[libcamera-devel] [PATCH v2 10/12] libcamera: camera_manager: add CameraManager class
Niklas Söderlund
niklas.soderlund at ragnatech.se
Sat Dec 29 04:28:53 CET 2018
Provide a CameraManager class which will handle listing, instancing,
destruction and lifetime management of cameras.
Signed-off-by: Niklas Söderlund <niklas.soderlund at ragnatech.se>
---
include/libcamera/camera_manager.h | 38 +++++++
include/libcamera/libcamera.h | 1 +
include/libcamera/meson.build | 1 +
src/libcamera/camera_manager.cpp | 166 +++++++++++++++++++++++++++++
src/libcamera/meson.build | 1 +
5 files changed, 207 insertions(+)
create mode 100644 include/libcamera/camera_manager.h
create mode 100644 src/libcamera/camera_manager.cpp
diff --git a/include/libcamera/camera_manager.h b/include/libcamera/camera_manager.h
new file mode 100644
index 0000000000000000..9d032d71c4c0841a
--- /dev/null
+++ b/include/libcamera/camera_manager.h
@@ -0,0 +1,38 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * Copyright (C) 2018, Google Inc.
+ *
+ * camera_manager.h - Camera management
+ */
+#ifndef __LIBCAMERA_CAMERA_MANAGER_H__
+#define __LIBCAMERA_CAMERA_MANAGER_H__
+
+#include <vector>
+#include <string>
+
+namespace libcamera {
+
+class Camera;
+class DeviceEnumerator;
+class PipelineHandler;
+
+class CameraManager
+{
+public:
+ CameraManager();
+
+ int start();
+ void stop();
+
+ std::vector<std::string> list() const;
+ Camera *get(const std::string &name);
+ void put(Camera *camera);
+
+private:
+ DeviceEnumerator *enumerator_;
+ std::vector<PipelineHandler *> pipes_;
+};
+
+} /* namespace libcamera */
+
+#endif /* __LIBCAMERA_CAMERA_MANAGER_H__ */
diff --git a/include/libcamera/libcamera.h b/include/libcamera/libcamera.h
index 44c094d92feed5ba..32fb1ff741a7b97a 100644
--- a/include/libcamera/libcamera.h
+++ b/include/libcamera/libcamera.h
@@ -8,6 +8,7 @@
#define __LIBCAMERA_LIBCAMERA_H__
#include <libcamera/camera.h>
+#include <libcamera/camera_manager.h>
namespace libcamera {
diff --git a/include/libcamera/meson.build b/include/libcamera/meson.build
index 9b266ad926681db9..3e04557d66b1a8f4 100644
--- a/include/libcamera/meson.build
+++ b/include/libcamera/meson.build
@@ -1,5 +1,6 @@
libcamera_api = files([
'camera.h',
+ 'camera_manager.h',
'libcamera.h',
])
diff --git a/src/libcamera/camera_manager.cpp b/src/libcamera/camera_manager.cpp
new file mode 100644
index 0000000000000000..1160381b72a08850
--- /dev/null
+++ b/src/libcamera/camera_manager.cpp
@@ -0,0 +1,166 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * Copyright (C) 2018, Google Inc.
+ *
+ * camera_manager.h - Camera management
+ */
+
+#include <libcamera/camera_manager.h>
+
+#include "device_enumerator.h"
+#include "pipeline_handler.h"
+
+/**
+ * \file camera_manager.h
+ * \brief Manage all cameras handled by libcamera
+ *
+ * The responsibility of the camera manager is to control the lifetime
+ * management of objects provided by libcamera.
+ *
+ * When a user wish to interact with libcamera it creates and starts a
+ * CameraManager object. Once confirmed the camera manager is running
+ * the application can list all cameras detected by the library, get
+ * one or more of the cameras and interact with them.
+ *
+ * When the user is done with the camera it should be returned to the
+ * camera manager. Once all cameras are returned to the camera manager
+ * the user is free to stop the manager.
+ *
+ * \todo Add ability to add and remove media devices based on
+ * hot-(un)plug events coming from the device enumerator.
+ *
+ * \todo Add interface to register a notification callback to the user
+ * to be able to inform it new cameras have been hot-plugged or
+ * cameras have been removed due to hot-unplug.
+ */
+
+namespace libcamera {
+
+CameraManager::CameraManager()
+ : enumerator_(nullptr)
+{
+}
+
+/**
+ * \brief Start the camera manager
+ *
+ * Start the camera manager and enumerate all devices in the system. Once
+ * the start have been confirmed the user is free to list and otherwise
+ * interact with cameras in the system until either the camera manager
+ * is stopped or the camera is unplugged from the system.
+ *
+ * \return true on successful start false otherwise
+ */
+int CameraManager::start()
+{
+ std::vector<std::string> handlers;
+
+ if (enumerator_)
+ return -ENODEV;
+
+ enumerator_ = DeviceEnumerator::create();
+
+ if (enumerator_->enumerate())
+ return -ENODEV;
+
+ /*
+ * TODO: Try to read handlers and order from configuration
+ * file and only fallback on all handlers if there is no
+ * configuration file.
+ */
+ PipelineHandlerFactory::handlers(handlers);
+
+ for (std::string const &handler : handlers) {
+ PipelineHandler *pipe;
+
+ /*
+ * Try each pipeline handler until it exhaust
+ * all pipelines it can provide.
+ */
+ do {
+ pipe = PipelineHandlerFactory::create(handler, enumerator_);
+ if (pipe)
+ pipes_.push_back(pipe);
+ } while (pipe);
+ }
+
+ /* TODO: register hot-plug callback here */
+
+ return 0;
+}
+
+/**
+ * \brief Stop the camera manager
+ *
+ * Before stopping the camera manger the caller is responsible for making
+ * sure all cameras provided by the manager are returned to the manager.
+ *
+ * After the manager has been stopped no resource provided by the camera
+ * manager should be consider valid or functional even if they for one
+ * reason or another have yet to be deleted.
+ */
+void CameraManager::stop()
+{
+ /* TODO: unregister hot-plug callback here */
+
+ for (PipelineHandler *pipe : pipes_)
+ delete pipe;
+
+ pipes_.clear();
+
+ if (enumerator_)
+ delete enumerator_;
+
+ enumerator_ = nullptr;
+}
+
+/**
+ * \brief List all detected cameras
+ *
+ * Before calling this function the caller is responsible to make sure
+ * the camera manger is running.
+ *
+ * \return List of names for all detected cameras
+ */
+std::vector<std::string> CameraManager::list() const
+{
+ std::vector<std::string> list;
+
+ for (PipelineHandler *pipe : pipes_) {
+ for (unsigned int i = 0; i < pipe->count(); i++) {
+ Camera *cam = pipe->camera(i);
+ list.push_back(cam->name());
+ }
+ }
+
+ return list;
+}
+
+/**
+ * \brief Get a camera based on name
+ *
+ * \param[in] name Name of camera to get
+ *
+ * Before calling this function the caller is responsible to make sure
+ * the camera manger is running. A camera fetched this way should be
+ * release by the user with the put() method of the Camera object once
+ * it's done using the camera.
+ *
+ * \return Pointer to Camera object or nullptr if camera not found
+ */
+Camera *CameraManager::get(const std::string &name)
+{
+ for (PipelineHandler *pipe : pipes_) {
+ for (unsigned int i = 0; i < pipe->count(); i++) {
+ Camera *cam = pipe->camera(i);
+ if (cam->name() == name) {
+ cam->get();
+ return cam;
+ }
+ }
+ }
+
+ return nullptr;
+}
+
+} /* namespace libcamera */
diff --git a/src/libcamera/meson.build b/src/libcamera/meson.build
index 0db648dd3e37156e..a8cb3fdc22784334 100644
--- a/src/libcamera/meson.build
+++ b/src/libcamera/meson.build
@@ -1,5 +1,6 @@
libcamera_sources = files([
'camera.cpp',
+ 'camera_manager.cpp',
'device_enumerator.cpp',
'log.cpp',
'main.cpp',
--
2.20.1
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