Make V4L2CaptureDelegate non-ref-counted

media/capture/video/linux/v4l2_capture_delegate.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "media/capture/video/linux/v4l2_capture_delegate.h"
 
 #include <linux/version.h>
 #include <linux/videodev2.h>
 #include <poll.h>
 #include <sys/fcntl.h>
@@ skipping 356 matching lines @@
 
 V4L2CaptureDelegate::V4L2CaptureDelegate(
     const VideoCaptureDeviceDescriptor& device_descriptor,
     const scoped_refptr<base::SingleThreadTaskRunner>& v4l2_task_runner,
     int power_line_frequency)
     : v4l2_task_runner_(v4l2_task_runner),
       device_descriptor_(device_descriptor),
       power_line_frequency_(power_line_frequency),
       is_capturing_(false),
       timeout_count_(0),
-      rotation_(0) {}
+      rotation_(0),
+      weak_factory_(this) {}
 
 void V4L2CaptureDelegate::AllocateAndStart(
     int width,
     int height,
     float frame_rate,
     std::unique_ptr<VideoCaptureDevice::Client> client) {
   DCHECK(v4l2_task_runner_->BelongsToCurrentThread());
   DCHECK(client);
   client_ = std::move(client);
 
@@ skipping 111 matching lines @@
       0) {
     SetErrorState(FROM_HERE, "VIDIOC_STREAMON failed");
     return;
   }
 
   client_->OnStarted();
   is_capturing_ = true;
 
   // Post task to start fetching frames from v4l2.
   v4l2_task_runner_->PostTask(
-      FROM_HERE, base::Bind(&V4L2CaptureDelegate::DoCapture, this));
+      FROM_HERE, base::Bind(&V4L2CaptureDelegate::DoCapture, GetWeakPtr()));
 }
 
 void V4L2CaptureDelegate::StopAndDeAllocate() {
   DCHECK(v4l2_task_runner_->BelongsToCurrentThread());
   // The order is important: stop streaming, clear |buffer_pool_|,
   // thus munmap()ing the v4l2_buffers, and then return them to the OS.
   v4l2_buf_type capture_type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
   if (HANDLE_EINTR(ioctl(device_fd_.get(), VIDIOC_STREAMOFF, &capture_type)) <
       0) {
     SetErrorState(FROM_HERE, "VIDIOC_STREAMOFF failed");
@@ skipping 187 matching lines @@
 
   callback.Run(true);
 }
 
 void V4L2CaptureDelegate::SetRotation(int rotation) {
   DCHECK(v4l2_task_runner_->BelongsToCurrentThread());
   DCHECK(rotation >= 0 && rotation < 360 && rotation % 90 == 0);
   rotation_ = rotation;
 }
 
+base::WeakPtr<V4L2CaptureDelegate> V4L2CaptureDelegate::GetWeakPtr() {
+  return weak_factory_.GetWeakPtr();
+}
+
 V4L2CaptureDelegate::~V4L2CaptureDelegate() {}
 
 bool V4L2CaptureDelegate::MapAndQueueBuffer(int index) {
   v4l2_buffer buffer;
   FillV4L2Buffer(&buffer, index);
 
   if (HANDLE_EINTR(ioctl(device_fd_.get(), VIDIOC_QUERYBUF, &buffer)) < 0) {
     DLOG(ERROR) << "Error querying status of a MMAP V4L2 buffer";
     return false;
   }
@@ skipping 86 matching lines @@
         cb.Run(std::move(blob));
     }
 
     if (HANDLE_EINTR(ioctl(device_fd_.get(), VIDIOC_QBUF, &buffer)) < 0) {
       SetErrorState(FROM_HERE, "Failed to enqueue capture buffer");
       return;
     }
   }
 
   v4l2_task_runner_->PostTask(
-      FROM_HERE, base::Bind(&V4L2CaptureDelegate::DoCapture, this));
+      FROM_HERE, base::Bind(&V4L2CaptureDelegate::DoCapture, GetWeakPtr()));
 }
 
 void V4L2CaptureDelegate::SetErrorState(
     const tracked_objects::Location& from_here,
     const std::string& reason) {
   DCHECK(v4l2_task_runner_->BelongsToCurrentThread());
   is_capturing_ = false;
   client_->OnError(from_here, reason);
 }
 
@@ skipping 16 matching lines @@
     DLOG(ERROR) << "Error mmap()ing a V4L2 buffer into userspace";
     return false;
   }
   start_ = static_cast<uint8_t*>(start);
   length_ = buffer.length;
   payload_size_ = 0;
   return true;
 }
 
 }  // namespace media