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Diffstat (limited to 'include/afb/afb-req-common.h')
| -rw-r--r-- | include/afb/afb-req-common.h | 400 |
1 files changed, 400 insertions, 0 deletions
diff --git a/include/afb/afb-req-common.h b/include/afb/afb-req-common.h new file mode 100644 index 00000000..8ff1b39b --- /dev/null +++ b/include/afb/afb-req-common.h @@ -0,0 +1,400 @@ +/* + * Copyright (C) 2016, 2017 "IoT.bzh" + * Author: José Bollo <jose.bollo@iot.bzh> + * + * Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#pragma once + +#include <stdarg.h> + +#include "afb-event-itf.h" + +struct json_object; +struct afb_stored_req; + +/* + * Describes an argument (or parameter) of a request + */ +struct afb_arg +{ + const char *name; /* name of the argument or NULL if invalid */ + const char *value; /* string representation of the value of the argument */ + /* original filename of the argument if path != NULL */ + const char *path; /* if not NULL, path of the received file for the argument */ + /* when the request is finalized this file is removed */ +}; + +/* + * Interface for handling requests. + * It records the functions to be called for the request. + * Don't use this structure directly. + * Use the helper functions documented below. + */ +struct afb_req_itf +{ + /* CAUTION: respect the order, add at the end */ + + struct json_object *(*json)(void *closure); + struct afb_arg (*get)(void *closure, const char *name); + + void (*success)(void *closure, struct json_object *obj, const char *info); + void (*fail)(void *closure, const char *status, const char *info); + + void (*vsuccess)(void *closure, struct json_object *obj, const char *fmt, va_list args); + void (*vfail)(void *closure, const char *status, const char *fmt, va_list args); + + void *(*context_get)(void *closure); + void (*context_set)(void *closure, void *value, void (*free_value)(void*)); + + void (*addref)(void *closure); + void (*unref)(void *closure); + + void (*session_close)(void *closure); + int (*session_set_LOA)(void *closure, unsigned level); + + int (*subscribe)(void *closure, struct afb_event event); + int (*unsubscribe)(void *closure, struct afb_event event); + + void (*subcall)(void *closure, const char *api, const char *verb, struct json_object *args, void (*callback)(void*, int, struct json_object*), void *cb_closure); + int (*subcallsync)(void *closure, const char *api, const char *verb, struct json_object *args, struct json_object **result); + + void (*vverbose)(void *closure, int level, const char *file, int line, const char * func, const char *fmt, va_list args); + struct afb_stored_req *(*store)(void *closure); +}; + +/* + * Describes the request by bindings from afb-daemon + */ +struct afb_req +{ + const struct afb_req_itf *itf; /* the interface to use */ + void *closure; /* the closure argument for functions of 'itf' */ +}; + +/* + * Checks wether the request 'req' is valid or not. + * + * Returns 0 if not valid or 1 if valid. + */ +static inline int afb_req_is_valid(struct afb_req req) +{ + return req.itf != NULL; +} + +/* + * Gets from the request 'req' the argument of 'name'. + * Returns a PLAIN structure of type 'struct afb_arg'. + * When the argument of 'name' is not found, all fields of result are set to NULL. + * When the argument of 'name' is found, the fields are filled, + * in particular, the field 'result.name' is set to 'name'. + * + * There is a special name value: the empty string. + * The argument of name "" is defined only if the request was made using + * an HTTP POST of Content-Type "application/json". In that case, the + * argument of name "" receives the value of the body of the HTTP request. + */ +static inline struct afb_arg afb_req_get(struct afb_req req, const char *name) +{ + return req.itf->get(req.closure, name); +} + +/* + * Gets from the request 'req' the string value of the argument of 'name'. + * Returns NULL if when there is no argument of 'name'. + * Returns the value of the argument of 'name' otherwise. + * + * Shortcut for: afb_req_get(req, name).value + */ +static inline const char *afb_req_value(struct afb_req req, const char *name) +{ + return afb_req_get(req, name).value; +} + +/* + * Gets from the request 'req' the path for file attached to the argument of 'name'. + * Returns NULL if when there is no argument of 'name' or when there is no file. + * Returns the path of the argument of 'name' otherwise. + * + * Shortcut for: afb_req_get(req, name).path + */ +static inline const char *afb_req_path(struct afb_req req, const char *name) +{ + return afb_req_get(req, name).path; +} + +/* + * Gets from the request 'req' the json object hashing the arguments. + * The returned object must not be released using 'json_object_put'. + */ +static inline struct json_object *afb_req_json(struct afb_req req) +{ + return req.itf->json(req.closure); +} + +/* + * Sends a reply of kind success to the request 'req'. + * The status of the reply is automatically set to "success". + * Its send the object 'obj' (can be NULL) with an + * informationnal comment 'info (can also be NULL). + * + * For convenience, the function calls 'json_object_put' for 'obj'. + * Thus, in the case where 'obj' should remain available after + * the function returns, the function 'json_object_get' shall be used. + */ +static inline void afb_req_success(struct afb_req req, struct json_object *obj, const char *info) +{ + req.itf->success(req.closure, obj, info); +} + +/* + * Same as 'afb_req_success' but the 'info' is a formatting + * string followed by arguments. + * + * For convenience, the function calls 'json_object_put' for 'obj'. + * Thus, in the case where 'obj' should remain available after + * the function returns, the function 'json_object_get' shall be used. + */ +static inline void afb_req_success_f(struct afb_req req, struct json_object *obj, const char *info, ...) __attribute__((format(printf, 3, 4))); +static inline void afb_req_success_f(struct afb_req req, struct json_object *obj, const char *info, ...) +{ + va_list args; + va_start(args, info); + req.itf->vsuccess(req.closure, obj, info, args); + va_end(args); +} + +/* + * Same as 'afb_req_success_f' but the arguments to the format 'info' + * are given as a variable argument list instance. + * + * For convenience, the function calls 'json_object_put' for 'obj'. + * Thus, in the case where 'obj' should remain available after + * the function returns, the function 'json_object_get' shall be used. + */ +static inline void afb_req_success_v(struct afb_req req, struct json_object *obj, const char *info, va_list args) +{ + req.itf->vsuccess(req.closure, obj, info, args); +} + +/* + * Sends a reply of kind failure to the request 'req'. + * The status of the reply is set to 'status' and an + * informationnal comment 'info' (can also be NULL) can be added. + * + * Note that calling afb_req_fail("success", info) is equivalent + * to call afb_req_success(NULL, info). Thus even if possible it + * is strongly recommanded to NEVER use "success" for status. + */ +static inline void afb_req_fail(struct afb_req req, const char *status, const char *info) +{ + req.itf->fail(req.closure, status, info); +} + +/* + * Same as 'afb_req_fail' but the 'info' is a formatting + * string followed by arguments. + */ +static inline void afb_req_fail_f(struct afb_req req, const char *status, const char *info, ...) __attribute__((format(printf, 3, 4))); +static inline void afb_req_fail_f(struct afb_req req, const char *status, const char *info, ...) +{ + va_list args; + va_start(args, info); + req.itf->vfail(req.closure, status, info, args); + va_end(args); +} + +/* + * Same as 'afb_req_fail_f' but the arguments to the format 'info' + * are given as a variable argument list instance. + */ +static inline void afb_req_fail_v(struct afb_req req, const char *status, const char *info, va_list args) +{ + req.itf->vfail(req.closure, status, info, args); +} + +/* + * Gets the pointer stored by the binding for the session of 'req'. + * When the binding has not yet recorded a pointer, NULL is returned. + */ +static inline void *afb_req_context_get(struct afb_req req) +{ + return req.itf->context_get(req.closure); +} + +/* + * Stores for the binding the pointer 'context' to the session of 'req'. + * The function 'free_context' will be called when the session is closed + * or if binding stores an other pointer. + */ +static inline void afb_req_context_set(struct afb_req req, void *context, void (*free_context)(void*)) +{ + req.itf->context_set(req.closure, context, free_context); +} + +/* + * Gets the pointer stored by the binding for the session of 'req'. + * If the stored pointer is NULL, indicating that no pointer was + * already stored, afb_req_context creates a new context by calling + * the function 'create_context' and stores it with the freeing function + * 'free_context'. + */ +static inline void *afb_req_context(struct afb_req req, void *(*create_context)(), void (*free_context)(void*)) +{ + void *result = afb_req_context_get(req); + if (result == NULL) { + result = create_context(); + afb_req_context_set(req, result, free_context); + } + return result; +} + +/* + * Frees the pointer stored by the binding for the session of 'req' + * and sets it to NULL. + * + * Shortcut for: afb_req_context_set(req, NULL, NULL) + */ +static inline void afb_req_context_clear(struct afb_req req) +{ + afb_req_context_set(req, NULL, NULL); +} + +/* + * Adds one to the count of references of 'req'. + * This function MUST be called by asynchronous implementations + * of verbs if no reply was sent before returning. + */ +static inline void afb_req_addref(struct afb_req req) +{ + req.itf->addref(req.closure); +} + +/* + * Substracts one to the count of references of 'req'. + * This function MUST be called by asynchronous implementations + * of verbs after sending the asynchronous reply. + */ +static inline void afb_req_unref(struct afb_req req) +{ + req.itf->unref(req.closure); +} + +/* + * Closes the session associated with 'req' + * and delete all associated contexts. + */ +static inline void afb_req_session_close(struct afb_req req) +{ + req.itf->session_close(req.closure); +} + +/* + * Sets the level of assurance of the session of 'req' + * to 'level'. The effect of this function is subject of + * security policies. + * Returns 1 on success or 0 if failed. + */ +static inline int afb_req_session_set_LOA(struct afb_req req, unsigned level) +{ + return req.itf->session_set_LOA(req.closure, level); +} + +/* + * Establishes for the client link identified by 'req' a subscription + * to the 'event'. + * Returns 0 in case of successful subscription or -1 in case of error. + */ +static inline int afb_req_subscribe(struct afb_req req, struct afb_event event) +{ + return req.itf->subscribe(req.closure, event); +} + +/* + * Revokes the subscription established to the 'event' for the client + * link identified by 'req'. + * Returns 0 in case of successful subscription or -1 in case of error. + */ +static inline int afb_req_unsubscribe(struct afb_req req, struct afb_event event) +{ + return req.itf->unsubscribe(req.closure, event); +} + +/* + * Makes a call to the method of name 'api' / 'verb' with the object 'args'. + * This call is made in the context of the request 'req'. + * On completion, the function 'callback' is invoked with the + * 'closure' given at call and two other parameters: 'iserror' and 'result'. + * 'iserror' is a boolean that indicates if the reply is an error reply. + * 'result' is the json object of the reply, you must not call json_object_put + * on the result. + * + * 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. + */ +static inline void afb_req_subcall(struct afb_req req, const char *api, const char *verb, struct json_object *args, void (*callback)(void *closure, int iserror, struct json_object *result), void *closure) +{ + req.itf->subcall(req.closure, api, verb, args, callback, closure); +} + +/* + * Makes a call to the method of name 'api' / 'verb' with the object 'args'. + * This call is made in the context of the request 'req'. + * This call is synchronous, it waits untill completion of the request. + * It returns 0 on an error answer and returns 1 when no error was detected. + * The object pointed by 'result' is filled and must be released by the caller + * after its use by calling 'json_object_put'. + * + * 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. + */ +static inline int afb_req_subcall_sync(struct afb_req req, const char *api, const char *verb, struct json_object *args, struct json_object **result) +{ + return req.itf->subcallsync(req.closure, api, verb, args, result); +} + +/* + * Send associated to 'req' a message described by 'fmt' and following parameters + * to the journal for the verbosity 'level'. + * + * '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 + */ +static inline void afb_req_verbose(struct afb_req req, int level, const char *file, int line, const char * func, const char *fmt, ...) __attribute__((format(printf, 6, 7))); +static inline void afb_req_verbose(struct afb_req req, int level, const char *file, int line, const char * func, const char *fmt, ...) +{ + va_list args; + va_start(args, fmt); + req.itf->vverbose(req.closure, level, file, line, func, fmt, args); + va_end(args); +} + +/* macro for setting file, line and function automatically */ +# if !defined(AFB_BINDING_PRAGMA_NO_VERBOSE_DETAILS) +#define AFB_REQ_VERBOSE(req,level,...) afb_req_verbose(req,level,__FILE__,__LINE__,__func__,__VA_ARGS__) +#else +#define AFB_REQ_VERBOSE(req,level,...) afb_req_verbose(req,level,NULL,0,NULL,__VA_ARGS__) +#endif |