base/services/audiosrv/audiosrv.txt

   1 ReactOS Audio Service (audiosrv.exe)
   2 ====================================
   3
   4 This is intended to operate in a similar manner to how the Windows Audio
   5 Service does.
   6
   7 NOTE: The service filename is audiosrv.dll on Windows XP. This shouldn't
   8 have any impact on functionality.
   9
  10 AudioSrv on Windows creates a mapped file at:
  11 Global\mmGlobalPnpInfo
  12
  13 The ReactOS audio device list lives at:
  14 Global\AudioDeviceList
  15
  16 This file appears to contain a list of devices that WinMM accesses and
  17 subsequently passes to wdmaud.drv
  18
  19 It is not necessary to duplicate the exact structure of this mapped
  20 file, since it appears to only be used internally by Windows components.
  21
  22 The ROS Audio Service (RosAudioSrv) is intended to be able to run
  23 alongside the Windows Audio Service on XP/Vista, so it should be
  24 possible to test in a "known working environment" ;)
  25
  26 It will create a mutex, to:
  27 1) Allow synchronization when accessing the device list
  28 2) Provide a simple method of identifying if RosAudioSrv is running
  29
  30 (It might be worth using an event to notify WinMM when things are
  31 happening?)
  32
  33 The intention is to make RosAudioSrv receive PnP notifications for
  34 relevant audio devices, and also let AudioSrv in Windows do this. Then
  35 it should be possible to create a small application that imitates
  36 WinMM's actions :)
  37
  38
  39 Current Status
  40 ==============
  41
  42 AudioSrv registers for device notifications and obtains a list of the
  43 current audio devices in the system (devices registered against the
  44 KSCATEGORY_AUDIO interface).
  45
  46 ReactOS does not currently have RegisterDeviceNotification implemented,
  47 so for the moment this service considers the failure of this API call
  48 to be non-fatal and will proceed without device event notification. This
  49 behaviour will be amended in a future revision (ie once this API call
  50 is implemented!)
  51
  52
  53 Testing the Service
  54 ===================
  55
  56 The service can be installed on Windows XP (possibly also Vista) like so:
  57 sc create RosAudioSrv <path to audiosrv.exe>
  58 net start RosAudioSrv
  59
  60 ...and can be removed like so:
  61 net stop RosAudioSrv
  62 sc delete RosAudioSrv
  63
  64 You can view a list of the currently available devices (device list is
  65 identical to the one offered by Windows' own AudioSrv) by running
  66 my READER.EXE test utility, available in the following package:
  67
  68 http://stuff.silverblade.co.uk/reactos/sharedlist.tar.gz
  69
  70 That's all for now, folks ;)
  71
  72
  73 Andrew Greenwood
  74 September 2007