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Revision history for Perl extension P4.

3.6001  Tue Aug 07 2007

	Rework change 5787 in which support for taint checking of arguments
	passed to P4::Run() was introduced. It turns out Scalar::Util, on
	which this is based isn't distributed with Perl 5.6, so we can't
	rely on it. This change simply disables the taint checking for
	Perl 5.6 (no-one's using it because it only ever worked for Perl 5.8
	users).

3.5943  Fri May 18 2007

	Update P4Perl to build against 2007.2 API. The 2007.2 API has
	a more traditional directory structure and P4Perl needs to
	take that into account. This change also makes Makefile.PL
	check that the version of the API being used is less than
	or equal to the highest API version known when this version
	was written. 
	
	Hopefully this will prevent people from struggling to build
	older (stable) versions of P4Perl against recent APIs only
	supported by the development builds.

3.5941  Fri May 18 2007

	Documentation updates. Thanks to Steve Vance for pointing
	out some of the shortcomings.

3.5869  Wed Mar 21 2007

	Fix memory leaks. Thanks to John LoVerso and Sandy Currier for
	tracking these down and sending me the patch.

3.5868  Wed Mar 21 2007

	Port P4Perl to Perl 5.8.8. This change is spectacularly ugly,
	but then so are the innards of Perl. See the long thread at:
	
	http://www.nntp.perl.org/group/perl.perl5.porters/2006/06/msg114383.html
	
	for details of the problem, and some discussion of solutions. I've
	had to come up with a solution that doesn't involve patching people's
	Perl installations, so my fix is even less easy on the eye but it 
	appears to work, and hopefully hasn't broken things for older
	Perl versions.

3.5787  Wed Dec 06 2006

	Update P4Perl to build against the 2006.2 API, and detect
	(and reject) the passing of tainted data to P4::Run() as
	a security measure.

3.5708  Wed Oct 18 2006

	Add static P4::Identify() method to report the version of 
	P4Perl, and the API used to build it. 

3.5704  Tue Oct 17 2006

	Fix bug introduced in change 5677: the quoting of the const_char
	definition wasn't good on Windows as it doesn't really understand
	single quotes. Switched to using double-quotes.

3.5692  Fri Oct 06 2006

	Add support for $p4->ServerLevel() which returns the server's
	'server2' protocol level. This is not the same as, but is
	closely aligned to, the server version and can be used
	to test for feature availability. If you need explicit Perforce
	version strings, run 'p4 info' in tagged mode and parse the 
	'serverVersion' string.
	
	New feature requested by Robert Cowham.

3.5677  Tue Sept 26 2006

	Rework P4Perl build script to support 2006.1 API. There were
	some sweeping changes in the 2006.1 API which did away with the
	old const_char definition. Unfortunately, since P4Perl has to
	build with older APIs, I can't quite do the same. This change
	tweaks the way that Makefile.PL determines the definition for
	const_char so that (a) it's always 'const char' when a 2006.1
	or later API is used, (b) it uses the platform specific hint
	for older APIs (c) it falls back on 'char' in the absence of a
	hint.
	
	In an ideal world, we'd be able to compute the options based on
	(a) OS, (b) compiler version (c) Perl version and (d) API version,
	but that's tough to get right.
	
	No functional change.

3.5624  Thu Aug 03 2006

	Add hints file for Mac OS X from Tim Bunce (thanks Tim!).

3.5592  Thu Jul 20 2006

	Bug fix: We were erroneously making a Perl scalar mortal (which causes
	its reference count to be decremented when it goes out of scope) when 
	receiving binary data from the server. Decrementing the reference count
	to early meant the scalar was being cleaned up when it was in fact 
	still in use.
	
	This change simply removes the sv_2mortal() call.
	
	Thanks to Mike Hall at National Instruments for finding this one.

3.5564  Fri Jun 30 2006

	Fix memory leaks when dealing with tagged output with array
	members. One of these days I'll get the hang of Perl's pesky
	reference counting mechanism...
	
	These leaks would have been most noticable with 'p4 filelog' (and
	that's where they were reported), but in fact any command that
	returned tagged output with array members would have leaked.

3.5396  Wed Apr 12 2006

	x86_64 porting changes. Use INT2PTR and PTR2INT to handle the
	stashing of the PerlClientApi pointer in a Perl scalar. This is
	necessary because, despite all documentation to the contrary, an
	I32 is not 64-bit capable on all 64-bit machines.
	
	Also, the hints file now looks for x86_64 in the architecture
	name and if it finds it, then const_char='const char' rather
	than the default of 'char'.

3.5313  Tue Feb 07 2006

	- Add new SetApiLevel() method to allow users to lock scripts to a 
	  particular API level. This helps when upgrading to new servers
	  that extend support for tagged output to hitherto unsupported 
	  commands (2005.2 did a lot of that).
	  
	  See the C/C++ API Release Notes for the full details, but by way of
	  example, to lock scripts to the 2005.1 interface use:
	
		$p4->SetApiLevel( 57 );

3.5259  Thu Jan 12 2006

	- Update P4Perl for 2005.2 API changes. The 2005.2 API supplies forms
	  ready-parsed to the client when used in tagged mode. This is fine for
	  P4Perl, except that we were not caching the specdef if no parsing was
	  required and that meant that although forms could be converted to 
	  hashes, the reverse direction was broken. 
	  
	  This change makes sure that we cache the specdef whenever it's 
	  available.

3.5073  Wed Aug 03 2005

	- Yet another P4::SetProg fix. Turns out the last change fixed
	  everything except the build script and it all worked...
	  unless you used the 2005.1 API which has a different format
	  for the Version file. 
	
	  P4::SetProg is a no-op when P4Perl is built with an older API
	  so not identifying the API build properly breaks it thoroughly.
	
	  This change adapts P4Perl's setup script to support both
	  pre-2005.1 and 2005.1 formats, and gives the user the
	  chance to enter the API version manually if it can't be
	  automatically determined.
	
	- Installers also included in this change

3.5067  Wed Jul 27 2005

	- Bug fix: P4::SetProg() interface method was missing so SetProg
	  wasn't working too well! 

3.5038  Mon Jul 04 2005

	- Bug fix: Fix memory leaks in P4Perl reported by Craig Galley. Perl's
	  reference count garbage collection is not much fun to work with,
	  but hopefully this change plugs P4Perl's leaks. There's still a
	  leak that remains, but whether it's in P4Perl's code or just in 
	  Perl I don't know. A loop like this:
	
	    while( 1 ) {
		my $p4 = new P4;
	    }
	
	  will leak like a sieve but I'm pretty sure P4Perl is cleaning up
	  as it should. While it's very difficult to be certain with Perl's
	  memory mode, creating one P4 object and using it multiple times 
	  now appears to be pretty steady.
	  
	- Also fixed use of uninitialized debug variable which could produce
	  debug output you hadn't asked for.

3.5035  Wed Jun 29 2005

	- Bug fix: call ClientApi::SetProg() before every command instead of
	  just once as this value is not retained by the Perforce API.

3.4987	Fri Jun 03 2005

	- Bug fix for tagged mode output from 'p4 diff2'. Diff2 is one of
	  the few (only?) commands to use variables of the form 'var' and
	  'var2' rather than 'var1' and 'var2'. Normally, if there's no
	  numeric suffix to a variable, P4Perl can assume it's looking at
	  the only instance of that variable in the output. In the case of
	  'p4 diff2', that's not true.
	
	  This change enables P4Perl to adapt to this change of circumstances
	  and convert a previously scalar member of the hash result into an
	  array member.

3.4873	Thu Mar 31 2005

	- Bug fix: fix typos in test harness that were causing the tests
	  to fail.

3.4864	Mon Mar 21 2005

	- Bug fix: Introduce workaround for obscure 2000.1/2000.2 protocol
	  bug that I really thought we'd seen the last of. 
	
	- Along the way, a total revamp of the debugging output - required
	  to diagnose the problem.

3.4856	Wed Mar 15 2005

	- Rework P4::Errors() and P4::Warnings() so that they return a list
	  rather than an array. Perl seems to like this more and it's easy
	  to assign the list to an array should you wish to do so.
	
	  Note that this may cause some backwards-compatibility issues.

3.4831	Wed Feb 09 2005

	- Change implementation of P4 class from being a blessed reference
	  to an integer (pointer) to a blessed reference to a hash. The 
	  pointer is now stashed in a member of the hash. This makes it easier
	  for those that want to to subclass the P4 class and bolt on their own 
	  functionality. No functional change.

3.4804	Thu Jan 20 2005

	- Add support for P4::SetMaxResults() and P4::SetMaxScanRows() which
	  specify the desired limits for an instance of the P4 class. Note
	  that the limits remain in force until disabled by setting them to
	  zero.

3.4754	Tue Jan 11 2005

	- Add support for passing multiple items of input to Perforce commands
	  that need them. The prime example is 'p4 password' which prompts the
	  user three times for password input (old password, new password and
	  new password again). 
	
	- Also add a P4::Password( $old, $new ) method to make it nice and 
	  easy to use.

3.4698 Wed Dec 22 2004

	- Bug fix. Correct client initialization so that it no longer causes
	  problems if the connection to the server fails for some reason.
	
	- Also corrected the number of tests in the test harness.

3.4676 Mon Dec 06 2004

	- Enable P4Perl to work against a server in unicode mode. This change
	  adds two new methods to the P4 class: SetCharset() and GetCharset()
	  which have the expected behaviour.
	
	  Thanks to  Raymond Danks <raymond.danks@amd.com>.

	- Also cleaned up the test harness a little

3.4667 Thu Dec 02 2004

	- New ParseSpec() and FormatSpec() methods allow you to convert
	  specs between hash and string representations easily. Shortcut
	  methods Parse* and Format* are also defined. (i.e. FormatClient()
	  and ParseLabel() etc.)

	- New methods IsTagged() and IsParseForms() tell you if your client
	  is in tagged/form parsing mode respectively. If you care.

	- P4::Tag() is deprecated in favour of P4::Tagged(). P4::Tag() exists
	  for backwards compatibility

3.4608 Mon Oct 25 2004

	- Bug fix: The SetInput() method was omitted in the big rewrite
	  so quite a lot was broken in builds 3.4579 and later. This
	  change fixes that omission, and adds support for 'p4 login'
	  too (that was how I discovered that SetInput() was missing).

3.4585 Mon Oct 18 2004

	- Make P4Perl v3.x backwardly compatible with older versions of
	  the Perforce API.

3.4582 Mon Oct 18 2004

	- Port previous change to NT. As usual, it's never simple. We
	  can't use fprintf( stderr, ... ) because of Perl's stupid
	  macro's. Hence a lot of fprintf()'s got changed to printf()'s.

	- A couple of other minor changes and bugfixes.

3.4579 Fri Oct 15 2004

	- Total rewrite. There's no need for P4::Client anymore, P4.pm is
	  now completely standalone. Of course that means that to build
	  P4.pm, you need to go through the same procedure you used to use
	  for P4-Client. C'est-la-vie. Internally, things are much cleaner
	  and now P4Perl shares the same architecture as P4Ruby so porting
	  new features and bug fixes between them should be much easier.

	- Note that in the course of this change, the clunky DoPerlDiffs() 
	  and DoP4Diffs() methods have been pruned. If you're using 
	  DoPerlDiffs(), and you want to continue to do so, you'll need to
	  either ) continue using a 1.x build.

	- Also note that errors and warnings now go to separate arrays
	  by default (so you can take note of errors, but ignore warnings
	  in your scripts). Users wanting the old behaviour must now
	  call P4::MergeErrors( 1 ). 

	- So why no version '2'? Simple really, P4::Client was already at
	  version 2, and I didn't want to confuse things by having people
	  think that P4::Client might be more recent/or on a par with P4.
	  Hence the jump straight to v3.
	
1.4320 Wed Jun 09 2004

	- Bug fix. Fix the test script so that it handles both tagged and
	  non-tagged output for "p4 info". Tagged support for "p4 info" was
	  added in 2003.2. Thanks to Jeremy Bopp.

1.3550 Wed Aug 06 2003

	- Add support for OutputBinary() to P4Perl classes. This allow
	  "p4 print" to work with binary files, and text files on clients
	  with non-native line endings.

	- Re-add __END__ tag accidentally deleted in previous change

1.3537 Tue Aug 05 2003

	- Documentation change. Added docs for P4::SubmitSpec and
	  P4::SetInput(). No functional change.

1.2587 Fri Jan 10 2003
	- Documentation change. Added docs for P4::Error and P4::ErrorCount.
	  No functional change

1.2003 Wed Aug 07 2002
	- MakeMaker tweaks. No functional change.

1.1733 Tue Apr 30 2002
	- Documentation update and GA release.

0.982 Tue Oct 23 2001
	- Fixed test.pl which was choking on test 6 due to ParseForms()
	  not having been called.

	- Fixed return scheme so that an empty list rather than undef
	  is returned in array context when there are no results.

0.960 Fri Oct 19 2001
	- Added sample code in example.pl

	- Changed SetXXX/GetXXX shortcuts to FetchXXX and SaveXXX since
	  GetClient()/SetClient() were already in use - damn!

	- Changed return scheme so that in scalar context Run() returns
	  an array reference if there is more than one result. Better
	  than a flat string which you then have to parse.

	- Added PPD file contributed by George Ibbott 
	  <gibbott@bakerstreettech.com>

0.931 Mon Oct 8 2001
	- Enhanced interface with some shortcuts for common functions
	  and made it easy to use the form parsing capabilities of 
	  P4::Client v 1.931.

0.10  Mon Oct  1 2001
	- Initial version. 
# Change User Description Committed
#41 6001 Tony Smith Rework change 5787 in which support for taint checking of arguments
passed to P4::Run() was introduced. It turns out Scalar::Util, on
which this is based isn't distributed with Perl 5.6, so we can't
rely on it. This change simply disables the taint checking for
Perl 5.6 (no-one's using it because it only ever worked for Perl 5.8
users).
#40 5943 Tony Smith Update P4Perl to build against 2007.2 API.
The 2007.2 API has
a more traditional directory structure and P4Perl needs to
take that into account. This change also makes Makefile.PL
check that the version of the API being used is less than
or equal to the highest API version known when this version
was written.

Hopefully this will prevent people from struggling to build
older (stable) versions of P4Perl against recent APIs only
supported by the development builds.
#39 5941 Tony Smith Documentation updates.
Thanks to Steve Vance for pointing
out some of the shortcomings.
#38 5869 Tony Smith Fix memory leaks.
Thanks to John LoVerso and Sandy Currier for
tracking these down and sending me the patch.
#37 5868 Tony Smith Port P4Perl to Perl 5.8.8.
This change is spectacularly ugly,
but then so are the innards of Perl. See the long thread at:

http://www.nntp.perl.org/group/perl.perl5.porters/2006/06/msg114383.html

for details of the problem, and some discussion of solutions. I've
had to come up with a solution that doesn't involve patching people's
Perl installations, so my fix is even less easy on the eye but it
appears to work, and hopefully hasn't broken things for older
Perl versions.
#36 5787 Tony Smith Update P4Perl to build against the 2006.2 API, and detect
(and reject) the passing of tainted data to P4::Run() as
a security measure.
#35 5708 Tony Smith Add static P4::Identify() method to report the version of
P4Perl, and the API used to build it.
#34 5704 Tony Smith Fix bug introduced in change 5677: the quoting of the const_char
definition wasn't good on Windows as it doesn't really understand
single quotes. Switched to using double-quotes.
#33 5692 Tony Smith Add support for $p4->ServerLevel() which returns the server's
'server2' protocol level. This is not the same as, but is
closely aligned to, the server version and can be used
to test for feature availability. If you need explicit Perforce
version strings, run 'p4 info' in tagged mode and parse the
'serverVersion' string.

New feature requested by Robert Cowham.
#32 5677 Tony Smith Rework P4Perl build script to support 2006.1 API.
There were
some sweeping changes in the 2006.1 API which did away with the
old const_char definition. Unfortunately, since P4Perl has to
build with older APIs, I can't quite do the same. This change
tweaks the way that Makefile.PL determines the definition for
const_char so that (a) it's always 'const char' when a 2006.1
or later API is used, (b) it uses the platform specific hint
for older APIs (c) it falls back on 'char' in the absence of a
hint.

In an ideal world, we'd be able to compute the options based on
(a) OS, (b) compiler version (c) Perl version and (d) API version,
but that's tough to get right.

No functional change.
#31 5624 Tony Smith Add hints file for Mac OS X from Tim Bunce (thanks Tim!).
#30 5592 Tony Smith Bug fix: We were erroneously making a Perl scalar mortal (which causes
its reference count to be decremented when it goes out of scope) when
receiving binary data from the server. Decrementing the reference count
to early meant the scalar was being cleaned up when it was in fact
still in use.

This change simply removes the sv_2mortal() call.

Thanks to Mike Hall at National Instruments for finding this one.
#29 5564 Tony Smith Fix memory leaks when dealing with tagged output with array
members. One of these days I'll get the hang of Perl's pesky
reference counting mechanism...

These leaks would have been most noticable with 'p4 filelog' (and
that's where they were reported), but in fact any command that
returned tagged output with array members would have leaked.
#28 5396 Tony Smith x86_64 porting changes.
Use INT2PTR and PTR2INT to handle the
stashing of the PerlClientApi pointer in a Perl scalar. This is
necessary because, despite all documentation to the contrary, an
I32 is not 64-bit capable on all 64-bit machines.

Also, the hints file now looks for x86_64 in the architecture
name and if it finds it, then const_char='const char' rather
than the default of 'char'.
#27 5313 Tony Smith Add new SetApiLevel() method to allow users to lock scripts to a
particular API level. This helps when upgrading to new servers
that extend support for tagged output to hitherto unsupported
commands (2005.2 did a lot of that).

See the C/C++ API Release Notes for the full details, but by way of
example, to lock scripts to the 2005.1 interface use:

    $p4->SetApiLevel( 57 );
#26 5259 Tony Smith Update P4Perl for 2005.2 API changes.
The 2005.2 API supplies forms
ready-parsed to the client when used in tagged mode. This is fine for
P4Perl, except that we were not caching the specdef if no parsing was
required and that meant that although forms could be converted to
hashes, the reverse direction was broken.

This change makes sure that we cache the specdef whenever it's
available.
#25 5073 Tony Smith Yet another P4::SetProg fix.
Turns out the last change fixed
everything except the build script and it all worked...
unless you used the 2005.1 API which has a different format
for the Version file.

P4::SetProg is a no-op when P4Perl is built with an older API
so not identifying the API build properly breaks it thoroughly.

This change adapts P4Perl's setup script to support both
pre-2005.1 and 2005.1 formats, and gives the user the
chance to enter the API version manually if it can't be
automatically determined.

Installers also included in this change
#24 5067 Tony Smith Bug fix: P4::SetProg() interface method was missing so SetProg
wasn't working too well!
#23 5038 Tony Smith Bug fix: Fix memory leaks in P4Perl reported by Craig Galley.
Perl's
reference count garbage collection is not much fun to work with,
but hopefully this change plugs P4Perl's leaks. There's still a
leak that remains, but whether it's in P4Perl's code or just in
Perl I don't know. A loop like this:

    while( 1 ) {
    my $p4 = new P4;
    }

will leak like a sieve but I'm pretty sure P4Perl is cleaning up
as it should. While it's very difficult to be certain with Perl's
memory mode, creating one P4 object and using it multiple times
now appears to be pretty steady.

Also fixed use of uninitialized debug variable which could produce
debug output you hadn't asked for.
#22 5035 Tony Smith Bug fix: call ClientApi::SetProg() before every command instead of
just once as this value is not retained by the Perforce API.
#21 4873 Tony Smith Bug fix: fix typos in test harness that were causing the tests
to fail.
#20 4864 Tony Smith Bug fix: Introduce workaround for obscure 2000.1/2000.2 protocol
bug that I really thought we'd seen the last of.

Along the way, a total revamp of the debugging output - required
to diagnose the problem.
#19 4856 Tony Smith Rework P4::Errors() and P4::Warnings() so that they return a list
rather than an array. Perl seems to like this more and it's easy
to assign the list to an array should you wish to do so.

Note that this may cause some backwards-compatibility issues.
#18 4831 Tony Smith Change implementation of P4 class from being a blessed reference
to an integer (pointer) to a blessed reference to a hash. The
pointer is now stashed in a member of the hash. This makes it easier
for those that want to to subclass the P4 class and bolt on their own
functionality. No functional change.
#17 4804 Tony Smith Add support for P4::SetMaxResults() and P4::SetMaxScanRows() which
specify the desired limits for an instance of the P4 class. Note
that the limits remain in force until disabled by setting them to
zero.
#16 4754 Tony Smith Add support for passing multiple items of input to Perforce commands
that need them. The prime example is 'p4 password' which prompts the
user three times for password input (old password, new password and
new password again).

Also add a P4::Password( $old, $new ) method to make it nice and
easy to use.
#15 4698 Tony Smith Bug fix.
Correct client initialization so that it no longer causes
problems if the connection to the server fails for some reason.

Also corrected the number of tests in the test harness.
#14 4676 Tony Smith Enable P4Perl to work against a server in unicode mode.
This change
adds two new methods to the P4 class: SetCharset() and GetCharset()
which have the expected behaviour.

Thanks to  Raymond Danks <raymond.danks@amd.com>.

Also cleaned up the test harness a little.
#13 4667 Tony Smith Caught by the old "hadn't saved my changes" problem, so the
Changes file in the last submission was incomplete. Bumping
the version number to retry...
#12 4666 Tony Smith New ParseSpec() and FormatSpec() methods allow you to convert
specs between hash and string representations easily. Shortcut
methods Parse* and Format* are also defined. (i.e. FormatClient()
and ParseLabel() etc.)

New methods IsTagged() and IsParseForms() tell you if your client
is in tagged/form parsing mode respectively. If you care.

P4::Tag() is deprecated in favour of P4::Tagged(). P4::Tag() exists
for backwards compatibility
#11 4608 Tony Smith Bug fix: The SetInput() method was omitted in the big rewrite
so quite a lot was broken in builds 3.4579 and later. This
change fixes that omission, and adds support for 'p4 login'
too (that was how I discovered that SetInput() was missing).
#10 4586 Tony Smith Update P4Perl tarball with most recent change.
No need for a new
installer as there's no functional change.
#9 4582 Tony Smith Port new P4Perl architecture to Windows.
Fixes a few porting issues and a
couple of minor errors in the previous change.
#8 4579 Tony Smith Rewrite P4Perl to be more like P4Ruby.
This change does away
with the old P4/P4::Client split and pulls all the functionality
of P4::Client into P4. Hence P4::Client is now deprecated.

There are a few gotcha's - see the Changes file, and documentation
for the details, but in general it's backwards compatible.

As part of this change, I'm also releasing the previous current
 versions of P4 and P4::Client as released versions - for posterity.
P4 now gets a v3.x version number so the old versions will stand out
clearly.

Hopefully it's all working - works fine for me - but people should
consider this a beta build, for now at least.
#7 4320 Tony Smith Bug fix.
Fix the test script so that it handles both tagged and
non-tagged output for "p4 info". Tagged support for "p4 info" was
added in 2003.2. Thanks to Jeremy Bopp.
#6 3550 Tony Smith Add OutputBinary() support to P4Perl.
This allows "p4 print" to
work with clients that do not use "local" line endings amongst
other things.
#5 3537 Tony Smith Documentation update.
Added docs for P4::SubmitSpec() and
P4::SetInput() which were missing from previous releases
#4 2587 Tony Smith Add documentation for P4::Errors() and P4::ErrorCount() which
should have been there in the first place
#3 2003 Tony Smith MakeMaker tweaks to cheer up the CPAN folks.
Just guessing with
the PPD file, but it's better than nothing (I'm told).
#2 1733 Tony Smith Documentation update for P4 Perl module.
#1 1011 Tony Smith Moved Perl API stuff one level down to make way for upcoming
Ruby interface.
//guest/tony_smith/perforce/API/P4/Changes
#4 982 Tony Smith A couple of minor fixes.
test.pl was choking on test 6 as
ParseForms had not been called, and Run() now correctly
returns an empty list in array context rather than returning
undef which was confusing.
#3 960 Tony Smith Misc changes.
Added an example.pl file with sample code. Also
Added the PPD file to the manifest (duh!). P4::Run() now returns
an array reference instead of a formatted string when used in
scalar context where more than one result is returned.

Also renamed the shortcut GetXXX and SetXXX methods to be
FetchXXX and SaveXXX because GetClient() and SetClient() we
already defined by P4::Client.
#2 932 Tony Smith Update the Changes file with the released version number,
and add a README file to the package. Not much there yet.
#1 922 Tony Smith First crack at a much simpler perl interface.
Just wraps
up the P4::Client and P4::UI classes in an easier to use
interface returning the output to the caller in Array or
Scalar context as they request it.