the default values will be used when the config is not specified.

Note that pjsua_create() MUST be called before calling this function.

Parameters:

	ua_cfg	User agent configuration.
	log_cfg	Optional logging configuration.
	media_cfg	Optional media configuration.

Returns:: PJ_SUCCESS on success, or the appropriate error code.

Python:

The function is similar in Python:

    status = py_pjsua.init(ua_cfg, log_cfg, media_cfg)

Note that ua_cfg, log_cfg, and media_cfg are optional, and the Python script may pass None if it doesn't want to configure the setting.

pj_status_t pjsua_start ( void )

Application is recommended to call this function after all initialization is done, so that the library can do additional checking set up additional

Application may call this function anytime after pjsua_init().

Returns:: PJ_SUCCESS on success, or the appropriate error code.

Python:

The function is similar in Python:

    status = py_pjsua.start()

pj_status_t pjsua_destroy ( void )

Destroy pjsua. Application is recommended to perform graceful shutdown before calling this function (such as unregister the account from the SIP server, terminate presense subscription, and hangup active calls), however, this function will do all of these if it finds there are active sessions that need to be terminated. This function will approximately block for one second to wait for replies from remote.

Application.may safely call this function more than once if it doesn't keep track of it's state.

Returns:: PJ_SUCCESS on success, or the appropriate error code.

Python:

The function is similar in Python:

    status = py_pjsua.destroy()

int pjsua_handle_events ( unsigned msec_timeout )

Poll pjsua for events, and if necessary block the caller thread for the specified maximum interval (in miliseconds).

Application doesn't normally need to call this function if it has configured worker thread (thread_cnt field) in pjsua_config structure, because polling then will be done by these worker threads instead.

Parameters:

msec_timeout

Maximum time to wait, in miliseconds.

Returns:: The number of events that have been handled during the poll. Negative value indicates error, and application can retrieve the error as (status = -return_value).

Python:

The function is similar in Python:

    n = py_pjsua.handle_events(msec_timeout)

pj_pool_t* pjsua_pool_create	(	const char *	name,
		pj_size_t	init_size,
		pj_size_t	increment
	)

Create memory pool to be used by the application. Once application finished using the pool, it must be released with pj_pool_release().

Parameters:

	name	Optional pool name.
	init_size	Initial size of the pool.
	increment	Increment size.

Returns:: The pool, or NULL when there's no memory.

Python:

Python script may also create a pool object from the script:

    pool = py_pjsua.pool_create(name, init_size, increment)

pj_status_t pjsua_reconfigure_logging ( const pjsua_logging_config * c )

Application can call this function at any time (after pjsua_create(), of course) to change logging settings.

Parameters:

Logging configuration.

Returns:: PJ_SUCCESS on success, or the appropriate error code.

Python:

The function is similar in Python:

    status = py_pjsua.reconfigure_logging(log_cfg)

pjsip_endpoint* pjsua_get_pjsip_endpt ( void )

Internal function to get SIP endpoint instance of pjsua, which is needed for example to register module, create transports, etc. Only valid after pjsua_init() is called.

Returns:: SIP endpoint instance.

Python:

Application may retrieve the SIP endpoint instance:

    endpt = py_pjsua.get_pjsip_endpt()

However currently the object is just an opaque object and does not have any use for Python scripts.

pjmedia_endpt* pjsua_get_pjmedia_endpt ( void )

Internal function to get media endpoint instance. Only valid after pjsua_init() is called.

Returns:: Media endpoint instance.

Python:

Application may retrieve the media endpoint instance:

    endpt = py_pjsua.get_pjmedia_endpt()

However currently the object is just an opaque object and does not have any use for Python scripts.

pj_pool_factory* pjsua_get_pool_factory ( void )

Internal function to get PJSUA pool factory. Only valid after pjsua_create() is called.

Returns:: Pool factory currently used by PJSUA.

Python:

Application may retrieve the pool factory instance:

    endpt = py_pjsua.get_pool_factory()

However currently the object is just an opaque object and does not have any use for Python scripts.

pj_status_t pjsua_detect_nat_type ( void )

This is a utility function to detect NAT type in front of this endpoint. Once invoked successfully, this function will complete asynchronously and report the result in on_nat_detect() callback of pjsua_callback.

After NAT has been detected and the callback is called, application can get the detected NAT type by calling pjsua_get_nat_type(). Application can also perform NAT detection by calling pjsua_detect_nat_type() again at later time.

Note that STUN must be enabled to run this function successfully.

Returns:: PJ_SUCCESS on success, or the appropriate error code.

pj_status_t pjsua_get_nat_type ( pj_stun_nat_type * type )

Get the NAT type as detected by pjsua_detect_nat_type() function. This function will only return useful NAT type after pjsua_detect_nat_type() has completed successfully and on_nat_detect() callback has been called.

Parameters:

type

NAT type.

Returns:: When detection is in progress, this function will return PJ_EPENDING and type will be set to PJ_STUN_NAT_TYPE_UNKNOWN. After NAT type has been detected successfully, this function will return PJ_SUCCESS and type will be set to the correct value. Other return values indicate error and type will be set to PJ_STUN_NAT_TYPE_ERR_UNKNOWN.

See also:: pjsua_call_get_rem_nat_type()

pj_status_t pjsua_verify_sip_url ( const char * url )

This is a utility function to verify that valid SIP url is given. If the URL is valid, PJ_SUCCESS will be returned.

Parameters:

url

The URL, as NULL terminated string.

Returns:: PJ_SUCCESS on success, or the appropriate error code.

Python:

    status = py_pjsua.verify_sip_url(url)

void pjsua_perror	(	const char *	sender,
		const char *	title,
		pj_status_t	status
	)

This is a utility function to display error message for the specified error code. The error message will be sent to the log.

Parameters:

	sender	The log sender field.
	title	Message title for the error.
	status	Status code.

Python:

    py_pjsua.perror(sender, title, status)

void pjsua_dump ( pj_bool_t detail )

This is a utility function to dump the stack states to log, using verbosity level 3.

Parameters:

detail

Will print detailed output (such as list of SIP transactions) when non-zero.

PJSUA-API Basic API
[PJSUA API - High Level Softphone API for C/C++ and Python]

Detailed Description

Using PJSUA Library

Creating PJSUA

Initializing PJSUA

PJSUA-LIB Initialization (in C)

PJSUA-LIB Initialization (in Python)

Other Initialization

Starting PJSUA

C Example for Starting PJSUA

Python Example for starting PJSUA

Data Structures

Defines

Typedefs

Functions

Define Documentation

Typedef Documentation

Function Documentation

PJSUA-API Basic API [PJSUA API - High Level Softphone API for C/C++ and Python]

Detailed Description

Data Structures

Defines

Typedefs

Functions

Define Documentation

Typedef Documentation

Function Documentation

PJSUA-API Basic API
[PJSUA API - High Level Softphone API for C/C++ and Python]