Log Message:
Import alsa-lib version 1.0.18.

The Advanced Linux Sound Architecture (ALSA) provides audio and MIDI
functionality to the Linux operating system. ALSA has the following
significant features:

    * Efficient support for all types of audio interfaces, from consumer sound
      cards to professional multichannel audio interfaces.
    * Fully modularized sound drivers.
    * SMP and thread-safe design.
    * User space library (alsa-lib) to simplify application programming and
      provide higher level functionality.
    * Support for the older Open Sound System (OSS) API, providing binary
      compatibility for most OSS programs.