AmigActive 21/AACD 21.iso/AACD/Programming/CVS/README.AMIGA

Text File | 2001-04-30 | 9.8 KB | 214 lines

CVS 1.11.1p1 Amiga port (29 April 2001)
=======================================

Introduction
------------
This is a somewhat rough port of GNU CVS 1.11.1p1, a version control system, which
allows you to keep old versions of files (usually source code), keep a log of
who, when, and why changes occurred, etc., like RCS or SCCS. It handles
multiple developers, multiple directories, triggers to enable/log/control
various operations, and can work over a wide area network. The following tasks
are not included; they can be done in conjunction with CVS but will tend to
require some script-writing and software other than CVS: bug-tracking, build
management (that is, make and make-like tools), and automated testing. (Quoted
from the CVS documentation.)

I call this a 'rough port' since it is not as polished as, say Heinz Wrobel's
excellent 'RCS' port. It does what it needs to do, but a few features are
sorely lacking, such as support for Amiga file protection bits and code to
communicate with CVS servers via secure channels (Kerberos, SSH). On the other
hand, however, you get everything, and perhaps more, you got with the previous
Amiga ports of CVS: this port does not require 'ixemul.library' to work and it
does not require an RCS installation as it is completely self contained. The
port also probably would win a price as the largest 'pure' executable; it can
be made resident.


What's in this package?
-----------------------
This distribution contains the Amiga port, the Amiga specific source code and
most of the original GNU CVS 1.11.1p1 distribution. 'Most' in this case means that
only the original source code has been omitted in order to keep the
distribution archive small; the documentation and support files are all
provided. The original source code can be downloaded from the Internet at
'ftp://ftp.cvshome.org/pub/cvs-1.11.1p1/cvs-1.11.1p1.tar.gz'. I have added two more
files which are converted from the original Unix man pages, namely 'cvs.1.man'
and 'cvs.5.man' whose sources can be found in the 'cvs-1.11.1p1/man' directory.


Installation
------------
Almost everything you need to get CVS up and running is contained in the
archive which also included the 'README.AMIGA' file you are currently reading.
And that means the 'cvs' executable. You will also need a working
'queue-handler' (the one that ships with Workbench 3.1 and beyond is,
unfortunately, broken) which can be found on Aminet (you can find the archive
at 'http://us.aminet.net/pub/aminet/util/sys/HWGQueue.lha'). A TCP/IP stack
like Miami or AmiTCP is supported but not strictly required: you can perfectly
well keep your CVS repository on your local machine. Since CVS may ask you to
edit the log entries associated with the files to store, you may want to
configure the 'EDITOR' environment variable. Last, but not least, you must set
up an environment variable which allows CVS to associate you with the changes
you made; this should be the 'USER', 'LOGUSER' or 'USERNAME' variable.

Most importantly, this port requires Kickstart 2.04 or higher.

Here is how you could set up CVS on your machine. We start by creating two
drawers on the 'Work:' volume:

   MakeDir Work:CVS-Root
   MakeDir Work:CVS-Home

Next, we add two lines to the 'S:User-Startup' file:

   Assign CVSHOME: Work:CVS-Home
   Path CVSHOME: Add

The CVS program will need to be copied:

   Copy cvs Work:CVS-Home CLONE

And the path to the CVS repository needs to be set:

   SetEnv CVSROOT :local:Work:CVS-Root
   Copy ENV:CVSROOT ENVARC:

Two environment variables need to be set up. Most importantly, CVS will need
your ID to write it into the log and revision files it creates. The Amiga port
will query three environment variables for that information, in the following
order: 'USER', 'LOGUSER' and 'USERNAME'. This means if the variable 'USER' is
not set, it will proceed to check whether 'LOGUSER' is set, and so forth. You
may have already configured these variables, but if you haven't, I suggest you
set up the 'LOGUSER' variable, like this:

   SetEnv LOGUSER <Your ID here>
   Copy ENV:LOGUSER ENVARC:

Note that <Your ID here> should be replaced by a mnemonic, nick name or short
name that must not contain any blank space characters.

You may want to configure the 'EDITOR' environment variable to invoke your
preferred text editor when CVS requests that log messages are added for an
update. If this variable is not set, CVS will default to invoke the 'Ed'
editor. This can be problematic if you have installed 'CygnusEd' whose 'Ed'
program detaches from the Shell that invoked it. When CVS invokes the editor,
it expects it to return only when the user has finished editing the respective
file. Here is an example configuration for CygnusEd:

   SetEnv EDITOR Ed -keepio

And here is one for TurboText:

   SetEnv EDITOR TTX WAIT

Don't forget to save the environment variable setting to make it permanent,
like this:

   Copy ENV:EDITOR ENVARC:

Finally, install the 'queue-handler' from Aminet and reboot your machine. When
the system is again up and running, initialize the CVS repository like this:

   cvs init

And that's all. Well, maybe you want to add a few default options to the
configuration file CVS reads upon startup. That file should be placed in the
'CVSHOME:' directory and called '.cvsrc':


Usage
-----
I personally found the default CVS documentation to be rather confusing. If
you don't know rather well what CVS is good for, the examples, the
terminology, all this doesn't seem to make great sense. My introduction to CVS
followed with Karl Fogel's book "Open Source Development with CVS" which
describes in compact form what CVS is and how it may be used. I suggest that
you consult the book (portions of which are available from 'www.coriolis.com')
and/or the CVS documentation (which has been included with this archive in the
'cvs-1.11/doc' drawer) for hints and ideas on how to use the program.

What many people fail to realize and what keeps them from using CVS in place
of the revision control system they have used for years is that you do not
need a networked CVS repository in order to use CVS. A local repository will
do. In fact, I switched over most of my current software development projects
to use a single local repository after I realized that CVS does much better
what I had previously used RCS for.


Notes on the implementation
---------------------------
The Amiga port implements only the client side of the CVS system. This means
that you can check out projects on remote servers but your local Amiga cannot
be a CVS server itself. This feature was omitted deliberately since I could
not find a safe and useful way to make CVS server mode work on the Amiga.
AmigaOS is not a server operating system and shoehorning the code to make it
work somehow would not have helped. If you need a CVS server, try a dedicated
solution using, for example, 'NetBSD'. The Amiga port can communicate with the
server using the remote shell protocol (rsh), and I have verified that the
process works reasonably well with, for example, the public 'Samba' CVS
repository. If you need a more secure method to communicate with the server
('rsh' is notoriously insecure and many systems no longer support it for
precisely that reason) such as 'Kerberos IV' or 'Secure Shell' (ssh), you'll
have a problem because there are no Amiga ports of these facilities available
yet.

CVS does not have a very sophisticated porting layer. Its file name semantics
all stem from the Unix world and the 'OS/2', 'VMS' and 'Windows NT' ports
merely resort to flipping slashes in file names, if necessary, when it comes to
make a name fit the local system's semantics. I had to find a similar way to
make the semantics work on the Amiga. What I did was to add a translation
service in the Amiga specific code which knows how to translate names like '.'
or '..'. But that's where it ends. Any more sophisticated naming schemes like
'foo/.././bar' may fail to translate properly. But then, those complex
patterns should be pretty rare anyway.

Unlike Heinz Wrobel's excellent 'RCS' port, this CVS port does not preserve
Amiga file protection bits for files checked in. When you check in a project
and check it out again, all file and directory protection bits will default to
'rwed', losing the 'archived', 'pure' and 'script' bits.

The Amiga port will expand wild card patterns for file and directory names
specified as command line parameters, such as "#?.c". The wild card pattern
syntax is that of AmigaDOS. It is *not* the syntax of the standard regular
expressions other GNU tools will use.

You can access remote CVS repositories by means of a properly configured
TCP/IP stack. This port requires that the stack complies to the AmiTCP V3 API
definition, which all modern Amiga TCP/IP stacks do. It does not work with the
INet-225 TCP/IP stack, though.

When CVS resorts to calling external programs, a working 'PIPE:' device is
required, which is not yet part of the AmigaOS Workbench distribution. Do not
underestimate this. The program will fail or behave erratically without a
working 'PIPE:' device. It is strongly recommended to download a working
'queue-handler', such as from Aminet.

The source code for the Amiga port is included in this distribution. All you
need to know before you can recompile this CVS port is described in the file
'README.AMIGA' which you can find in the 'source' directory.

This is a 'single user' CVS port. There is just one single home directory
(referred to as 'CVSHOME:') and your login name and ID are assumed to be the
same (set in the 'USER', 'LOGUSER' or 'USERNAME' environment variables).

There is no 'cvsbug' shell script or program included with this port.


Contacting the author
---------------------
If you have any further questions on this port, feel free to contact us:

   Olaf Barthel
   Brabeckstr. 35
   D-30559 Hannover
   Federal Republic of Germany

   [e-mail]

   Jens Langner
   Lannerstrasse 1
   D-01219 Dresdem
   Federal Republic of Germany

   [e-mail]