use a local PTP event queue in nikon capture to avoid checking interrupts on any event,

which causes delays.

https://github.com/gphoto/libgphoto2/issues/846

3 files changed, 53 insertions, 11 deletions

diff --git a/camlibs/ptp2/library.c b/camlibs/ptp2/library.c
index 503e54e20..4ec0990f9 100644
--- a/camlibs/ptp2/library.c
+++ b/camlibs/ptp2/library.c
@@ -4061,6 +4061,9 @@ camera_nikon_capture (Camera *camera, CameraCaptureType type, CameraFilePath *pa
 	int			back_off_wait = 0;
 	struct timeval          capture_start;
 	int			loops;
+	PTPContainer		*storedevents = NULL;
+	unsigned int		nrstoredevents = 0;
+	PTPContainer		event;
 
 
 	if (type != GP_CAPTURE_IMAGE)
@@ -4086,6 +4089,7 @@ camera_nikon_capture (Camera *camera, CameraCaptureType type, CameraFilePath *pa
                	_("Sorry, your camera does not support Nikon capture"));
 		return GP_ERROR_NOT_SUPPORTED;
 	}
+
 	if (	ptp_property_issupported(params, PTP_DPC_StillCaptureMode)	&&
 		(PTP_RC_OK == ptp_getdevicepropdesc (params, PTP_DPC_StillCaptureMode, &propdesc))) {
 		PTPDevicePropDesc       burstdesc;
@@ -4120,6 +4124,13 @@ camera_nikon_capture (Camera *camera, CameraCaptureType type, CameraFilePath *pa
 		C_PTP_REP_MSG (nikon_wait_busy(params,20,2000), _("Nikon enable liveview failed"));
 	}
 
+	/* before we start real capture, move the current hw event queue to our local queue */
+	while (ptp_get_one_event(params, &event)) {
+		GP_LOG_D ("saving event queue before capture: event.Code is %x / param %lx", event.Code, (unsigned long)event.Param1);
+		ptp_add_event_queue (&storedevents, &nrstoredevents, &event);
+	}
+
+
 	if (ptp_operation_issupported(params, PTP_OC_NIKON_InitiateCaptureRecInMedia)) {
 		/* we assume for modern cameras this event method works to avoid longer waits */
 		params->event90c7works = 1;
@@ -4156,7 +4167,12 @@ camera_nikon_capture (Camera *camera, CameraCaptureType type, CameraFilePath *pa
 	}
 
 capturetriggered:
-	C_PTP_REP (ret);
+	if (ret != PTP_RC_OK) {
+		/* store back all the queued events back to the hw event queue before returning. */
+		/* we do not do this in all error edge cases currently, only the ones that can trigger often */
+		ptp_add_events (params, &storedevents, nrstoredevents);
+		C_PTP_REP (ret);
+	}
 
 	CR (gp_port_set_timeout (camera->port, capture_timeout));
 
@@ -4166,13 +4182,9 @@ capturetriggered:
 	done = 0; tries = 100;
 	capture_start = time_now();
 	do {
-		PTPContainer	event;
-		int 		checkevt;
-
 		/* Just busy loop until the camera is ready again. */
 		/* and wait for the 0xc101 event */
 		C_PTP_REP (ptp_check_event (params));
-		checkevt = 0;
 		while (ptp_get_one_event(params, &event)) {
 			GP_LOG_D ("event.Code is %x / param %lx", event.Code, (unsigned long)event.Param1);
 			switch (event.Code) {
@@ -4191,8 +4203,7 @@ capturetriggered:
 				/* if we got one object already, put it into the queue */
 				/* e.g. for NEF+RAW capture */
 				if (newobject != 0xffff0001) {
-					ptp_add_event (params, &event);
-					checkevt = 1; /* avoid endless loop */
+					ptp_add_event_queue (&storedevents, &nrstoredevents, &event);
 					done = 3;
 					break;
 				}
@@ -4223,12 +4234,9 @@ capturetriggered:
 				break;
 			default:
 				GP_LOG_D ("UNHANDLED event.Code is %x / param %lx, DEFER", event.Code, (unsigned long)event.Param1);
-				ptp_add_event (params, &event);
-				checkevt = 1; /* avoid endless loop */
+				ptp_add_event_queue (&storedevents, &nrstoredevents, &event);
 				break;
 			}
-			if (checkevt)
-				break;
 		}
 		/* we got both capturecomplete and objectadded ... leave */
 		if (done == 3)
@@ -4241,6 +4249,10 @@ capturetriggered:
 		gp_context_idle (context);
 		/* do not drain all of the DSLRs compute time */
 	} while ((done != 3) && waiting_for_timeout (&back_off_wait, capture_start, 70*1000)); /* 70 seconds */
+
+	/* add all the queued events back to the event queue */
+	ptp_add_events (params, &storedevents, nrstoredevents);
+
 	/* Maximum image time is 30 seconds, but NR processing might take 25 seconds ... so wait longer.
 	 * see https://github.com/gphoto/libgphoto2/issues/94 */
 
diff --git a/camlibs/ptp2/ptp.c b/camlibs/ptp2/ptp.c
index 9e5df52e3..5bdce1c97 100644
--- a/camlibs/ptp2/ptp.c
+++ b/camlibs/ptp2/ptp.c
@@ -3228,11 +3228,39 @@ ptp_canon_checkevent (PTPParams* params, PTPContainer* event, int* isevent)
 }
 
 uint16_t
+ptp_add_event_queue (PTPContainer **events, unsigned int *nrevents, PTPContainer *evt)
+{
+	PTPContainer *levents;
+
+	levents = realloc(*events, sizeof(PTPContainer)*((*nrevents)+1));
+	if (!levents)
+		return PTP_RC_GeneralError;
+	*events = levents;
+	memcpy (&events[*nrevents],evt,1*sizeof(PTPContainer));
+	(*nrevents)++;
+	return PTP_RC_OK;
+}
+uint16_t
 ptp_add_event (PTPParams *params, PTPContainer *evt)
 {
+	return ptp_add_event_queue (&params->events, &params->nrofevents, evt);
+/*
 	params->events = realloc(params->events, sizeof(PTPContainer)*(params->nrofevents+1));
 	memcpy (&params->events[params->nrofevents],evt,1*sizeof(PTPContainer));
 	params->nrofevents += 1;
+
+	return PTP_RC_OK;
+*/
+}
+
+uint16_t
+ptp_add_events (PTPParams *params, PTPContainer **evt, unsigned int nrevents)
+{
+	unsigned int i;
+
+	for (i=0;i<nrevents;i++) {
+		CHECK_PTP_RC (ptp_add_event_queue (&params->events, &params->nrofevents, evt[i]));
+	}
 	return PTP_RC_OK;
 }
 
diff --git a/camlibs/ptp2/ptp.h b/camlibs/ptp2/ptp.h
index 8f0e03529..914abdede 100644
--- a/camlibs/ptp2/ptp.h
+++ b/camlibs/ptp2/ptp.h
@@ -4033,6 +4033,8 @@ uint16_t ptp_check_event (PTPParams *params);
 uint16_t ptp_check_event_queue (PTPParams *params);
 uint16_t ptp_wait_event (PTPParams *params);
 uint16_t ptp_add_event (PTPParams *params, PTPContainer *evt);
+uint16_t ptp_add_events (PTPParams *params, PTPContainer **evt, unsigned int nrevents);
+uint16_t ptp_add_event_queue (PTPContainer **events, unsigned int *nrevents, PTPContainer *evt);
 int ptp_have_event(PTPParams *params, uint16_t code);
 int ptp_get_one_event (PTPParams *params, PTPContainer *evt);
 int ptp_get_one_event_by_type(PTPParams *params, uint16_t code, PTPContainer *event);