diff options
Diffstat (limited to 'include')
| -rw-r--r-- | include/afb/afb-req-itf.h | 226 |
1 files changed, 170 insertions, 56 deletions
diff --git a/include/afb/afb-req-itf.h b/include/afb/afb-req-itf.h index 454c1817..8530e05d 100644 --- a/include/afb/afb-req-itf.h +++ b/include/afb/afb-req-itf.h @@ -17,15 +17,37 @@ #pragma once +#if !defined(_GNU_SOURCE) +# error "_GNU_SOURCE must be defined for using vasprintf" +#endif + +#include <stdlib.h> +#include <stdarg.h> +#include <stdio.h> + +/* avoid inclusion of <json-c/json.h> */ struct json_object; +/* + * Describes an argument (or parameter) of a request + */ struct afb_arg { - const char *name; - const char *value; - const char *path; + 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); @@ -45,99 +67,214 @@ struct afb_req_itf { int (*session_set_LOA)(void *closure, unsigned level); }; +/* + * Describes the request by plugins from afb-daemon + */ struct afb_req { - const struct afb_req_itf *itf; - void *closure; + const struct afb_req_itf *itf; /* the interface to use */ + void *closure; /* the closure argument for functions of 'itf' */ }; +/* + * 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). + */ static inline void afb_req_success(struct afb_req req, struct json_object *obj, const char *info) { req.itf->success(req.closure, obj, info); } -static inline void afb_req_fail(struct afb_req req, const char *status, const char *info) +/* + * Same as 'afb_req_success' but the 'info' is a formatting + * string followed by arguments. + */ +static inline void afb_req_success_f(struct afb_req req, struct json_object *obj, const char *info, ...) { - req.itf->fail(req.closure, status, info); + char *message; + va_list args; + va_start(args, info); + if (info == NULL || vasprintf(&message, info, args) < 0) + message = NULL; + va_end(args); + afb_req_success(req, obj, message); + free(message); } -static inline const char *afb_req_raw(struct afb_req req, size_t *size) +/* + * 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) { - return req.itf->raw(req.closure, size); + req.itf->fail(req.closure, status, info); } -static inline void afb_req_send(struct afb_req req, const char *buffer, size_t size) +/* + * 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, ...) { - req.itf->send(req.closure, buffer, size); + char *message; + va_list args; + va_start(args, info); + if (info == NULL || vasprintf(&message, info, args) < 0) + message = NULL; + va_end(args); + afb_req_fail(req, status, message); + free(message); } +/* + * Gets the pointer stored by the plugin for the session of 'req'. + * When the plugin 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); } -static inline void afb_req_context_set(struct afb_req req, void *value, void (*free_value)(void*)) +/* + * Stores for the plugin the pointer 'context' to the session of 'req'. + * The function 'free_context' will be called when the session is closed + * or if plugin 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, value, free_value); + req.itf->context_set(req.closure, context, free_context); } -static inline void *afb_req_context(struct afb_req req, void *(*create_value)(), void (*free_value)(void*)) +/* + * Gets the pointer stored by the plugin 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 = req.itf->context_get(req.closure); + void *result = afb_req_context_get(req); if (result == NULL) { - result = create_value(); - if (result != NULL) - req.itf->context_set(req.closure, result, free_value); + result = create_context(); + afb_req_context_set(req, result, free_context); } return result; } +/* + * Frees the pointer stored by the plugin 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 authorisation 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); } -#include <stdlib.h> - +/* + * Stores 'req' on heap for asynchrnous use. + * Returns a pointer to the stored 'req' or NULL on memory depletion. + * The count of reference to 'req' is incremented on success + * (see afb_req_addref). + */ static inline struct afb_req *afb_req_store(struct afb_req req) { struct afb_req *result = malloc(sizeof *result); @@ -148,52 +285,29 @@ static inline struct afb_req *afb_req_store(struct afb_req req) return result; } +/* + * Retrieves the afb_req stored at 'req' and frees the memory. + * Returns the stored request. + * The count of reference is UNCHANGED, thus, normally, the + * function 'afb_req_unref' should be called on the result + * after that the asynchronous reply if sent. + */ static inline struct afb_req afb_req_unstore(struct afb_req *req) { struct afb_req result = *req; free(req); - afb_req_unref(result); return result; } -#if !defined(_GNU_SOURCE) -# error "_GNU_SOURCE must be defined for using vasprintf" -#endif - -#include <stdarg.h> -#include <stdio.h> - -static inline void afb_req_fail_v(struct afb_req req, const char *status, const char *info, va_list args) -{ - char *message; - if (info == NULL || vasprintf(&message, info, args) < 0) - message = NULL; - afb_req_fail(req, status, message); - free(message); -} - -static inline void afb_req_fail_f(struct afb_req req, const char *status, const char *info, ...) -{ - va_list args; - va_start(args, info); - afb_req_fail_v(req, status, info, args); - va_end(args); -} - -static inline void afb_req_success_v(struct afb_req req, struct json_object *obj, const char *info, va_list args) +/* internal use */ +static inline const char *afb_req_raw(struct afb_req req, size_t *size) { - char *message; - if (info == NULL || vasprintf(&message, info, args) < 0) - message = NULL; - afb_req_success(req, obj, message); - free(message); + return req.itf->raw(req.closure, size); } -static inline void afb_req_success_f(struct afb_req req, struct json_object *obj, const char *info, ...) +/* internal use */ +static inline void afb_req_send(struct afb_req req, const char *buffer, size_t size) { - va_list args; - va_start(args, info); - afb_req_success_v(req, obj, info, args); - va_end(args); + req.itf->send(req.closure, buffer, size); } |