[libcamera-devel] [PATCH v6 5/5] v4l2: v4l2_compat: Add V4L2 compatibility layer
Paul Elder
paul.elder at ideasonboard.com
Sat Jan 4 01:14:13 CET 2020
Add libcamera V4L2 compatibility layer.
This initial implementation supports the minimal set of V4L2 operations,
which allows getting, setting, and enumerating formats, and streaming
frames from a video device. Some data about the wrapped V4L2 video
device are hardcoded.
Add a build option named 'v4l2' and adjust the build system to
selectively compile the V4L2 compatibility layer.
For now we match the V4L2 device node to a libcamera camera based on a
devnum that a pipeline handler may optionally map to a libcamera
camera.
Signed-off-by: Paul Elder <paul.elder at ideasonboard.com>
Reviewed-by: Jacopo Mondi <jacopo at jmondi.org>
Reviewed-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
---
Changes in v6:
- use strlcpy instead of memcpy in V4L2CameraProxy
- fix fourcc conversion in V4L2CameraProxy::vidioc_try_fmt
- add aliases for __open_2 and __openat_2
- cosmetic changes and other little fixes
Changes in v5:
- cosmetic changes and little fixes
Major changes in v4:
- squash buffer state tracking in V4L2CameraProxy (from 6/6 in v3)
- separated out V4L2CameraProxy::freeBuffers() (since it was cluttering
up V4L2CameraProxy::vidioc_reqbufs)
Less major changes in v4:
- check that addresses passed to V4L2CameraProxy::munmap() have been
mmaped
- other cosmetic changes
Major changes in v3:
- V4L2CompatManager::openat() verify video node and match to camera via
devnum instead of path
- add FrameMetadata class to encapsulate portions of the libcamera
Buffer that needs to be extracted to v4l2_buffer, and to prepare for
the Buffer rework
- V4L2CameraProxy refcount for tracking dups and closes (and open)
- add V4L2CompatManager::initialized_ to deal with race of waiting on
init cv after the cv is notified
Less major changes in v3:
- change the list of pending Reqeusts (v4l2 buffers queued before
streamon) to unique pointers
- V4L2Camera::updateSizeImage() -> V4L2CameraProxy::calculateSizeImage()
- change V4L2CompatManager list of V4L2CameraProxy to unique_ptr, with
maps of fd/mmap addr to V4L2CameraProxy *
- removed cross-thread validation methods from V4L2CameraProxy
(validate[Stream|Memory]Type)
- removed hasPixelFormat() and hasSize() from V4L2CameraProxy
- moved mmap logic out of V4L2Camera and into V4L2CameraProxy
- moved nonblock logic out of V4L2Camera and into V4L2CameraProxy
- add todos
- oter cosmetic changes
Changes in v2:
- move all errno acrobatics to V4L2CameraProxy
- remove all mentions of dmabuf
- make V4L2CompatManager::getCamera return pointer rather than
shared_ptr
- match V4L2 device nodes to libcamera cameras using Camera::name()
compared to /sys/dev/char/maj:min/name (only works for UVC cameras)
- in V4L2CompatManager::getCameraIndex()
- add -fvisibility=hidden to v4l2 compat
- cache the results of V4L2CompatManager::imageSize() within V4L2Camera
(where V4L2Camera is interested)
- remove V4L2CompatManager::valid[fd|mmap], and where those methods were
used, check V4L2CompatManager::getCamera() != nullptr instead
- fixed V4L2CompatManager::drmToV4L2() mappings for DRM_FORMAT_BGR888
and DRM_FORMAT_RGB888
- other cosmetic changes
---
meson_options.txt | 5 +
src/meson.build | 4 +
src/v4l2/meson.build | 31 ++
src/v4l2/v4l2_camera.cpp | 224 +++++++++++
src/v4l2/v4l2_camera.h | 85 ++++
src/v4l2/v4l2_camera_proxy.cpp | 644 +++++++++++++++++++++++++++++++
src/v4l2/v4l2_camera_proxy.h | 81 ++++
src/v4l2/v4l2_compat.cpp | 85 ++++
src/v4l2/v4l2_compat_manager.cpp | 250 ++++++++++++
src/v4l2/v4l2_compat_manager.h | 77 ++++
10 files changed, 1486 insertions(+)
create mode 100644 src/v4l2/meson.build
create mode 100644 src/v4l2/v4l2_camera.cpp
create mode 100644 src/v4l2/v4l2_camera.h
create mode 100644 src/v4l2/v4l2_camera_proxy.cpp
create mode 100644 src/v4l2/v4l2_camera_proxy.h
create mode 100644 src/v4l2/v4l2_compat.cpp
create mode 100644 src/v4l2/v4l2_compat_manager.cpp
create mode 100644 src/v4l2/v4l2_compat_manager.h
diff --git a/meson_options.txt b/meson_options.txt
index 1a328045..79ee4de6 100644
--- a/meson_options.txt
+++ b/meson_options.txt
@@ -10,3 +10,8 @@ option('documentation',
option('test',
type : 'boolean',
description: 'Compile and include the tests')
+
+option('v4l2',
+ type : 'boolean',
+ value : false,
+ description : 'Compile the V4L2 compatibility layer')
diff --git a/src/meson.build b/src/meson.build
index 67ad20aa..5adcd61f 100644
--- a/src/meson.build
+++ b/src/meson.build
@@ -6,3 +6,7 @@ subdir('libcamera')
subdir('ipa')
subdir('cam')
subdir('qcam')
+
+if get_option('v4l2')
+ subdir('v4l2')
+endif
diff --git a/src/v4l2/meson.build b/src/v4l2/meson.build
new file mode 100644
index 00000000..14ee3594
--- /dev/null
+++ b/src/v4l2/meson.build
@@ -0,0 +1,31 @@
+v4l2_compat_sources = files([
+ 'v4l2_camera.cpp',
+ 'v4l2_camera_proxy.cpp',
+ 'v4l2_compat.cpp',
+ 'v4l2_compat_manager.cpp',
+])
+
+v4l2_compat_includes = [
+ libcamera_includes,
+ libcamera_internal_includes,
+]
+
+v4l2_compat_cpp_args = [
+ # Meson enables large file support unconditionally, which redirect file
+ # operations to 64-bit versions. This results in some symbols being
+ # renamed, for instance open() being renamed to open64(). As the V4L2
+ # adaptation wrapper needs to provide both 32-bit and 64-bit versions of
+ # file operations, disable transparent large file support.
+ '-U_FILE_OFFSET_BITS',
+ '-D_FILE_OFFSET_BITS=32',
+ '-fvisibility=hidden',
+]
+
+v4l2_compat = shared_library('v4l2-compat',
+ v4l2_compat_sources,
+ name_prefix : '',
+ install : true,
+ link_with : libcamera,
+ include_directories : v4l2_compat_includes,
+ dependencies : libcamera_deps,
+ cpp_args : v4l2_compat_cpp_args)
diff --git a/src/v4l2/v4l2_camera.cpp b/src/v4l2/v4l2_camera.cpp
new file mode 100644
index 00000000..3590730f
--- /dev/null
+++ b/src/v4l2/v4l2_camera.cpp
@@ -0,0 +1,224 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (C) 2019, Google Inc.
+ *
+ * v4l2_camera.cpp - V4L2 compatibility camera
+ */
+
+#include "v4l2_camera.h"
+
+#include <errno.h>
+
+#include "log.h"
+#include "utils.h"
+
+using namespace libcamera;
+
+LOG_DECLARE_CATEGORY(V4L2Compat);
+
+FrameMetadata::FrameMetadata(Buffer *buffer)
+ : index_(buffer->index()), bytesused_(buffer->bytesused()),
+ timestamp_(buffer->timestamp()), sequence_(buffer->sequence()),
+ status_(buffer->status())
+{
+}
+
+V4L2Camera::V4L2Camera(std::shared_ptr<Camera> camera)
+ : camera_(camera), isRunning_(false)
+{
+ camera_->requestCompleted.connect(this, &V4L2Camera::requestComplete);
+}
+
+V4L2Camera::~V4L2Camera()
+{
+ camera_->release();
+}
+
+void V4L2Camera::open(int *ret)
+{
+ /* \todo Support multiple open. */
+ if (camera_->acquire() < 0) {
+ LOG(V4L2Compat, Error) << "Failed to acquire camera";
+ *ret = -EINVAL;
+ return;
+ }
+
+ config_ = camera_->generateConfiguration({ StreamRole::Viewfinder });
+ if (!config_) {
+ camera_->release();
+ *ret = -EINVAL;
+ return;
+ }
+
+ *ret = 0;
+}
+
+void V4L2Camera::close()
+{
+ camera_->release();
+}
+
+void V4L2Camera::getStreamConfig(StreamConfiguration *streamConfig)
+{
+ *streamConfig = config_->at(0);
+}
+
+std::vector<FrameMetadata> V4L2Camera::completedBuffers()
+{
+ std::vector<FrameMetadata> v;
+
+ bufferLock_.lock();
+ for (std::unique_ptr<FrameMetadata> &metadata : completedBuffers_)
+ v.push_back(*metadata.get());
+ completedBuffers_.clear();
+ bufferLock_.unlock();
+
+ return v;
+}
+
+void V4L2Camera::requestComplete(Request *request)
+{
+ if (request->status() == Request::RequestCancelled)
+ return;
+
+ /* We only have one stream at the moment. */
+ bufferLock_.lock();
+ Buffer *buffer = request->buffers().begin()->second;
+ std::unique_ptr<FrameMetadata> metadata =
+ utils::make_unique<FrameMetadata>(buffer);
+ completedBuffers_.push_back(std::move(metadata));
+ bufferLock_.unlock();
+
+ bufferSema_.release();
+}
+
+void V4L2Camera::configure(int *ret, StreamConfiguration *streamConfigOut,
+ const Size &size, PixelFormat pixelformat,
+ unsigned int bufferCount)
+{
+ StreamConfiguration &streamConfig = config_->at(0);
+ streamConfig.size.width = size.width;
+ streamConfig.size.height = size.height;
+ streamConfig.pixelFormat = pixelformat;
+ streamConfig.bufferCount = bufferCount;
+ /* \todo memoryType (interval vs external) */
+
+ CameraConfiguration::Status validation = config_->validate();
+ if (validation == CameraConfiguration::Invalid) {
+ LOG(V4L2Compat, Debug) << "Configuration invalid";
+ *ret = -EINVAL;
+ return;
+ }
+ if (validation == CameraConfiguration::Adjusted)
+ LOG(V4L2Compat, Debug) << "Configuration adjusted";
+
+ LOG(V4L2Compat, Debug) << "Validated configuration is: "
+ << streamConfig.toString();
+
+ *ret = camera_->configure(config_.get());
+ if (*ret < 0)
+ return;
+
+ *streamConfigOut = config_->at(0);
+}
+
+void V4L2Camera::mmap(void **ret, unsigned int index)
+{
+ Stream *stream = *camera_->streams().begin();
+ *ret = stream->buffers()[index].planes()[0].mem();
+}
+
+void V4L2Camera::allocBuffers(int *ret, unsigned int count)
+{
+ *ret = camera_->allocateBuffers();
+ if (*ret == -EACCES)
+ *ret = -EBUSY;
+}
+
+void V4L2Camera::freeBuffers()
+{
+ camera_->freeBuffers();
+}
+
+void V4L2Camera::streamOn(int *ret)
+{
+ *ret = 0;
+
+ if (isRunning_)
+ return;
+
+ *ret = camera_->start();
+ if (*ret < 0) {
+ if (*ret == -EACCES)
+ *ret = -EBUSY;
+ return;
+ }
+ isRunning_ = true;
+
+ for (std::unique_ptr<Request> &req : pendingRequests_) {
+ /* \todo What should we do if this returns -EINVAL? */
+ *ret = camera_->queueRequest(req.release());
+ if (*ret < 0) {
+ if (*ret == -EACCES)
+ *ret = -EBUSY;
+ return;
+ }
+ }
+
+ pendingRequests_.clear();
+}
+
+void V4L2Camera::streamOff(int *ret)
+{
+ *ret = 0;
+
+ /* \todo Restore buffers to reqbufs state? */
+ if (!isRunning_)
+ return;
+
+ *ret = camera_->stop();
+ if (*ret < 0) {
+ if (*ret == -EACCES)
+ *ret = -EBUSY;
+ return;
+ }
+ isRunning_ = false;
+}
+
+void V4L2Camera::qbuf(int *ret, unsigned int index)
+{
+ Stream *stream = config_->at(0).stream();
+ std::unique_ptr<Buffer> buffer = stream->createBuffer(index);
+ if (!buffer) {
+ LOG(V4L2Compat, Error) << "Can't create buffer";
+ *ret = -ENOMEM;
+ return;
+ }
+
+ std::unique_ptr<Request> request =
+ std::unique_ptr<Request>(camera_->createRequest());
+ if (!request) {
+ LOG(V4L2Compat, Error) << "Can't create request";
+ *ret = -ENOMEM;
+ return;
+ }
+
+ *ret = request->addBuffer(std::move(buffer));
+ if (*ret < 0) {
+ LOG(V4L2Compat, Error) << "Can't set buffer for request";
+ *ret = -ENOMEM;
+ return;
+ }
+
+ if (!isRunning_) {
+ pendingRequests_.push_back(std::move(request));
+ return;
+ }
+
+ *ret = camera_->queueRequest(request.release());
+ if (*ret < 0) {
+ LOG(V4L2Compat, Error) << "Can't queue request";
+ if (*ret == -EACCES)
+ *ret = -EBUSY;
+ }
+}
diff --git a/src/v4l2/v4l2_camera.h b/src/v4l2/v4l2_camera.h
new file mode 100644
index 00000000..d24dbca6
--- /dev/null
+++ b/src/v4l2/v4l2_camera.h
@@ -0,0 +1,85 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (C) 2019, Google Inc.
+ *
+ * v4l2_camera.h - V4L2 compatibility camera
+ */
+
+#ifndef __V4L2_CAMERA_H__
+#define __V4L2_CAMERA_H__
+
+#include <deque>
+#include <linux/videodev2.h>
+#include <mutex>
+
+#include <libcamera/buffer.h>
+#include <libcamera/camera.h>
+
+#include "semaphore.h"
+
+using namespace libcamera;
+
+class FrameMetadata
+{
+public:
+ FrameMetadata(Buffer *buffer);
+
+ int index() const { return index_; }
+
+ unsigned int bytesused() const { return bytesused_; }
+ uint64_t timestamp() const { return timestamp_; }
+ unsigned int sequence() const { return sequence_; }
+
+ Buffer::Status status() const { return status_; }
+
+private:
+ int index_;
+
+ unsigned int bytesused_;
+ uint64_t timestamp_;
+ unsigned int sequence_;
+
+ Buffer::Status status_;
+};
+
+class V4L2Camera : public Object
+{
+public:
+ V4L2Camera(std::shared_ptr<Camera> camera);
+ ~V4L2Camera();
+
+ void open(int *ret);
+ void close();
+ void getStreamConfig(StreamConfiguration *streamConfig);
+ std::vector<FrameMetadata> completedBuffers();
+
+ void mmap(void **ret, unsigned int index);
+
+ void configure(int *ret, StreamConfiguration *streamConfigOut,
+ const Size &size, PixelFormat pixelformat,
+ unsigned int bufferCount);
+
+ void allocBuffers(int *ret, unsigned int count);
+ void freeBuffers();
+ void streamOn(int *ret);
+ void streamOff(int *ret);
+
+ void qbuf(int *ret, unsigned int index);
+
+ Semaphore bufferSema_;
+
+private:
+ void requestComplete(Request *request);
+
+ std::shared_ptr<Camera> camera_;
+ std::unique_ptr<CameraConfiguration> config_;
+
+ bool isRunning_;
+
+ std::mutex bufferLock_;
+
+ std::deque<std::unique_ptr<Request>> pendingRequests_;
+ std::deque<std::unique_ptr<FrameMetadata>> completedBuffers_;
+};
+
+#endif /* __V4L2_CAMERA_H__ */
diff --git a/src/v4l2/v4l2_camera_proxy.cpp b/src/v4l2/v4l2_camera_proxy.cpp
new file mode 100644
index 00000000..c9df7156
--- /dev/null
+++ b/src/v4l2/v4l2_camera_proxy.cpp
@@ -0,0 +1,644 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (C) 2019, Google Inc.
+ *
+ * v4l2_camera_proxy.cpp - Proxy to V4L2 compatibility camera
+ */
+
+#include "v4l2_camera_proxy.h"
+
+#include <algorithm>
+#include <errno.h>
+#include <linux/drm_fourcc.h>
+#include <linux/videodev2.h>
+#include <string.h>
+#include <sys/mman.h>
+
+#include <libcamera/camera.h>
+#include <libcamera/object.h>
+
+#include "log.h"
+#include "utils.h"
+#include "v4l2_camera.h"
+#include "v4l2_compat_manager.h"
+
+#define KERNEL_VERSION(a, b, c) (((a) << 16) + ((b) << 8) + (c))
+
+using namespace libcamera;
+
+LOG_DECLARE_CATEGORY(V4L2Compat);
+
+V4L2CameraProxy::V4L2CameraProxy(unsigned int index,
+ std::shared_ptr<Camera> camera)
+ : refcount_(0), index_(index), bufferCount_(0), currentBuf_(0),
+ vcam_(utils::make_unique<V4L2Camera>(camera))
+{
+ querycap(camera);
+}
+
+int V4L2CameraProxy::open(bool nonBlocking)
+{
+ LOG(V4L2Compat, Debug) << "Servicing open";
+
+ int ret;
+ vcam_->invokeMethod(&V4L2Camera::open, ConnectionTypeBlocking,
+ &ret);
+ if (ret < 0) {
+ errno = -ret;
+ return -1;
+ }
+
+ nonBlocking_ = nonBlocking;
+
+ vcam_->invokeMethod(&V4L2Camera::getStreamConfig,
+ ConnectionTypeBlocking, &streamConfig_);
+ setFmtFromConfig(streamConfig_);
+ sizeimage_ = calculateSizeImage(streamConfig_);
+
+ refcount_++;
+
+ return 0;
+}
+
+void V4L2CameraProxy::dup()
+{
+ refcount_++;
+}
+
+void V4L2CameraProxy::close()
+{
+ LOG(V4L2Compat, Debug) << "Servicing close";
+
+ if (--refcount_ > 0)
+ return;
+
+ vcam_->invokeMethod(&V4L2Camera::close, ConnectionTypeBlocking);
+}
+
+void *V4L2CameraProxy::mmap(size_t length, int prot, int flags, off_t offset)
+{
+ LOG(V4L2Compat, Debug) << "Servicing mmap";
+
+ /* \todo Validate prot and flags properly. */
+ if (prot != (PROT_READ | PROT_WRITE)) {
+ errno = EINVAL;
+ return MAP_FAILED;
+ }
+
+ unsigned int index = offset / sizeimage_;
+ if (index * sizeimage_ != offset || length != sizeimage_) {
+ errno = EINVAL;
+ return MAP_FAILED;
+ }
+
+ void *val;
+ vcam_->invokeMethod(&V4L2Camera::mmap, ConnectionTypeBlocking,
+ &val, index);
+
+ buffers_[index].flags |= V4L2_BUF_FLAG_MAPPED;
+ mmaps_[val] = index;
+
+ return val;
+}
+
+int V4L2CameraProxy::munmap(void *addr, size_t length)
+{
+ LOG(V4L2Compat, Debug) << "Servicing munmap";
+
+ auto iter = mmaps_.find(addr);
+ if (iter == mmaps_.end() || length != sizeimage_) {
+ errno = EINVAL;
+ return -1;
+ }
+
+ buffers_[iter->second].flags &= ~V4L2_BUF_FLAG_MAPPED;
+ mmaps_.erase(iter);
+
+ return 0;
+}
+
+bool V4L2CameraProxy::validateBufferType(uint32_t type)
+{
+ return type == V4L2_BUF_TYPE_VIDEO_CAPTURE;
+}
+
+bool V4L2CameraProxy::validateMemoryType(uint32_t memory)
+{
+ return memory == V4L2_MEMORY_MMAP;
+}
+
+void V4L2CameraProxy::setFmtFromConfig(StreamConfiguration &streamConfig)
+{
+ curV4L2Format_.fmt.pix.width = streamConfig.size.width;
+ curV4L2Format_.fmt.pix.height = streamConfig.size.height;
+ curV4L2Format_.fmt.pix.pixelformat = drmToV4L2(streamConfig.pixelFormat);
+ curV4L2Format_.fmt.pix.field = V4L2_FIELD_NONE;
+ curV4L2Format_.fmt.pix.bytesperline =
+ bplMultiplier(curV4L2Format_.fmt.pix.pixelformat) *
+ curV4L2Format_.fmt.pix.width;
+ curV4L2Format_.fmt.pix.sizeimage =
+ imageSize(curV4L2Format_.fmt.pix.pixelformat,
+ curV4L2Format_.fmt.pix.width,
+ curV4L2Format_.fmt.pix.height);
+ curV4L2Format_.fmt.pix.colorspace = V4L2_COLORSPACE_SRGB;
+}
+
+unsigned int V4L2CameraProxy::calculateSizeImage(StreamConfiguration &streamConfig)
+{
+ /*
+ * \todo Merge this method with setFmtFromConfig (need imageSize to
+ * support all libcamera formats first, or filter out MJPEG for now).
+ */
+ return imageSize(drmToV4L2(streamConfig.pixelFormat),
+ streamConfig.size.width,
+ streamConfig.size.height);
+}
+
+void V4L2CameraProxy::querycap(std::shared_ptr<Camera> camera)
+{
+ std::string driver = "libcamera";
+ std::string bus_info = driver + ":" + std::to_string(index_);
+
+ utils::strlcpy((char *)capabilities_.driver, driver.c_str(),
+ sizeof(capabilities_.driver));
+ utils::strlcpy((char *)capabilities_.card, camera->name().c_str(),
+ sizeof(capabilities_.card));
+ utils::strlcpy((char *)capabilities_.bus_info, bus_info.c_str(),
+ sizeof(capabilities_.bus_info));
+ /* \todo Put this in a header/config somewhere. */
+ capabilities_.version = KERNEL_VERSION(5, 2, 0);
+ capabilities_.device_caps = V4L2_CAP_VIDEO_CAPTURE;
+ capabilities_.capabilities = capabilities_.device_caps
+ | V4L2_CAP_DEVICE_CAPS;
+ memset(capabilities_.reserved, 0, sizeof(capabilities_.reserved));
+}
+
+void V4L2CameraProxy::updateBuffers()
+{
+ std::vector<FrameMetadata> completedBuffers = vcam_->completedBuffers();
+ for (FrameMetadata &fmd : completedBuffers) {
+ struct v4l2_buffer &buf = buffers_[fmd.index()];
+
+ switch (fmd.status()) {
+ case Buffer::Status::BufferSuccess:
+ buf.bytesused = fmd.bytesused();
+ buf.field = V4L2_FIELD_NONE;
+ buf.timestamp.tv_sec = fmd.timestamp() / 1000000000;
+ buf.timestamp.tv_usec = fmd.timestamp() % 1000000;
+ buf.sequence = fmd.sequence();
+
+ buf.flags |= V4L2_BUF_FLAG_DONE;
+ break;
+ case Buffer::Status::BufferError:
+ buf.flags |= V4L2_BUF_FLAG_ERROR;
+ break;
+ default:
+ break;
+ }
+ }
+}
+
+int V4L2CameraProxy::vidioc_querycap(struct v4l2_capability *arg)
+{
+ LOG(V4L2Compat, Debug) << "Servicing vidioc_querycap";
+
+ *arg = capabilities_;
+
+ return 0;
+}
+
+int V4L2CameraProxy::vidioc_enum_fmt(struct v4l2_fmtdesc *arg)
+{
+ LOG(V4L2Compat, Debug) << "Servicing vidioc_enum_fmt";
+
+ if (!validateBufferType(arg->type) ||
+ arg->index > streamConfig_.formats().pixelformats().size())
+ return -EINVAL;
+
+ /* \todo Add map from format to description. */
+ utils::strlcpy((char *)arg->description, "Video Format Description",
+ sizeof(arg->description));
+ arg->pixelformat = drmToV4L2(streamConfig_.formats().pixelformats()[arg->index]);
+
+ return 0;
+}
+
+int V4L2CameraProxy::vidioc_g_fmt(struct v4l2_format *arg)
+{
+ LOG(V4L2Compat, Debug) << "Servicing vidioc_g_fmt";
+
+ if (!validateBufferType(arg->type))
+ return -EINVAL;
+
+ memset(&arg->fmt, 0, sizeof(arg->fmt));
+ arg->fmt.pix = curV4L2Format_.fmt.pix;
+
+ return 0;
+}
+
+int V4L2CameraProxy::vidioc_s_fmt(struct v4l2_format *arg)
+{
+ LOG(V4L2Compat, Debug) << "Servicing vidioc_s_fmt";
+
+ int ret = vidioc_try_fmt(arg);
+ if (ret < 0)
+ return ret;
+
+ Size size(arg->fmt.pix.width, arg->fmt.pix.height);
+ vcam_->invokeMethod(&V4L2Camera::configure, ConnectionTypeBlocking,
+ &ret, &streamConfig_, size,
+ v4l2ToDrm(arg->fmt.pix.pixelformat), bufferCount_);
+ if (ret < 0)
+ return -EINVAL;
+
+ unsigned int sizeimage = calculateSizeImage(streamConfig_);
+ if (sizeimage == 0)
+ return -EINVAL;
+
+ sizeimage_ = sizeimage;
+
+ setFmtFromConfig(streamConfig_);
+
+ return 0;
+}
+
+int V4L2CameraProxy::vidioc_try_fmt(struct v4l2_format *arg)
+{
+ LOG(V4L2Compat, Debug) << "Servicing vidioc_try_fmt";
+ if (!validateBufferType(arg->type))
+ return -EINVAL;
+
+ PixelFormat format = v4l2ToDrm(arg->fmt.pix.pixelformat);
+ const std::vector<PixelFormat> &formats =
+ streamConfig_.formats().pixelformats();
+ if (std::find(formats.begin(), formats.end(), format) == formats.end())
+ format = streamConfig_.formats().pixelformats()[0];
+
+ Size size(arg->fmt.pix.width, arg->fmt.pix.height);
+ const std::vector<Size> &sizes = streamConfig_.formats().sizes(format);
+ if (std::find(sizes.begin(), sizes.end(), size) == sizes.end())
+ size = streamConfig_.formats().sizes(format)[0];
+
+ arg->fmt.pix.width = size.width;
+ arg->fmt.pix.height = size.height;
+ arg->fmt.pix.pixelformat = v4l2ToDrm(format);
+ arg->fmt.pix.field = V4L2_FIELD_NONE;
+ arg->fmt.pix.bytesperline = bplMultiplier(drmToV4L2(format)) *
+ arg->fmt.pix.width;
+ arg->fmt.pix.sizeimage = imageSize(drmToV4L2(format),
+ arg->fmt.pix.width,
+ arg->fmt.pix.height);
+ arg->fmt.pix.colorspace = V4L2_COLORSPACE_SRGB;
+
+ return 0;
+}
+
+int V4L2CameraProxy::freeBuffers()
+{
+ LOG(V4L2Compat, Debug) << "Freeing libcamera bufs";
+
+ int ret;
+ vcam_->invokeMethod(&V4L2Camera::streamOff,
+ ConnectionTypeBlocking, &ret);
+ if (ret < 0) {
+ LOG(V4L2Compat, Error) << "Failed to stop stream";
+ return ret;
+ }
+ vcam_->invokeMethod(&V4L2Camera::freeBuffers, ConnectionTypeBlocking);
+ bufferCount_ = 0;
+
+ return 0;
+}
+
+int V4L2CameraProxy::vidioc_reqbufs(struct v4l2_requestbuffers *arg)
+{
+ int ret;
+
+ LOG(V4L2Compat, Debug) << "Servicing vidioc_reqbufs";
+ if (!validateBufferType(arg->type) ||
+ !validateMemoryType(arg->memory))
+ return -EINVAL;
+
+ LOG(V4L2Compat, Debug) << arg->count << " buffers requested ";
+
+ arg->capabilities = V4L2_BUF_CAP_SUPPORTS_MMAP;
+
+ if (arg->count == 0)
+ return freeBuffers();
+
+ Size size(curV4L2Format_.fmt.pix.width, curV4L2Format_.fmt.pix.height);
+ vcam_->invokeMethod(&V4L2Camera::configure, ConnectionTypeBlocking,
+ &ret, &streamConfig_, size,
+ v4l2ToDrm(curV4L2Format_.fmt.pix.pixelformat),
+ arg->count);
+ if (ret < 0)
+ return -EINVAL;
+
+ sizeimage_ = calculateSizeImage(streamConfig_);
+ if (sizeimage_ == 0)
+ return -EINVAL;
+
+ setFmtFromConfig(streamConfig_);
+
+ arg->count = streamConfig_.bufferCount;
+ bufferCount_ = arg->count;
+
+ vcam_->invokeMethod(&V4L2Camera::allocBuffers,
+ ConnectionTypeBlocking, &ret, arg->count);
+ if (ret < 0) {
+ arg->count = 0;
+ return ret;
+ }
+
+ buffers_.resize(arg->count);
+ for (unsigned int i = 0; i < arg->count; i++) {
+ struct v4l2_buffer buf = {};
+ buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+ buf.length = curV4L2Format_.fmt.pix.sizeimage;
+ buf.memory = V4L2_MEMORY_MMAP;
+ buf.m.offset = i * curV4L2Format_.fmt.pix.sizeimage;
+ buf.index = i;
+
+ buffers_[i] = buf;
+ }
+
+ LOG(V4L2Compat, Debug) << "Allocated " << arg->count << " buffers";
+
+ return 0;
+}
+
+int V4L2CameraProxy::vidioc_querybuf(struct v4l2_buffer *arg)
+{
+ LOG(V4L2Compat, Debug) << "Servicing vidioc_querybuf";
+
+ if (!validateBufferType(arg->type) ||
+ arg->index >= bufferCount_)
+ return -EINVAL;
+
+ updateBuffers();
+
+ *arg = buffers_[arg->index];
+
+ return 0;
+}
+
+int V4L2CameraProxy::vidioc_qbuf(struct v4l2_buffer *arg)
+{
+ LOG(V4L2Compat, Debug) << "Servicing vidioc_qbuf, index = "
+ << arg->index;
+
+ if (!validateBufferType(arg->type) ||
+ !validateMemoryType(arg->memory) ||
+ arg->index >= bufferCount_)
+ return -EINVAL;
+
+ int ret;
+ vcam_->invokeMethod(&V4L2Camera::qbuf, ConnectionTypeBlocking,
+ &ret, arg->index);
+ if (ret < 0)
+ return ret;
+
+ arg->flags |= V4L2_BUF_FLAG_QUEUED;
+ arg->flags &= ~V4L2_BUF_FLAG_DONE;
+
+ return ret;
+}
+
+int V4L2CameraProxy::vidioc_dqbuf(struct v4l2_buffer *arg)
+{
+ LOG(V4L2Compat, Debug) << "Servicing vidioc_dqbuf";
+
+ if (!validateBufferType(arg->type) ||
+ !validateMemoryType(arg->memory))
+ return -EINVAL;
+
+ if (nonBlocking_ && !vcam_->bufferSema_.tryAcquire())
+ return -EAGAIN;
+ else
+ vcam_->bufferSema_.acquire();
+
+ updateBuffers();
+
+ struct v4l2_buffer &buf = buffers_[currentBuf_];
+
+ buf.flags &= ~V4L2_BUF_FLAG_QUEUED;
+ buf.length = sizeimage_;
+ *arg = buf;
+
+ currentBuf_ = (currentBuf_ + 1) % bufferCount_;
+
+ return 0;
+}
+
+int V4L2CameraProxy::vidioc_streamon(int *arg)
+{
+ LOG(V4L2Compat, Debug) << "Servicing vidioc_streamon";
+
+ if (!validateBufferType(*arg))
+ return -EINVAL;
+
+ int ret;
+ vcam_->invokeMethod(&V4L2Camera::streamOn,
+ ConnectionTypeBlocking, &ret);
+
+ return ret;
+}
+
+int V4L2CameraProxy::vidioc_streamoff(int *arg)
+{
+ LOG(V4L2Compat, Debug) << "Servicing vidioc_streamoff";
+
+ if (!validateBufferType(*arg))
+ return -EINVAL;
+
+ int ret;
+ vcam_->invokeMethod(&V4L2Camera::streamOff,
+ ConnectionTypeBlocking, &ret);
+
+ for (struct v4l2_buffer &buf : buffers_)
+ buf.flags &= ~(V4L2_BUF_FLAG_QUEUED | V4L2_BUF_FLAG_DONE);
+
+ return ret;
+}
+
+int V4L2CameraProxy::ioctl(unsigned long request, void *arg)
+{
+ int ret;
+ switch (request) {
+ case VIDIOC_QUERYCAP:
+ ret = vidioc_querycap(static_cast<struct v4l2_capability *>(arg));
+ break;
+ case VIDIOC_ENUM_FMT:
+ ret = vidioc_enum_fmt(static_cast<struct v4l2_fmtdesc *>(arg));
+ break;
+ case VIDIOC_G_FMT:
+ ret = vidioc_g_fmt(static_cast<struct v4l2_format *>(arg));
+ break;
+ case VIDIOC_S_FMT:
+ ret = vidioc_s_fmt(static_cast<struct v4l2_format *>(arg));
+ break;
+ case VIDIOC_TRY_FMT:
+ ret = vidioc_try_fmt(static_cast<struct v4l2_format *>(arg));
+ break;
+ case VIDIOC_REQBUFS:
+ ret = vidioc_reqbufs(static_cast<struct v4l2_requestbuffers *>(arg));
+ break;
+ case VIDIOC_QUERYBUF:
+ ret = vidioc_querybuf(static_cast<struct v4l2_buffer *>(arg));
+ break;
+ case VIDIOC_QBUF:
+ ret = vidioc_qbuf(static_cast<struct v4l2_buffer *>(arg));
+ break;
+ case VIDIOC_DQBUF:
+ ret = vidioc_dqbuf(static_cast<struct v4l2_buffer *>(arg));
+ break;
+ case VIDIOC_STREAMON:
+ ret = vidioc_streamon(static_cast<int *>(arg));
+ break;
+ case VIDIOC_STREAMOFF:
+ ret = vidioc_streamoff(static_cast<int *>(arg));
+ break;
+ default:
+ ret = -ENOTTY;
+ break;
+ }
+
+ if (ret < 0) {
+ errno = -ret;
+ return -1;
+ }
+
+ return ret;
+}
+
+/* \todo make libcamera export these */
+int V4L2CameraProxy::bplMultiplier(unsigned int format)
+{
+ switch (format) {
+ case V4L2_PIX_FMT_NV12:
+ case V4L2_PIX_FMT_NV21:
+ case V4L2_PIX_FMT_NV16:
+ case V4L2_PIX_FMT_NV61:
+ case V4L2_PIX_FMT_NV24:
+ case V4L2_PIX_FMT_NV42:
+ return 1;
+ case V4L2_PIX_FMT_BGR24:
+ case V4L2_PIX_FMT_RGB24:
+ return 3;
+ case V4L2_PIX_FMT_ARGB32:
+ return 4;
+ case V4L2_PIX_FMT_VYUY:
+ case V4L2_PIX_FMT_YVYU:
+ case V4L2_PIX_FMT_UYVY:
+ case V4L2_PIX_FMT_YUYV:
+ return 2;
+ default:
+ return 0;
+ };
+}
+
+int V4L2CameraProxy::imageSize(unsigned int format,
+ unsigned int width, unsigned int height)
+{
+ switch (format) {
+ case V4L2_PIX_FMT_NV12:
+ case V4L2_PIX_FMT_NV21:
+ return width * height * 3 / 2;
+ case V4L2_PIX_FMT_NV16:
+ case V4L2_PIX_FMT_NV61:
+ return width * height * 2;
+ case V4L2_PIX_FMT_NV24:
+ case V4L2_PIX_FMT_NV42:
+ return width * height * 3;
+ case V4L2_PIX_FMT_BGR24:
+ case V4L2_PIX_FMT_RGB24:
+ return width * height * 3;
+ case V4L2_PIX_FMT_ARGB32:
+ return width * height * 4;
+ case V4L2_PIX_FMT_VYUY:
+ case V4L2_PIX_FMT_YVYU:
+ case V4L2_PIX_FMT_UYVY:
+ case V4L2_PIX_FMT_YUYV:
+ return width * height * 2;
+ default:
+ return 0;
+ };
+}
+
+unsigned int V4L2CameraProxy::v4l2ToDrm(unsigned int pixelformat)
+{
+ switch (pixelformat) {
+ /* RGB formats. */
+ case V4L2_PIX_FMT_RGB24:
+ return DRM_FORMAT_BGR888;
+ case V4L2_PIX_FMT_BGR24:
+ return DRM_FORMAT_RGB888;
+ case V4L2_PIX_FMT_ARGB32:
+ return DRM_FORMAT_BGRA8888;
+
+ /* YUV packed formats. */
+ case V4L2_PIX_FMT_YUYV:
+ return DRM_FORMAT_YUYV;
+ case V4L2_PIX_FMT_YVYU:
+ return DRM_FORMAT_YVYU;
+ case V4L2_PIX_FMT_UYVY:
+ return DRM_FORMAT_UYVY;
+ case V4L2_PIX_FMT_VYUY:
+ return DRM_FORMAT_VYUY;
+
+ /* YUY planar formats. */
+ case V4L2_PIX_FMT_NV16:
+ return DRM_FORMAT_NV16;
+ case V4L2_PIX_FMT_NV61:
+ return DRM_FORMAT_NV61;
+ case V4L2_PIX_FMT_NV12:
+ return DRM_FORMAT_NV12;
+ case V4L2_PIX_FMT_NV21:
+ return DRM_FORMAT_NV21;
+ case V4L2_PIX_FMT_NV24:
+ return DRM_FORMAT_NV24;
+ case V4L2_PIX_FMT_NV42:
+ return DRM_FORMAT_NV42;
+ default:
+ return pixelformat;
+ };
+}
+
+unsigned int V4L2CameraProxy::drmToV4L2(unsigned int pixelformat)
+{
+ switch (pixelformat) {
+ /* RGB formats. */
+ case DRM_FORMAT_BGR888:
+ return V4L2_PIX_FMT_RGB24;
+ case DRM_FORMAT_RGB888:
+ return V4L2_PIX_FMT_BGR24;
+ case DRM_FORMAT_BGRA8888:
+ return V4L2_PIX_FMT_ARGB32;
+
+ /* YUV packed formats. */
+ case DRM_FORMAT_YUYV:
+ return V4L2_PIX_FMT_YUYV;
+ case DRM_FORMAT_YVYU:
+ return V4L2_PIX_FMT_YVYU;
+ case DRM_FORMAT_UYVY:
+ return V4L2_PIX_FMT_UYVY;
+ case DRM_FORMAT_VYUY:
+ return V4L2_PIX_FMT_VYUY;
+
+ /* YUY planar formats. */
+ case DRM_FORMAT_NV16:
+ return V4L2_PIX_FMT_NV16;
+ case DRM_FORMAT_NV61:
+ return V4L2_PIX_FMT_NV61;
+ case DRM_FORMAT_NV12:
+ return V4L2_PIX_FMT_NV12;
+ case DRM_FORMAT_NV21:
+ return V4L2_PIX_FMT_NV21;
+ case DRM_FORMAT_NV24:
+ return V4L2_PIX_FMT_NV24;
+ case DRM_FORMAT_NV42:
+ return V4L2_PIX_FMT_NV42;
+ default:
+ return pixelformat;
+ }
+}
diff --git a/src/v4l2/v4l2_camera_proxy.h b/src/v4l2/v4l2_camera_proxy.h
new file mode 100644
index 00000000..bef0f0af
--- /dev/null
+++ b/src/v4l2/v4l2_camera_proxy.h
@@ -0,0 +1,81 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (C) 2019, Google Inc.
+ *
+ * v4l2_camera_proxy.h - Proxy to V4L2 compatibility camera
+ */
+
+#ifndef __V4L2_CAMERA_PROXY_H__
+#define __V4L2_CAMERA_PROXY_H__
+
+#include <linux/videodev2.h>
+#include <map>
+#include <memory>
+#include <sys/types.h>
+#include <vector>
+
+#include <libcamera/camera.h>
+
+#include "v4l2_camera.h"
+
+using namespace libcamera;
+
+class V4L2CameraProxy
+{
+public:
+ V4L2CameraProxy(unsigned int index, std::shared_ptr<Camera> camera);
+
+ int open(bool nonBlocking);
+ void dup();
+ void close();
+ void *mmap(size_t length, int prot, int flags, off_t offset);
+ int munmap(void *addr, size_t length);
+
+ int ioctl(unsigned long request, void *arg);
+
+private:
+ bool validateBufferType(uint32_t type);
+ bool validateMemoryType(uint32_t memory);
+ void setFmtFromConfig(StreamConfiguration &streamConfig);
+ unsigned int calculateSizeImage(StreamConfiguration &streamConfig);
+ void querycap(std::shared_ptr<Camera> camera);
+ void updateBuffers();
+ int freeBuffers();
+
+ int vidioc_querycap(struct v4l2_capability *arg);
+ int vidioc_enum_fmt(struct v4l2_fmtdesc *arg);
+ int vidioc_g_fmt(struct v4l2_format *arg);
+ int vidioc_s_fmt(struct v4l2_format *arg);
+ int vidioc_try_fmt(struct v4l2_format *arg);
+ int vidioc_reqbufs(struct v4l2_requestbuffers *arg);
+ int vidioc_querybuf(struct v4l2_buffer *arg);
+ int vidioc_qbuf(struct v4l2_buffer *arg);
+ int vidioc_dqbuf(struct v4l2_buffer *arg);
+ int vidioc_streamon(int *arg);
+ int vidioc_streamoff(int *arg);
+
+ static int bplMultiplier(unsigned int format);
+ static int imageSize(unsigned int format, unsigned int width,
+ unsigned int height);
+
+ static unsigned int v4l2ToDrm(unsigned int pixelformat);
+ static unsigned int drmToV4L2(unsigned int pixelformat);
+
+ unsigned int refcount_;
+ unsigned int index_;
+ bool nonBlocking_;
+
+ struct v4l2_format curV4L2Format_;
+ StreamConfiguration streamConfig_;
+ struct v4l2_capability capabilities_;
+ unsigned int bufferCount_;
+ unsigned int currentBuf_;
+ unsigned int sizeimage_;
+
+ std::vector<struct v4l2_buffer> buffers_;
+ std::map<void *, unsigned int> mmaps_;
+
+ std::unique_ptr<V4L2Camera> vcam_;
+};
+
+#endif /* __V4L2_CAMERA_PROXY_H__ */
diff --git a/src/v4l2/v4l2_compat.cpp b/src/v4l2/v4l2_compat.cpp
new file mode 100644
index 00000000..171ebed6
--- /dev/null
+++ b/src/v4l2/v4l2_compat.cpp
@@ -0,0 +1,85 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (C) 2019, Google Inc.
+ *
+ * v4l2_compat.cpp - V4L2 compatibility layer
+ */
+
+#include "v4l2_compat_manager.h"
+
+#include <errno.h>
+#include <fcntl.h>
+#include <stdarg.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+
+#define LIBCAMERA_PUBLIC __attribute__((visibility("default")))
+
+using namespace libcamera;
+
+#define extract_va_arg(type, arg, last) \
+{ \
+ va_list ap; \
+ va_start(ap, last); \
+ arg = va_arg(ap, type); \
+ va_end(ap); \
+}
+
+extern "C" {
+
+LIBCAMERA_PUBLIC int open(const char *path, int oflag, ...)
+{
+ mode_t mode = 0;
+ if (oflag & O_CREAT || oflag & O_TMPFILE)
+ extract_va_arg(mode_t, mode, oflag);
+
+ return V4L2CompatManager::instance()->openat(AT_FDCWD, path,
+ oflag, mode);
+}
+
+/* _FORTIFY_SOURCE redirects open to __open_2 */
+LIBCAMERA_PUBLIC extern __typeof(open) __open_2 __attribute__ ((alias("open")));
+
+LIBCAMERA_PUBLIC int openat(int dirfd, const char *path, int oflag, ...)
+{
+ mode_t mode = 0;
+ if (oflag & O_CREAT || oflag & O_TMPFILE)
+ extract_va_arg(mode_t, mode, oflag);
+
+ return V4L2CompatManager::instance()->openat(dirfd, path, oflag, mode);
+}
+
+LIBCAMERA_PUBLIC extern __typeof(openat) __openat_2 __attribute__ ((alias("openat")));
+
+LIBCAMERA_PUBLIC int dup(int oldfd)
+{
+ return V4L2CompatManager::instance()->dup(oldfd);
+}
+
+LIBCAMERA_PUBLIC int close(int fd)
+{
+ return V4L2CompatManager::instance()->close(fd);
+}
+
+LIBCAMERA_PUBLIC void *mmap(void *addr, size_t length, int prot, int flags,
+ int fd, off_t offset)
+{
+ return V4L2CompatManager::instance()->mmap(addr, length, prot, flags,
+ fd, offset);
+}
+
+LIBCAMERA_PUBLIC int munmap(void *addr, size_t length)
+{
+ return V4L2CompatManager::instance()->munmap(addr, length);
+}
+
+LIBCAMERA_PUBLIC int ioctl(int fd, unsigned long request, ...)
+{
+ void *arg;
+ extract_va_arg(void *, arg, request);
+
+ return V4L2CompatManager::instance()->ioctl(fd, request, arg);
+}
+
+}
diff --git a/src/v4l2/v4l2_compat_manager.cpp b/src/v4l2/v4l2_compat_manager.cpp
new file mode 100644
index 00000000..a3d69374
--- /dev/null
+++ b/src/v4l2/v4l2_compat_manager.cpp
@@ -0,0 +1,250 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (C) 2019, Google Inc.
+ *
+ * v4l2_compat_manager.cpp - V4L2 compatibility manager
+ */
+
+#include "v4l2_compat_manager.h"
+
+#include <dlfcn.h>
+#include <fcntl.h>
+#include <map>
+#include <stdarg.h>
+#include <string.h>
+#include <sys/eventfd.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+#include <sys/sysmacros.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include <libcamera/camera.h>
+#include <libcamera/camera_manager.h>
+
+#include "log.h"
+
+using namespace libcamera;
+
+LOG_DEFINE_CATEGORY(V4L2Compat)
+
+V4L2CompatManager::V4L2CompatManager()
+ : cm_(nullptr), initialized_(false)
+{
+ openat_func_ = (openat_func_t)dlsym(RTLD_NEXT, "openat");
+ dup_func_ = (dup_func_t )dlsym(RTLD_NEXT, "dup");
+ close_func_ = (close_func_t )dlsym(RTLD_NEXT, "close");
+ ioctl_func_ = (ioctl_func_t )dlsym(RTLD_NEXT, "ioctl");
+ mmap_func_ = (mmap_func_t )dlsym(RTLD_NEXT, "mmap");
+ munmap_func_ = (munmap_func_t)dlsym(RTLD_NEXT, "munmap");
+}
+
+V4L2CompatManager::~V4L2CompatManager()
+{
+ devices_.clear();
+ mmaps_.clear();
+
+ if (isRunning()) {
+ exit(0);
+ /* \todo Wait with a timeout, just in case. */
+ wait();
+ }
+}
+
+int V4L2CompatManager::init()
+{
+ start();
+
+ MutexLocker locker(mutex_);
+ cv_.wait(locker, [&] { return initialized_; });
+
+ return 0;
+}
+
+void V4L2CompatManager::run()
+{
+ cm_ = new CameraManager();
+
+ int ret = cm_->start();
+ if (ret) {
+ LOG(V4L2Compat, Error) << "Failed to start camera manager: "
+ << strerror(-ret);
+ return;
+ }
+
+ LOG(V4L2Compat, Debug) << "Started camera manager";
+
+ /*
+ * For each Camera registered in the system, a V4L2CameraProxy gets
+ * created here to wrap a camera device.
+ */
+ unsigned int index = 0;
+ for (auto &camera : cm_->cameras()) {
+ V4L2CameraProxy *proxy = new V4L2CameraProxy(index, camera);
+ proxies_.emplace_back(proxy);
+ ++index;
+ }
+
+ /*
+ * libcamera has been initialized. Unlock the init() caller as we're
+ * now ready to handle calls from the framework.
+ */
+ mutex_.lock();
+ initialized_ = true;
+ mutex_.unlock();
+ cv_.notify_one();
+
+ /* Now start processing events and messages. */
+ exec();
+
+ proxies_.clear();
+ cm_->stop();
+ delete cm_;
+ cm_ = nullptr;
+}
+
+V4L2CompatManager *V4L2CompatManager::instance()
+{
+ static V4L2CompatManager instance;
+ return &instance;
+}
+
+V4L2CameraProxy *V4L2CompatManager::getProxy(int fd)
+{
+ auto device = devices_.find(fd);
+ if (device == devices_.end())
+ return nullptr;
+
+ return device->second;
+}
+
+int V4L2CompatManager::getCameraIndex(int fd)
+{
+ struct stat statbuf;
+ int ret = fstat(fd, &statbuf);
+ if (ret < 0)
+ return -1;
+
+ std::shared_ptr<Camera> target = cm_->get(statbuf.st_rdev);
+ if (!target)
+ return -1;
+
+ unsigned int index = 0;
+ for (auto &camera : cm_->cameras()) {
+ if (camera == target)
+ return index;
+ ++index;
+ }
+
+ return -1;
+}
+
+int V4L2CompatManager::openat(int dirfd, const char *path, int oflag, mode_t mode)
+{
+ int fd = openat_func_(dirfd, path, oflag, mode);
+ if (fd < 0)
+ return fd;
+
+ struct stat statbuf;
+ int ret = fstat(fd, &statbuf);
+ if (ret < 0 || (statbuf.st_mode & S_IFMT) != S_IFCHR ||
+ major(statbuf.st_rdev) != 81)
+ return fd;
+
+ if (!isRunning())
+ init();
+
+ ret = getCameraIndex(fd);
+ if (ret < 0) {
+ LOG(V4L2Compat, Info) << "No camera found for " << path;
+ return fd;
+ }
+
+ close_func_(fd);
+
+ unsigned int camera_index = static_cast<unsigned int>(ret);
+
+ V4L2CameraProxy *proxy = proxies_[camera_index].get();
+ ret = proxy->open(oflag & O_NONBLOCK);
+ if (ret < 0)
+ return ret;
+
+ int efd = eventfd(0, oflag & (O_CLOEXEC | O_NONBLOCK));
+ if (efd < 0) {
+ proxy->close();
+ return efd;
+ }
+
+ devices_.emplace(efd, proxy);
+
+ return efd;
+}
+
+int V4L2CompatManager::dup(int oldfd)
+{
+ int newfd = dup_func_(oldfd);
+ if (newfd < 0)
+ return newfd;
+
+ auto device = devices_.find(oldfd);
+ if (device != devices_.end()) {
+ V4L2CameraProxy *proxy = device->second;
+ devices_[newfd] = proxy;
+ proxy->dup();
+ }
+
+ return newfd;
+}
+
+int V4L2CompatManager::close(int fd)
+{
+ V4L2CameraProxy *proxy = getProxy(fd);
+ if (proxy) {
+ proxy->close();
+ devices_.erase(fd);
+ return 0;
+ }
+
+ return close_func_(fd);
+}
+
+void *V4L2CompatManager::mmap(void *addr, size_t length, int prot, int flags,
+ int fd, off_t offset)
+{
+ V4L2CameraProxy *proxy = getProxy(fd);
+ if (!proxy)
+ return mmap_func_(addr, length, prot, flags, fd, offset);
+
+ void *map = proxy->mmap(length, prot, flags, offset);
+ if (map == MAP_FAILED)
+ return map;
+
+ mmaps_[map] = proxy;
+ return map;
+}
+
+int V4L2CompatManager::munmap(void *addr, size_t length)
+{
+ auto device = mmaps_.find(addr);
+ if (device == mmaps_.end())
+ return munmap_func_(addr, length);
+
+ V4L2CameraProxy *proxy = device->second;
+
+ int ret = proxy->munmap(addr, length);
+ if (ret < 0)
+ return ret;
+
+ mmaps_.erase(device);
+
+ return 0;
+}
+
+int V4L2CompatManager::ioctl(int fd, unsigned long request, void *arg)
+{
+ V4L2CameraProxy *proxy = getProxy(fd);
+ if (!proxy)
+ return ioctl_func_(fd, request, arg);
+
+ return proxy->ioctl(request, arg);
+}
diff --git a/src/v4l2/v4l2_compat_manager.h b/src/v4l2/v4l2_compat_manager.h
new file mode 100644
index 00000000..dd9d3210
--- /dev/null
+++ b/src/v4l2/v4l2_compat_manager.h
@@ -0,0 +1,77 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (C) 2019, Google Inc.
+ *
+ * v4l2_compat_manager.h - V4L2 compatibility manager
+ */
+
+#ifndef __V4L2_COMPAT_MANAGER_H__
+#define __V4L2_COMPAT_MANAGER_H__
+
+#include <condition_variable>
+#include <fcntl.h>
+#include <map>
+#include <memory>
+#include <mutex>
+#include <sys/types.h>
+#include <vector>
+
+#include <libcamera/camera_manager.h>
+
+#include "thread.h"
+#include "v4l2_camera_proxy.h"
+
+using namespace libcamera;
+
+class V4L2CompatManager : public Thread
+{
+public:
+ static V4L2CompatManager *instance();
+
+ int init();
+
+ V4L2CameraProxy *getProxy(int fd);
+
+ int openat(int dirfd, const char *path, int oflag, mode_t mode);
+
+ int dup(int oldfd);
+ int close(int fd);
+ void *mmap(void *addr, size_t length, int prot, int flags,
+ int fd, off_t offset);
+ int munmap(void *addr, size_t length);
+ int ioctl(int fd, unsigned long request, void *arg);
+
+private:
+ V4L2CompatManager();
+ ~V4L2CompatManager();
+
+ void run() override;
+ int getCameraIndex(int fd);
+
+ typedef int (*openat_func_t)(int dirfd, const char *path, int oflag, ...);
+ typedef int (*dup_func_t)(int oldfd);
+ typedef int (*close_func_t)(int fd);
+ typedef int (*ioctl_func_t)(int fd, unsigned long request, ...);
+ typedef void *(*mmap_func_t)(void *addr, size_t length, int prot,
+ int flags, int fd, off_t offset);
+ typedef int (*munmap_func_t)(void *addr, size_t length);
+
+ openat_func_t openat_func_;
+ dup_func_t dup_func_;
+ close_func_t close_func_;
+ ioctl_func_t ioctl_func_;
+ mmap_func_t mmap_func_;
+ munmap_func_t munmap_func_;
+
+ CameraManager *cm_;
+
+ std::mutex mutex_;
+ std::condition_variable cv_;
+ bool initialized_;
+
+ std::vector<std::unique_ptr<V4L2CameraProxy>> proxies_;
+ std::map<int, V4L2CameraProxy *> devices_;
+ std::map<void *, V4L2CameraProxy *> mmaps_;
+};
+
+#endif /* __V4L2_COMPAT_MANAGER_H__ */
--
2.24.1
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