This emulates Win32 manual-reset events using futexes or conditional
variables.  Typical ways to use them are with multi-producer,
single-consumer data structures, to test for a complex condition whose
elements come from different threads:
    for (;;) {
        qemu_event_reset(ev);
        ... test complex condition ...
        if (condition is true) {
            break;
        }
        qemu_event_wait(ev);
    }
Or more efficiently (but with some duplication):
    ... evaluate condition ...
    while (!condition) {
        qemu_event_reset(ev);
        ... evaluate condition ...
        if (!condition) {
            qemu_event_wait(ev);
            ... evaluate condition ...
        }
    }
QemuEvent provides a very fast userspace path in the common case when
no other thread is waiting, or the event is not changing state.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
		
	
			
		
			
				
	
	
		
			34 lines
		
	
	
		
			540 B
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			34 lines
		
	
	
		
			540 B
		
	
	
	
		
			C
		
	
	
	
	
	
#ifndef __QEMU_THREAD_WIN32_H
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#define __QEMU_THREAD_WIN32_H 1
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#include "windows.h"
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struct QemuMutex {
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    CRITICAL_SECTION lock;
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    LONG owner;
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};
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struct QemuCond {
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    LONG waiters, target;
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    HANDLE sema;
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    HANDLE continue_event;
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};
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struct QemuSemaphore {
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    HANDLE sema;
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};
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struct QemuEvent {
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    HANDLE event;
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};
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typedef struct QemuThreadData QemuThreadData;
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struct QemuThread {
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    QemuThreadData *data;
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    unsigned tid;
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};
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/* Only valid for joinable threads.  */
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HANDLE qemu_thread_get_handle(QemuThread *thread);
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#endif
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