xref: /libuv/src/win/async.c (revision d54c92e3)
1 /* Copyright Joyent, Inc. and other Node contributors. All rights reserved.
2  *
3  * Permission is hereby granted, free of charge, to any person obtaining a copy
4  * of this software and associated documentation files (the "Software"), to
5  * deal in the Software without restriction, including without limitation the
6  * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
7  * sell copies of the Software, and to permit persons to whom the Software is
8  * furnished to do so, subject to the following conditions:
9  *
10  * The above copyright notice and this permission notice shall be included in
11  * all copies or substantial portions of the Software.
12  *
13  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
14  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
15  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
16  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
17  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
18  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
19  * IN THE SOFTWARE.
20  */
21 
22 #include <assert.h>
23 
24 #include "uv.h"
25 #include "internal.h"
26 #include "atomicops-inl.h"
27 #include "handle-inl.h"
28 #include "req-inl.h"
29 
30 
uv__async_endgame(uv_loop_t * loop,uv_async_t * handle)31 void uv__async_endgame(uv_loop_t* loop, uv_async_t* handle) {
32   if (handle->flags & UV_HANDLE_CLOSING &&
33       !handle->async_sent) {
34     assert(!(handle->flags & UV_HANDLE_CLOSED));
35     uv__handle_close(handle);
36   }
37 }
38 
39 
uv_async_init(uv_loop_t * loop,uv_async_t * handle,uv_async_cb async_cb)40 int uv_async_init(uv_loop_t* loop, uv_async_t* handle, uv_async_cb async_cb) {
41   uv_req_t* req;
42 
43   uv__handle_init(loop, (uv_handle_t*) handle, UV_ASYNC);
44   handle->async_sent = 0;
45   handle->async_cb = async_cb;
46 
47   req = &handle->async_req;
48   UV_REQ_INIT(req, UV_WAKEUP);
49   req->data = handle;
50 
51   uv__handle_start(handle);
52 
53   return 0;
54 }
55 
56 
uv__async_close(uv_loop_t * loop,uv_async_t * handle)57 void uv__async_close(uv_loop_t* loop, uv_async_t* handle) {
58   if (!((uv_async_t*)handle)->async_sent) {
59     uv__want_endgame(loop, (uv_handle_t*) handle);
60   }
61 
62   uv__handle_closing(handle);
63 }
64 
65 
uv_async_send(uv_async_t * handle)66 int uv_async_send(uv_async_t* handle) {
67   uv_loop_t* loop = handle->loop;
68 
69   if (handle->type != UV_ASYNC) {
70     /* Can't set errno because that's not thread-safe. */
71     return -1;
72   }
73 
74   /* The user should make sure never to call uv_async_send to a closing or
75    * closed handle. */
76   assert(!(handle->flags & UV_HANDLE_CLOSING));
77 
78   if (!uv__atomic_exchange_set(&handle->async_sent)) {
79     POST_COMPLETION_FOR_REQ(loop, &handle->async_req);
80   }
81 
82   return 0;
83 }
84 
85 
uv__process_async_wakeup_req(uv_loop_t * loop,uv_async_t * handle,uv_req_t * req)86 void uv__process_async_wakeup_req(uv_loop_t* loop, uv_async_t* handle,
87     uv_req_t* req) {
88   assert(handle->type == UV_ASYNC);
89   assert(req->type == UV_WAKEUP);
90 
91   handle->async_sent = 0;
92 
93   if (handle->flags & UV_HANDLE_CLOSING) {
94     uv__want_endgame(loop, (uv_handle_t*)handle);
95   } else if (handle->async_cb != NULL) {
96     handle->async_cb(handle);
97   }
98 }
99