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-rw-r--r--qemu-thread-win32.c359
1 files changed, 0 insertions, 359 deletions
diff --git a/qemu-thread-win32.c b/qemu-thread-win32.c
deleted file mode 100644
index 517878dcc1..0000000000
--- a/qemu-thread-win32.c
+++ /dev/null
@@ -1,359 +0,0 @@
-/*
- * Win32 implementation for mutex/cond/thread functions
- *
- * Copyright Red Hat, Inc. 2010
- *
- * Author:
- * Paolo Bonzini <pbonzini@redhat.com>
- *
- * This work is licensed under the terms of the GNU GPL, version 2 or later.
- * See the COPYING file in the top-level directory.
- *
- */
-#include "qemu-common.h"
-#include "qemu/thread.h"
-#include <process.h>
-#include <assert.h>
-#include <limits.h>
-
-static void error_exit(int err, const char *msg)
-{
- char *pstr;
-
- FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_ALLOCATE_BUFFER,
- NULL, err, 0, (LPTSTR)&pstr, 2, NULL);
- fprintf(stderr, "qemu: %s: %s\n", msg, pstr);
- LocalFree(pstr);
- abort();
-}
-
-void qemu_mutex_init(QemuMutex *mutex)
-{
- mutex->owner = 0;
- InitializeCriticalSection(&mutex->lock);
-}
-
-void qemu_mutex_destroy(QemuMutex *mutex)
-{
- assert(mutex->owner == 0);
- DeleteCriticalSection(&mutex->lock);
-}
-
-void qemu_mutex_lock(QemuMutex *mutex)
-{
- EnterCriticalSection(&mutex->lock);
-
- /* Win32 CRITICAL_SECTIONs are recursive. Assert that we're not
- * using them as such.
- */
- assert(mutex->owner == 0);
- mutex->owner = GetCurrentThreadId();
-}
-
-int qemu_mutex_trylock(QemuMutex *mutex)
-{
- int owned;
-
- owned = TryEnterCriticalSection(&mutex->lock);
- if (owned) {
- assert(mutex->owner == 0);
- mutex->owner = GetCurrentThreadId();
- }
- return !owned;
-}
-
-void qemu_mutex_unlock(QemuMutex *mutex)
-{
- assert(mutex->owner == GetCurrentThreadId());
- mutex->owner = 0;
- LeaveCriticalSection(&mutex->lock);
-}
-
-void qemu_cond_init(QemuCond *cond)
-{
- memset(cond, 0, sizeof(*cond));
-
- cond->sema = CreateSemaphore(NULL, 0, LONG_MAX, NULL);
- if (!cond->sema) {
- error_exit(GetLastError(), __func__);
- }
- cond->continue_event = CreateEvent(NULL, /* security */
- FALSE, /* auto-reset */
- FALSE, /* not signaled */
- NULL); /* name */
- if (!cond->continue_event) {
- error_exit(GetLastError(), __func__);
- }
-}
-
-void qemu_cond_destroy(QemuCond *cond)
-{
- BOOL result;
- result = CloseHandle(cond->continue_event);
- if (!result) {
- error_exit(GetLastError(), __func__);
- }
- cond->continue_event = 0;
- result = CloseHandle(cond->sema);
- if (!result) {
- error_exit(GetLastError(), __func__);
- }
- cond->sema = 0;
-}
-
-void qemu_cond_signal(QemuCond *cond)
-{
- DWORD result;
-
- /*
- * Signal only when there are waiters. cond->waiters is
- * incremented by pthread_cond_wait under the external lock,
- * so we are safe about that.
- */
- if (cond->waiters == 0) {
- return;
- }
-
- /*
- * Waiting threads decrement it outside the external lock, but
- * only if another thread is executing pthread_cond_broadcast and
- * has the mutex. So, it also cannot be decremented concurrently
- * with this particular access.
- */
- cond->target = cond->waiters - 1;
- result = SignalObjectAndWait(cond->sema, cond->continue_event,
- INFINITE, FALSE);
- if (result == WAIT_ABANDONED || result == WAIT_FAILED) {
- error_exit(GetLastError(), __func__);
- }
-}
-
-void qemu_cond_broadcast(QemuCond *cond)
-{
- BOOLEAN result;
- /*
- * As in pthread_cond_signal, access to cond->waiters and
- * cond->target is locked via the external mutex.
- */
- if (cond->waiters == 0) {
- return;
- }
-
- cond->target = 0;
- result = ReleaseSemaphore(cond->sema, cond->waiters, NULL);
- if (!result) {
- error_exit(GetLastError(), __func__);
- }
-
- /*
- * At this point all waiters continue. Each one takes its
- * slice of the semaphore. Now it's our turn to wait: Since
- * the external mutex is held, no thread can leave cond_wait,
- * yet. For this reason, we can be sure that no thread gets
- * a chance to eat *more* than one slice. OTOH, it means
- * that the last waiter must send us a wake-up.
- */
- WaitForSingleObject(cond->continue_event, INFINITE);
-}
-
-void qemu_cond_wait(QemuCond *cond, QemuMutex *mutex)
-{
- /*
- * This access is protected under the mutex.
- */
- cond->waiters++;
-
- /*
- * Unlock external mutex and wait for signal.
- * NOTE: we've held mutex locked long enough to increment
- * waiters count above, so there's no problem with
- * leaving mutex unlocked before we wait on semaphore.
- */
- qemu_mutex_unlock(mutex);
- WaitForSingleObject(cond->sema, INFINITE);
-
- /* Now waiters must rendez-vous with the signaling thread and
- * let it continue. For cond_broadcast this has heavy contention
- * and triggers thundering herd. So goes life.
- *
- * Decrease waiters count. The mutex is not taken, so we have
- * to do this atomically.
- *
- * All waiters contend for the mutex at the end of this function
- * until the signaling thread relinquishes it. To ensure
- * each waiter consumes exactly one slice of the semaphore,
- * the signaling thread stops until it is told by the last
- * waiter that it can go on.
- */
- if (InterlockedDecrement(&cond->waiters) == cond->target) {
- SetEvent(cond->continue_event);
- }
-
- qemu_mutex_lock(mutex);
-}
-
-void qemu_sem_init(QemuSemaphore *sem, int init)
-{
- /* Manual reset. */
- sem->sema = CreateSemaphore(NULL, init, LONG_MAX, NULL);
-}
-
-void qemu_sem_destroy(QemuSemaphore *sem)
-{
- CloseHandle(sem->sema);
-}
-
-void qemu_sem_post(QemuSemaphore *sem)
-{
- ReleaseSemaphore(sem->sema, 1, NULL);
-}
-
-int qemu_sem_timedwait(QemuSemaphore *sem, int ms)
-{
- int rc = WaitForSingleObject(sem->sema, ms);
- if (rc == WAIT_OBJECT_0) {
- return 0;
- }
- if (rc != WAIT_TIMEOUT) {
- error_exit(GetLastError(), __func__);
- }
- return -1;
-}
-
-void qemu_sem_wait(QemuSemaphore *sem)
-{
- if (WaitForSingleObject(sem->sema, INFINITE) != WAIT_OBJECT_0) {
- error_exit(GetLastError(), __func__);
- }
-}
-
-struct QemuThreadData {
- /* Passed to win32_start_routine. */
- void *(*start_routine)(void *);
- void *arg;
- short mode;
-
- /* Only used for joinable threads. */
- bool exited;
- void *ret;
- CRITICAL_SECTION cs;
-};
-
-static __thread QemuThreadData *qemu_thread_data;
-
-static unsigned __stdcall win32_start_routine(void *arg)
-{
- QemuThreadData *data = (QemuThreadData *) arg;
- void *(*start_routine)(void *) = data->start_routine;
- void *thread_arg = data->arg;
-
- if (data->mode == QEMU_THREAD_DETACHED) {
- g_free(data);
- data = NULL;
- }
- qemu_thread_data = data;
- qemu_thread_exit(start_routine(thread_arg));
- abort();
-}
-
-void qemu_thread_exit(void *arg)
-{
- QemuThreadData *data = qemu_thread_data;
-
- if (data) {
- assert(data->mode != QEMU_THREAD_DETACHED);
- data->ret = arg;
- EnterCriticalSection(&data->cs);
- data->exited = true;
- LeaveCriticalSection(&data->cs);
- }
- _endthreadex(0);
-}
-
-void *qemu_thread_join(QemuThread *thread)
-{
- QemuThreadData *data;
- void *ret;
- HANDLE handle;
-
- data = thread->data;
- if (!data) {
- return NULL;
- }
- /*
- * Because multiple copies of the QemuThread can exist via
- * qemu_thread_get_self, we need to store a value that cannot
- * leak there. The simplest, non racy way is to store the TID,
- * discard the handle that _beginthreadex gives back, and
- * get another copy of the handle here.
- */
- handle = qemu_thread_get_handle(thread);
- if (handle) {
- WaitForSingleObject(handle, INFINITE);
- CloseHandle(handle);
- }
- ret = data->ret;
- assert(data->mode != QEMU_THREAD_DETACHED);
- DeleteCriticalSection(&data->cs);
- g_free(data);
- return ret;
-}
-
-void qemu_thread_create(QemuThread *thread,
- void *(*start_routine)(void *),
- void *arg, int mode)
-{
- HANDLE hThread;
- struct QemuThreadData *data;
-
- data = g_malloc(sizeof *data);
- data->start_routine = start_routine;
- data->arg = arg;
- data->mode = mode;
- data->exited = false;
-
- if (data->mode != QEMU_THREAD_DETACHED) {
- InitializeCriticalSection(&data->cs);
- }
-
- hThread = (HANDLE) _beginthreadex(NULL, 0, win32_start_routine,
- data, 0, &thread->tid);
- if (!hThread) {
- error_exit(GetLastError(), __func__);
- }
- CloseHandle(hThread);
- thread->data = (mode == QEMU_THREAD_DETACHED) ? NULL : data;
-}
-
-void qemu_thread_get_self(QemuThread *thread)
-{
- thread->data = qemu_thread_data;
- thread->tid = GetCurrentThreadId();
-}
-
-HANDLE qemu_thread_get_handle(QemuThread *thread)
-{
- QemuThreadData *data;
- HANDLE handle;
-
- data = thread->data;
- if (!data) {
- return NULL;
- }
-
- assert(data->mode != QEMU_THREAD_DETACHED);
- EnterCriticalSection(&data->cs);
- if (!data->exited) {
- handle = OpenThread(SYNCHRONIZE | THREAD_SUSPEND_RESUME, FALSE,
- thread->tid);
- } else {
- handle = NULL;
- }
- LeaveCriticalSection(&data->cs);
- return handle;
-}
-
-bool qemu_thread_is_self(QemuThread *thread)
-{
- return GetCurrentThreadId() == thread->tid;
-}
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