cam: Rename Capture to CameraSession

Rename the Capture class to CameraSession, to prepare for multi-camera
support that will gather more camera-related operations than capture in
that class.

While at it, remove an unneeded blank line.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>

src/cam/camera_session.cpp

@@ -0,0 +1,240 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (C) 2019, Google Inc.
+ *
+ * camera_session.cpp - Camera capture session
+ */
+
+#include <iomanip>
+#include <iostream>
+#include <limits.h>
+#include <sstream>
+
+#include <libcamera/control_ids.h>
+
+#include "camera_session.h"
+#include "main.h"
+
+using namespace libcamera;
+
+CameraSession::CameraSession(std::shared_ptr<Camera> camera,
+			     CameraConfiguration *config, EventLoop *loop)
+	: camera_(camera), config_(config), writer_(nullptr), last_(0), loop_(loop),
+	  queueCount_(0), captureCount_(0), captureLimit_(0),
+	  printMetadata_(false)
+{
+}
+
+int CameraSession::run(const OptionsParser::Options &options)
+{
+	int ret;
+
+	queueCount_ = 0;
+	captureCount_ = 0;
+	captureLimit_ = options[OptCapture].toInteger();
+	printMetadata_ = options.isSet(OptMetadata);
+
+	if (!camera_) {
+		std::cout << "Can't capture without a camera" << std::endl;
+		return -ENODEV;
+	}
+
+	ret = camera_->configure(config_);
+	if (ret < 0) {
+		std::cout << "Failed to configure camera" << std::endl;
+		return ret;
+	}
+
+	streamName_.clear();
+	for (unsigned int index = 0; index < config_->size(); ++index) {
+		StreamConfiguration &cfg = config_->at(index);
+		streamName_[cfg.stream()] = "stream" + std::to_string(index);
+	}
+
+	camera_->requestCompleted.connect(this, &CameraSession::requestComplete);
+
+	if (options.isSet(OptFile)) {
+		if (!options[OptFile].toString().empty())
+			writer_ = new BufferWriter(options[OptFile]);
+		else
+			writer_ = new BufferWriter();
+	}
+
+	FrameBufferAllocator *allocator = new FrameBufferAllocator(camera_);
+
+	ret = capture(allocator);
+
+	if (options.isSet(OptFile)) {
+		delete writer_;
+		writer_ = nullptr;
+	}
+
+	requests_.clear();
+
+	delete allocator;
+
+	return ret;
+}
+
+int CameraSession::capture(FrameBufferAllocator *allocator)
+{
+	int ret;
+
+	/* Identify the stream with the least number of buffers. */
+	unsigned int nbuffers = UINT_MAX;
+	for (StreamConfiguration &cfg : *config_) {
+		ret = allocator->allocate(cfg.stream());
+		if (ret < 0) {
+			std::cerr << "Can't allocate buffers" << std::endl;
+			return -ENOMEM;
+		}
+
+		unsigned int allocated = allocator->buffers(cfg.stream()).size();
+		nbuffers = std::min(nbuffers, allocated);
+	}
+
+	/*
+	 * TODO: make cam tool smarter to support still capture by for
+	 * example pushing a button. For now run all streams all the time.
+	 */
+
+	for (unsigned int i = 0; i < nbuffers; i++) {
+		std::unique_ptr<Request> request = camera_->createRequest();
+		if (!request) {
+			std::cerr << "Can't create request" << std::endl;
+			return -ENOMEM;
+		}
+
+		for (StreamConfiguration &cfg : *config_) {
+			Stream *stream = cfg.stream();
+			const std::vector<std::unique_ptr<FrameBuffer>> &buffers =
+				allocator->buffers(stream);
+			const std::unique_ptr<FrameBuffer> &buffer = buffers[i];
+
+			ret = request->addBuffer(stream, buffer.get());
+			if (ret < 0) {
+				std::cerr << "Can't set buffer for request"
+					  << std::endl;
+				return ret;
+			}
+
+			if (writer_)
+				writer_->mapBuffer(buffer.get());
+		}
+
+		requests_.push_back(std::move(request));
+	}
+
+	ret = camera_->start();
+	if (ret) {
+		std::cout << "Failed to start capture" << std::endl;
+		return ret;
+	}
+
+	for (std::unique_ptr<Request> &request : requests_) {
+		ret = queueRequest(request.get());
+		if (ret < 0) {
+			std::cerr << "Can't queue request" << std::endl;
+			camera_->stop();
+			return ret;
+		}
+	}
+
+	if (captureLimit_)
+		std::cout << "Capture " << captureLimit_ << " frames" << std::endl;
+	else
+		std::cout << "Capture until user interrupts by SIGINT" << std::endl;
+
+	ret = loop_->exec();
+	if (ret)
+		std::cout << "Failed to run capture loop" << std::endl;
+
+	ret = camera_->stop();
+	if (ret)
+		std::cout << "Failed to stop capture" << std::endl;
+
+	return ret;
+}
+
+int CameraSession::queueRequest(Request *request)
+{
+	if (captureLimit_ && queueCount_ >= captureLimit_)
+		return 0;
+
+	queueCount_++;
+
+	return camera_->queueRequest(request);
+}
+
+void CameraSession::requestComplete(Request *request)
+{
+	if (request->status() == Request::RequestCancelled)
+		return;
+
+	/*
+	 * Defer processing of the completed request to the event loop, to avoid
+	 * blocking the camera manager thread.
+	 */
+	loop_->callLater([=]() { processRequest(request); });
+}
+
+void CameraSession::processRequest(Request *request)
+{
+	const Request::BufferMap &buffers = request->buffers();
+
+	/*
+	 * Compute the frame rate. The timestamp is arbitrarily retrieved from
+	 * the first buffer, as all buffers should have matching timestamps.
+	 */
+	uint64_t ts = buffers.begin()->second->metadata().timestamp;
+	double fps = ts - last_;
+	fps = last_ != 0 && fps ? 1000000000.0 / fps : 0.0;
+	last_ = ts;
+
+	std::stringstream info;
+	info << ts / 1000000000 << "."
+	     << std::setw(6) << std::setfill('0') << ts / 1000 % 1000000
+	     << " (" << std::fixed << std::setprecision(2) << fps << " fps)";
+
+	for (auto it = buffers.begin(); it != buffers.end(); ++it) {
+		const Stream *stream = it->first;
+		FrameBuffer *buffer = it->second;
+		const std::string &name = streamName_[stream];
+
+		const FrameMetadata &metadata = buffer->metadata();
+
+		info << " " << name
+		     << " seq: " << std::setw(6) << std::setfill('0') << metadata.sequence
+		     << " bytesused: ";
+
+		unsigned int nplane = 0;
+		for (const FrameMetadata::Plane &plane : metadata.planes) {
+			info << plane.bytesused;
+			if (++nplane < metadata.planes.size())
+				info << "/";
+		}
+
+		if (writer_)
+			writer_->write(buffer, name);
+	}
+
+	std::cout << info.str() << std::endl;
+
+	if (printMetadata_) {
+		const ControlList &requestMetadata = request->metadata();
+		for (const auto &ctrl : requestMetadata) {
+			const ControlId *id = controls::controls.at(ctrl.first);
+			std::cout << "\t" << id->name() << " = "
+				  << ctrl.second.toString() << std::endl;
+		}
+	}
+
+	captureCount_++;
+	if (captureLimit_ && captureCount_ >= captureLimit_) {
+		loop_->exit(0);
+		return;
+	}
+
+	request->reuse(Request::ReuseBuffers);
+	queueRequest(request);
+}