async-io-common.h revision c8aa2c570d30098da59f1967d5158024ed28570d 
1/*
2 * Copyright (C) 2011 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#ifndef ANDROID_ASYNC_IO_COMMON_H_
18#define ANDROID_ASYNC_IO_COMMON_H_
19
20/*
21 * Contains declarations common for asynchronous socket I/O
22 */
23
24/* Enumerates asynchronous I/O states.
25 * Values from this enum are passed to callbacks associated with an I/O,
26 * indicating at what state the I/O is. */
27typedef enum AsyncIOState {
28    /* Asynchronous I/O has been queued.                (0) */
29    ASIO_STATE_QUEUED,
30    /* Asynchronous I/O has started. This state indicates that I/O has been
31     * performed for the first time.                    (1) */
32    ASIO_STATE_STARTED,
33    /* Asynchronous I/O is continuing. This state indicates that I/O has been
34     * invoked for the second (or more) time.           (2) */
35    ASIO_STATE_CONTINUES,
36    /* Asynchronous I/O is about to be retried.         (3) */
37    ASIO_STATE_RETRYING,
38    /* Asynchronous I/O has been successfuly completed. (4) */
39    ASIO_STATE_SUCCEEDED,
40    /* Asynchronous I/O has failed.                     (5) */
41    ASIO_STATE_FAILED,
42    /* Asynchronous I/O has timed out.                  (6) */
43    ASIO_STATE_TIMED_OUT,
44    /* Asynchronous I/O has been cancelled (due to disconnect, for
45     * instance).                                       (7) */
46    ASIO_STATE_CANCELLED,
47    /* Asynchronous I/O is finished and is about to be discarder. This state is
48     * useful in case there is an association between an I/O and some client's
49     * component, that holds a reference associated with this I/O. When callback
50     * is invoked with this state, it means that it's safe to drop that extra
51     * reference associated with the I/O                (8) */
52    ASIO_STATE_FINISHED,
53} AsyncIOState;
54
55/* Enumerates actions to perform with an I/O on state transition.
56 * Values from this enum are returned from async I/O callbacks, indicating what
57 * action should be performed with the I/O by I/O handler. */
58typedef enum AsyncIOAction {
59    /* I/O is done. Perform default action depending on I/O type. */
60    ASIO_ACTION_DONE,
61    /* Abort the I/O. */
62    ASIO_ACTION_ABORT,
63    /* Retry the I/O. */
64    ASIO_ACTION_RETRY,
65} AsyncIOAction;
66
67#endif  /* ANDROID_ASYNC_IO_COMMON_H_ */
68