CVS port to VMS

DISCLAIMER: This port must be considered experimental.  Although
previous versions have been in use at one large site since about
October, 1995, and the port is believed to be quite usable, various
VMS-specific quirks are known and the port cannot be considered as
mature as the ports to, say, Windows NT or unix.  As always, future
progress of this port will depend on volunteer and customer interest.

This port is of the CVS client only.  Or in other words, the port
implements the full set of CVS commands, but cannot access
repositories located on the local machine.  The repository must live
on another machine (a Unix box) which runs a complete port of CVS.

Most (all?) work to date has been done on OpenVMS/AXP 6.2.  Other VMS
variants might work too.

Provided that both your client and your server are recent (for
example, CVS 1.9.27 or later), you shouldn't need GNU patch or any
other executables other than CVS.EXE.

Please send bug reports to bug-cvs@nongnu.org.

As of CVS 1.5.something, this port passed most of the tests in
[.src]sanity.sh.  I say "most" because some tests to not apply to the
CVS client.  The tests were run by hand because the VMS POSIX shell
was incapable of running the script.  The tests that sanity.sh
provides are not conclusive but at least provides some assurance that
the client is usable.

To compile, you will need DEC C (CC), DEC UCX, and of course DCL
installed on your machine.  Just type "@build" in the top level
directory.  This will build the sources in each subdirectory, and link
the executable [.src]cvs.exe

Copy the executable to an appropriate directory, and define the symbol "CVS"
in a .COM file which everyone running CVS will need to run.  Here's an example
of what needs to be done.

$ CVS :== $YOUR_DEVICE:[YOUR.DIRECTORY.CVS]CVS.EXE

Accessing a remote repository can happen in several ways.

1. pserver
2. rsh - privileged (default)
3. rsh - unprivileged (on VMS side)

Here's how to do each of the above:

-------------------------------------------------------------------------------
1.  pserver.  This is the preferred way.  It works just as it is
documented in the CVS manual (see the README file in the CVS
distribution for more information on the manual).

-------------------------------------------------------------------------------
2. Using CVS internal rsh support (privileged)

VMS's RSH is unusable for CVS's purposes (that is, the one in UCX.
Don't know about Multinet).  However, there is code within CVS to
emulate RSH for purposes of contacting a CVS server "in the usual way"
via rshd.  Unfortunately, this requires the VMS CVS client to be
installed with OPER privilege, by your system administrator.

RSH uses privileged ports and trusted software/hosts to determine
which user on the client side is trying to connect.  Part of this
security is due to the fact that on VMS or UNIX, a non privileged
process is not permitted to bind a socket to a privileged port.

If rshd receives a connection on a non-privileged port, the connection is
immediately aborted.  Only connections arriving from a privileged port will
be authenticated and served.  The CVS client will therefore need privileges
under VMS to produce such a connection.

*** Please note that no careful examination has been done of the security
    implications of installing CVS with the OPER privilege.  If some hole
    exists, then by doing so, you will enable users who are already on
    your system to gain unauthorized privileges ***

-------------------------------------------------------------------------------
3. Using CVS internal rsh support (non-privileged)

There is a workaround, but this is one case where I think the cure is worse
than the disease.  If you patch an rshd to not care that the RSH originating
port is "non-privileged", the CVS VMS client will allow you to define the
logical CVS_RCMD_PORT to the port number where this patched rshd will be
listening.  I leave the talk of patching rshd to the gentle reader and his/her
friendly system administrator.

If I put an entry in my /etc/services file:

cvs_rcmd            4381/tcp        cvs_rcmd

And add a line to /etc/inetd.conf, then restart inetd via "kill -1"

cvs_rcmd  stream  tcp  nowait root /usr/sbin/tcpd  /usr/local/sbin/cvs_rcmd

On the VMS side, you will have to do this:

$ define CVS_RCMD_PORT 4381

Then run CVS in the "usual way".

Note that the patched rshd will need to be invoked via inetd as root, so it can
authenticate and _become_ the intended user, the same as the regular rshd.

***Please note that you will be installing a security hole by doing this.***

Please also note that this security hole is no larger than allowing a
Macintosh, PC (OS/2, NT, etc.) to have it's hostname in any .rhosts file,
as any user can create a privileged socket without authentication, under these
environments.  In fact, existing ports of CVS to these environment use this
to their advantage.

-------------------------------------------------------------------------------
Wildcard expansion is not yet implemented (i.e. CVS COMMIT *.c won't
work.)  I think that expand_wild should be calling lib$findfile
(util.c in gzip is said to provide an example), but noone has gotten
around to implementing this.

Log messages must be entered on the command line using -m or -F.  You
can use -e or define the logical EDITOR to cause CVS to try other
editors (TPU.EXE or any other editor which wants DCL command parsing
will not work) if you want to test what's available on your system.  I
haven't tested this, but if you install vi or emacs, chances are it
will probably work.  Just make sure the .EXE files are in a directory
listed in VAXC$PATH (is this a typo for DCL$PATH?  Also, will a
logical name work?).  If someone gets around to implementing it, we
should probably be using the callable editors (e.g. TPU$TPU), although
of course we also need interface(s) which are not locked into any
particular editors.

----------------------------------------

Notes regarding compiling on VAX/VMS 6.2 (not Alpha) (These are items
which hopefully will have cleaner solutions in the future, but here is
how to get around them for now):

* Need to compile lib/getdate.c with vaxc instead of decc to avoid a
compiler bugcheck.  Therefore one must add SYS$LIBRARY:VAXCRTL/LIBRARY
to the link.

* In src/ignore.c, change lstat to stat.  In vms/filesubr.c, change
"#ifdef S_ISLNK" to "#if 0".

* Ignore the warnings in vms/vmsmunch.c; the system include file
declares something as an int when it should be void *.  Not *our*
fault!

* Remove the #define's of mode_t in vms/vms.h and pid_t in vms/pwd.h.
Add "#include <sys/types.h>" in vms/pwd.h.

Credits:

Initial VMS port by Benjamin J. Lee <benjamin@cyclic.com>, Cyclic
Software, October 1, 1995 (Update March 1, 1996).