Add use_v4lplugin flag to enable v4l2 library

content/common/gpu/media/exynos_v4l2_video_device.cc

 // Copyright 2014 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 <fcntl.h>
 #include <libdrm/drm_fourcc.h>
 #include <linux/videodev2.h>
 #include <poll.h>
 #include <sys/eventfd.h>
 #include <sys/ioctl.h>
 #include <sys/mman.h>
 
 #include "base/debug/trace_event.h"
 #include "base/files/scoped_file.h"
 #include "base/posix/eintr_wrapper.h"
 #include "content/common/gpu/media/exynos_v4l2_video_device.h"
 #include "ui/gl/gl_bindings.h"
 
+#ifdef USE_LIBV4L2
+#include <libv4l2.h>

[Pawel Osciak, 2014/11/19 11:05:22]

Please instead "third_party/v4l-utils/lib/include/libv4l2.h"

[henryhsu, 2014/11/20 05:11:58]

Done.

+#include "content/common/gpu/media/v4l2_stubs.h"
+
+using content_common_gpu_media::kModuleV4l2;
+using content_common_gpu_media::InitializeStubs;
+using content_common_gpu_media::StubPathMap;
+
+static const base::FilePath::CharType kV4l2Lib[] =
+    FILE_PATH_LITERAL("libv4l2.so");
+#else
+#define v4l2_close close
+#define v4l2_ioctl ioctl
+#endif
+
 namespace content {
 
 namespace {
 const char kDecoderDevice[] = "/dev/mfc-dec";
 const char kEncoderDevice[] = "/dev/mfc-enc";
 const char kImageProcessorDevice[] = "/dev/gsc1";
 }
 
 ExynosV4L2Device::ExynosV4L2Device(Type type)
     : type_(type),
       device_fd_(-1),
-      device_poll_interrupt_fd_(-1) {}
+      device_poll_interrupt_fd_(-1) {
+}
 
 ExynosV4L2Device::~ExynosV4L2Device() {
   if (device_poll_interrupt_fd_ != -1) {
     close(device_poll_interrupt_fd_);
     device_poll_interrupt_fd_ = -1;
   }
   if (device_fd_ != -1) {
-    close(device_fd_);
+    v4l2_close(device_fd_);
     device_fd_ = -1;
   }
 }
 
 int ExynosV4L2Device::Ioctl(int request, void* arg) {
-  return HANDLE_EINTR(ioctl(device_fd_, request, arg));
+  return HANDLE_EINTR(v4l2_ioctl(device_fd_, request, arg));
 }
 
 bool ExynosV4L2Device::Poll(bool poll_device, bool* event_pending) {
   struct pollfd pollfds[2];
   nfds_t nfds;
   int pollfd = -1;
 
   pollfds[0].fd = device_poll_interrupt_fd_;
   pollfds[0].events = POLLIN | POLLERR;
   nfds = 1;
@@ skipping 48 matching lines @@
     } else {
       DPLOG(ERROR) << "ClearDevicePollInterrupt(): read() failed";
       return false;
     }
   }
   return true;
 }
 
 bool ExynosV4L2Device::Initialize() {
   const char* device_path = NULL;
+  static bool v4l2_functions_initialized = PostSandboxInitialization();
+  if (!v4l2_functions_initialized) {
+    LOG(ERROR) << "Failed to initialize LIBV4L2 libs";
+    return false;
+  }
+
   switch (type_) {
     case kDecoder:
       device_path = kDecoderDevice;
       break;
     case kEncoder:
       device_path = kEncoderDevice;
       break;
     case kImageProcessor:
       device_path = kImageProcessorDevice;
       break;
   }
 
   DVLOG(2) << "Initialize(): opening device: " << device_path;
   // Open the video device.
   device_fd_ = HANDLE_EINTR(open(device_path, O_RDWR | O_NONBLOCK | O_CLOEXEC));
   if (device_fd_ == -1) {
     return false;
   }
+#ifdef USE_LIBV4L2
+  if (HANDLE_EINTR(v4l2_fd_open(device_fd_, V4L2_DISABLE_CONVERSION)) == -1) {
+    v4l2_close(device_fd_);
+    return false;
+  }
+#endif
 
   device_poll_interrupt_fd_ = eventfd(0, EFD_NONBLOCK | EFD_CLOEXEC);
   if (device_poll_interrupt_fd_ == -1) {
     return false;
   }
   return true;
 }
 
 EGLImageKHR ExynosV4L2Device::CreateEGLImage(EGLDisplay egl_display,
                                              EGLContext /* egl_context */,
@@ skipping 59 matching lines @@
   return V4L2_PIX_FMT_NV12M;
 }
 
 uint32 ExynosV4L2Device::PreferredOutputFormat() {
   // TODO(posciak): We should support "dontcare" returns here once we
   // implement proper handling (fallback, negotiation) for this in users.
   CHECK_EQ(type_, kDecoder);
   return V4L2_PIX_FMT_NV12M;
 }
 
+// static
+bool ExynosV4L2Device::PostSandboxInitialization() {
+#ifdef USE_LIBV4L2
+  StubPathMap paths;
+  paths[kModuleV4l2].push_back(kV4l2Lib);
+
+  return InitializeStubs(paths);
+#else
+  return true;
+#endif
+}
+
 }  //  namespace content