Create doxygen comments for async_req.[ch]

(This used to be commit 1dab45b16a23b1126fbf29890747a2b256f08968)

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) {