Rewrite the SCO socket implementation to be more robust.
This code presents a socket interface for SCO connections. Like the
previous implementation, it does not support sending/receiving data
over the sockets; rather, it only provides a mechanism to establish
and tear down connections. It is assumed that all SCO data routing is
done out-of-band over PCM/I2S.
A SCO socket is represented internally by a file descriptor and SCO
handle. The file descriptor is one end of a socketpair (the other
end is sent to the Java process) and the SCO handle represents a
server (listening) or client (connecting) socket owned by the BTM
layer of the stack.
The most notable implementation detail is that, unlike typical
sockets, listening SCO sockets get "upgraded" when a connection is
established. In other words, a SCO handle for a listening socket
turns into a handle for a connected socket. To present a BSD-style
API to Java processes, we play a trick: when a listening socket gets
upgraded, we create a new listening SCO socket and reassociate the
SCO handle for the two sockets. The reassociation allows the Java
process to continue listening for new incoming SCO connections on
the same file descriptor.
4 files changed