cam: capture_script: Introduce 'loop' property

Add support to the capture script for properties that control the script
execution. Script properties are specified in the 'properties' section
before the actual list of controls specified in the 'frames' section.

Define a first 'loop' property that allows repeating the frame list
periodically. All the frame ids in the 'frames' section shall be smaller
than the loop control.

Modify the capture script example to show usage of the 'loop' property
and better document the frames list while at it.

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

1 files changed, 77 insertions, 3 deletions

diff --git a/src/cam/capture_script.cpp b/src/cam/capture_script.cpp
index 5e85b3ca..5a27361c 100644
--- a/src/cam/capture_script.cpp
+++ b/src/cam/capture_script.cpp
@@ -15,7 +15,7 @@ using namespace libcamera;
 
 CaptureScript::CaptureScript(std::shared_ptr<Camera> camera,
 			     const std::string &fileName)
-	: camera_(camera), valid_(false)
+	: camera_(camera), loop_(0), valid_(false)
 {
 	FILE *fh = fopen(fileName.c_str(), "r");
 	if (!fh) {
@@ -44,8 +44,13 @@ CaptureScript::CaptureScript(std::shared_ptr<Camera> camera,
 const ControlList &CaptureScript::frameControls(unsigned int frame)
 {
 	static ControlList controls{};
+	unsigned int idx = frame;
 
-	auto it = frameControls_.find(frame);
+	/* If we loop, repeat the controls every 'loop_' frames. */
+	if (loop_)
+		idx = frame % loop_;
+
+	auto it = frameControls_.find(idx);
 	if (it == frameControls_.end())
 		return controls;
 
@@ -149,7 +154,11 @@ int CaptureScript::parseScript(FILE *script)
 
 		std::string section = eventScalarValue(event);
 
-		if (section == "frames") {
+		if (section == "properties") {
+			ret = parseProperties();
+			if (ret)
+				return ret;
+		} else if (section == "frames") {
 			ret = parseFrames();
 			if (ret)
 				return ret;
@@ -161,6 +170,65 @@ int CaptureScript::parseScript(FILE *script)
 	}
 }
 
+int CaptureScript::parseProperty()
+{
+	EventPtr event = nextEvent(YAML_MAPPING_START_EVENT);
+	if (!event)
+		return -EINVAL;
+
+	std::string prop = parseScalar();
+	if (prop.empty())
+		return -EINVAL;
+
+	if (prop == "loop") {
+		event = nextEvent();
+		if (!event)
+			return -EINVAL;
+
+		std::string value = eventScalarValue(event);
+		if (value.empty())
+			return -EINVAL;
+
+		loop_ = atoi(value.c_str());
+		if (!loop_) {
+			std::cerr << "Invalid loop limit '" << loop_ << "'"
+				  << std::endl;
+			return -EINVAL;
+		}
+	} else {
+		std::cerr << "Unsupported property '" << prop << "'" << std::endl;
+		return -EINVAL;
+	}
+
+	event = nextEvent(YAML_MAPPING_END_EVENT);
+	if (!event)
+		return -EINVAL;
+
+	return 0;
+}
+
+int CaptureScript::parseProperties()
+{
+	EventPtr event = nextEvent(YAML_SEQUENCE_START_EVENT);
+	if (!event)
+		return -EINVAL;
+
+	while (1) {
+		if (event->type == YAML_SEQUENCE_END_EVENT)
+			return 0;
+
+		int ret = parseProperty();
+		if (ret)
+			return ret;
+
+		event = nextEvent();
+		if (!event)
+			return -EINVAL;
+	}
+
+	return 0;
+}
+
 int CaptureScript::parseFrames()
 {
 	EventPtr event = nextEvent(YAML_SEQUENCE_START_EVENT);
@@ -191,6 +259,12 @@ int CaptureScript::parseFrame(EventPtr event)
 		return -EINVAL;
 
 	unsigned int frameId = atoi(key.c_str());
+	if (loop_ && frameId >= loop_) {
+		std::cerr
+			<< "Frame id (" << frameId << ") shall be smaller than"
+			<< "loop limit (" << loop_ << ")" << std::endl;
+		return -EINVAL;
+	}
 
 	event = nextEvent(YAML_MAPPING_START_EVENT);
 	if (!event)