| Message ID | 20221019102015.2441622-2-bmeng.cn@gmail.com |
|---|---|
| State | New |
| Headers | show |
| Series | [v4,1/3] util/main-loop: Fix maximum number of wait objects for win32 | expand |
On 19/10/22 12:20, Bin Meng wrote: > From: Bin Meng <bin.meng@windriver.com> > > Fix the logic in qemu_add_wait_object() to avoid adding the same > HANDLE twice, as the behavior is undefined when passing an array > that contains same HANDLEs to WaitForMultipleObjects() API. > > Signed-off-by: Bin Meng <bin.meng@windriver.com> > --- > > (no changes since v3) > > Changes in v3: > - new patch: avoid adding the same HANDLE twice > > include/qemu/main-loop.h | 2 ++ > util/main-loop.c | 10 ++++++++++ > 2 files changed, 12 insertions(+) Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
diff --git a/include/qemu/main-loop.h b/include/qemu/main-loop.h index aac707d073..3c9a9a982d 100644 --- a/include/qemu/main-loop.h +++ b/include/qemu/main-loop.h @@ -157,6 +157,8 @@ typedef void WaitObjectFunc(void *opaque); * in the main loop's calls to WaitForMultipleObjects. When the handle * is in a signaled state, QEMU will call @func. * + * If the same HANDLE is added twice, this function returns -1. + * * @handle: The Windows handle to be observed. * @func: A function to be called when @handle is in a signaled state. * @opaque: A pointer-size value that is passed to @func. diff --git a/util/main-loop.c b/util/main-loop.c index de38876064..10fa74c6e3 100644 --- a/util/main-loop.c +++ b/util/main-loop.c @@ -373,10 +373,20 @@ static WaitObjects wait_objects = {0}; int qemu_add_wait_object(HANDLE handle, WaitObjectFunc *func, void *opaque) { + int i; WaitObjects *w = &wait_objects; + if (w->num >= MAXIMUM_WAIT_OBJECTS) { return -1; } + + for (i = 0; i < w->num; i++) { + /* check if the same handle is added twice */ + if (w->events[i] == handle) { + return -1; + } + } + w->events[w->num] = handle; w->func[w->num] = func; w->opaque[w->num] = opaque;