cam: Use script parser to set controls

Add a "--script" option to the cam test application to allow specify a
capture script to be used to drive the capture session. Add to the
CameraSession class a script parser instance, created conditionally to
the OptCaptureScript option.

If the script parser has been created, use it at queueRequest time to
retrieve the list of controls that has to be associated with a Request,
and populate Request::controls() with it before queueing it to the
Camera.

Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

src/cam/camera_session.cpp

@@ -14,6 +14,7 @@
 #include <libcamera/property_ids.h>
 
 #include "camera_session.h"
+#include "capture_script.h"
 #include "event_loop.h"
 #include "file_sink.h"
 #ifdef HAVE_KMS
@@ -91,6 +92,16 @@ CameraSession::CameraSession(CameraManager *cm,
 	}
 #endif
 
+	if (options_.isSet(OptCaptureScript)) {
+		std::string scriptName = options_[OptCaptureScript].toString();
+		script_ = std::make_unique<CaptureScript>(camera_, scriptName);
+		if (!script_->valid()) {
+			std::cerr << "Invalid capture script '" << scriptName
+				  << "'" << std::endl;
+			return;
+		}
+	}
+
 	switch (config->validate()) {
 	case CameraConfiguration::Valid:
 		break;
@@ -322,6 +333,9 @@ int CameraSession::queueRequest(Request *request)
 	if (captureLimit_ && queueCount_ >= captureLimit_)
 		return 0;
 
+	if (script_)
+		request->controls() = script_->frameControls(queueCount_);
+
 	queueCount_++;
 
 	return camera_->queueRequest(request);

src/cam/camera_session.h

@@ -23,6 +23,7 @@
 
 #include "options.h"
 
+class CaptureScript;
 class FrameSink;
 
 class CameraSession
@@ -60,6 +61,8 @@ private:
 	std::shared_ptr<libcamera::Camera> camera_;
 	std::unique_ptr<libcamera::CameraConfiguration> config_;
 
+	std::unique_ptr<CaptureScript> script_;
+
 	std::map<const libcamera::Stream *, std::string> streamNames_;
 	std::unique_ptr<FrameSink> sink_;
 	unsigned int cameraIndex_;

src/cam/main.cpp

@@ -158,6 +158,10 @@ int CamApp::parseOptions(int argc, char *argv[])
 			 "Print the metadata for completed requests",
 			 "metadata", ArgumentNone, nullptr, false,
 			 OptCamera);
+	parser.addOption(OptCaptureScript, OptionString,
+			 "Load a capture session configuration script from a file",
+			 "script", ArgumentRequired, "script", false,
+			 OptCamera);
 
 	options_ = parser.parse(argc, argv);
 	if (!options_.valid())

src/cam/main.h

@@ -21,4 +21,5 @@ enum {
 	OptListControls = 256,
 	OptStrictFormats = 257,
 	OptMetadata = 258,
+	OptCaptureScript = 259,
 };