With this commit preliminary audio support in VirtualBox is enabled.
The backend supports playback as well as recording sounds from within
a guest VM. Depending on how the guest configures the device model
the audio output may sound disorted. If the guest uses buffers that
are too small, i.e., 10 ms or less, frequent buffer underruns will
occure.
To get this low-latency one has also to increase vbox' update hz
to 200 (i.e., 5ms).
Fixes#1647.
Currently, libc_noux includes the 'base/src/base/env/platform_env.h' file
to be able to reinitialize the environment using the 'Platform_env'
interface. For base-linux, a special version of this file exists and the
inclusion of the generic version in libc_noux causes GCC 4.9 to make wrong
assumptions about the memory layout of the 'Env' object returned by
'Genode::env()'.
This commit moves the reinitialization functions to the 'Env' interface to
avoid the need to include the 'platform_env.h' file in libc_noux.
Fixes#1510
The information about connected devices is obtained from a ROM file named
'usb_devices', which is supposed to contain a device list as in the device
report generated by the USB driver (see issue #1506).
A policy for 'report_rom' would look like:
<policy label="vbox -> usb_devices" report="usb_drv -> devices"/>
If the 'usb_devices' ROM file is not available, a warning message gets
printed and VirtualBox continues without USB pass-through support.
The devices to be passed-through need to have a matching device filter in
the '.vbox' file. Example:
<USB>
<DeviceFilters>
<DeviceFilter name="USB Scanner" active="true" vendorId="04a9"
productId="2220" remote="0"/>
</DeviceFilters>
</USB>
The feature was tested with HID devices (mouse, keyboard) and a flatbed
scanner. Mass storage devices didn't work correctly (they also didn't work
with VirtualBox on Linux without the closed-source extension pack).
It should be made sure that the USB driver does not try to control the
devices to be passed-through itself, for example, when passing-through
a HID device, the '<hid/>' config option should not be set.
Fixes#1507
This patch changes the top-level directory layout as a preparatory
step for improving the tools for managing 3rd-party source codes.
The rationale is described in the issue referenced below.
Issue #1082