3 * Copyright 2015 gRPC authors.
5 * Licensed under the Apache License, Version 2.0 (the "License");
6 * you may not use this file except in compliance with the License.
7 * You may obtain a copy of the License at
9 * http://www.apache.org/licenses/LICENSE-2.0
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
19 #ifndef GRPC_CORE_LIB_IOMGR_SOCKET_WINDOWS_H
20 #define GRPC_CORE_LIB_IOMGR_SOCKET_WINDOWS_H
22 #include <grpc/support/port_platform.h>
24 #include "src/core/lib/iomgr/port.h"
26 #ifdef GRPC_WINSOCK_SOCKET
29 #include <grpc/support/atm.h>
30 #include <grpc/support/sync.h>
32 #include "src/core/lib/iomgr/closure.h"
33 #include "src/core/lib/iomgr/iomgr_internal.h"
35 #ifndef WSA_FLAG_NO_HANDLE_INHERIT
36 #define WSA_FLAG_NO_HANDLE_INHERIT 0x80
39 /* This holds the data for an outstanding read or write on a socket.
40 The mutex to protect the concurrent access to that data is the one
41 inside the winsocket wrapper. */
42 typedef struct grpc_winsocket_callback_info {
43 /* This is supposed to be a WSAOVERLAPPED, but in order to get that
44 definition, we need to include ws2tcpip.h, which needs to be included
45 from the top, otherwise it'll clash with a previous inclusion of
46 windows.h that in turns includes winsock.h. If anyone knows a way
47 to do it properly, feel free to send a patch. */
48 OVERLAPPED overlapped;
49 /* The callback information for the pending operation. May be empty if the
50 caller hasn't registered a callback yet. */
51 grpc_closure* closure;
52 /* A boolean to describe if the IO Completion Port got a notification for
53 that operation. This will happen if the operation completed before the
54 called had time to register a callback. We could avoid that behavior
55 altogether by forcing the caller to always register its callback before
56 proceeding queue an operation, but it is frequent for an IO Completion
57 Port to trigger quickly. This way we avoid a context switch for calling
58 the callback. We also simplify the read / write operations to avoid having
59 to hold a mutex for a long amount of time. */
61 /* The results of the overlapped operation. */
62 DWORD bytes_transferred;
64 } grpc_winsocket_callback_info;
66 /* This is a wrapper to a Windows socket. A socket can have one outstanding
67 read, and one outstanding write. Doing an asynchronous accept means waiting
68 for a read operation. Doing an asynchronous connect means waiting for a
69 write operation. These are completely arbitrary ties between the operation
70 and the kind of event, because we can have one overlapped per pending
71 operation, whichever its nature is. So we could have more dedicated pending
72 operation callbacks for connect and listen. But given the scope of listen
73 and accept, we don't need to go to that extent and waste memory. Also, this
74 is closer to what happens in posix world. */
75 typedef struct grpc_winsocket {
79 grpc_winsocket_callback_info write_info;
80 grpc_winsocket_callback_info read_info;
85 /* You can't add the same socket twice to the same IO Completion Port.
86 This prevents that. */
89 grpc_closure shutdown_closure;
91 /* A label for iomgr to track outstanding objects */
92 grpc_iomgr_object iomgr_object;
95 /* Create a wrapped windows handle. This takes ownership of it, meaning that
96 it will be responsible for closing it. */
97 grpc_winsocket* grpc_winsocket_create(SOCKET socket, const char* name);
99 SOCKET grpc_winsocket_wrapped_socket(grpc_winsocket* socket);
101 /* Initiate an asynchronous shutdown of the socket. Will call off any pending
102 operation to cancel them. */
103 void grpc_winsocket_shutdown(grpc_winsocket* socket);
105 /* Destroy a socket. Should only be called if there's no pending operation. */
106 void grpc_winsocket_destroy(grpc_winsocket* socket);
108 void grpc_socket_notify_on_write(grpc_winsocket* winsocket,
109 grpc_closure* closure);
111 void grpc_socket_notify_on_read(grpc_winsocket* winsocket,
112 grpc_closure* closure);
114 void grpc_socket_become_ready(grpc_winsocket* winsocket,
115 grpc_winsocket_callback_info* ci);
117 /* Returns true if this system can create AF_INET6 sockets bound to ::1.
118 The value is probed once, and cached for the life of the process. */
119 int grpc_ipv6_loopback_available(void);
121 void grpc_wsa_socket_flags_init();
123 DWORD grpc_get_default_wsa_socket_flags();
127 #endif /* GRPC_CORE_LIB_IOMGR_SOCKET_WINDOWS_H */