Retrofitting RFSV 16 to Fritz Elfert's plptools
===============================================

These notes updated 21/10/99


I started modifying Fritz' plptools-0.3 with the intention of adding back the
RFSV16 support. Fritz then released 0.4, and so I re-patched 0.4, and did lots
more work, and merged in some patches from Pete Bentley.

The result is this, plptools-0.4-mjg<x>. 

When it's finished, hopefully Fritz will merge it into the next official
release.

Release Dates:
plptools-0.4-mjg1 on 23/09/99
plptools-0.4-mjg2 on 04/10/99
plptools-0.4-mjg3 on 07/10/99
plptools-0.4-mjg4 on 10/10/99
plptools-0.4-mjg5 on 21/10/99 (+ patch against 0.4 original)

The changes to plptools-0.4 are:
* Now detects which version of the NCP protocol is in use, and records this:
  this is how we detect whether the Psion is a Series 3 or Series 5.
* Makefiles updated to include the rfsv16 stuff, the rfsv base class, and the
  rfsvfactory object.
* Instantiates either an RFSV32 or RFSV16 object to handle the file server
  requests, based on the protocol version returned by the INFO command above.
  There is an rfsvfactory object to make this easier in client programs. 
  This is used in plpftp and plpnfsd.  This will obtain the NCP version number
  over the socket, by announcing itself as "NCP$INFO.*". The correct RFSV class
  will further announce itself as SYS$RFSV.* - this is stored in connectName.
  RFSV objects have an opAttr method to output a correct attributes flag for each
  protocol. 
* Added --with-drive and --with-basedir to the configure.in script, and
  include/defs.h.in. These are used in RFSV16, and plpftp now uses these,
  instead of the DEFAULT_DRIVE AND DEFAULT_BASE_DIRECTORY of ftp.h
* ncpd/packet.h: verbose is now a short int, to allow packet debugging.
* Pete Bentley's changes. Fixes bogus definition of usleep(); plpftp compiles in
  the absence of libreadline and libhistory; accept 3rd parameter in ppsocket is
  signed not unsigned; -v all debugging option; (sun) link detection changes;
  new PKT_DEBUG_HANDSHAKE debug level added; correct termios.h include for
  Solaris; Solaris non-blocking fixes; move the fcntl for O_NONBLOCK; remove
  O_NONBLOCK where needed; set SO_REUSEADDR for ncpd.
* Peter Cherriman's "1 hour out" fix (doesn't work for me though... could be my
  PC clock)

Some things to do:
* Finish rfsv16.cc:
  fread, fwrite, fseek, copyFromPsion, copyToPsion, fsetsize, mktemp,
  fcreatefile, freplacefile, fopendir, fsetmtime

* Test everything with plpftp and plpnfsd.
* Remove read, write fully?
* Remove unused convertName method in plpftp/ftp.cc,h

Adding RFSV16 back is still a work in progress.... stay tuned!


Building plptools for use with a Psion 3
========================================
./configure --with-speed=19200 --with-serial=/dev/ttyS1 --with-drive=M:
# Or whatever port you use. I use ttyS1, since ttyS0 is my mouse.
# The default speed is 115200 bps, which is only for the Lucky S5 owners.
# The S3c can take speeds up to 57600, but my RS232 protocol analyser can't -
# your mileage may vary.
make
make install
plpftp
# NFS access not finished yet


Tip for use with a Psion 3
==========================
Turn the Psion's remote link on first, THEN run ncpd. 

Why this seems to help matters
------------------------------
This seems to ensure that the Psion will send a request for the LINK.* process,
which is what we must detect to allow other connections to the NCP daemon. It
seems there may be a strange bug when you start ncpd, THEN start the Psion link
- the link request/acknowledge messages are exchanged correctly, followed by
valid INFO/NCP Protocol Version messages - and then the Psion attempts to
connect to the PC's SYS$RFSV.* - IMHO, it should start by attempting to connect
to LINK.* 

Philip Proudman's plp_1.7 always receives the LINK.* connect request, as do
other protocol implementations. 

I haven't managed to work out why the Psion starts by sending a SYS$RFSV.*
connect request with plptools, and not with other implementations, but the above
work-around gets round it.


Troubleshooting
===============
Q. I can't build it on SuSE Linux.
A. You need the gppshare and libgpp packages. (Thanks to der.hans)


Acknowledgements
================
This couldn't have been written without pioneering investigations into the link
protocol by Olaf Flebbe, Michael Pieper, and others. Philip Proudman beat me to
producing a decent, working PLP stack (Thanks, Philip ;-) and Fritz Elfert did
some excellent merging of Rudolf Koenig's p3nfs.  Also thanks to the Majordomo
maintainers @geekstuff.co.uk, who host the linux-psion list.

Finally, the RFSV16 re-merge would still be in my In-tray if my wife Angela
hadn't been away for the week, leaving me to code, and fend for myself. 

Thanks to Pete Bentley for ideas on proxying, his patches, suggestions for
improvement, and a loan Series 5 for testing against.


Viola!
--
Matt Gumbley
matt@gumbley.demon.co.uk