Revert of Linux Video Capture: Add V4L2VideoCaptureDelegate{Single,Multi}Plane.

media/video/capture/linux/video_capture_device_linux.cc

Index: media/video/capture/linux/video_capture_device_linux.cc
diff --git a/media/video/capture/linux/video_capture_device_linux.cc b/media/video/capture/linux/video_capture_device_linux.cc
index 500be2c8fff3285669707ca8be10eecbc7a88e52..b9fb195f8ae4b0e670b7c482bd3a5245460f35c8 100644
--- a/media/video/capture/linux/video_capture_device_linux.cc
+++ b/media/video/capture/linux/video_capture_device_linux.cc
@@ -4,20 +4,100 @@
 
 #include "media/video/capture/linux/video_capture_device_linux.h"
 
+#include <errno.h>
+#include <fcntl.h>
+#include <poll.h>
 #if defined(OS_OPENBSD)
 #include <sys/videoio.h>
 #else
 #include <linux/videodev2.h>
 #endif
+#include <sys/ioctl.h>
+#include <sys/mman.h>
 
 #include <list>
 #include <string>
 
 #include "base/bind.h"
+#include "base/files/file_enumerator.h"
+#include "base/files/scoped_file.h"
+#include "base/posix/eintr_wrapper.h"
 #include "base/strings/stringprintf.h"
-#include "media/video/capture/linux/v4l2_capture_delegate.h"
 
 namespace media {
+
+#define GET_V4L2_FOURCC_CHAR(a, index) ((char)( ((a) >> (8 * index)) & 0xff))
+
+// Desired number of video buffers to allocate. The actual number of allocated
+// buffers by v4l2 driver can be higher or lower than this number.
+// kNumVideoBuffers should not be too small, or Chrome may not return enough
+// buffers back to driver in time.
+const uint32 kNumVideoBuffers = 4;
+// Timeout in milliseconds v4l2_thread_ blocks waiting for a frame from the hw.
+enum { kCaptureTimeoutMs = 200 };
+// The number of continuous timeouts tolerated before treated as error.
+enum { kContinuousTimeoutLimit = 10 };
+// MJPEG is preferred if the width or height is larger than this.
+enum { kMjpegWidth = 640 };
+enum { kMjpegHeight = 480 };
+// Typical framerate, in fps
+enum { kTypicalFramerate = 30 };
+
+class VideoCaptureDeviceLinux::V4L2CaptureDelegate
+    : public base::RefCountedThreadSafe<V4L2CaptureDelegate>{
+ public:
+  V4L2CaptureDelegate(
+      const Name& device_name,
+      const scoped_refptr<base::SingleThreadTaskRunner>  v4l2_task_runner,
+      int power_line_frequency);
+
+  void AllocateAndStart(int width,
+                        int height,
+                        float frame_rate,
+                        scoped_ptr<Client> client);
+  void StopAndDeAllocate();
+  void SetRotation(int rotation);
+  bool DeAllocateVideoBuffers();
+
+ private:
+  // Buffers used to receive captured frames from v4l2.
+  struct Buffer {
+    Buffer() : start(0), length(0) {}
+    void* start;
+    size_t length;
+  };
+
+  friend class base::RefCountedThreadSafe<V4L2CaptureDelegate>;
+   ~V4L2CaptureDelegate();
+
+  void DoCapture();
+  bool AllocateVideoBuffers();
+  void SetErrorState(const std::string& reason);
+
+  const scoped_refptr<base::SingleThreadTaskRunner> v4l2_task_runner_;
+
+  bool is_capturing_;
+  scoped_ptr<VideoCaptureDevice::Client> client_;
+  const Name device_name_;
+  base::ScopedFD device_fd_;  // File descriptor for the opened camera device.
+  Buffer* buffer_pool_;
+  int buffer_pool_size_;  // Number of allocated buffers.
+  int timeout_count_;
+  VideoCaptureFormat capture_format_;
+  const int power_line_frequency_;
+
+  // Clockwise rotation in degrees.  This value should be 0, 90, 180, or 270.
+  int rotation_;
+
+  DISALLOW_IMPLICIT_CONSTRUCTORS(V4L2CaptureDelegate);
+};
+
+// V4L2 color formats VideoCaptureDeviceLinux support.
+static const int32 kV4l2RawFmts[] = {
+  V4L2_PIX_FMT_YUV420,
+  V4L2_PIX_FMT_YUYV,
+  V4L2_PIX_FMT_UYVY
+};
 
 // USB VID and PID are both 4 bytes long.
 static const size_t kVidPidSize = 4;
@@ -42,18 +122,48 @@
   return true;
 }
 
-// Translates Video4Linux pixel formats to Chromium pixel formats.
+// This function translates Video4Linux pixel formats to Chromium pixel formats,
+// should only support those listed in GetListOfUsableFourCCs.
 // static
 VideoPixelFormat VideoCaptureDeviceLinux::V4l2FourCcToChromiumPixelFormat(
     uint32 v4l2_fourcc) {
-  return V4L2CaptureDelegate::V4l2FourCcToChromiumPixelFormat(v4l2_fourcc);
-}
-
-// Gets a list of usable Four CC formats prioritised.
+  const struct {
+    uint32 fourcc;
+    VideoPixelFormat pixel_format;
+  } kFourCcAndChromiumPixelFormat[] = {
+    {V4L2_PIX_FMT_YUV420, PIXEL_FORMAT_I420},
+    {V4L2_PIX_FMT_YUYV, PIXEL_FORMAT_YUY2},
+    {V4L2_PIX_FMT_UYVY, PIXEL_FORMAT_UYVY},
+    {V4L2_PIX_FMT_MJPEG, PIXEL_FORMAT_MJPEG},
+    {V4L2_PIX_FMT_JPEG, PIXEL_FORMAT_MJPEG},
+  };
+  for (const auto& fourcc_and_pixel_format : kFourCcAndChromiumPixelFormat) {
+    if (fourcc_and_pixel_format.fourcc == v4l2_fourcc)
+      return fourcc_and_pixel_format.pixel_format;
+  }
+  DVLOG(1) << "Unsupported pixel format: "
+           << GET_V4L2_FOURCC_CHAR(v4l2_fourcc, 0)
+           << GET_V4L2_FOURCC_CHAR(v4l2_fourcc, 1)
+           << GET_V4L2_FOURCC_CHAR(v4l2_fourcc, 2)
+           << GET_V4L2_FOURCC_CHAR(v4l2_fourcc, 3);
+  return PIXEL_FORMAT_UNKNOWN;
+}
+
 // static
-std::list<uint32_t> VideoCaptureDeviceLinux::GetListOfUsableFourCCs(
+std::list<int> VideoCaptureDeviceLinux::GetListOfUsableFourCCs(
     bool favour_mjpeg) {
-  return V4L2CaptureDelegate::GetListOfUsableFourCcs(favour_mjpeg);
+  std::list<int> fourccs;
+  for (size_t i = 0; i < arraysize(kV4l2RawFmts); ++i)
+    fourccs.push_back(kV4l2RawFmts[i]);
+  if (favour_mjpeg)
+    fourccs.push_front(V4L2_PIX_FMT_MJPEG);
+  else
+    fourccs.push_back(V4L2_PIX_FMT_MJPEG);
+
+  // JPEG works as MJPEG on some gspca webcams from field reports.
+  // Put it as the least preferred format.
+  fourccs.push_back(V4L2_PIX_FMT_JPEG);
+  return fourccs;
 }
 
 const std::string VideoCaptureDevice::Name::GetModel() const {
@@ -97,21 +207,18 @@
   if (v4l2_thread_.IsRunning())
     return;  // Wrong state.
   v4l2_thread_.Start();
-
-  const int line_frequency =
-      TranslatePowerLineFrequencyToV4L2(GetPowerLineFrequencyForLocation());
-  capture_impl_ = V4L2CaptureDelegate::CreateV4L2CaptureDelegate(
-      device_name_, v4l2_thread_.message_loop_proxy(), line_frequency);
-  if (!capture_impl_) {
-    client->OnError("Failed to create VideoCaptureDelegate");
-    return;
-  }
+  capture_impl_ = new V4L2CaptureDelegate(device_name_,
+                                          v4l2_thread_.message_loop_proxy(),
+                                          GetPowerLineFrequencyForLocation());
   v4l2_thread_.message_loop()->PostTask(
       FROM_HERE,
-      base::Bind(&V4L2CaptureDelegate::AllocateAndStart, capture_impl_,
-                 params.requested_format.frame_size.width(),
-                 params.requested_format.frame_size.height(),
-                 params.requested_format.frame_rate, base::Passed(&client)));
+      base::Bind(
+          &VideoCaptureDeviceLinux::V4L2CaptureDelegate::AllocateAndStart,
+          capture_impl_,
+          params.requested_format.frame_size.width(),
+          params.requested_format.frame_size.height(),
+          params.requested_format.frame_rate,
+          base::Passed(&client)));
 }
 
 void VideoCaptureDeviceLinux::StopAndDeAllocate() {
@@ -119,31 +226,309 @@
     return;  // Wrong state.
   v4l2_thread_.message_loop()->PostTask(
       FROM_HERE,
-      base::Bind(&V4L2CaptureDelegate::StopAndDeAllocate, capture_impl_));
+      base::Bind(
+          &VideoCaptureDeviceLinux::V4L2CaptureDelegate::StopAndDeAllocate,
+          capture_impl_));
   v4l2_thread_.Stop();
-
+  // TODO(mcasas): VCDLinux called DeAllocateVideoBuffers() a second time after
+  // stopping |v4l2_thread_| to make sure buffers were completely deallocated.
+  // Investigate if that's needed, otherwise remove the following line and make
+  // V4L2CaptureDelegate::DeAllocateVideoBuffers() private.
+  capture_impl_->DeAllocateVideoBuffers();
   capture_impl_ = NULL;
 }
 
 void VideoCaptureDeviceLinux::SetRotation(int rotation) {
   if (v4l2_thread_.IsRunning()) {
     v4l2_thread_.message_loop()->PostTask(
-        FROM_HERE, base::Bind(&V4L2CaptureDelegate::SetRotation,
-                              capture_impl_, rotation));
-  }
-}
-
-// static
-int VideoCaptureDeviceLinux::TranslatePowerLineFrequencyToV4L2(int frequency) {
-  switch (frequency) {
-    case kPowerLine50Hz:
-      return V4L2_CID_POWER_LINE_FREQUENCY_50HZ;
-    case kPowerLine60Hz:
-      return V4L2_CID_POWER_LINE_FREQUENCY_60HZ;
-    default:
-      // If we have no idea of the frequency, at least try and set it to AUTO.
-      return V4L2_CID_POWER_LINE_FREQUENCY_AUTO;
-  }
+        FROM_HERE,
+        base::Bind(
+            &VideoCaptureDeviceLinux::V4L2CaptureDelegate::SetRotation,
+            capture_impl_,
+            rotation));
+  }
+}
+
+VideoCaptureDeviceLinux::V4L2CaptureDelegate::V4L2CaptureDelegate(
+        const Name& device_name,
+        const scoped_refptr<base::SingleThreadTaskRunner> v4l2_task_runner,
+        int power_line_frequency)
+    : v4l2_task_runner_(v4l2_task_runner),
+      is_capturing_(false),
+      device_name_(device_name),
+      buffer_pool_(NULL),
+      buffer_pool_size_(0),
+      timeout_count_(0),
+      power_line_frequency_(power_line_frequency),
+      rotation_(0) {
+}
+
+VideoCaptureDeviceLinux::V4L2CaptureDelegate::~V4L2CaptureDelegate() {
+  DCHECK(!client_);
+}
+
+void VideoCaptureDeviceLinux::V4L2CaptureDelegate::AllocateAndStart(
+    int width,
+    int height,
+    float frame_rate,
+    scoped_ptr<Client> client) {
+  DCHECK(v4l2_task_runner_->BelongsToCurrentThread());
+  DCHECK(client);
+  client_ = client.Pass();
+
+  // Need to open camera with O_RDWR after Linux kernel 3.3.
+  device_fd_.reset(HANDLE_EINTR(open(device_name_.id().c_str(), O_RDWR)));
+  if (!device_fd_.is_valid()) {
+    SetErrorState("Failed to open V4L2 device driver file.");
+    return;
+  }
+
+  v4l2_capability cap = {};
+  if (!((HANDLE_EINTR(ioctl(device_fd_.get(), VIDIOC_QUERYCAP, &cap)) == 0) &&
+      (cap.capabilities & V4L2_CAP_VIDEO_CAPTURE &&
+      !(cap.capabilities & V4L2_CAP_VIDEO_OUTPUT)))) {
+    device_fd_.reset();
+    SetErrorState("This is not a V4L2 video capture device");
+    return;
+  }
+
+  // Get supported video formats in preferred order.
+  // For large resolutions, favour mjpeg over raw formats.
+  const std::list<int>& desired_v4l2_formats =
+      GetListOfUsableFourCCs(width > kMjpegWidth || height > kMjpegHeight);
+  std::list<int>::const_iterator best = desired_v4l2_formats.end();
+
+  v4l2_fmtdesc fmtdesc = {};
+  fmtdesc.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+  for (; HANDLE_EINTR(ioctl(device_fd_.get(), VIDIOC_ENUM_FMT, &fmtdesc)) == 0;
+       ++fmtdesc.index) {
+    best = std::find(desired_v4l2_formats.begin(), best, fmtdesc.pixelformat);
+  }
+  if (best == desired_v4l2_formats.end()) {
+    SetErrorState("Failed to find a supported camera format.");
+    return;
+  }
+
+  v4l2_format video_fmt = {};
+  video_fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+  video_fmt.fmt.pix.sizeimage = 0;
+  video_fmt.fmt.pix.width = width;
+  video_fmt.fmt.pix.height = height;
+  video_fmt.fmt.pix.pixelformat = *best;
+  if (HANDLE_EINTR(ioctl(device_fd_.get(), VIDIOC_S_FMT, &video_fmt)) < 0) {
+    SetErrorState("Failed to set video capture format");
+    return;
+  }
+
+  // Set capture framerate in the form of capture interval.
+  v4l2_streamparm streamparm = {};
+  streamparm.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+  // The following line checks that the driver knows about framerate get/set.
+  if (HANDLE_EINTR(ioctl(device_fd_.get(), VIDIOC_G_PARM, &streamparm)) >= 0) {
+    // Now check if the device is able to accept a capture framerate set.
+    if (streamparm.parm.capture.capability & V4L2_CAP_TIMEPERFRAME) {
+      // |frame_rate| is float, approximate by a fraction.
+      streamparm.parm.capture.timeperframe.numerator =
+          media::kFrameRatePrecision;
+      streamparm.parm.capture.timeperframe.denominator = (frame_rate) ?
+          (frame_rate * media::kFrameRatePrecision) :
+          (kTypicalFramerate * media::kFrameRatePrecision);
+
+      if (HANDLE_EINTR(ioctl(device_fd_.get(), VIDIOC_S_PARM, &streamparm)) <
+          0) {
+        SetErrorState("Failed to set camera framerate");
+        return;
+      }
+      DVLOG(2) << "Actual camera driverframerate: "
+               << streamparm.parm.capture.timeperframe.denominator << "/"
+               << streamparm.parm.capture.timeperframe.numerator;
+    }
+  }
+  // TODO(mcasas): what should be done if the camera driver does not allow
+  // framerate configuration, or the actual one is different from the desired?
+
+  // Set anti-banding/anti-flicker to 50/60Hz. May fail due to not supported
+  // operation (|errno| == EINVAL in this case) or plain failure.
+  if ((power_line_frequency_ == kPowerLine50Hz) ||
+      (power_line_frequency_ == kPowerLine60Hz)) {
+    struct v4l2_control control = {};
+    control.id = V4L2_CID_POWER_LINE_FREQUENCY;
+    control.value = (power_line_frequency_ == kPowerLine50Hz)
+                        ? V4L2_CID_POWER_LINE_FREQUENCY_50HZ
+                        : V4L2_CID_POWER_LINE_FREQUENCY_60HZ;
+    HANDLE_EINTR(ioctl(device_fd_.get(), VIDIOC_S_CTRL, &control));
+  }
+
+  capture_format_.frame_size.SetSize(video_fmt.fmt.pix.width,
+                                     video_fmt.fmt.pix.height);
+  capture_format_.frame_rate = frame_rate;
+  capture_format_.pixel_format =
+      V4l2FourCcToChromiumPixelFormat(video_fmt.fmt.pix.pixelformat);
+
+  if (!AllocateVideoBuffers()) {
+    SetErrorState("Allocate buffer failed (Cannot recover from this error)");
+    return;
+  }
+
+  const v4l2_buf_type type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+  if (HANDLE_EINTR(ioctl(device_fd_.get(), VIDIOC_STREAMON, &type)) < 0) {
+    SetErrorState("VIDIOC_STREAMON failed");
+    return;
+  }
+
+  is_capturing_ = true;
+  // Post task to start fetching frames from v4l2.
+  v4l2_task_runner_->PostTask(
+      FROM_HERE,
+      base::Bind(&VideoCaptureDeviceLinux::V4L2CaptureDelegate::DoCapture,
+                 this));
+}
+
+void VideoCaptureDeviceLinux::V4L2CaptureDelegate::StopAndDeAllocate() {
+  DCHECK(v4l2_task_runner_->BelongsToCurrentThread());
+
+  const v4l2_buf_type type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+  if (HANDLE_EINTR(ioctl(device_fd_.get(), VIDIOC_STREAMOFF, &type)) < 0) {
+    SetErrorState("VIDIOC_STREAMOFF failed");
+    return;
+  }
+  // We don't dare to deallocate the buffers if we can't stop the capture
+  // device.
+  if (!DeAllocateVideoBuffers())
+    SetErrorState("Failed to reset buffers");
+
+  // We need to close and open the device if we want to change the settings.
+  // Otherwise VIDIOC_S_FMT will return error. Sad but true.
+  device_fd_.reset();
+  is_capturing_ = false;
+  client_.reset();
+}
+
+void VideoCaptureDeviceLinux::V4L2CaptureDelegate::SetRotation(int rotation) {
+  DCHECK(v4l2_task_runner_->BelongsToCurrentThread());
+  DCHECK(rotation >= 0 && rotation < 360 && rotation % 90 == 0);
+  rotation_ = rotation;
+}
+
+void VideoCaptureDeviceLinux::V4L2CaptureDelegate::DoCapture() {
+  DCHECK(v4l2_task_runner_->BelongsToCurrentThread());
+  if (!is_capturing_)
+    return;
+
+  pollfd device_pfd = {};
+  device_pfd.fd = device_fd_.get();
+  device_pfd.events = POLLIN;
+  const int result = HANDLE_EINTR(poll(&device_pfd, 1, kCaptureTimeoutMs));
+  if (result < 0) {
+    SetErrorState("Poll failed");
+    return;
+  }
+  // Check if poll() timed out; track the amount of times it did in a row and
+  // throw an error if it times out too many times.
+  if (result == 0) {
+    timeout_count_++;
+    if (timeout_count_ >= kContinuousTimeoutLimit) {
+      SetErrorState("Multiple continuous timeouts while read-polling.");
+      timeout_count_ = 0;
+      return;
+    }
+  } else {
+    timeout_count_ = 0;
+  }
+
+  // Check if the driver has filled a buffer.
+  if (device_pfd.revents & POLLIN) {
+    v4l2_buffer buffer = {};
+     buffer.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+     buffer.memory = V4L2_MEMORY_MMAP;
+    if (HANDLE_EINTR(ioctl(device_fd_.get(), VIDIOC_DQBUF, &buffer)) < 0) {
+      SetErrorState("Failed to dequeue capture buffer");
+      return;
+    }
+    client_->OnIncomingCapturedData(
+        static_cast<uint8*>(buffer_pool_[buffer.index].start),
+        buffer.bytesused,
+        capture_format_,
+        rotation_,
+        base::TimeTicks::Now());
+
+    if (HANDLE_EINTR(ioctl(device_fd_.get(), VIDIOC_QBUF, &buffer)) < 0)
+      SetErrorState("Failed to enqueue capture buffer");
+  }
+
+  v4l2_task_runner_->PostTask(
+      FROM_HERE,
+      base::Bind(&VideoCaptureDeviceLinux::V4L2CaptureDelegate::DoCapture,
+                 this));
+}
+
+bool VideoCaptureDeviceLinux::V4L2CaptureDelegate::AllocateVideoBuffers() {
+  v4l2_requestbuffers r_buffer = {};
+  r_buffer.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+  r_buffer.memory = V4L2_MEMORY_MMAP;
+  r_buffer.count = kNumVideoBuffers;
+  if (HANDLE_EINTR(ioctl(device_fd_.get(), VIDIOC_REQBUFS, &r_buffer)) < 0) {
+    DLOG(ERROR) << "Error requesting MMAP buffers from V4L2";
+    return false;
+  }
+  buffer_pool_size_ = r_buffer.count;
+  buffer_pool_ = new Buffer[buffer_pool_size_];
+  for (unsigned int i = 0; i < r_buffer.count; ++i) {
+    v4l2_buffer buffer = {};
+    buffer.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+    buffer.memory = V4L2_MEMORY_MMAP;
+    buffer.index = i;
+    buffer.length = 1;
+    if (HANDLE_EINTR(ioctl(device_fd_.get(), VIDIOC_QUERYBUF, &buffer)) < 0) {
+      DLOG(ERROR) << "Error querying status of a MMAP V4L2 buffer";
+      return false;
+    }
+
+    // Some devices require mmap() to be called with both READ and WRITE.
+    // See http://crbug.com/178582.
+    buffer_pool_[i].start = mmap(NULL, buffer.length, PROT_READ | PROT_WRITE,
+        MAP_SHARED, device_fd_.get(), buffer.m.offset);
+    if (buffer_pool_[i].start == MAP_FAILED) {
+      DLOG(ERROR) << "Error mmmap()ing a V4L2 buffer into userspace";
+      return false;
+    }
+
+    buffer_pool_[i].length = buffer.length;
+    // Enqueue the buffer in the drivers incoming queue.
+    if (HANDLE_EINTR(ioctl(device_fd_.get(), VIDIOC_QBUF, &buffer)) < 0) {
+      DLOG(ERROR)
+          << "Error enqueuing a V4L2 buffer back to the drivers incoming queue";
+      return false;
+    }
+  }
+  return true;
+}
+
+bool VideoCaptureDeviceLinux::V4L2CaptureDelegate::DeAllocateVideoBuffers() {
+  if (!buffer_pool_)
+    return true;
+
+  for (int i = 0; i < buffer_pool_size_; ++i)
+    munmap(buffer_pool_[i].start, buffer_pool_[i].length);
+
+  v4l2_requestbuffers r_buffer = {};
+  r_buffer.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+  r_buffer.memory = V4L2_MEMORY_MMAP;
+  r_buffer.count = 0;
+  if (HANDLE_EINTR(ioctl(device_fd_.get(), VIDIOC_REQBUFS, &r_buffer)) < 0)
+    return false;
+
+  delete [] buffer_pool_;
+  buffer_pool_ = NULL;
+  buffer_pool_size_ = 0;
+  return true;
+}
+
+void VideoCaptureDeviceLinux::V4L2CaptureDelegate::SetErrorState(
+    const std::string& reason) {
+  DCHECK(v4l2_task_runner_->BelongsToCurrentThread());
+  is_capturing_ = false;
+  client_->OnError(reason);
 }
 
 }  // namespace media