The Tor Browser: dom/system/gonk/VolumeCommand.h@b8a032363ba2 (annotated)

dom/system/gonk/VolumeCommand.h@b8a032363ba2 (annotated)

dom/system/gonk/VolumeCommand.h

Thu, 22 Jan 2015 13:21:57 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Thu, 22 Jan 2015 13:21:57 +0100
branch: TOR_BUG_9701
changeset 15: b8a032363ba2
permissions: -rw-r--r--

Incorporate requested changes from Mozilla in review:
https://bugzilla.mozilla.org/show_bug.cgi?id=1123480#c6

 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
  * You can obtain one at http://mozilla.org/MPL/2.0/. */
 #ifndef mozilla_system_volumecommand_h__
 #define mozilla_system_volumecommand_h__
 #include "nsString.h"
 #include "nsISupportsImpl.h"
 #include "mozilla/RefPtr.h"
 #include <algorithm>
 #include <vold/ResponseCode.h>
 namespace mozilla {
 namespace system {
 class Volume;
 class VolumeCommand;
 /***************************************************************************
 *
 *   The VolumeResponseCallback class is an abstract base class. The ResponseReceived
 *   method will be called for each response received.
 *
 *   Depending on the command, there may be multiple responses for the
 *   command. Done() will return true if this is the last response.
 *
 *   The responses from vold are all of the form:
 *
 *     <ResponseCode> <String>
 *
 *   Valid Response codes can be found in the vold/ResponseCode.h header.
 *
 ***************************************************************************/
 class VolumeResponseCallback
 {
 protected:
   virtual ~VolumeResponseCallback() {}
 public:
   NS_INLINE_DECL_REFCOUNTING(VolumeResponseCallback)
   VolumeResponseCallback()
     : mResponseCode(0), mPending(false) {}
   bool Done() const
   {
     // Response codes from the 200, 400, and 500 series all indicated that
     // the command has completed.
     return (mResponseCode >= ResponseCode::CommandOkay)
         && (mResponseCode < ResponseCode::UnsolicitedInformational);
   }
   bool WasSuccessful() const
   {
     return mResponseCode == ResponseCode::CommandOkay;
   }
   bool              IsPending() const     { return mPending; }
   int               ResponseCode() const  { return mResponseCode; }
   const nsCString  &ResponseStr() const   { return mResponseStr; }
 protected:
   virtual void ResponseReceived(const VolumeCommand* aCommand) = 0;
 private:
   friend  class VolumeCommand;  // Calls HandleResponse and SetPending
   void HandleResponse(const VolumeCommand* aCommand,
                       int aResponseCode,
                       nsACString& aResponseStr)
   {
     mResponseCode = aResponseCode;
 #if ANDROID_VERSION >= 17
     // There's a sequence number here that we don't care about
     // We expect it to be 0. See VolumeCommand::SetCmd
     mResponseStr = Substring(aResponseStr, 2);
 #else
     mResponseStr = aResponseStr;
 #endif
     if (mResponseCode >= ResponseCode::CommandOkay) {
       // This is a final response.
       mPending = false;
     }
     ResponseReceived(aCommand);
   }
   void SetPending(bool aPending) { mPending = aPending; }
   int       mResponseCode;  // The response code parsed from vold
   nsCString mResponseStr;   // The rest of the line.
   bool      mPending;       // Waiting for response?
 };
 /***************************************************************************
 *
 *   The VolumeCommand class is an abstract base class used to encapsulate
 *   volume commands send to vold.
 *
 *   See VolumeManager.h for a list of the volume commands.
 *
 *   Commands sent to vold need an explicit null character so we add one
 *   to the command to ensure that it's included in the length.
 *
 *   All of these commands are asynchronous in nature, and the
 *   ResponseReceived callback will be called when a response is available.
 *
 ***************************************************************************/
 class VolumeCommand
 {
 protected:
   virtual ~VolumeCommand() {}
 public:
   NS_INLINE_DECL_REFCOUNTING(VolumeCommand)
   VolumeCommand(VolumeResponseCallback* aCallback)
     : mBytesConsumed(0),
       mCallback(aCallback)
   {
     SetCmd(NS_LITERAL_CSTRING(""));
   }
   VolumeCommand(const nsACString& aCommand, VolumeResponseCallback* aCallback)
     : mBytesConsumed(0),
       mCallback(aCallback)
   {
     SetCmd(aCommand);
   }
   void SetCmd(const nsACString& aCommand)
   {
     mCmd.Truncate();
 #if ANDROID_VERSION >= 17
     // JB requires a sequence number at the beginning of messages.
     // It doesn't matter what we use, so we use 0.
     mCmd = "0 ";
 #endif
     mCmd.Append(aCommand);
     // Add a null character. We want this to be included in the length since
     // vold uses it to determine the end of the command.
     mCmd.Append('\0');
   }
   const char* CmdStr() const    { return mCmd.get(); }
   const char* Data() const      { return mCmd.Data() + mBytesConsumed; }
   size_t BytesConsumed() const  { return mBytesConsumed; }
   size_t BytesRemaining() const
   {
     return mCmd.Length() - std::min(mCmd.Length(), mBytesConsumed);
   }
   void ConsumeBytes(size_t aNumBytes)
   {
     mBytesConsumed += std::min(BytesRemaining(), aNumBytes);
   }
 private:
   friend class VolumeManager;   // Calls SetPending & HandleResponse
   void SetPending(bool aPending)
   {
     if (mCallback) {
       mCallback->SetPending(aPending);
     }
   }
   void HandleResponse(int aResponseCode, nsACString& aResponseStr)
   {
     if (mCallback) {
       mCallback->HandleResponse(this, aResponseCode, aResponseStr);
     }
   }
   nsCString mCmd;           // Command being sent
   size_t    mBytesConsumed; // How many bytes have been sent
   // Called when a response to the command is received.
   RefPtr<VolumeResponseCallback>  mCallback;
 };
 class VolumeActionCommand : public VolumeCommand
 {
 public:
   VolumeActionCommand(Volume* aVolume, const char* aAction,
                       const char* aExtraArgs, VolumeResponseCallback* aCallback);
 private:
   RefPtr<Volume>  mVolume;
 };
 class VolumeListCommand : public VolumeCommand
 {
 public:
   VolumeListCommand(VolumeResponseCallback* aCallback);
 };
 } // system
 } // mozilla
 #endif  // mozilla_system_volumecommand_h__

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dom/system/gonk/VolumeCommand.h@b8a032363ba2 (annotated)

dom/system/gonk/VolumeCommand.h