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

media/video/capture/linux/v4l2_capture_delegate_single_plane.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/video/capture/linux/v4l2_capture_delegate_single_plane.h"
+
+#include <sys/mman.h>
+
+namespace media {
+
+scoped_refptr<V4L2VideoCaptureDelegate::BufferTracker>
+V4L2CaptureDelegateSinglePlane::CreateBufferTracker() {
+  return make_scoped_refptr(new BufferTrackerSPlane());
+}
+
+bool V4L2CaptureDelegateSinglePlane::FillV4L2Format(
+    v4l2_format* format,
+    uint32_t width,
+    uint32_t height,
+    uint32_t pixelformat_fourcc) {
+  format->fmt.pix.width = width;
+  format->fmt.pix.height = height;
+  format->fmt.pix.pixelformat = pixelformat_fourcc;
+  return true;
+}
+
+void V4L2CaptureDelegateSinglePlane::FinishFillingV4L2Buffer(
+    v4l2_buffer* buffer) const {
+  buffer->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+}
+
+void V4L2CaptureDelegateSinglePlane::SendBuffer(
+    const scoped_refptr<BufferTracker>& buffer_tracker) {
+  client()->OnIncomingCapturedData(
+      buffer_tracker->GetPlaneStart(0),
+      buffer_tracker->GetPlaneLength(0),
+      capture_format(),
+      rotation(),
+      base::TimeTicks::Now());
+}
+
+bool V4L2CaptureDelegateSinglePlane::BufferTrackerSPlane::Init(
+    int fd,
+    const v4l2_buffer& buffer) {
+  // Some devices require mmap() to be called with both READ and WRITE.
+  // See http://crbug.com/178582.
+  void* const start = mmap(NULL, buffer.length, PROT_READ | PROT_WRITE,
+                           MAP_SHARED, fd, buffer.m.offset);
+  if (start == MAP_FAILED) {
+    DLOG(ERROR) << "Error mmap()ing a V4L2 buffer into userspace";
+    return false;
+  }
+  AddMmapedPlane(start, buffer.length);
+  return true;
+}
+
+}  // namespace media