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diff --git a/docs/reference-v3/func-api.md b/docs/reference-v3/func-api.md new file mode 100644 index 00000000..0ba141df --- /dev/null +++ b/docs/reference-v3/func-api.md @@ -0,0 +1,937 @@ +Functions of class **afb_api** +============================ + +## General functions + +### afb_api_name + +```C +/** + * Get the name of the 'api'. + * + * @param api the api whose name is to be returned + * + * @return the name of the api. + * + * The returned value must not be changed nor freed. + */ +const char *afb_api_name( + afb_api_t api); +``` + +### afb_api_get_userdata + +```C +/** + * Get the "userdata" pointer of the 'api' + * + * @param api the api whose user's data is to be returned + * + * @return the user's data pointer of the api. + * + * @see afb_api_set_userdata + */ +void *afb_api_get_userdata( + afb_api_t api); +``` + +### afb_api_set_userdata + +```C +/** + * Set the "userdata" pointer of the 'api' to 'value' + * + * @param api the api whose user's data is to be set + * @param value the data to set + * + * @see afb_api_get_userdata + */ +void afb_api_set_userdata( + afb_api_t api, + void *value); +``` + +### afb_api_require_api + +```C +/** + * Check that it requires the API of 'name'. + * If 'initialized' is not zero it request the API to be + * initialized, implying its initialization if needed. + * + * Calling this function is only allowed within init. + * + * A single request allows to require multiple apis. + * + * @param api the api that requires the other api by its name + * @param name a space separated list of required api names + * @param initialized if zero, the api is just required to exist. If not zero, + * the api is required to exist and to be initialized at return of the call + * (initializing it if needed and possible as a side effect of the call). + * + * @return 0 in case of success or -1 in case of error with errno set appropriately. + */ +int afb_api_require_api( + afb_api_t api, + const char *name, + int initialized); +``` + + +## Verbosity functions + +### afb_api_wants_log_level + +```C +/** + * Is the log message of 'level (as defined for syslog) required for the api? + * + * @param api the api to check + * @param level the level to check as defined for syslog: + * + * EMERGENCY 0 System is unusable + * ALERT 1 Action must be taken immediately + * CRITICAL 2 Critical conditions + * ERROR 3 Error conditions + * WARNING 4 Warning conditions + * NOTICE 5 Normal but significant condition + * INFO 6 Informational + * DEBUG 7 Debug-level messages + * + * @return 0 if not required or a value not null if required + * + * @see syslog + */ +int afb_api_wants_log_level( + afb_api_t api, + int level); +``` + +### afb_api_vverbose + +```C +/** + * Send to the journal with the logging 'level' a message described + * by 'fmt' applied to the va-list 'args'. + * + * 'file', 'line' and 'func' are indicators of code position in source files + * (see macros __FILE__, __LINE__ and __func__). + * + * 'level' is defined by syslog standard: + * + * EMERGENCY 0 System is unusable + * ALERT 1 Action must be taken immediately + * CRITICAL 2 Critical conditions + * ERROR 3 Error conditions + * WARNING 4 Warning conditions + * NOTICE 5 Normal but significant condition + * INFO 6 Informational + * DEBUG 7 Debug-level messages + * + * @param api the api that collects the logging message + * @param level the level of the message + * @param file the source file that logs the messages or NULL + * @param line the line in the source file that logs the message + * @param func the name of the function in the source file that logs + * @param fmt the format of the message as in printf + * @param args the arguments to the format string of the message as a va_list + * + * @see syslog + * @see printf + */ +void afb_api_vverbose( + afb_api_t api, + int level, + const char *file, + int line, + const char *func, + const char *fmt, + va_list args); +``` + +### afb_api_verbose + +```C +/** + * Send to the journal with the log 'level' a message described + * by 'fmt' and following parameters. + * + * 'file', 'line' and 'func' are indicators of position of the code in source files + * (see macros __FILE__, __LINE__ and __func__). + * + * 'level' is defined by syslog standard: + * EMERGENCY 0 System is unusable + * ALERT 1 Action must be taken immediately + * CRITICAL 2 Critical conditions + * ERROR 3 Error conditions + * WARNING 4 Warning conditions + * NOTICE 5 Normal but significant condition + * INFO 6 Informational + * DEBUG 7 Debug-level messages + * + * @param api the api that collects the logging message + * @param level the level of the message + * @param file the source file that logs the messages or NULL + * @param line the line in the source file that logs the message + * @param func the name of the function in the source file that logs + * @param fmt the format of the message as in printf + * @param ... the arguments to the format string of the message + * + * @see syslog + * @see printf + */ +void afb_api_verbose( + afb_api_t api, + int level, + const char *file, + int line, + const char *func, + const char *fmt, + ...); +``` + +## Data retrieval functions + +### afb_api_rootdir_get_fd + +```C +/** + * Get the root directory file descriptor. This file descriptor can + * be used with functions 'openat', 'fstatat', ... + * + * CAUTION, manipulate this this descriptor with care, in particular, don't close + * it. + * + * This can be used to get the path of the root directory using: + * + * char buffer[MAX_PATH], proc[100]; + * int dirfd = afb_api_rootdir_get_fd(api); + * snprintf(proc, sizeof proc, "/proc/self/fd/%d", dirfd); + * readlink(proc, buffer, sizeof buffer); + * + * But note that within AGL this is the value given by the environment variable + * AFM_APP_INSTALL_DIR. + * + * @param api the api that uses the directory file descriptor + * + * @return the file descriptor of the root directory. + * + * @see afb_api_rootdir_open_locale + */ +int afb_api_rootdir_get_fd( + afb_api_t api); +``` + +### afb_api_rootdir_open_locale + +```C +/** + * Opens 'filename' within the root directory with 'flags' (see function openat) + * using the 'locale' definition (example: "jp,en-US") that can be NULL. + * + * The filename must be relative to the root of the bindings. + * + * The opening mode must be for read or write but not for O_CREAT. + * + * The definition of locales and of how files are searched can be checked + * here: https://www.w3.org/TR/widgets/#folder-based-localization + * and https://tools.ietf.org/html/rfc7231#section-5.3.5 + * + * @param api the api that queries the file + * @param filename the relative path to the file to open + * @param flags the flags for opening as for C function 'open' + * @param locale string indicating how to search content, can be NULL + * + * @return the file descriptor or -1 in case of error and errno is set with the + * error indication. + * + * @see open + * @see afb_api_rootdir_get_fd + */ +int afb_api_rootdir_open_locale( + afb_api_t api, + const char *filename, + int flags, + const char *locale); +``` + +## Calls and job functions + +### afb_api_call + +```C +/** + * Calls the 'verb' of the 'api' with the arguments 'args' and 'verb' in the name of the binding. + * The result of the call is delivered to the 'callback' function with the 'callback_closure'. + * + * For convenience, the function calls 'json_object_put' for 'args'. + * Thus, in the case where 'args' should remain available after + * the function returns, the function 'json_object_get' shall be used. + * + * The 'callback' receives 5 arguments: + * 1. 'closure' the user defined closure pointer 'closure', + * 2. 'object' a JSON object returned (can be NULL) + * 3. 'error' a string not NULL in case of error but NULL on success + * 4. 'info' a string handling some info (can be NULL) + * 5. 'api' the api + * + * @param api The api that makes the call + * @param apiname The api name of the method to call + * @param verb The verb name of the method to call + * @param args The arguments to pass to the method + * @param callback The to call on completion + * @param closure The closure to pass to the callback + * + * + * @see afb_req_subcall + * @see afb_req_subcall_sync + * @see afb_api_call_sync + */ +void afb_api_call( + afb_api_t api, + const char *apiname, + const char *verb, + struct json_object *args, + void (*callback)( + void *closure, + struct json_object *object, + const char *error, + const char * info, + afb_api_t api), + void *closure); +``` + +### afb_api_call_sync + +```C +/** + * Calls the 'verb' of the 'api' with the arguments 'args' and 'verb' in the name of the binding. + * 'result' will receive the response. + * + * For convenience, the function calls 'json_object_put' for 'args'. + * Thus, in the case where 'args' should remain available after + * the function returns, the function 'json_object_get' shall be used. + * + * @param api The api that makes the call + * @param apiname The api name of the method to call + * @param verb The verb name of the method to call + * @param args The arguments to pass to the method + * @param object Where to store the returned object - should call json_object_put on it - can be NULL + * @param error Where to store the copied returned error - should call free on it - can be NULL + * @param info Where to store the copied returned info - should call free on it - can be NULL + * + * @returns 0 in case of success or a negative value in case of error. + * + * @see afb_req_subcall + * @see afb_req_subcall_sync + * @see afb_api_call + */ +int afb_api_call_sync( + afb_api_t api, + const char *apiname, + const char *verb, + struct json_object *args, + struct json_object **object, + char **error, + char **info); +``` + +### afb_api_queue_job + +```C +/** + * Queue the job defined by 'callback' and 'argument' for being executed asynchronously + * in this thread (later) or in an other thread. + * + * If 'group' is not NULL, the jobs queued with a same value (as the pointer value 'group') + * are executed in sequence in the order of there submission. + * + * If 'timeout' is not 0, it represent the maximum execution time for the job in seconds. + * At first, the job is called with 0 as signum and the given argument. + * + * The job is executed with the monitoring of its time and some signals like SIGSEGV and + * SIGFPE. When a such signal is catched, the job is terminated and reexecuted but with + * signum being the signal number (SIGALRM when timeout expired). + * + * When executed, the callback function receives 2 arguments: + * + * - int signum: the signal catched if any or zero at the beginning + * - void *arg: the parameter 'argument' + * + * A typical implementation of the job callback is: + * + * void my_job_cb(int signum, void *arg) + * { + * struct myarg_t *myarg = arg; + * if (signum) + * AFB_API_ERROR(myarg->api, "job interrupted with signal %s", strsignal(signum)); + * else + * really_do_my_job(myarg); + * } + * + * @param api the api that queue the job + * @param callback the job as a callback function + * @param argument the argument to pass to the queued job + * @param group the group of the job, NULL if no group + * @param timeout the timeout of execution of the job + * + * @return 0 in case of success or -1 in case of error with errno set appropriately. + */ +int afb_api_queue_job( + afb_api_t api, + void (*callback)(int signum, void *arg), + void *argument, + void *group, + int timeout); +``` + +## Event functions + +### afb_api_broadcast_event + +```C +/** + * Broadcasts widely the event of 'name' with the data 'object'. + * 'object' can be NULL. + * + * For convenience, the function calls 'json_object_put' for 'object'. + * Thus, in the case where 'object' should remain available after + * the function returns, the function 'json_object_get' shall be used. + * + * Calling this function is only forbidden during preinit. + * + * The event sent as the name API/name where API is the name of the + * api. + * + * @param api the api that broadcast the event + * @param name the event name suffix + * @param object the object that comes with the event + * + * @return the count of clients that received the event. + */ +int afb_api_broadcast_event( + afb_api_t api, + const char *name, + struct json_object *object); +``` + +### afb_api_make_event + +```C +/** + * Creates an event of 'name' and returns it. + * + * Calling this function is only forbidden during preinit. + * + * See afb_event_is_valid to check if there is an error. + * + * The event created as the name API/name where API is the name of the + * api. + * + * @param api the api that creates the event + * @param name the event name suffix + * + * @return the created event. Use the function afb_event_is_valid to check + * whether the event is valid (created) or not (error as reported by errno). + * + * @see afb_event_is_valid + */ +afb_event_t afb_api_make_event( + afb_api_t api, + const char *name); +``` + +### afb_api_event_handler_add + +```C +/** + * Add a specific event handler for the api + * + * The handler callback is called when an event matching the given pattern + * is received (it is received if broadcasted or after subscription through + * a call or a subcall). + * + * The handler callback receive 4 arguments: + * + * - the closure given here + * - the event full name + * - the companion JSON object of the event + * - the api that subscribed the event + * + * @param api the api that creates the handler + * @param pattern the global pattern of the event to handle + * @param callback the handler callback function + * @param closure the closure of the handler + * + * @return 0 in case of success or -1 on failure with errno set + * + * @see afb_api_on_event + * @see afb_api_event_handler_del + */ +int afb_api_event_handler_add( + afb_api_t api, + const char *pattern, + void (*callback)( + void *, + const char*, + struct json_object*, + afb_api_t), + void *closure); +``` + +### afb_api_event_handler_del + +```C +/** + * Delete a specific event handler for the api + * + * @param api the api that the handler belongs to + * @param pattern the global pattern of the handler to remove + * @param closure if not NULL it will receive the closure set to the handler + * + * @return 0 in case of success or -1 on failure with errno set + * + * @see afb_api_on_event + * @see afb_api_event_handler_add + */ +int afb_api_event_handler_del( + afb_api_t api, + const char *pattern, + void **closure); + +``` + +## Systemd functions + +### afb_api_get_event_loop + +```C +/** + * Retrieves the common systemd's event loop of AFB + * + * @param api the api that uses the event loop + * + * @return the systemd event loop if active, NULL otherwise + * + * @see afb_api_get_user_bus + * @see afb_api_get_system_bus + */ +struct sd_event *afb_api_get_event_loop( + afb_api_t api); +``` + +### afb_api_get_user_bus + +```C +/** + * Retrieves the common systemd's user/session d-bus of AFB + * + * @param api the api that uses the user dbus + * + * @return the systemd user connection to dbus if active, NULL otherwise + * + * @see afb_api_get_event_loop + * @see afb_api_get_system_bus + */ +struct sd_bus *afb_api_get_user_bus( + afb_api_t api); +``` + +### afb_api_get_system_bus + +```C +/** + * Retrieves the common systemd's system d-bus of AFB + * + * @param api the api that uses the system dbus + * + * @return the systemd system connection to dbus if active, NULL otherwise + * + * @see afb_api_get_event_loop + * @see afb_api_get_user_bus + */ +struct sd_bus *afb_api_get_system_bus( + afb_api_t api); +``` + + +## Dynamic api functions + +### afb_api_new_api + +```C +/** + * Creates a new api of name 'apiname' briefly described by 'info' (that can + * be NULL). + * + * When the pre-initialization function is given, it is a function that + * receives 2 parameters: + * + * - the closure as given in the call + * - the created api that can be initialised + * + * This pre-initialization function must return a negative value to abort + * the creation of the api. Otherwise, it returns a non-negative value to + * continue. + * + * @param api the api that creates the other one + * @param apiname the name of the new api + * @param info the brief description of the new api (can be NULL) + * @param noconcurrency zero or not zero whether the new api is reentrant or not + * @param preinit the pre-initialization function if any (can be NULL) + * @param closure the closure for the pre-initialization \ref preinit + * + * @return 0 in case of success or -1 on failure with errno set + * + * @see afb_api_delete_api + */ +afb_api_t afb_api_new_api( + afb_api_t api, + const char *apiname, + const char *info, + int noconcurrency, + int (*preinit)(void*, afb_api_t ), + void *closure); +``` + +### afb_api_set_verbs_v2 + +```C +/** + * @deprecated use @ref afb_api_set_verbs_v3 instead + * + * Set the verbs of the 'api' using description of verbs of the api v2 + * + * @param api the api that will get the verbs + * @param verbs the array of verbs to add terminated with an item with name=NULL + * + * @return 0 in case of success or -1 on failure with errno set + * + * @see afb_verb_v2 + * @see afb_api_add_verb + * @see afb_api_set_verbs_v3 + */ +int afb_api_set_verbs_v2( + afb_api_t api, + const struct afb_verb_v2 *verbs); +``` + +### afb_api_set_verbs_v3 + +```C +/** + * Set the verbs of the 'api' using description of verbs of the api v2 + * + * @param api the api that will get the verbs + * @param verbs the array of verbs to add terminated with an item with name=NULL + * + * @return 0 in case of success or -1 on failure with errno set + * + * @see afb_verb_v3 + * @see afb_api_add_verb + * @see afb_api_del_verb + */ +int afb_api_set_verbs_v3( + afb_api_t api, + const struct afb_verb_v3 *verbs); +``` + +### afb_api_add_verb + +```C +/** + * Add one verb to the dynamic set of the api + * + * @param api the api to change + * @param verb name of the verb + * @param info brief description of the verb, can be NULL + * @param callback callback function implementing the verb + * @param vcbdata data for the verb callback, available through req + * @param auth required authorization, can be NULL + * @param session authorization and session requirements of the verb + * @param glob is the verb glob name + * + * @return 0 in case of success or -1 on failure with errno set + * + * @see afb_verb_v3 + * @see afb_api_del_verb + * @see afb_api_set_verbs_v3 + * @see fnmatch for matching names using glob + */ +int afb_api_add_verb( + afb_api_t api, + const char *verb, + const char *info, + void (*callback)(struct afb_req_x2 *req), + void *vcbdata, + const struct afb_auth *auth, + uint32_t session, + int glob); +``` + +### afb_api_del_verb + +```C +/** + * Delete one verb from the dynamic set of the api + * + * @param api the api to change + * @param verb name of the verb to delete + * @param vcbdata if not NULL will receive the vcbdata of the deleted verb + * + * @return 0 in case of success or -1 on failure with errno set + * + * @see afb_api_add_verb + */ +int afb_api_del_verb( + afb_api_t api, + const char *verb, + void **vcbdata); +``` + +### afb_api_on_event + +```C +/** + * Set the callback 'onevent' to process events in the name of the 'api'. + * + * This setting can be done statically using the global variable + * @ref afbBindingV3. + * + * This function replace any previously global event callback set. + * + * When an event is received, the callback 'onevent' is called with 3 parameters + * + * - the api that recorded the event handler + * - the full name of the event + * - the companion JSON object of the event + * + * @param api the api that wants to process events + * @param onevent the callback function that will process events (can be NULL + * to remove event callback) + * + * @return 0 in case of success or -1 on failure with errno set + * + * @see afbBindingV3 + * @see afb_binding_v3 + * @see afb_api_event_handler_add + * @see afb_api_event_handler_del + */ +int afb_api_on_event( + afb_api_t api, + void (*onevent)( + afb_api_t api, + const char *event, + struct json_object *object)); +``` + +### afb_api_on_init + +```C +/** + * Set the callback 'oninit' to process initialization of the 'api'. + * + * This setting can be done statically using the global variable + * @ref afbBindingV3 + * + * This function replace any previously initialization callback set. + * + * This function is only valid during the pre-initialization stage. + * + * The callback initialization function will receive one argument: the api + * to initialize. + * + * @param api the api that wants to process events + * @param oninit the callback function that initialize the api + * + * @return 0 in case of success or -1 on failure with errno set + * + * @see afbBindingV3 + * @see afb_binding_v3 + */ +int afb_api_on_init( + afb_api_t api, + int (*oninit)(afb_api_t api)); +``` + +### afb_api_provide_class + +```C +/** + * Tells that the api provides a class of features. Classes are intended to + * allow ordering of initializations: apis that provides a given class are + * initialized before apis requiring it. + * + * This function is only valid during the pre-initialization stage. + * + * @param api the api that provides the classes + * @param name a space separated list of the names of the provided classes + * + * @returns 0 in case of success or a negative value in case of error. + * + * @see afb_api_require_class + */ +int afb_api_provide_class( + afb_api_t api, + const char *name); +``` + +### afb_api_require_class + +```C +/** + * Tells that the api requires a set of class features. Classes are intended to + * allow ordering of initializations: apis that provides a given class are + * initialized before apis requiring it. + * + * This function is only valid during the pre-initialization stage. + * + * @param api the api that requires the classes + * @param name a space separated list of the names of the required classes + * + * @returns 0 in case of success or a negative value in case of error. + * + * @see afb_api_provide_class + */ +int afb_api_require_class( + afb_api_t api, + const char *name); +``` + +### afb_api_seal + +```C +/** + * Seal the api. After a call to this function the api can not be modified + * anymore. + * + * @param api the api to be sealed + */ +void afb_api_seal( + afb_api_t api); +``` + +### afb_api_delete_api + +```C +/** + * Delete the given api. + * + * It is of the responsibility of the caller to don't used the deleted api + * anymore after this function returned. + * + * @param api the api to delete + * + * @returns 0 in case of success or a negative value in case of error. + * + * @see afb_api_new_api + */ +int afb_api_delete_api( + afb_api_t api); +``` + +### afb_api_add_alias + +```C +/** + * Create an aliased name 'as_name' for the api 'name'. + * Calling this function is only allowed within preinit. + * + * @param api the api that requires the aliasing + * @param name the api to alias + * @param as_name the aliased name of the aliased api + * + * @return 0 in case of success or -1 in case of error with errno set appropriately. + */ +int afb_api_add_alias( + afb_api_t api, + const char *name, + const char *as_name); +``` + + +## Legacy functions + +The function for legacy calls are still provided for some time because +adaptation of existing code to the new call functions require a small amount +of work. + +### afb_api_call_legacy + +```C +/** + * @deprecated try to use @ref afb_api_call instead + * + * * Calls the 'verb' of the 'api' with the arguments 'args' and 'verb' in the name of the binding. + * The result of the call is delivered to the 'callback' function with the 'callback_closure'. + * + * For convenience, the function calls 'json_object_put' for 'args'. + * Thus, in the case where 'args' should remain available after + * the function returns, the function 'json_object_get' shall be used. + * + * The 'callback' receives 3 arguments: + * 1. 'closure' the user defined closure pointer 'closure', + * 2. 'status' a status being 0 on success or negative when an error occurred, + * 2. 'result' the resulting data as a JSON object. + * + * @param api The api + * @param apiname The api name of the method to call + * @param verb The verb name of the method to call + * @param args The arguments to pass to the method + * @param callback The to call on completion + * @param closure The closure to pass to the callback + * + * @see also 'afb_api_call' + * @see also 'afb_api_call_sync' + * @see also 'afb_api_call_sync_legacy' + * @see also 'afb_req_subcall' + * @see also 'afb_req_subcall_sync' + */ +void afb_api_call_legacy( + afb_api_t api, + const char *apiname, + const char *verb, + struct json_object *args, + void (*callback)( + void *closure, + int status, + struct json_object *result, + afb_api_t api), + void *closure); +``` + +### afb_api_call_sync_legacy + +```C +/** + * @deprecated try to use @ref afb_api_call_sync instead + * + * Calls the 'verb' of the 'api' with the arguments 'args' and 'verb' in the name of the binding. + * 'result' will receive the response. + * + * For convenience, the function calls 'json_object_put' for 'args'. + * Thus, in the case where 'args' should remain available after + * the function returns, the function 'json_object_get' shall be used. + * + * @param api The api + * @param apiname The api name of the method to call + * @param verb The verb name of the method to call + * @param args The arguments to pass to the method + * @param result Where to store the result - should call json_object_put on it - + * + * @returns 0 in case of success or a negative value in case of error. + * + * @see also 'afb_api_call' + * @see also 'afb_api_call_sync' + * @see also 'afb_api_call_legacy' + * @see also 'afb_req_subcall' + * @see also 'afb_req_subcall_sync' + */ +int afb_api_call_sync_legacy( + afb_api_t api, + const char *apiname, + const char *verb, + struct json_object *args, + struct json_object **result); +``` + |