1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
|
/*
*
* Copyright 2016, Google Inc.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following disclaimer
* in the documentation and/or other materials provided with the
* distribution.
* * Neither the name of Google Inc. nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/
/*
* wakeup_fd_cv uses condition variables to implement wakeup fds.
*
* It is intended for use only in cases when eventfd() and pipe() are not
* available. It can only be used with the "poll" engine.
*
* Implementation:
* A global table of cv wakeup fds is mantained. A cv wakeup fd is a negative
* file descriptor. poll() is then run in a background thread with only the
* real socket fds while we wait on a condition variable trigged by either the
* poll() completion or a wakeup_fd() call.
*
*/
#ifndef GRPC_CORE_LIB_IOMGR_WAKEUP_FD_CV_H
#define GRPC_CORE_LIB_IOMGR_WAKEUP_FD_CV_H
#include <grpc/support/sync.h>
#include "src/core/lib/iomgr/ev_posix.h"
#define FD_TO_IDX(fd) (-(fd)-1)
#define IDX_TO_FD(idx) (-(idx)-1)
typedef struct cv_node {
gpr_cv* cv;
struct cv_node* next;
} cv_node;
typedef struct fd_node {
int is_set;
cv_node* cvs;
struct fd_node* next_free;
} fd_node;
typedef struct cv_fd_table {
gpr_mu mu;
int pollcount;
int shutdown;
gpr_cv shutdown_complete;
fd_node* cvfds;
fd_node* free_fds;
unsigned int size;
grpc_poll_function_type poll;
} cv_fd_table;
#endif /* GRPC_CORE_LIB_IOMGR_WAKEUP_FD_CV_H */
|
