op: lib for async operations

1 files changed, 155 insertions, 0 deletions

diff --git a/src/include/gnunet_op_lib.h b/src/include/gnunet_op_lib.h
new file mode 100644
index 000000000..d170570a4
--- /dev/null
+++ b/src/include/gnunet_op_lib.h
@@ -0,0 +1,155 @@
+/*
+     This file is part of GNUnet.
+     Copyright (C) 2016 GNUnet e.V.
+
+     GNUnet is free software; you can redistribute it and/or modify
+     it under the terms of the GNU General Public License as published
+     by the Free Software Foundation; either version 3, or (at your
+     option) any later version.
+
+     GNUnet is distributed in the hope that it will be useful, but
+     WITHOUT ANY WARRANTY; without even the implied warranty of
+     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+     General Public License for more details.
+
+     You should have received a copy of the GNU General Public License
+     along with GNUnet; see the file COPYING.  If not, write to the
+     Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+     Boston, MA 02110-1301, USA.
+*/
+
+/**
+ * @file
+ * Asynchronous operations; register callbacks for operations and call them when a response arrives.
+ *
+ * @author Gabor X Toth
+ */
+
+#ifndef GNUNET_OP_H
+#define GNUNET_OP_H
+
+#include "gnunet_util_lib.h"
+
+/**
+ * Operations handle.
+ */
+struct GNUNET_OP_Handle;
+
+
+/**
+ * Create new operations handle.
+ */
+struct GNUNET_OP_Handle *
+GNUNET_OP_create ();
+
+
+/**
+ * Destroy operations handle.
+ */
+void
+GNUNET_OP_destroy (struct GNUNET_OP_Handle *h);
+
+
+/**
+ * Get a unique operation ID to distinguish between asynchronous requests.
+ *
+ * @param h
+ *        Operations handle.
+ *
+ * @return Operation ID to use.
+ */
+uint64_t
+GNUNET_OP_get_next_id (struct GNUNET_OP_Handle *h);
+
+
+/**
+ * Find operation by ID.
+ *
+ * @param h
+ *        Operations handle.
+ * @param op_id
+ *        Operation ID to look up.
+ * @param[out] result_cb
+ *        If an operation was found, its result callback is returned here.
+ * @param[out] cls
+ *        If an operation was found, its closure is returned here.
+ * @param[out] ctx
+ *        User context.
+ *
+ * @return #GNUNET_YES if an operation was found,
+ *         #GNUNET_NO  if not found.
+ */
+int
+GNUNET_OP_get (struct GNUNET_OP_Handle *h,
+               uint64_t op_id,
+               GNUNET_ResultCallback *result_cb,
+               void **cls,
+               void **ctx);
+
+
+/**
+ * Add a new operation.
+ *
+ * @param h
+ *        Operations handle.
+ * @param result_cb
+ *        Function to call with the result of the operation.
+ * @param cls
+ *        Closure for @a result_cb.
+ * @param ctx
+ *        User context.
+ *
+ * @return ID of the new operation.
+ */
+uint64_t
+GNUNET_OP_add (struct GNUNET_OP_Handle *h,
+               GNUNET_ResultCallback result_cb,
+               void *cls,
+               void *ctx);
+
+
+/**
+ * Call the result callback of an operation and remove it.
+ *
+ * @param h
+ *        Operations handle.
+ * @param op_id
+ *        Operation ID.
+ * @param result_code
+ *        Result of the operation.
+ * @param data
+ *        Data result of the operation.
+ * @param data_size
+ *        Size of @a data.
+ * @param[out] ctx
+ *        User context.
+ *
+ * @return #GNUNET_YES if the operation was found and removed,
+ *         #GNUNET_NO  if the operation was not found.
+ */
+int
+GNUNET_OP_result (struct GNUNET_OP_Handle *h,
+                  uint64_t op_id,
+                  int64_t result_code,
+                  const void *data,
+                  uint16_t data_size,
+                  void **ctx);
+
+
+/**
+ * Remove / cancel an operation.
+ *
+ * @param h
+ *        Operations handle.
+ * @param op_id
+ *        Operation ID.
+ *
+ * @return #GNUNET_YES if the operation was found and removed,
+ *         #GNUNET_NO  if the operation was not found.
+ */
+int
+GNUNET_OP_remove (struct GNUNET_OP_Handle *h,
+                  uint64_t op_id);
+
+
+#endif // GNUNET_OP_H