Group PJLIB_UTIL_CLI

group PJLIB_UTIL_CLI

A CLI framework features an interface for defining command specification, parsing, and executing a command. It also features an interface to communicate with various front-ends, such as console, telnet. Application normally needs only one CLI instance to be created. On special cases, application could also create multiple CLI instances, with each instance has specific command structure.

| vid help                  Show this help screen                             |
| vid enable|disable        Enable or disable video in next offer/answer      |
| vid call add              Add video stream for current call                 |
| vid call cap N ID         Set capture dev ID for stream #N in current call  |
| disable_codec g711|g722   Show this help screen                             |
<CMD name='vid' id='0' desc="">
       <CMD name='help' id='0' desc='' />
       <CMD name='enable' id='0' desc='' />
       <CMD name='disable' id='0' desc='' />
       <CMD name='call' id='0' desc='' >
                <CMD name='add' id='101' desc='...' />
                <CMD name='cap' id='102' desc='...' >
                   <ARG name='streamno' type='int' desc='...' id='1'/>
                   <ARG name='devid' type='int' optional='1' id='2'/>
                </CMD>
       </CMD>
</CMD>
<CMD name='disable_codec' id=0 desc="">
        <ARG name='codec_list' type='choice' id='3'>
            <CHOICE value='g711'/>
            <CHOICE value='g722'/>
        </ARG>
</CMD>

Typedefs

typedef struct pj_cli_t pj_cli_t

This opaque structure represents a CLI application. A CLI application is the root placeholder of other CLI objects. In an application, one (and normally only one) CLI application instance needs to be created.

typedef int pj_cli_cmd_id

Type of command id.

typedef int pj_cli_arg_id

Type of argument id.

typedef struct pj_cli_cmd_spec pj_cli_cmd_spec

Forward declaration of pj_cli_cmd_spec structure.

typedef struct pj_cli_arg_spec pj_cli_arg_spec

Forward declaration for CLI argument spec structure.

typedef void (*pj_cli_get_dyn_choice)(pj_cli_dyn_choice_param *param)

This specifies the callback type for argument handlers, which will be called to get the valid values of the choice type arguments.

typedef pj_status_t (*pj_cli_cmd_handler)(pj_cli_cmd_val *cval)

This specifies the callback type for command handlers, which will be executed when the specified command is invoked.

Param cval:

The command that is specified by the user.

Return:

Return the status of the command execution.

Functions

void pj_cli_write_log(pj_cli_t *cli, int level, const char *buffer, int len)

Write a log message to the CLI application. The CLI application will send the log message to all the registered front-ends.

Parameters:

  • cli – The CLI application instance.

  • level – Verbosity level of this message message.

  • buffer – The message itself.

  • len – Length of this message.

pj_status_t pj_cli_create(pj_cli_cfg *cfg, pj_cli_t **p_cli)

Create a new CLI application instance.

Parameters:

  • cfg – CLI application creation parameters.

  • p_cli – Pointer to receive the returned instance.

Returns:

PJ_SUCCESS on success, or the appropriate error code.

pj_cli_cmd_id pj_cli_get_cmd_id(const pj_cli_cmd_spec *cmd)

This specifies the function to get the id of the specified command

Parameters:

cmd – The specified command.

Returns:

The command id

pj_cli_cfg *pj_cli_get_param(pj_cli_t *cli)

Get the internal parameter of the CLI instance.

Parameters:

cli – The CLI application instance.

Returns:

CLI parameter instance.

void pj_cli_quit(pj_cli_t *cli, pj_cli_sess *req, pj_bool_t restart)

Call this to signal application shutdown. Typically application would call this from it’s “Quit” menu or similar command to quit the application.

See also pj_cli_sess_end_session() to end a session instead of quitting the whole application.

Parameters:

  • cli – The CLI application instance.

  • req – The session on which the shutdown request is received.

  • restart – Indicate whether application restart is wanted.

pj_bool_t pj_cli_is_quitting(pj_cli_t *cli)

Check if application shutdown or restart has been requested.

Parameters:

cli – The CLI application instance.

Returns:

PJ_TRUE if pj_cli_quit() has been called.

pj_bool_t pj_cli_is_restarting(pj_cli_t *cli)

Check if application restart has been requested.

Parameters:

cli – The CLI application instance.

Returns:

PJ_TRUE if pj_cli_quit() has been called with restart parameter set.

void pj_cli_destroy(pj_cli_t *cli)

Destroy a CLI application instance. This would also close all sessions currently running for this CLI application.

Parameters:

cli – The CLI application.

void pj_cli_cfg_default(pj_cli_cfg *param)

Initialize a pj_cli_cfg with its default values.

Parameters:

param – The instance to be initialized.

void pj_cli_register_front_end(pj_cli_t *cli, pj_cli_front_end *fe)

Register a front end to the CLI application.

Parameters:

  • cli – The CLI application.

  • fe – The CLI front end to be registered.

pj_status_t pj_cli_add_cmd_from_xml(pj_cli_t *cli, pj_cli_cmd_spec *group, const pj_str_t *xml, pj_cli_cmd_handler handler, pj_cli_cmd_spec **p_cmd, pj_cli_get_dyn_choice get_choice)

Create a new complete command specification from an XML node text and register it to the CLI application.

Note that the input string MUST be NULL terminated.

Parameters:

  • cli – The CLI application.

  • group – Optional group to which this command will be added to, or specify NULL if this command is a root command.

  • xml – Input string containing XML node text for the command, MUST be NULL terminated.

  • handler – Function handler for the command. This must be NULL if the command specifies a command group.

  • p_cmd – Optional pointer to store the newly created specification.

  • get_choice – Function handler for the argument. Specify this for dynamic choice type arguments.

Returns:

PJ_SUCCESS on success, or the appropriate error code.

void pj_cli_exec_info_default(pj_cli_exec_info *param)

Initialize pj_cli_exec_info with its default values.

Parameters:

param – The param to be initialized.

void pj_cli_sess_write_msg(pj_cli_sess *sess, const char *buffer, pj_size_t len)

Write a log message to the specific CLI session.

Parameters:

  • sess – The CLI active session.

  • buffer – The message itself.

  • len – Length of this message.

pj_status_t pj_cli_sess_parse(pj_cli_sess *sess, char *cmdline, pj_cli_cmd_val *val, pj_pool_t *pool, pj_cli_exec_info *info)

Parse an input cmdline string. The first word of the command line is the command itself, which will be matched against command specifications registered in the CLI application.

Zero or more arguments follow the command name. Arguments are separated by one or more whitespaces. Argument may be placed inside a pair of quotes, double quotes, ‘{’ and ‘}’, or ‘[’ and ‘]’ pairs. This is useful when the argument itself contains whitespaces or other restricted characters. If the quote character itself is to appear in the argument, the argument then must be quoted with different quote characters. There is no character escaping facility provided by this function (such as the use of backslash ‘' character).

The cmdline may be followed by an extra newline (LF or CR-LF characters), which will be removed by the function. However any more characters following this newline will cause an error to be returned.

Parameters:

  • sess – The CLI session.

  • cmdline – The command line string to be parsed.

  • val – Structure to store the parsing result.

  • pool – The pool to allocate memory from.

  • info – Additional info to be returned regarding the parsing.

Returns:

This function returns the status of the parsing, which can be one of the following :

  • PJ_SUCCESS: a command was executed successfully.

  • PJ_EINVAL: invalid parameter to this function.

  • PJ_ENOTFOUND: command is not found.

  • PJ_CLI_EAMBIGUOUS: command/argument is ambiguous.

  • PJ_CLI_EMISSINGARG: missing argument.

  • PJ_CLI_EINVARG: invalid command argument.

  • PJ_CLI_EEXIT: “exit” has been called to end the current session. This is a signal for the application to end it’s main loop.

void pj_cli_sess_end_session(pj_cli_sess *sess)

End the specified session, and destroy it to release all resources used by the session.

See also pj_cli_sess and pj_cli_front_end for more info regarding the creation process. See also pj_cli_quit() to quit the whole application instead.

Parameters:

sess – The CLI session to be destroyed.

pj_status_t pj_cli_sess_exec(pj_cli_sess *sess, char *cmdline, pj_pool_t *pool, pj_cli_exec_info *info)

Execute a command line. This function will parse the input string to find the appropriate command and verify whether the string matches the command specifications. If matches, the command will be executed, and the return value of the command will be set in the cmd_ret field of the info argument, if specified.

See also pj_cli_sess_parse() for more info regarding the cmdline format.

Parameters:

  • sess – The CLI session.

  • cmdline – The command line string to be executed.

  • pool – The pool to allocate memory from.

  • info – Optional pointer to receive additional information related to the execution of the command (such as the command return value).

Returns:

This function returns the status of the command parsing and execution (note that the return value of the handler itself will be returned in info argument, if specified). Please see the return value of pj_cli_sess_parse() for possible return values.

struct pj_cli_cfg
#include <cli.h>

This describes the parameters to be specified when creating a CLI application with pj_cli_create(). Application MUST initialize this structure by calling pj_cli_cfg_default() before using it.

Public Members

pj_str_t name

The application name, which will be used in places such as logs. This field is mandatory.

pj_str_t title

Optional application title, which will be used in places such as window title. If not specified, the application name will be used as the title.

pj_pool_factory *pf

The pool factory where all memory allocations will be taken from. This field is mandatory.

struct pj_cli_cmd_val
#include <cli.h>

This structure contains the command to be executed by command handler.

Public Members

pj_cli_sess *sess

The session on which the command was executed on.

const pj_cli_cmd_spec *cmd

The command specification being executed.

int argc

Number of argvs.

pj_str_t argv[PJ_CLI_MAX_ARGS]

Array of args, with argv[0] specifies the name of the cmd.

struct pj_cli_hint_info
#include <cli.h>

This structure contains the hints information for the end user. This structure could contain either command or argument information. The front-end will format the information and present it to the user.

Public Members

pj_str_t name

The hint value.

pj_str_t type

The hint type.

pj_str_t desc

Helpful description of the hint value.

struct pj_cli_exec_info
#include <cli.h>

This structure contains extra information returned by pj_cli_sess_exec()/ pj_cli_sess_parse(). Upon return from the function, various other fields in this structure will be set by the function.

Public Members

int err_pos

If command parsing failed, on return this will point to the location where the failure occurs, otherwise the value will be set to -1.

pj_cli_cmd_id cmd_id

If a command matching the command in the cmdline was found, on return this will be set to the command id of the command, otherwise it will be set to PJ_CLI_INVALID_CMD_ID.

pj_status_t cmd_ret

If a command was executed, on return this will be set to the return value of the command, otherwise it will contain PJ_SUCCESS.

unsigned hint_cnt

The number of hint elements

pj_cli_hint_info hint[PJ_CLI_MAX_HINTS]

If pj_cli_sess_parse() fails because of a missing argument or ambigous command/argument, the function returned PJ_CLI_EMISSINGARG or PJ_CLI_EAMBIGUOUS error. This field will contain the hint information. This is useful to give helpful information to the end_user.

struct pj_cli_arg_choice_val
#include <cli.h>

This structure contains the information returned from the dynamic argument callback.

Public Members

pj_str_t value

The argument choice value

pj_str_t desc

Helpful description of the choice value. This text will be used when displaying the help texts for the choice value

struct pj_cli_dyn_choice_param
#include <cli.h>

This structure contains the parameters for pj_cli_get_dyn_choice

Public Members

pj_cli_sess *sess

The session on which the command was executed on.

pj_cli_cmd_spec *cmd

The command being processed.

pj_cli_arg_id arg_id

The argument id.

unsigned max_cnt

The maximum number of values that the choice can hold.

pj_pool_t *pool

The pool to allocate memory from.

unsigned cnt

The choice values count.

pj_cli_arg_choice_val choice[PJ_CLI_MAX_CHOICE_VAL]

Array containing the valid choice values.