Change webcamPrivate.set/get/reset to async APIs.

extensions/browser/api/webcam_private/v4l2_webcam.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 "extensions/browser/api/webcam_private/v4l2_webcam.h"
 
 #include <fcntl.h>
 #include <linux/uvcvideo.h>
 #include <linux/videodev2.h>
 #include <stdio.h>
@@ skipping 67 matching lines @@
 bool V4L2Webcam::GetWebcamParameter(int fd, uint32_t control_id, int* value) {
   struct v4l2_control v4l2_ctrl = {control_id};
 
   if (HANDLE_EINTR(ioctl(fd, VIDIOC_G_CTRL, &v4l2_ctrl)))
     return false;
 
   *value = v4l2_ctrl.value;
   return true;
 }
 
-void V4L2Webcam::Reset(bool pan, bool tilt, bool zoom) {
-  if (pan || tilt) {
-    if (EnsureLogitechCommandsMapped()) {
-      SetWebcamParameter(fd_.get(), V4L2_CID_PANTILT_CMD,
-                         kLogitechMenuIndexGoHome);
-    } else {
-      if (pan) {
-        struct v4l2_control v4l2_ctrl = {V4L2_CID_PAN_RESET};
-        HANDLE_EINTR(ioctl(fd_.get(), VIDIOC_S_CTRL, &v4l2_ctrl));
-      }
-
-      if (tilt) {
-        struct v4l2_control v4l2_ctrl = {V4L2_CID_TILT_RESET};
-        HANDLE_EINTR(ioctl(fd_.get(), VIDIOC_S_CTRL, &v4l2_ctrl));
-      }
-    }
-  }
-
-  if (zoom) {
-    const int kDefaultZoom = 100;
-    SetWebcamParameter(fd_.get(), V4L2_CID_ZOOM_ABSOLUTE, kDefaultZoom);
-  }
+void V4L2Webcam::GetPan(const GetPTZCompleteCallback& callback) {
+  int value = 0;
+  bool success = GetWebcamParameter(fd_.get(), V4L2_CID_PAN_ABSOLUTE, &value);
+  callback.Run(success, value);
 }
 
-bool V4L2Webcam::GetPan(int* value) {
-  return GetWebcamParameter(fd_.get(), V4L2_CID_PAN_ABSOLUTE, value);
+void V4L2Webcam::GetTilt(const GetPTZCompleteCallback& callback) {
+  int value = 0;
+  bool success = GetWebcamParameter(fd_.get(), V4L2_CID_TILT_ABSOLUTE, &value);
+  callback.Run(success, value);
 }
 
-bool V4L2Webcam::GetTilt(int* value) {
-  return GetWebcamParameter(fd_.get(), V4L2_CID_TILT_ABSOLUTE, value);
+void V4L2Webcam::GetZoom(const GetPTZCompleteCallback& callback) {
+  int value = 0;
+  bool success = GetWebcamParameter(fd_.get(), V4L2_CID_ZOOM_ABSOLUTE, &value);
+  callback.Run(success, value);
 }
 
-bool V4L2Webcam::GetZoom(int* value) {
-  return GetWebcamParameter(fd_.get(), V4L2_CID_ZOOM_ABSOLUTE, value);
+void V4L2Webcam::SetPan(int value, const SetPTZCompleteCallback& callback) {
+  callback.Run(SetWebcamParameter(fd_.get(), V4L2_CID_PAN_ABSOLUTE, value));
 }
 
-bool V4L2Webcam::SetPan(int value) {
-  return SetWebcamParameter(fd_.get(), V4L2_CID_PAN_ABSOLUTE, value);
+void V4L2Webcam::SetTilt(int value, const SetPTZCompleteCallback& callback) {
+  callback.Run(SetWebcamParameter(fd_.get(), V4L2_CID_TILT_ABSOLUTE, value));
 }
 
-bool V4L2Webcam::SetTilt(int value) {
-  return SetWebcamParameter(fd_.get(), V4L2_CID_TILT_ABSOLUTE, value);
+void V4L2Webcam::SetZoom(int value, const SetPTZCompleteCallback& callback) {
+  callback.Run(SetWebcamParameter(fd_.get(), V4L2_CID_ZOOM_ABSOLUTE, value));
 }
 
-bool V4L2Webcam::SetZoom(int value) {
-  return SetWebcamParameter(fd_.get(), V4L2_CID_ZOOM_ABSOLUTE, value);
-}
-
-bool V4L2Webcam::SetPanDirection(PanDirection direction) {
+void V4L2Webcam::SetPanDirection(PanDirection direction,
+                                 const SetPTZCompleteCallback& callback) {
   int direction_value = 0;
   switch (direction) {
     case PAN_STOP:
       direction_value = 0;
       break;
 
     case PAN_RIGHT:
       direction_value = 1;
       break;
 
     case PAN_LEFT:
       direction_value = -1;
       break;
   }
-  return SetWebcamParameter(fd_.get(), V4L2_CID_PAN_SPEED, direction_value);
+  callback.Run(
+      SetWebcamParameter(fd_.get(), V4L2_CID_PAN_SPEED, direction_value));
 }
 
-bool V4L2Webcam::SetTiltDirection(TiltDirection direction) {
+void V4L2Webcam::SetTiltDirection(TiltDirection direction,
+                                  const SetPTZCompleteCallback& callback) {
   int direction_value = 0;
   switch (direction) {
     case TILT_STOP:
       direction_value = 0;
       break;
 
     case TILT_UP:
       direction_value = 1;
       break;
 
     case TILT_DOWN:
       direction_value = -1;
       break;
   }
-  return SetWebcamParameter(fd_.get(), V4L2_CID_TILT_SPEED, direction_value);
+  callback.Run(
+      SetWebcamParameter(fd_.get(), V4L2_CID_TILT_SPEED, direction_value));
+}
+
+void V4L2Webcam::Reset(bool pan,
+                       bool tilt,
+                       bool zoom,
+                       const SetPTZCompleteCallback& callback) {
+  bool success = true;
+  if (pan || tilt) {
+    if (EnsureLogitechCommandsMapped()) {
+      success &= SetWebcamParameter(fd_.get(), V4L2_CID_PANTILT_CMD,

[Zachary Kuznia, 2015/08/19 20:49:44]

It's not a good idea to use bitwise AND to combine bools.  Please just set
success to false fail immediately when a call fails.

[xdai1, 2015/08/21 22:57:02]

Done.

+                                    kLogitechMenuIndexGoHome);
+    } else {
+      if (pan) {
+        struct v4l2_control v4l2_ctrl = {V4L2_CID_PAN_RESET};
+        success &= HANDLE_EINTR(ioctl(fd_.get(), VIDIOC_S_CTRL, &v4l2_ctrl));
+      }
+
+      if (tilt) {
+        struct v4l2_control v4l2_ctrl = {V4L2_CID_TILT_RESET};
+        success &= HANDLE_EINTR(ioctl(fd_.get(), VIDIOC_S_CTRL, &v4l2_ctrl));
+      }
+    }
+  }
+
+  if (zoom) {
+    const int kDefaultZoom = 100;
+    success &=
+        SetWebcamParameter(fd_.get(), V4L2_CID_ZOOM_ABSOLUTE, kDefaultZoom);
+  }
+
+  callback.Run(success);
 }
 
 }  // namespace extensions