1 /*
2 *
3 * Copyright 2015 gRPC authors.
4 *
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
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
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.
16 *
17 */
18
19 #include <grpc/support/port_platform.h>
20
21 #include "src/core/lib/iomgr/port.h"
22
23 #ifdef GRPC_WINSOCK_SOCKET
24
25 #include <winsock2.h>
26 #include <limits>
27
28 #include <grpc/support/alloc.h>
29 #include <grpc/support/log.h>
30 #include <grpc/support/log_windows.h>
31
32 #include "src/core/lib/debug/stats.h"
33 #include "src/core/lib/gprpp/thd.h"
34 #include "src/core/lib/iomgr/iocp_windows.h"
35 #include "src/core/lib/iomgr/iomgr_internal.h"
36 #include "src/core/lib/iomgr/socket_windows.h"
37 #include "src/core/lib/iomgr/timer.h"
38
39 static ULONG g_iocp_kick_token;
40 static OVERLAPPED g_iocp_custom_overlap;
41
42 static gpr_atm g_custom_events = 0;
43
44 static HANDLE g_iocp;
45
deadline_to_millis_timeout(grpc_millis deadline)46 static DWORD deadline_to_millis_timeout(grpc_millis deadline) {
47 if (deadline == GRPC_MILLIS_INF_FUTURE) {
48 return INFINITE;
49 }
50 grpc_millis now = grpc_core::ExecCtx::Get()->Now();
51 if (deadline < now) return 0;
52 grpc_millis timeout = deadline - now;
53 if (timeout > std::numeric_limits<DWORD>::max()) return INFINITE;
54 return static_cast<DWORD>(deadline - now);
55 }
56
grpc_iocp_work(grpc_millis deadline)57 grpc_iocp_work_status grpc_iocp_work(grpc_millis deadline) {
58 BOOL success;
59 DWORD bytes = 0;
60 DWORD flags = 0;
61 ULONG_PTR completion_key;
62 LPOVERLAPPED overlapped;
63 grpc_winsocket* socket;
64 grpc_winsocket_callback_info* info;
65 GRPC_STATS_INC_SYSCALL_POLL();
66 success =
67 GetQueuedCompletionStatus(g_iocp, &bytes, &completion_key, &overlapped,
68 deadline_to_millis_timeout(deadline));
69 grpc_core::ExecCtx::Get()->InvalidateNow();
70 if (success == 0 && overlapped == NULL) {
71 return GRPC_IOCP_WORK_TIMEOUT;
72 }
73 GPR_ASSERT(completion_key && overlapped);
74 if (overlapped == &g_iocp_custom_overlap) {
75 gpr_atm_full_fetch_add(&g_custom_events, -1);
76 if (completion_key == (ULONG_PTR)&g_iocp_kick_token) {
77 /* We were awoken from a kick. */
78 return GRPC_IOCP_WORK_KICK;
79 }
80 gpr_log(GPR_ERROR, "Unknown custom completion key.");
81 abort();
82 }
83
84 socket = (grpc_winsocket*)completion_key;
85 if (overlapped == &socket->write_info.overlapped) {
86 info = &socket->write_info;
87 } else if (overlapped == &socket->read_info.overlapped) {
88 info = &socket->read_info;
89 } else {
90 abort();
91 }
92 if (socket->shutdown_called) {
93 info->bytes_transfered = 0;
94 info->wsa_error = WSA_OPERATION_ABORTED;
95 } else {
96 success = WSAGetOverlappedResult(socket->socket, &info->overlapped, &bytes,
97 FALSE, &flags);
98 info->bytes_transfered = bytes;
99 info->wsa_error = success ? 0 : WSAGetLastError();
100 }
101 GPR_ASSERT(overlapped == &info->overlapped);
102 grpc_socket_become_ready(socket, info);
103 return GRPC_IOCP_WORK_WORK;
104 }
105
grpc_iocp_init(void)106 void grpc_iocp_init(void) {
107 g_iocp =
108 CreateIoCompletionPort(INVALID_HANDLE_VALUE, NULL, (ULONG_PTR)NULL, 0);
109 GPR_ASSERT(g_iocp);
110 }
111
grpc_iocp_kick(void)112 void grpc_iocp_kick(void) {
113 BOOL success;
114
115 gpr_atm_full_fetch_add(&g_custom_events, 1);
116 success = PostQueuedCompletionStatus(g_iocp, 0, (ULONG_PTR)&g_iocp_kick_token,
117 &g_iocp_custom_overlap);
118 GPR_ASSERT(success);
119 }
120
grpc_iocp_flush(void)121 void grpc_iocp_flush(void) {
122 grpc_core::ExecCtx exec_ctx;
123 grpc_iocp_work_status work_status;
124
125 do {
126 work_status = grpc_iocp_work(GRPC_MILLIS_INF_PAST);
127 } while (work_status == GRPC_IOCP_WORK_KICK ||
128 grpc_core::ExecCtx::Get()->Flush());
129 }
130
grpc_iocp_shutdown(void)131 void grpc_iocp_shutdown(void) {
132 grpc_core::ExecCtx exec_ctx;
133 while (gpr_atm_acq_load(&g_custom_events)) {
134 grpc_iocp_work(GRPC_MILLIS_INF_FUTURE);
135 grpc_core::ExecCtx::Get()->Flush();
136 }
137
138 GPR_ASSERT(CloseHandle(g_iocp));
139 }
140
grpc_iocp_add_socket(grpc_winsocket * socket)141 void grpc_iocp_add_socket(grpc_winsocket* socket) {
142 HANDLE ret;
143 if (socket->added_to_iocp) return;
144 ret = CreateIoCompletionPort((HANDLE)socket->socket, g_iocp,
145 (uintptr_t)socket, 0);
146 if (!ret) {
147 char* utf8_message = gpr_format_message(WSAGetLastError());
148 gpr_log(GPR_ERROR, "Unable to add socket to iocp: %s", utf8_message);
149 gpr_free(utf8_message);
150 __debugbreak();
151 abort();
152 }
153 socket->added_to_iocp = 1;
154 GPR_ASSERT(ret == g_iocp);
155 }
156
157 #endif /* GRPC_WINSOCK_SOCKET */
158