Fix polling transfer restart after InterruptStop #119
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Fix the regression introduced in the "Fix InterruptStop if called before InterruptRead" commit: it should be possible to start a new polling transfer after the previous one has been stopped. This problem prevented the polling transfer from working after an SCardDisconnect call, and led to using the sleep-based polling every 400 ms. Implementation-wise, the fix is to change the "terminate" flag to be non-sticky, i.e., unset it after reading from it.
emaxx-google
commented
Oct 27, 2023
| @@ -1622,6 +1617,10 @@ void InterruptStop(int reader_index) | |||
| if (ret < 0) | |||
| DEBUG_CRITICAL2("libusb_cancel_transfer failed: %s", | |||
| libusb_error_name(ret)); | |||
| } else { | |||
| // Indicate that the next attempt to start an interrupt transfer shouldn't | |||
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The potential problem is whether it's possible that InterruptStop() is called after the corresponding InterruptRead() already exited; in that case we'll incorrectly abort the next polling transfer later.
If that's possible indeed, I'm not 100% sure what should be the proper fix.
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Fix the regression introduced in the "Fix InterruptStop if called before InterruptRead" commit: it should be possible to start a new polling transfer after the previous one has been stopped.
This problem prevented the polling transfer from working after an SCardDisconnect call, and led to using the sleep-based polling every 400 ms.
Implementation-wise, the fix is to change the "terminate" flag to be non-sticky, i.e., unset it after reading from it.