diff options
Diffstat (limited to 'source3/lib')
| -rw-r--r-- | source3/lib/async_req.c | 84 |
1 files changed, 80 insertions, 4 deletions
diff --git a/source3/lib/async_req.c b/source3/lib/async_req.c index 2e85d9a38d..501a6b5524 100644 --- a/source3/lib/async_req.c +++ b/source3/lib/async_req.c @@ -19,6 +19,20 @@ #include "includes.h" +/** + * @brief Print an async_req structure + * @param[in] mem_ctx The memory context for the result + * @param[in] req The request to be printed + * @retval Text representation of req + * + * This is a default print function for async requests. Implementations should + * override this with more specific information. + * + * This function should not be used by async API users, this is non-static + * only to allow implementations to easily provide default information in + * their specific functions. + */ + char *async_req_print(TALLOC_CTX *mem_ctx, struct async_req *req) { return talloc_asprintf(mem_ctx, "async_req: state=%d, status=%s, " @@ -26,6 +40,15 @@ char *async_req_print(TALLOC_CTX *mem_ctx, struct async_req *req) talloc_get_name(req->private_data)); } +/** + * @brief Create an async request + * @param[in] mem_ctx The memory context for the result + * @param[in] ev The event context this async request will be driven by + * @retval A new async request + * + * The new async request will be initialized in state ASYNC_REQ_IN_PROGRESS + */ + struct async_req *async_req_new(TALLOC_CTX *mem_ctx, struct event_context *ev) { struct async_req *result; @@ -40,6 +63,15 @@ struct async_req *async_req_new(TALLOC_CTX *mem_ctx, struct event_context *ev) return result; } +/** + * @brief An async request has successfully finished + * @param[in] req The finished request + * + * async_req_done is to be used by implementors of async requests. When a + * request is successfully finished, this function calls the user's completion + * function. + */ + void async_req_done(struct async_req *req) { req->status = NT_STATUS_OK; @@ -49,6 +81,16 @@ void async_req_done(struct async_req *req) } } +/** + * @brief An async request has seen an error + * @param[in] req The request with an error + * @param[in] status The error code + * + * async_req_done is to be used by implementors of async requests. When a + * request can not successfully completed, the implementation should call this + * function with the appropriate status code. + */ + void async_req_error(struct async_req *req, NTSTATUS status) { req->status = status; @@ -58,6 +100,14 @@ void async_req_error(struct async_req *req, NTSTATUS status) } } +/** + * @brief Timed event callback + * @param[in] ev Event context + * @param[in] te The timed event + * @param[in] now current time + * @param[in] priv The async request to be finished + */ + static void async_trigger(struct event_context *ev, struct timed_event *te, const struct timeval *now, void *priv) { @@ -72,12 +122,21 @@ static void async_trigger(struct event_context *ev, struct timed_event *te, } } +/** + * @brief Finish a request before it started processing + * @param[in] req The finished request + * @param[in] status The success code + * + * An implementation of an async request might find that it can either finish + * the request without waiting for an external event, or it can't even start + * the engine. To present the illusion of a callback to the user of the API, + * the implementation can call this helper function which triggers an + * immediate timed event. This way the caller can use the same calling + * conventions, independent of whether the request was actually deferred. + */ + bool async_post_status(struct async_req *req, NTSTATUS status) { - /* - * Used if a request is finished before it even started - */ - req->status = status; if (event_add_timed(req->event_ctx, req, timeval_zero(), @@ -88,6 +147,23 @@ bool async_post_status(struct async_req *req, NTSTATUS status) return true; } +/** + * @brief Helper function for nomem check + * @param[in] p The pointer to be checked + * @param[in] req The request being processed + * + * Convenience helper to easily check alloc failure within a callback + * implementing the next step of an async request. + * + * Call pattern would be + * \code + * p = talloc(mem_ctx, bla); + * if (async_req_nomem(p, req)) { + * return; + * } + * \endcode + */ + bool async_req_nomem(const void *p, struct async_req *req) { if (p != NULL) { |