contrib/ntp/sntp/libevent/event_iocp.c

   1 /*
   2  * Copyright (c) 2009-2012 Niels Provos, Nick Mathewson
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions
   6  * are met:
   7  * 1. Redistributions of source code must retain the above copyright
   8  *    notice, this list of conditions and the following disclaimer.
   9  * 2. Redistributions in binary form must reproduce the above copyright
  10  *    notice, this list of conditions and the following disclaimer in the
  11  *    documentation and/or other materials provided with the distribution.
  12  * 3. The name of the author may not be used to endorse or promote products
  13  *    derived from this software without specific prior written permission.
  14  *
  15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  25  */
  26 #include "evconfig-private.h"
  27
  28 #ifndef _WIN32_WINNT
  29 /* Minimum required for InitializeCriticalSectionAndSpinCount */
  30 #define _WIN32_WINNT 0x0403
  31 #endif
  32 #include <winsock2.h>
  33 #include <windows.h>
  34 #include <process.h>
  35 #include <stdio.h>
  36 #include <mswsock.h>
  37
  38 #include "event2/util.h"
  39 #include "util-internal.h"
  40 #include "iocp-internal.h"
  41 #include "log-internal.h"
  42 #include "mm-internal.h"
  43 #include "event-internal.h"
  44 #include "evthread-internal.h"
  45
  46 #define NOTIFICATION_KEY ((ULONG_PTR)-1)
  47
  48 void
  49 event_overlapped_init_(struct event_overlapped *o, iocp_callback cb)
  50 {
  51         memset(o, 0, sizeof(struct event_overlapped));
  52         o->cb = cb;
  53 }
  54
  55 static void
  56 handle_entry(OVERLAPPED *o, ULONG_PTR completion_key, DWORD nBytes, int ok)
  57 {
  58         struct event_overlapped *eo =
  59             EVUTIL_UPCAST(o, struct event_overlapped, overlapped);
  60         eo->cb(eo, completion_key, nBytes, ok);
  61 }
  62
  63 static void
  64 loop(void *port_)
  65 {
  66         struct event_iocp_port *port = port_;
  67         long ms = port->ms;
  68         HANDLE p = port->port;
  69
  70         if (ms <= 0)
  71                 ms = INFINITE;
  72
  73         while (1) {
  74                 OVERLAPPED *overlapped=NULL;
  75                 ULONG_PTR key=0;
  76                 DWORD bytes=0;
  77                 int ok = GetQueuedCompletionStatus(p, &bytes, &key,
  78                         &overlapped, ms);
  79                 EnterCriticalSection(&port->lock);
  80                 if (port->shutdown) {
  81                         if (--port->n_live_threads == 0)
  82                                 ReleaseSemaphore(port->shutdownSemaphore, 1,
  83                                                 NULL);
  84                         LeaveCriticalSection(&port->lock);
  85                         return;
  86                 }
  87                 LeaveCriticalSection(&port->lock);
  88
  89                 if (key != NOTIFICATION_KEY && overlapped)
  90                         handle_entry(overlapped, key, bytes, ok);
  91                 else if (!overlapped)
  92                         break;
  93         }
  94         event_warnx("GetQueuedCompletionStatus exited with no event.");
  95         EnterCriticalSection(&port->lock);
  96         if (--port->n_live_threads == 0)
  97                 ReleaseSemaphore(port->shutdownSemaphore, 1, NULL);
  98         LeaveCriticalSection(&port->lock);
  99 }
 100
 101 int
 102 event_iocp_port_associate_(struct event_iocp_port *port, evutil_socket_t fd,
 103     ev_uintptr_t key)
 104 {
 105         HANDLE h;
 106         h = CreateIoCompletionPort((HANDLE)fd, port->port, key, port->n_threads);
 107         if (!h)
 108                 return -1;
 109         return 0;
 110 }
 111
 112 static void *
 113 get_extension_function(SOCKET s, const GUID *which_fn)
 114 {
 115         void *ptr = NULL;
 116         DWORD bytes=0;
 117         WSAIoctl(s, SIO_GET_EXTENSION_FUNCTION_POINTER,
 118             (GUID*)which_fn, sizeof(*which_fn),
 119             &ptr, sizeof(ptr),
 120             &bytes, NULL, NULL);
 121
 122         /* No need to detect errors here: if ptr is set, then we have a good
 123            function pointer.  Otherwise, we should behave as if we had no
 124            function pointer.
 125         */
 126         return ptr;
 127 }
 128
 129 /* Mingw doesn't have these in its mswsock.h.  The values are copied from
 130    wine.h.   Perhaps if we copy them exactly, the cargo will come again.
 131 */
 132 #ifndef WSAID_ACCEPTEX
 133 #define WSAID_ACCEPTEX \
 134         {0xb5367df1,0xcbac,0x11cf,{0x95,0xca,0x00,0x80,0x5f,0x48,0xa1,0x92}}
 135 #endif
 136 #ifndef WSAID_CONNECTEX
 137 #define WSAID_CONNECTEX \
 138         {0x25a207b9,0xddf3,0x4660,{0x8e,0xe9,0x76,0xe5,0x8c,0x74,0x06,0x3e}}
 139 #endif
 140 #ifndef WSAID_GETACCEPTEXSOCKADDRS
 141 #define WSAID_GETACCEPTEXSOCKADDRS \
 142         {0xb5367df2,0xcbac,0x11cf,{0x95,0xca,0x00,0x80,0x5f,0x48,0xa1,0x92}}
 143 #endif
 144
 145 static int extension_fns_initialized = 0;
 146
 147 static void
 148 init_extension_functions(struct win32_extension_fns *ext)
 149 {
 150         const GUID acceptex = WSAID_ACCEPTEX;
 151         const GUID connectex = WSAID_CONNECTEX;
 152         const GUID getacceptexsockaddrs = WSAID_GETACCEPTEXSOCKADDRS;
 153         SOCKET s = socket(AF_INET, SOCK_STREAM, 0);
 154         if (s == INVALID_SOCKET)
 155                 return;
 156         ext->AcceptEx = get_extension_function(s, &acceptex);
 157         ext->ConnectEx = get_extension_function(s, &connectex);
 158         ext->GetAcceptExSockaddrs = get_extension_function(s,
 159             &getacceptexsockaddrs);
 160         closesocket(s);
 161
 162         extension_fns_initialized = 1;
 163 }
 164
 165 static struct win32_extension_fns the_extension_fns;
 166
 167 const struct win32_extension_fns *
 168 event_get_win32_extension_fns_(void)
 169 {
 170         return &the_extension_fns;
 171 }
 172
 173 #define N_CPUS_DEFAULT 2
 174
 175 struct event_iocp_port *
 176 event_iocp_port_launch_(int n_cpus)
 177 {
 178         struct event_iocp_port *port;
 179         int i;
 180
 181         if (!extension_fns_initialized)
 182                 init_extension_functions(&the_extension_fns);
 183
 184         if (!(port = mm_calloc(1, sizeof(struct event_iocp_port))))
 185                 return NULL;
 186
 187         if (n_cpus <= 0)
 188                 n_cpus = N_CPUS_DEFAULT;
 189         port->n_threads = n_cpus * 2;
 190         port->threads = mm_calloc(port->n_threads, sizeof(HANDLE));
 191         if (!port->threads)
 192                 goto err;
 193
 194         port->port = CreateIoCompletionPort(INVALID_HANDLE_VALUE, NULL, 0,
 195                         n_cpus);
 196         port->ms = -1;
 197         if (!port->port)
 198                 goto err;
 199
 200         port->shutdownSemaphore = CreateSemaphore(NULL, 0, 1, NULL);
 201         if (!port->shutdownSemaphore)
 202                 goto err;
 203
 204         for (i=0; i<port->n_threads; ++i) {
 205                 ev_uintptr_t th = _beginthread(loop, 0, port);
 206                 if (th == (ev_uintptr_t)-1)
 207                         goto err;
 208                 port->threads[i] = (HANDLE)th;
 209                 ++port->n_live_threads;
 210         }
 211
 212         InitializeCriticalSectionAndSpinCount(&port->lock, 1000);
 213
 214         return port;
 215 err:
 216         if (port->port)
 217                 CloseHandle(port->port);
 218         if (port->threads)
 219                 mm_free(port->threads);
 220         if (port->shutdownSemaphore)
 221                 CloseHandle(port->shutdownSemaphore);
 222         mm_free(port);
 223         return NULL;
 224 }
 225
 226 static void
 227 event_iocp_port_unlock_and_free_(struct event_iocp_port *port)
 228 {
 229         DeleteCriticalSection(&port->lock);
 230         CloseHandle(port->port);
 231         CloseHandle(port->shutdownSemaphore);
 232         mm_free(port->threads);
 233         mm_free(port);
 234 }
 235
 236 static int
 237 event_iocp_notify_all(struct event_iocp_port *port)
 238 {
 239         int i, r, ok=1;
 240         for (i=0; i<port->n_threads; ++i) {
 241                 r = PostQueuedCompletionStatus(port->port, 0, NOTIFICATION_KEY,
 242                     NULL);
 243                 if (!r)
 244                         ok = 0;
 245         }
 246         return ok ? 0 : -1;
 247 }
 248
 249 int
 250 event_iocp_shutdown_(struct event_iocp_port *port, long waitMsec)
 251 {
 252         DWORD ms = INFINITE;
 253         int n;
 254
 255         EnterCriticalSection(&port->lock);
 256         port->shutdown = 1;
 257         LeaveCriticalSection(&port->lock);
 258         event_iocp_notify_all(port);
 259
 260         if (waitMsec >= 0)
 261                 ms = waitMsec;
 262
 263         WaitForSingleObject(port->shutdownSemaphore, ms);
 264         EnterCriticalSection(&port->lock);
 265         n = port->n_live_threads;
 266         LeaveCriticalSection(&port->lock);
 267         if (n == 0) {
 268                 event_iocp_port_unlock_and_free_(port);
 269                 return 0;
 270         } else {
 271                 return -1;
 272         }
 273 }
 274
 275 int
 276 event_iocp_activate_overlapped_(
 277     struct event_iocp_port *port, struct event_overlapped *o,
 278     ev_uintptr_t key, ev_uint32_t n)
 279 {
 280         BOOL r;
 281
 282         r = PostQueuedCompletionStatus(port->port, n, key, &o->overlapped);
 283         return (r==0) ? -1 : 0;
 284 }
 285
 286 struct event_iocp_port *
 287 event_base_get_iocp_(struct event_base *base)
 288 {
 289 #ifdef _WIN32
 290         return base->iocp;
 291 #else
 292         return NULL;
 293 #endif
 294 }