]> arthur.barton.de Git - netatalk.git/blobdiff - libevent/evthread_win32.c
New service controller process netatalk
[netatalk.git] / libevent / evthread_win32.c
diff --git a/libevent/evthread_win32.c b/libevent/evthread_win32.c
new file mode 100644 (file)
index 0000000..2389d72
--- /dev/null
@@ -0,0 +1,339 @@
+/*
+ * Copyright 2009-2012 Niels Provos and Nick Mathewson
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. 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.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
+ */
+#include "event2/event-config.h"
+
+#ifdef WIN32
+#ifndef _WIN32_WINNT
+/* Minimum required for InitializeCriticalSectionAndSpinCount */
+#define _WIN32_WINNT 0x0403
+#endif
+#include <winsock2.h>
+#define WIN32_LEAN_AND_MEAN
+#include <windows.h>
+#undef WIN32_LEAN_AND_MEAN
+#include <sys/locking.h>
+#endif
+
+struct event_base;
+#include "event2/thread.h"
+
+#include "mm-internal.h"
+#include "evthread-internal.h"
+
+#define SPIN_COUNT 2000
+
+static void *
+evthread_win32_lock_create(unsigned locktype)
+{
+       CRITICAL_SECTION *lock = mm_malloc(sizeof(CRITICAL_SECTION));
+       if (!lock)
+               return NULL;
+       if (InitializeCriticalSectionAndSpinCount(lock, SPIN_COUNT) == 0) {
+               mm_free(lock);
+               return NULL;
+       }
+       return lock;
+}
+
+static void
+evthread_win32_lock_free(void *_lock, unsigned locktype)
+{
+       CRITICAL_SECTION *lock = _lock;
+       DeleteCriticalSection(lock);
+       mm_free(lock);
+}
+
+static int
+evthread_win32_lock(unsigned mode, void *_lock)
+{
+       CRITICAL_SECTION *lock = _lock;
+       if ((mode & EVTHREAD_TRY)) {
+               return ! TryEnterCriticalSection(lock);
+       } else {
+               EnterCriticalSection(lock);
+               return 0;
+       }
+}
+
+static int
+evthread_win32_unlock(unsigned mode, void *_lock)
+{
+       CRITICAL_SECTION *lock = _lock;
+       LeaveCriticalSection(lock);
+       return 0;
+}
+
+static unsigned long
+evthread_win32_get_id(void)
+{
+       return (unsigned long) GetCurrentThreadId();
+}
+
+#ifdef WIN32_HAVE_CONDITION_VARIABLES
+static void WINAPI (*InitializeConditionVariable_fn)(PCONDITION_VARIABLE)
+       = NULL;
+static BOOL WINAPI (*SleepConditionVariableCS_fn)(
+       PCONDITION_VARIABLE, PCRITICAL_SECTION, DWORD) = NULL;
+static void WINAPI (*WakeAllConditionVariable_fn)(PCONDITION_VARIABLE) = NULL;
+static void WINAPI (*WakeConditionVariable_fn)(PCONDITION_VARIABLE) = NULL;
+
+static int
+evthread_win32_condvar_init(void)
+{
+       HANDLE lib;
+
+       lib = GetModuleHandle(TEXT("kernel32.dll"));
+       if (lib == NULL)
+               return 0;
+
+#define LOAD(name)                             \
+       name##_fn = GetProcAddress(lib, #name)
+       LOAD(InitializeConditionVariable);
+       LOAD(SleepConditionVariable);
+       LOAD(WakeAllConditionVariable);
+       LOAD(WakeConditionVariable);
+
+       return InitializeConditionVariable_fn && SleepConditionVariableCS_fn &&
+           WakeAllConditionVariable_fn && WakeConditionVariable_fn;
+}
+
+/* XXXX Even if we can build this, we don't necessarily want to: the functions
+ * in question didn't exist before Vista, so we'd better LoadProc them. */
+static void *
+evthread_win32_condvar_alloc(unsigned condflags)
+{
+       CONDITION_VARIABLE *cond = mm_malloc(sizeof(CONDITION_VARIABLE));
+       if (!cond)
+               return NULL;
+       InitializeConditionVariable_fn(cond);
+       return cond;
+}
+
+static void
+evthread_win32_condvar_free(void *_cond)
+{
+       CONDITION_VARIABLE *cond = _cond;
+       /* There doesn't _seem_ to be a cleaup fn here... */
+       mm_free(cond);
+}
+
+static int
+evthread_win32_condvar_signal(void *_cond, int broadcast)
+{
+       CONDITION_VARIABLE *cond = _cond;
+       if (broadcast)
+               WakeAllConditionVariable_fn(cond);
+       else
+               WakeConditionVariable_fn(cond);
+       return 0;
+}
+
+static int
+evthread_win32_condvar_wait(void *_cond, void *_lock, const struct timeval *tv)
+{
+       CONDITION_VARIABLE *cond = _cond;
+       CRITICAL_SECTION *lock = _lock;
+       DWORD ms, err;
+       BOOL result;
+
+       if (tv)
+               ms = evutil_tv_to_msec(tv);
+       else
+               ms = INFINITE;
+       result = SleepConditionVariableCS_fn(cond, lock, ms);
+       if (result) {
+               if (GetLastError() == WAIT_TIMEOUT)
+                       return 1;
+               else
+                       return -1;
+       } else {
+               return 0;
+       }
+}
+#endif
+
+struct evthread_win32_cond {
+       HANDLE event;
+
+       CRITICAL_SECTION lock;
+       int n_waiting;
+       int n_to_wake;
+       int generation;
+};
+
+static void *
+evthread_win32_cond_alloc(unsigned flags)
+{
+       struct evthread_win32_cond *cond;
+       if (!(cond = mm_malloc(sizeof(struct evthread_win32_cond))))
+               return NULL;
+       if (InitializeCriticalSectionAndSpinCount(&cond->lock, SPIN_COUNT)==0) {
+               mm_free(cond);
+               return NULL;
+       }
+       if ((cond->event = CreateEvent(NULL,TRUE,FALSE,NULL)) == NULL) {
+               DeleteCriticalSection(&cond->lock);
+               mm_free(cond);
+               return NULL;
+       }
+       cond->n_waiting = cond->n_to_wake = cond->generation = 0;
+       return cond;
+}
+
+static void
+evthread_win32_cond_free(void *_cond)
+{
+       struct evthread_win32_cond *cond = _cond;
+       DeleteCriticalSection(&cond->lock);
+       CloseHandle(cond->event);
+       mm_free(cond);
+}
+
+static int
+evthread_win32_cond_signal(void *_cond, int broadcast)
+{
+       struct evthread_win32_cond *cond = _cond;
+       EnterCriticalSection(&cond->lock);
+       if (broadcast)
+               cond->n_to_wake = cond->n_waiting;
+       else
+               ++cond->n_to_wake;
+       cond->generation++;
+       SetEvent(cond->event);
+       LeaveCriticalSection(&cond->lock);
+       return 0;
+}
+
+static int
+evthread_win32_cond_wait(void *_cond, void *_lock, const struct timeval *tv)
+{
+       struct evthread_win32_cond *cond = _cond;
+       CRITICAL_SECTION *lock = _lock;
+       int generation_at_start;
+       int waiting = 1;
+       int result = -1;
+       DWORD ms = INFINITE, ms_orig = INFINITE, startTime, endTime;
+       if (tv)
+               ms_orig = ms = evutil_tv_to_msec(tv);
+
+       EnterCriticalSection(&cond->lock);
+       ++cond->n_waiting;
+       generation_at_start = cond->generation;
+       LeaveCriticalSection(&cond->lock);
+
+       LeaveCriticalSection(lock);
+
+       startTime = GetTickCount();
+       do {
+               DWORD res;
+               res = WaitForSingleObject(cond->event, ms);
+               EnterCriticalSection(&cond->lock);
+               if (cond->n_to_wake &&
+                   cond->generation != generation_at_start) {
+                       --cond->n_to_wake;
+                       --cond->n_waiting;
+                       result = 0;
+                       waiting = 0;
+                       goto out;
+               } else if (res != WAIT_OBJECT_0) {
+                       result = (res==WAIT_TIMEOUT) ? 1 : -1;
+                       --cond->n_waiting;
+                       waiting = 0;
+                       goto out;
+               } else if (ms != INFINITE) {
+                       endTime = GetTickCount();
+                       if (startTime + ms_orig <= endTime) {
+                               result = 1; /* Timeout */
+                               --cond->n_waiting;
+                               waiting = 0;
+                               goto out;
+                       } else {
+                               ms = startTime + ms_orig - endTime;
+                       }
+               }
+               /* If we make it here, we are still waiting. */
+               if (cond->n_to_wake == 0) {
+                       /* There is nobody else who should wake up; reset
+                        * the event. */
+                       ResetEvent(cond->event);
+               }
+       out:
+               LeaveCriticalSection(&cond->lock);
+       } while (waiting);
+
+       EnterCriticalSection(lock);
+
+       EnterCriticalSection(&cond->lock);
+       if (!cond->n_waiting)
+               ResetEvent(cond->event);
+       LeaveCriticalSection(&cond->lock);
+
+       return result;
+}
+
+int
+evthread_use_windows_threads(void)
+{
+       struct evthread_lock_callbacks cbs = {
+               EVTHREAD_LOCK_API_VERSION,
+               EVTHREAD_LOCKTYPE_RECURSIVE,
+               evthread_win32_lock_create,
+               evthread_win32_lock_free,
+               evthread_win32_lock,
+               evthread_win32_unlock
+       };
+
+
+       struct evthread_condition_callbacks cond_cbs = {
+               EVTHREAD_CONDITION_API_VERSION,
+               evthread_win32_cond_alloc,
+               evthread_win32_cond_free,
+               evthread_win32_cond_signal,
+               evthread_win32_cond_wait
+       };
+#ifdef WIN32_HAVE_CONDITION_VARIABLES
+       struct evthread_condition_callbacks condvar_cbs = {
+               EVTHREAD_CONDITION_API_VERSION,
+               evthread_win32_condvar_alloc,
+               evthread_win32_condvar_free,
+               evthread_win32_condvar_signal,
+               evthread_win32_condvar_wait
+       };
+#endif
+
+       evthread_set_lock_callbacks(&cbs);
+       evthread_set_id_callback(evthread_win32_get_id);
+#ifdef WIN32_HAVE_CONDITION_VARIABLES
+       if (evthread_win32_condvar_init()) {
+               evthread_set_condition_callbacks(&condvar_cbs);
+               return 0;
+       }
+#endif
+       evthread_set_condition_callbacks(&cond_cbs);
+
+       return 0;
+}
+