Implementation of a new jtag remote_bitbang driver.

The driver sends ascii encoded bitbang commands over unix sockets or TCP to
another process. This driver is useful for debugging software running on
processors which are being simulated.

doc/openocd.texi

@@ -2321,6 +2321,43 @@ ft2232_vid_pid 0x0403 0xbdc8
 @end example
 @end deffn
 
+@deffn {Interface Driver} {remote_bitbang}
+Drive JTAG from a remote process. This sets up a UNIX or TCP socket connection
+with a remote process and sends ASCII encoded bitbang requests to that process
+instead of directly driving JTAG.
+
+The remote_bitbang driver is useful for debugging software running on
+processors which are being simulated.
+
+@deffn {Config Command} {remote_bitbang_port} number
+Specifies the TCP port of the remote process to connect to or 0 to use UNIX
+sockets instead of TCP.
+@end deffn
+
+@deffn {Config Command} {remote_bitbang_host} hostname
+Specifies the hostname of the remote process to connect to using TCP, or the
+name of the UNIX socket to use if remote_bitbang_port is 0.
+@end deffn
+
+For example, to connect remotely via TCP to the host foobar you might have
+something like:
+
+@example
+interface remote_bitbang
+remote_bitbang_port 3335
+remote_bitbang_host foobar
+@end example
+
+To connect to another process running locally via UNIX sockets with socket
+named mysocket:
+
+@example
+interface remote_bitbang
+remote_bitbang_port 0
+remote_bitbang_host mysocket
+@end example
+@end deffn
+
 @deffn {Interface Driver} {usb_blaster}
 USB JTAG/USB-Blaster compatibles over one of the userspace libraries
 for FTDI chips.  These interfaces have several commands, used to