# NAME

VCS::SCCS - OO Interface to SCCS files

# SYNOPSIS

    use VCS::SCCS;

    my $sccs = VCS::SCCS->new ("SCCS/s.file.pl");   # Read and parse

    # Meta info
    my $fn = $sccs->file ();            # file.pl
    my $cs = $sccs->checksum ();        # 52534
    my @us = $sccs->users ();           # qw( merijn user )
    my $fl = $sccs->flags ();           # { q => "Test applic", v => undef }
    my $cm = $sccs->comment ();         # ""
    my $cr = $sccs->current ();         # 70
    my @cr = $sccs->current ();         # ( 70, "5.39", 5, 39 )

    # Delta related
    my $vs = $sccs->version ();         # "5.39"
    my $vs = $sccs->version (69);       # "5.38"
    my $rv = $sccs->revision ();        # 70
    my $rv = $sccs->revision ("5.37");  # 68
    my $rm = $sccs->revision_map ();    # [ [ 1, "4.1" ], ... [ 70, "5.39" ]]
    my $dd = $sccs->delta (17);         # none, revision or version as arg

    # Content related
    my $body_70 = $sccs->body ();       # file.pl @70 incl NL's
    my @body_70 = $sccs->body ();       # file.pl @70 list of chomped lines
    my @body_69 = $sccs->body (69);     # same for file.pl at revision 69
    my @body_69 = $sccs->body ("5.38"); # same

    $sccs->set_translate ("SCCS");
    print $sccs->translate ($rev, $line);

    -- NYI --
    my $diff = $sccs->diff (67);        # unified diff between rev 67 and 70
    my $diff = $sccs->diff (63, "5.37");# unified diff between rev 63 and 68

# DESCRIPTION

SCCS was the dominant version control system until the release of the
Revision Control System. Today, SCCS is generally considered obsolete.
However, its file format is still used internally by a few other revision
control programs, including BitKeeper and TeamWare. Sablime\[1\] also allows
the use of SCCS files. The SCCS file format uses a storage technique called
interleaved deltas (or the weave). This storage technique is now considered
by many revision control system developers as key to some advanced merging
techniques, such as the "Precise Codeville" ("pcdv") merge.

This interface aims at the possibility to read those files, without the
need of the sccs utility set, and open up to the possibility of scripts
that use it to convert to more modern VCSs like git, Mercurial, CVS, or
subversion.

# FUNCTIONS

## Meta function

- new (&lt;file>)

    The constructor only accepts a single argument: the SCCS file. this will
    typically be something like `SCCS/s.file.c`.

    If anything in that file makes `new ()` believe that it is not a SCCS
    file, it will return undef. In this stage, there is no way yet to tell
    why `new ()` failed.

- file

    Returns the name of the parsed file. Useful if you have more than a
    single $sccs object.

- checksum

    Returns the checksum that was stored in the file. This module does not
    check if it is valid, nor does it have functionality to calculate a new
    checksum.

- users

    Returns the list of users that was recorded in this file as authorized
    to make deltas/changes.

- flags

    Returns a hash of the flags set for this file (if set at all). VCS::SCCS
    does not do anything with these flags. They are here for the end-user only.

    Note that not all flags are supported by all versions of `admin`, like
    `x` is supported on HP-UX, but not in CSSC.

    - t &lt;type of program>

        File has a user defined value for the %Y% keyword.

    - v \[&lt;program name>\]

        File was flagged to prompt for MR (using &lt;program name> for validation).

    - i &lt;keyword string>

        File was flagged to require id keywords.

    - b

        File was allowed to pass -b to get to create branch deltas.

    - m &lt;module name>

        File has a user defined value for the %M% keyword.

    - f &lt;floor>

        File was given a floor: the lowest release, a number from 1 to 9998, which
        may be get for editing.

    - c &lt;ceiling>

        File was given a ceiling: a number less than or equal to 9999, which can
        be retrieved by a get command.

    - d &lt;default sid>

        File was given a default delta number SID.

    - n

        File created null deltas for skipped major versions.

    - j

        File was flagged to allow concurrent edits on the same SID.

    - l &lt;lock releases>

        File was given a list of releases to which deltas can no longer be made.

    - q &lt;user defined text>

        File has a user defined value for the %Q% keyword.

    - s &lt;line count>

        Defines the number of lines scanned for keyword expansion. Past that
        line, no keyword expansion takes place. Not implemented in all version.

        This flag is a SUN extension that does not exist in historic SCCS
        implementations and is completely ignored by `VCS::SCCS`.

    - x (HP-UX, SCO)

        File was flagged to set execution bit on get. This is the implementation
        that VCS::SCCS knows about.

    - x SCHILY|0 (other)

        Enable SCCS extensions that are not implemented in classical SCCS
        variants. If the `x` flag is enabled, the keywords %D%, %E%, %G%
        and %H% are expanded even though not explicitly enabled by the `y`
        flag.

        This flag is a SCHILY extension that does not exist in historic SCCS
        implementations.

    - y &lt;val> ...

        The list of SCCS keywords to be expanded. If the `y` flag is missing,
        all keywords are expanded. If the flag is present but the list is empty,
        no keyword is expanded and no "No id keywords" message is generated. The
        value `*` controls the expansion of the %sccs.include.filename% keyword.

        This flag is a SUN/SCHILY extension that does not exist in historic SCCS
        implementations.

        This flag is currently ignored in `VCS::SCCS`.

    - z &lt;reserved for use in interfaces>

        Used in Sun's NSE system.

- comment

    The comment that was added when the file was created.

- current

    In scalar context returns the current revision number. That is the
    number of the file that would be restored by get with no arguments.

    In list context, it returns the current revision, version and parts
    of the version, something like `(70, "5.39", 5, 39, undef, undef)`.
    The last 4 numbers are the equivalent of the keywords %R%, %L%, %B%,
    and %S% for that release.

- set\_translate (&lt;type>)

    By default VCS::SCCS will not translate the SCCS keywords (like `%W%`,
    see `translate ()` for the full list). With `set_translate ()`, you
    can select a translation type: `SCCS` is currently the only supported
    type, `CVS` and `RCS` are planned. Passing a false argument will reset
    translation to none.

    You can also pass a hashref that will do custom translation:

        my %trans = (
          "%W%" => "This is my what id",
          "%E%" => "Yesterday",
          "%U%" => "Noon",
          #...
          };
        $sccs->set_translate (\%tran);

    any missing keywords will not be translated.

## Delta functions

- delta
- delta (&lt;revision>)
- delta (&lt;version>)

    If called without argument, it returns the delta of the last revision
    as a hashref.

    If called with a revision argument, it returns you the delta of that
    revision. If there is no such revision, returns undef.

    If called with a version argument, it returns you the delta of that
    version. If there is no such version, returns undef.

    The elements of the hash returned are:

    - lines\_ins

        The number of lines inserted in this delta

    - lines\_del

        The number of lines deleted in this delta

    - lines\_unc

        The number of lines unchanged in this delta

    - type

        The type of this delta. Usually this will be a `D`, but it could
        also be a `R`, which has not (yet) been tested.

    - version

        The version (SID) of this delta

    - release

        The release number of this delta

    - level

        The level number of this delta

    - branch

        The branch number of this delta. Can be undef

    - sequence

        The sequence number of this delta. Can be undef

    - date

        The date this delta was submitted in YY/MM/DD format

    - time

        The time this delta was submitted in HH:MM:SS format

    - stamp

        The `date` and `time` elements converted to a unix time stamp

    - committer

        The logname of the user that committed this delta

    - mr

        The MR numbers of this delta, separated by ", "

    - comment

        The comment as entered with this delta

- version
- version (&lt;revision>)

    If called without argument, it returns the last version, just as
    the second return value of `current ()` in list context.

    If called with a revision argument, it returns you the version that
    matches that revision. It returns undef if no matching version is
    found.

- revision
- revision (&lt;version>)

    If called without argument, it returns the last revision, just as
    `current ()` returns in scalar context.

    If called with a version argument, it returns you the revision that
    matches that version. It returns undef if no matching revision is
    found.

- revision\_map

    Returns an anonymous list of `revision` - `version` pairs (in
    anonymous lists).

## Content function

- body
- body (&lt;revision>)
- body (&lt;version>)

    In scalar context returns the full body for the given revision.
    If no revision is passed, the current (most recent) revision is
    used. If a version is passed, the matching revision will be used.
    If the is no matching version or revision, `body ()` returns
    `undef`.

    In list context, `body ()` returns the list of chomped lines for
    the given revision.

    `body ()` will use the translation set by `set_translate ()`.

- diff

    NYI

- translate (&lt;revision>, &lt;text>)

    Translate the SCCS keywords in the text passed using the plan set
    with `set_translate ()`.

    The SCCS keywords are

    - %M%

        Module name: either the value of the m flag in the file (see `flags`),
        or if absent, the name of the SCCS file with the leading s. removed.

    - %I%

        SCCS identification (SID) (%R%.%L%.%B%.%S%) of the retrieved text.

    - %R%

        Release.

    - %L%

        Level.

    - %B%

        Branch.

    - %S%

        Sequence.

    - %D%

        Current date (YY/MM/DD).

    - %H%

        Current date (MM/DD/YY).

    - %T%

        Current time (HH:MM:SS).

    - %E%

        Date newest applied delta was created (YY/MM/DD).

    - %G%

        Date newest applied delta was created (MM/DD/YY).

    - %U%

        Time newest applied delta was created (HH:MM:SS).

    - %Y%

        Module type: value of the t flag in the SCCS file (see `flags`).

    - %F%

        SCCS file name.

    - %P%

        Fully qualified SCCS file name.

    - %Q%

        The value of the q flag in the file (see `flags`).

    - %C%

        Current line number.  This keyword is intended for identifying messages
        output by the program such as --this should not have happened-- type
        errors.  It is not intended to be used on every line to provide sequence
        numbers.

    - %Z%

        The 4-character string @(#) @(#) recognizable by what (see what(1)).

    - %W%

        A shorthand notation for constructing what(1) strings for HP-UX system
        program files.  %W%=%Z%%M%horizontal-tab%I%

    - %A%

        Another shorthand notation for constructing what(1) strings for
        non-HP-UX system program files.  %A% = %Z%%Y% %M% %I%%Z%

    For now, %D%, %H%, %T%, %G%, %F%, %P%, and %C% are not translated.
    I see no use for %D%, %H%, or %T%. People that use %G% have enough
    problems already, so they should be able to cope, %F% and %P% lose
    their meaning after conversion and %C% might be done later.

    If you convert from SCCS to git, it might be advisable to not do
    any translation at all, and leave the keywords in, just the way
    they are, and create a checkout hook.

# SPECIFICATION

SCCS file format is reasonable well documented. I have included a
manual page for sccsfile for HP-UX in doc/

# EXAMPLES

See the files in examples/ for my attempts to start converters to
other VCSs

# BUGS AND LIMITATIONS

As this module is created as a base for conversion to more useful
and robust VCSs, it is a read-only interface to the SCCS files.

Translation is incomplete and might be questionable, but at least
there is a workaround.

# TODO

    * improve documentation
    * implement diff ()
    * more tests
    * autodetect the available VCS candidates for sccs2***
    * sccs2git documentation and installation
    * sccs2rcs
    * sccs2cvs
    * sccs2hg
    * sccs2svn
    * errors and warnings
    * provide hooks to VCS::

# DIAGNOSTICS

First errors, than diagnostics ...

# SEE ALSO

- SCCS

    source code at http://sccs.sourceforge.net/

    manual pages at http://sccs.sourceforge.net/man/index.html

    http://en.wikipedia.org/wiki/Source\_Code\_Control\_System

- CSSC

    https://sourceforge.net/projects/cssc
    A GNU project that aims to be a drop-in replacement for SCCS. It is
    written in c++ and therefor disqualifies to be used at any older OS
    that does support SCCS but has no C++ compiler. And even if you have
    one, there is a good chance it won't build or does not bass the basic
    tests. I did not get it to work.

- VCS

    http://search.cpan.org/dist/VCS

- GIT

    http://www.kernel.org/pub/software/scm/git/docs/

# AUTHOR

H.Merijn Brand <h.m.brand@xs4all.nl>

# LICENSE AND COPYRIGHT

Copyright (C) 2007-2020 H.Merijn Brand

This library is free software; you can redistribute it and/or modify
it under the same terms as Perl itself.
