<Sound Dev> [9] Review Request: 8135160 Endless Loop in RiffReader

[Sergey Bylokhov]

Hello.
Please review the fix for jdk9.

     While working on some bugs in javasound, I found one issue which 
can cause an endless loop for some specific audio file. The bug is 
located in the com.sun.media.sound.RIFFReader.skipBytes() method, which 
incorrectly assumes that Inputstrem.skip() method should return -1 at 
the end of the stream. Note that the specification of the read() method 
has this assumption.

The current implementation of the skip method has a loop which stops 
when the necessary amount of bytes are skipped or the -1 is returned.

In the fix I change implementation of this loop:
  - The check for the negative value is removed, because such checks are 
not specified.
  - The check for the zero is enhanced using read() method. This is 
necessary, because the specification of the skip method mention that the 
zero can be returned if EOF occurred or nothing was skipped for some 
other reason and the user should try again.
  - Note that the skip method can return more bytes than was requested 
if EOF occurred(at least this part of spec is unclear???), the check for 
this is also added(otherwise the avail variable can became negative).

One new test was added, it was used as initial reproducer. One existed 
test was updated.

Bug: https://bugs.openjdk.java.net/browse/JDK-8135160
Webrev can be found at: http://cr.openjdk.java.net/~serb/8135160/webrev.00


ps: Note that two review requests still active in the javasound:
 
http://mail.openjdk.java.net/pipermail/sound-dev/2015-September/000330.html
 
http://mail.openjdk.java.net/pipermail/sound-dev/2015-September/000332.html


-- 
Best regards, Sergey.