[libcamera-devel] [PATCH v6 5/5] v4l2: v4l2_compat: Add V4L2 compatibility layer
Laurent Pinchart
laurent.pinchart at ideasonboard.com
Sat Jan 4 01:35:14 CET 2020
Hi Paul,
Thank you for the patch.
On Fri, Jan 03, 2020 at 07:14:13PM -0500, Paul Elder wrote:
> 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));
static_cast<char *>(...) instead of (char *).
> + 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));
Same here.
Reviewed-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
and feel free to push :-)
> + 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__ */
--
Regards,
Laurent Pinchart
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