forked from openkylin/libfreezethaw-perl
891 lines
25 KiB
Perl
Executable File
891 lines
25 KiB
Perl
Executable File
=head1 NAME
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FreezeThaw - converting Perl structures to strings and back.
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=head1 SYNOPSIS
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use FreezeThaw qw(freeze thaw cmpStr safeFreeze cmpStrHard);
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$string = freeze $data1, $data2, $data3;
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...
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($olddata1, $olddata2, $olddata3) = thaw $string;
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if (cmpStr($olddata2,$data2) == 0) {print "OK!"}
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=head1 DESCRIPTION
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Converts data to/from stringified form, appropriate for
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saving-to/reading-from permanent storage.
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Deals with objects, circular lists, repeated appearence of the same
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refence. Does not deal with overloaded I<stringify> operator yet.
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=head1 EXPORT
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=over 12
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=item Default
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None.
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=item Exportable
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C<freeze thaw cmpStr cmpStrHard safeFreeze>.
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=back
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=head1 User API
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=over 12
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=item C<cmpStr>
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analogue of C<cmp> for data. Takes two arguments and compares them as
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separate entities.
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=item C<cmpStrHard>
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analogue of C<cmp> for data. Takes two arguments and compares them
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considered as a group.
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=item C<freeze>
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returns a string that encupsulates its arguments (considered as a
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group). C<thaw>ing this string leads to a fatal error if arguments to
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C<freeze> contained references to C<GLOB>s and C<CODE>s.
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=item C<safeFreeze>
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returns a string that encupsulates its arguments (considered as a
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group). The result is C<thaw>able in the same process. C<thaw>ing the
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result in a different process should result in a fatal error if
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arguments to C<safeFreeze> contained references to C<GLOB>s and
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C<CODE>s.
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=item C<thaw>
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takes one string argument and returns an array. The elements of the
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array are "equivalent" to arguments of the C<freeze> command that
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created the string. Can result in a fatal error (see above).
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=back
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=head1 Developer API
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C<FreezeThaw> C<freeze>s and C<thaw>s data blessed in some package by
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calling methods C<Freeze> and C<Thaw> in the package. The fallback
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methods are provided by the C<FreezeThaw> itself. The fallback
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C<Freeze> freezes the "content" of blessed object (from Perl point of
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view). The fallback C<Thaw> blesses the C<thaw>ed data back into the package.
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So the package needs to define its own methods only if the fallback
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methods will fail (for example, for a lot of data the "content" of an
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object is an address of some B<C> data). The methods are called like
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$newcooky = $obj->Freeze($cooky);
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$obj = Package->Thaw($content,$cooky);
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To save and restore the data the following method are applicable:
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$cooky->FreezeScalar($data,$ignorePackage,$noduplicate);
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during Freeze()ing, and
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$data = $cooky->ThawScalar;
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Two optional arguments $ignorePackage and $noduplicate regulate
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whether the freezing should not call the methods even if $data is a
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reference to a blessed object, and whether the data should not be
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marked as seen already even if it was seen before. The default methods
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sub UNIVERSAL::Freeze {
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my ($obj, $cooky) = (shift, shift);
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$cooky->FreezeScalar($obj,1,1);
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}
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sub UNIVERSAL::Thaw {
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my ($package, $cooky) = (shift, shift);
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my $obj = $cooky->ThawScalar;
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bless $obj, $package;
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}
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call the C<FreezeScalar> method of the $cooky since the freezing
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engine will see the data the second time during this call. Indeed, it
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is the freezing engine who calls UNIVERSAL::Freeze(), and it calls it
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because it needs to freeze $obj. The above call to
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$cooky->FreezeScalar() handles the same data back to engine, but
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because flags are different, the code does not cycle.
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Freezing and thawing $cooky also allows the following additional methods:
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$cooky->isSafe;
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to find out whether the current freeze was initiated by C<freeze> or
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C<safeFreeze> command. Analogous method for thaw $cooky returns
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whether the current thaw operation is considered safe (i.e., either
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does not contain cached elsewhere data, or comes from the same
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application). You can use
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$cooky->makeSafe;
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to prohibit cached data for the duration of the rest of freezing or
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thawing of current object.
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Two methods
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$value = $cooky->repeatedOK;
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$cooky->noRepeated; # Now repeated are prohibited
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allow to find out/change the current setting for allowing repeated
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references.
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If you want to flush the cache of saved objects you can use
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FreezeThaw->flushCache;
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this can invalidate some frozen string, so that thawing them will
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result in fatal error.
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=head2 Instantiating
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Sometimes, when an object from a package is recreated in presense of
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repeated references, it is not safe to recreate the internal structure
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of an object in one step. In such a situation recreation of an object
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is carried out in two steps: in the first the object is C<allocate>d,
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in the second it is C<instantiate>d.
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The restriction is that during the I<allocation> step you cannot use any
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reference to any Perl object that can be referenced from any other
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place. This restriction is applied since that object may not exist yet.
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Correspondingly, during I<instantiation> step the previosly I<allocated>
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object should be C<filled>, i.e., it can be changed in any way such
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that the references to this object remain valid.
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The methods are called like this:
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$pre_object_ref = Package->Allocate($pre_pre_object_ref);
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# Returns reference
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Package->Instantiate($pre_object_ref,$cooky);
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# Converts into reference to blessed object
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The reverse operations are
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$object_ref->FreezeEmpty($cooky);
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$object_ref->FreezeInstance($cooky);
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during these calls object can C<freezeScalar> some information (in a
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usual way) that will be used during C<Allocate> and C<Instantiate>
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calls (via C<thawScalar>). Note that the return value of
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C<FreezeEmpty> is cached during the phase of creation of uninialized
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objects. This B<must> be used like this: the return value is the
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reference to the created object, so it is not destructed until other
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objects are created, thus the frozen values of the different objects
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will not share the same references. Example of bad result:
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$o1->FreezeEmpty($cooky)
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freezes C<{}>, and C<$o2-E<gt>FreezeEmpty($cooky)> makes the same. Now
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nobody guaranties that that these two copies of C<{}> are different,
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unless a reference to the first one is preserved during the call to
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C<$o2-E<gt>FreezeEmpty($cooky)>. If C<$o1-E<gt>FreezeEmpty($cooky)>
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returns the value of C<{}> it uses, it will be preserved by the
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engine.
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The helper function C<FreezeThaw::copyContents> is provided for
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simplification of instantiation. The syntax is
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FreezeThaw::copyContents $to, $from;
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The function copies contents the object $from point to into what the
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object $to points to (including package for blessed references). Both
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arguments should be references.
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The default methods are provided. They do the following:
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=over 12
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=item C<FreezeEmpty>
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Freezes an I<empty> object of underlying type.
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=item C<FreezeInstance>
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Calls C<Freeze>.
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=item C<Allocate>
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Thaws what was frozen by C<FreezeEmpty>.
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=item C<Instantiate>
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Thaws what was frozen by C<FreezeInstance>, uses C<copyContents> to
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transfer this to the $pre_object.
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=back
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=head1 BUGS and LIMITATIONS
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A lot of objects are blessed in some obscure packages by XSUB
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typemaps. It is not clear how to (automatically) prevent the
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C<UNIVERSAL> methods to be called for objects in these packages.
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The objects which can survive freeze()/thaw() cycle must also survive a
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change of a "member" to an equal member. Say, after
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$a = [a => 3];
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$a->{b} = \ $a->{a};
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$a satisfies
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$a->{b} == \ $a->{a}
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This property will be broken by freeze()/thaw(), but it is also broken by
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$a->{a} = delete $a->{a};
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=cut
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require 5.002; # defined ref stuff...
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# Different line noise chars:
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#
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# $567| next 567 chars form a scalar
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#
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# @34| next 34 scalars form an array
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#
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# %34| next 34 scalars form a hash
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#
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# ? next scalar is a safe-stamp at beginning
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#
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# ? next scalar is a stringified data
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#
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# ! repeated array follows (after a scalar denoting array $#),
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# (possibly?) followed by instantiation array. At beginning
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#
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# <45| ordinal of element in repeated array
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#
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# * stringified glob follows
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#
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# & stringified coderef follows
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#
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# \\ stringified defererenced data follows
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#
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# / stringified REx follows
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#
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# > stringified package name follows, then frozen data
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#
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# { stringified package name follows, then allocation data
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#
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# } stringified package name follows, then instantiation data
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#
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# _ frozen form of undef
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package FreezeThaw;
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use Exporter;
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@ISA = qw(Exporter);
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$VERSION = '0.5001';
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@EXPORT_OK = qw(freeze thaw cmpStr cmpStrHard safeFreeze);
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use strict;
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use Carp;
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my $lock = (reverse time) ^ $$ ^ \&freezeString; # To distingush processes
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use vars qw( @multiple
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%seen_packages
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$seen_packages
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%seen_packages
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%count
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%address
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$string
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$unsafe
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$noCache
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$cooky
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$secondpass
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), # Localized in freeze()
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qw( $norepeated ), # Localized in freezeScalar()
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qw( $uninitOK ), # Localized in thawScalar()
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qw( @uninit ), # Localized in thaw()
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qw($safe); # Localized in safeFreeze()
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BEGIN { # allow optimization away
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my $haveIsRex = defined &re::is_regexp;
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my $RexIsREGEXP = ($haveIsRex and # 'REGEXP' eq ref qr/1/); # First-class REX
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$] >= 5.011); # Code like above requires Scalar::Utils::reftype
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eval <<EOE or die;
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sub haveIsRex () {$haveIsRex}
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sub RexIsREGEXP () {$RexIsREGEXP}
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1
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EOE
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}
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my (%saved);
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my %Empty = ( ARRAY => sub {[]}, HASH => sub {{}},
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SCALAR => sub {my $undef; \$undef},
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REF => sub {my $undef; \$undef},
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CODE => 1, # 1 means atomic
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GLOB => 1,
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(RexIsREGEXP
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? (Regexp => sub {my $qr = qr//})
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: (Regexp => 0)),
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);
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# This should better be done via pos() and \G, but apparently \G is not
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# optimized (bug in the REx optimizer???)
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BEGIN {
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my $pointer_size = length pack 'p', 0;
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#my $max_dig0 = 3*$pointer_size; # 8bits take less than 3 decimals
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# Now calculate the exact value:
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#my $max_pointer = sprintf "%.${max_dig0}g", 0x100**$pointer_size;
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my $max_pointer = sprintf "%.0f", 0x100**$pointer_size;
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die "Panic" if $max_pointer =~ /\D/;
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my $max_pointer_l = length $max_pointer;
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warn "Max pointer_l=$max_pointer_l" if $ENV{FREEZE_THAW_WARN};
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eval "sub max_strlen_l () {$max_pointer_l}; 1" or die;
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}
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sub flushCache {$lock ^= rand; undef %saved;}
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sub getref ($) {
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my $ref = ref $_[0];
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return $ref if not $ref or defined $Empty{$ref}; # Optimization _and_ Regexp
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my $str;
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if (defined &overload::StrVal) {
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$str = overload::StrVal($_[0]);
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} else {
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$str = "$_[0]";
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}
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$ref = $1 if $str =~ /=(\w+)/;
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$ref;
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}
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sub freezeString {$string .= "\$" . length($_[0]) . '|' . $_[0]}
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sub freezeNumber {$string .= $_[0] . '|'}
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sub freezeREx {$string .= '/' . length($_[0]) . '|' . $_[0]}
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sub thawString { # Returns list: a string and offset of rest
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substr($string, $_[0], 2+max_strlen_l) =~ /^\$(\d+)\|/
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or confess "Wrong format of frozen string: " . substr($string, $_[0]);
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length($string) - $_[0] > length($1) + 1 + $1
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or confess "Frozen string too short: `" .
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substr($string, $_[0]) . "', expect " . (length($1) + 2 + $1);
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(substr($string, $_[0] + length($1) + 2, $1), $_[0] + length($1) + 2 + $1);
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}
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sub thawNumber { # Returns list: a number and offset of rest
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substr($string, $_[0], 1+max_strlen_l) =~ /^(\d+)\|/
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or confess "Wrong format of frozen string: " . substr($string, $_[0]);
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($1, $_[0] + length($1) + 1);
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}
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sub _2rex ($);
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if (eval 'ref qr/1/') {
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eval 'sub _2rex ($) {my $r = shift; qr/$r/} 1' or die;
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} else {
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eval 'sub _2rex ($) { shift } 1' or die;
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}
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sub thawREx { # Returns list: a REx and offset of rest
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substr($string, $_[0], 2+max_strlen_l) =~ m,^/(\d+)\|,
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or confess "Wrong format of frozen REx: " . substr($string, $_[0]);
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length($string) - $_[0] > length($1) + 1 + $1
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or confess "Frozen string too short: `" .
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substr($string, $_[0]) . "', expect " . (length($1) + 2 + $1);
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(_2rex substr($string, $_[0] + length($1) + 2, $1),
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$_[0] + length($1) + 2 + $1);
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}
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sub freezeArray {
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$string .= '@' . @{$_[0]} . '|';
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for (@{$_[0]}) {
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freezeScalar($_);
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}
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}
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sub thawArray {
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substr($string, $_[0], 2+max_strlen_l) =~ /^[\@%](\d+)\|/ # % To make it possible thaw hashes
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or confess "Wrong format of frozen array: \n$_[0]";
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my $count = $1;
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my $off = $_[0] + 2 + length $count;
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my (@res, $res);
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while ($count and length $string > $off) {
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($res,$off) = thawScalar($off);
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push(@res,$res);
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--$count;
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}
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confess "Wrong length of data in thawing Array: $count left" if $count;
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(\@res, $off);
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}
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sub freezeHash {
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my @arr = sort keys %{$_[0]};
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$string .= '%' . (2*@arr) . '|';
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for (@arr, @{$_[0]}{@arr}) {
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freezeScalar($_);
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}
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}
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sub thawHash {
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my ($arr, $rest) = &thawArray;
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my %hash;
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my $l = @$arr/2;
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foreach (0 .. $l - 1) {
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$hash{$arr->[$_]} = $arr->[$l + $_];
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}
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(\%hash,$rest);
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}
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# Second optional argument: ignore the package
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# Third optional one: do not check for duplicates on outer level
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sub freezeScalar {
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$string .= '_', return unless defined $_[0];
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return &freezeString unless ref $_[0];
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my $ref = ref $_[0];
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my $str;
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if ($_[1] and $ref) { # Similar to getref()
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if (defined &overload::StrVal) {
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$str = overload::StrVal($_[0]);
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} else {
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$str = "$_[0]";
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}
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$ref = $1 if $str =~ /=(\w+)/;
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} else {
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$str = "$_[0]";
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}
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# Die if a) repeated prohibited, b) met, c) not explicitely requested to ingore.
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confess "Repeated reference met when prohibited"
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if $norepeated && !$_[2] && defined $count{$str};
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if ($secondpass and !$_[2]) {
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$string .= "<$address{$str}|", return
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if defined $count{$str} and $count{$str} > 1;
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} elsif (!$_[2]) {
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# $count{$str} is defined if we have seen it on this pass.
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$address{$str} = @multiple, push(@multiple, $_[0])
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if defined $count{$str} and not exists $address{$str};
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# This is for debugging and shortening thrown-away output (also
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# internal data in arrays and hashes is not duplicated).
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$string .= "<$address{$str}|", ++$count{$str}, return
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if defined $count{$str};
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++$count{$str};
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}
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return &freezeArray if $ref eq 'ARRAY';
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return &freezeHash if $ref eq 'HASH';
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return &freezeREx if haveIsRex ? re::is_regexp($_[0])
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: ($ref eq 'Regexp' and not defined ${$_[0]});
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$string .= "*", return &freezeString
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if $ref eq 'GLOB' and !$safe;
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$string .= "&", return &freezeString
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if $ref eq 'CODE' and !$safe;
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$string .= '\\', return &freezeScalar( $ {shift()} )
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if $ref eq 'REF' or $ref eq 'SCALAR';
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if ($noCache and (($ref eq 'CODE') or $ref eq 'GLOB')) {
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confess "CODE and GLOB references prohibited now";
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}
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if ($safe and (($ref eq 'CODE') or $ref eq 'GLOB')) {
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$unsafe = 1;
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$saved{$str} = $_[0] unless defined $saved{$str};
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$string .= "?";
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return &freezeString;
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}
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$string .= '>';
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local $norepeated = $norepeated;
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local $noCache = $noCache;
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freezePackage(ref $_[0]);
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$_[0]->Freeze($cooky);
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}
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sub freezePackage {
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my $packageid = $seen_packages{$_[0]};
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if (defined $packageid) {
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$string .= ')';
|
|
&freezeNumber( $packageid );
|
|
} else {
|
|
$string .= '>';
|
|
&freezeNumber( $seen_packages );
|
|
&freezeScalar( $_[0] );
|
|
$seen_packages{ $_[0] } = $seen_packages++;
|
|
}
|
|
}
|
|
|
|
sub thawPackage { # First argument: offset
|
|
my $key = substr($string,$_[0],1);
|
|
my ($get, $rest, $id);
|
|
($id, $rest) = &thawNumber($_[0] + 1);
|
|
if ($key eq ')') {
|
|
$get = $seen_packages{$id};
|
|
} else {
|
|
($get, $rest) = &thawString($rest);
|
|
$seen_packages{$id} = $get;
|
|
}
|
|
($get, $rest);
|
|
}
|
|
|
|
# First argument: offset; Optional other: index in the @uninit array
|
|
|
|
sub thawScalar {
|
|
my $key = substr($string,$_[0],1);
|
|
if ($key eq "\$") {&thawString}
|
|
elsif ($key eq '@') {&thawArray}
|
|
elsif ($key eq '%') {&thawHash}
|
|
elsif ($key eq '/') {&thawREx}
|
|
elsif ($key eq '\\') {
|
|
my ($out,$rest) = &thawScalar( $_[0]+1 ) ;
|
|
(\$out,$rest);
|
|
}
|
|
elsif ($key eq '_') { (undef, $_[0]+1) }
|
|
elsif ($key eq '&') {confess "Do not know how to thaw CODE"}
|
|
elsif ($key eq '*') {confess "Do not know how to thaw GLOB"}
|
|
elsif ($key eq '?') {
|
|
my ($address,$rest) = &thawScalar( $_[0]+1 ) ;
|
|
confess "The saved data accessed in unprotected thaw" unless $unsafe;
|
|
confess "The saved data disappeared somewhere"
|
|
unless defined $saved{$address};
|
|
($saved{$address},$rest);
|
|
} elsif ($key eq '<') {
|
|
confess "Repeated data prohibited at this moment" unless $uninitOK;
|
|
my ($off,$end) = &thawNumber ($_[0]+1);
|
|
($uninit[$off],$end);
|
|
} elsif ($key eq '>' or $key eq '{' or $key eq '}') {
|
|
my ($package,$rest) = &thawPackage( $_[0]+1 );
|
|
my $cooky = bless \$rest, 'FreezeThaw::TCooky';
|
|
local $uninitOK = $uninitOK;
|
|
local $unsafe = $unsafe;
|
|
if ($key eq '{') {
|
|
my $res = $package->Allocate($cooky);
|
|
($res, $rest);
|
|
} elsif ($key eq '}') {
|
|
warn "Here it is undef!" unless defined $_[1];
|
|
$package->Instantiate($uninit[$_[1]],$cooky);
|
|
(undef, $rest);
|
|
} else {
|
|
($package->Thaw($cooky),$rest);
|
|
}
|
|
} else {
|
|
confess "Do not know how to thaw data with code `$key'";
|
|
}
|
|
}
|
|
|
|
sub freezeEmpty { # Takes a type, freezes ref to empty object
|
|
my $e = $Empty{ref $_[0]};
|
|
if (ref $e) {
|
|
my $cache = &$e;
|
|
freezeScalar $cache;
|
|
$cache;
|
|
} elsif ($e) {
|
|
my $cache = shift;
|
|
freezeScalar($cache,1,1); # Atomic
|
|
$cache;
|
|
} else {
|
|
$string .= "{";
|
|
freezePackage ref $_[0];
|
|
$_[0]->FreezeEmpty($cooky);
|
|
}
|
|
}
|
|
|
|
sub freeze {
|
|
local @multiple;
|
|
local %seen_packages;
|
|
local $seen_packages = 0;
|
|
local %seen_packages;
|
|
# local @seentypes;
|
|
local %count;
|
|
local %address;
|
|
local $string = 'FrT;';
|
|
local $unsafe;
|
|
local $noCache;
|
|
local $cooky = bless \$cooky, 'FreezeThaw::FCooky'; # Just something fake
|
|
local $secondpass;
|
|
freezeScalar(\@_);
|
|
if (@multiple) {
|
|
# Now repeated structures are enumerated with order of *second* time
|
|
# they appear in the what we freeze.
|
|
# What we want is to have them enumerated with respect to the first time
|
|
#### $string = ''; # Start again
|
|
#### @multiple = ();
|
|
#### %address = ();
|
|
#### for (keys %count) {
|
|
#### $count{$_} = undef if $count{$_} <= 1; # As at start
|
|
#### $count{$_} = 0 if $count{$_}; # As at start
|
|
#### }
|
|
#### $seen_packages = 0;
|
|
#### %seen_packages = ();
|
|
#### freezeScalar(\@_);
|
|
# Now repeated structures are enumerated with order of first time
|
|
# they appear in the what we freeze
|
|
#### my $oldstring = substr $string, 4;
|
|
$string = 'FrT;!'; # Start again
|
|
$seen_packages = 0;
|
|
%seen_packages = (); # XXXX We reshuffle parts of the
|
|
# string, so the order of packages may
|
|
# be wrong...
|
|
freezeNumber($#multiple);
|
|
{
|
|
my @cache; # Force different values for different
|
|
# empty objects.
|
|
foreach (@multiple) {
|
|
push @cache, freezeEmpty $_;
|
|
}
|
|
}
|
|
# for (keys %count) {
|
|
# $count{$_} = undef
|
|
# if !(defined $count{$_}) or $count{$_} <= 1; # As at start
|
|
# }
|
|
# $string .= '@' . @multiple . '|';
|
|
$secondpass = 1;
|
|
for (@multiple) {
|
|
freezeScalar($_,0,1,1), next if $Empty{ref $_};
|
|
$string .= "}";
|
|
freezePackage ref $_;
|
|
$_->FreezeInstance($cooky);
|
|
}
|
|
#### $string .= $oldstring;
|
|
freezeScalar(\@_);
|
|
}
|
|
return "FrT;?\$" . length($lock) . "|" . $lock . substr $string, 4
|
|
if $unsafe;
|
|
$string;
|
|
}
|
|
|
|
sub safeFreeze {
|
|
local $safe = 1;
|
|
&freeze;
|
|
}
|
|
|
|
sub copyContents { # Given two references, copies contents of the
|
|
# second one to the first one, provided they have
|
|
# the same basic type. The package is copied too.
|
|
my($first,$second) = @_;
|
|
my $ref = getref $second;
|
|
if ($ref eq 'SCALAR' or $ref eq 'REF') {
|
|
$$first = $$second;
|
|
} elsif ($ref eq 'ARRAY') {
|
|
@$first = @$second;
|
|
} elsif ($ref eq 'HASH') {
|
|
%$first = %$second;
|
|
} elsif (haveIsRex ? re::is_regexp($second)
|
|
: ($ref eq 'Regexp' and not defined $$second)) {
|
|
$first = qr/$second/;
|
|
} else {
|
|
croak "Don't know how to copyContents of type `$ref'";
|
|
}
|
|
if (ref $second ne ref $first) { # Rebless
|
|
# SvAMAGIC() is a property of a reference, not of a referent!
|
|
# Thus we cannot use $first here if $second was overloaded...
|
|
bless $_[0], ref $second;
|
|
}
|
|
$first;
|
|
}
|
|
|
|
sub thaw {
|
|
confess "thaw requires one argument" unless @_ ==1;
|
|
local $string = shift;
|
|
local %seen_packages;
|
|
my $initoff = 0;
|
|
#print STDERR "Thawing `$string'", substr ($string, 0, 4), "\n";
|
|
if (substr($string, 0, 4) ne 'FrT;') {
|
|
warn "Signature not present, continuing anyway" if $^W;
|
|
} else {
|
|
$initoff = 4;
|
|
}
|
|
local $unsafe = $initoff + (substr($string, $initoff, 1) eq "?" ? 1 : 0);
|
|
if ($unsafe != $initoff) {
|
|
my $key;
|
|
($key,$unsafe) = thawScalar($unsafe);
|
|
confess "The lock in frozen data does not match the key"
|
|
unless $key eq $lock;
|
|
}
|
|
local @multiple;
|
|
local $uninitOK = 1; # The methods can change it.
|
|
my $repeated = substr($string,$unsafe,1) eq '!' ? 1 : 0;
|
|
my ($res, $off);
|
|
if ($repeated) {
|
|
($res, $off) = thawNumber($repeated + $unsafe);
|
|
} else {
|
|
($res, $off) = thawScalar($repeated + $unsafe);
|
|
}
|
|
my $cooky = bless \$off, 'FreezeThaw::TCooky';
|
|
if ($repeated) {
|
|
local @uninit;
|
|
my $lst = $res;
|
|
foreach (0..$lst) {
|
|
($res, $off) = thawScalar($off, $_);
|
|
push(@uninit, $res);
|
|
}
|
|
my @init;
|
|
foreach (0..$lst) {
|
|
($res, $off) = thawScalar($off, $_);
|
|
push(@init, $res);
|
|
}
|
|
#($init, $off) = thawScalar($off);
|
|
#print "Instantiating...\n";
|
|
#my $ref;
|
|
for (0..$#uninit) {
|
|
copyContents $uninit[$_], $init[$_] if ref $init[$_];
|
|
}
|
|
($res, $off) = thawScalar($off);
|
|
}
|
|
croak "Extra elements in frozen structure: `" . substr($string,$off) . "'"
|
|
if $off != length $string;
|
|
return @$res;
|
|
}
|
|
|
|
sub cmpStr {
|
|
confess "Compare requires two arguments" unless @_ == 2;
|
|
freeze(shift) cmp freeze(shift);
|
|
}
|
|
|
|
sub cmpStrHard {
|
|
confess "Compare requires two arguments" unless @_ == 2;
|
|
local @multiple;
|
|
# local @seentypes;
|
|
local %count;
|
|
local %address;
|
|
local $string = 'FrT;';
|
|
local $unsafe;
|
|
local $noCache;
|
|
local $cooky = bless \$cooky, 'FreezeThaw::FCooky'; # Just something fake
|
|
freezeScalar($_[0]);
|
|
my %cnt1 = %count;
|
|
freezeScalar($_[1]);
|
|
my %cnt2 = %count;
|
|
%count = ();
|
|
# Now all the caches are filled, delete the entries for guys which
|
|
# are in one argument only.
|
|
my ($elt, $val);
|
|
while (($elt, $val) = each %cnt1) {
|
|
$count{$elt}++ if $cnt2{$elt} > $cnt1{$elt};
|
|
}
|
|
$string = '';
|
|
freezeScalar($_[0]);
|
|
my $str1 = $string;
|
|
$string = '';
|
|
freezeScalar($_[1]);
|
|
$str1 cmp $string;
|
|
}
|
|
|
|
# local $string = freeze(shift,shift);
|
|
# local $uninitOK = 1;
|
|
# #print "$string\n";
|
|
# my $off = 7; # Hardwired offset after @2|
|
|
# if (substr($string,4,1) eq '!') {
|
|
# $off = 5; # Hardwired offset after !
|
|
# my ($uninit, $len);
|
|
# ($len,$off) = thawScalar $off;
|
|
# local @uninit;
|
|
# foreach (0..$len) {
|
|
# ($uninit,$off) = thawScalar $off, $_;
|
|
# }
|
|
# $off += 3; # Hardwired offset after @2|
|
|
# }
|
|
# croak "Unknown format of frozen array: " . substr($string,$off-3)
|
|
# unless substr($string,$off-3,1) eq '@';
|
|
# my ($first,$off2) = thawScalar $off;
|
|
# my $off3;
|
|
# ($first,$off3) = thawScalar $off2;
|
|
# substr($string, $off, $off2-$off) cmp substr($string,$off2,$off3-$off2);
|
|
# }
|
|
|
|
sub FreezeThaw::FCooky::FreezeScalar {
|
|
shift;
|
|
&freezeScalar;
|
|
}
|
|
|
|
sub FreezeThaw::FCooky::isSafe {
|
|
$safe || $noCache;
|
|
}
|
|
|
|
sub FreezeThaw::FCooky::makeSafe {
|
|
$noCache = 1;
|
|
}
|
|
|
|
sub FreezeThaw::FCooky::repeatedOK {
|
|
!$norepeated;
|
|
}
|
|
|
|
sub FreezeThaw::FCooky::noRepeated {
|
|
$norepeated = 1;
|
|
}
|
|
|
|
sub FreezeThaw::TCooky::repeatedOK {
|
|
$uninitOK;
|
|
}
|
|
|
|
sub FreezeThaw::TCooky::noRepeated {
|
|
undef $uninitOK;
|
|
}
|
|
|
|
sub FreezeThaw::TCooky::isSafe {
|
|
!$unsafe;
|
|
}
|
|
|
|
sub FreezeThaw::TCooky::makeSafe {
|
|
undef $unsafe;
|
|
}
|
|
|
|
sub FreezeThaw::TCooky::ThawScalar {
|
|
my $self = shift;
|
|
my ($res,$off) = &thawScalar($$self);
|
|
$$self = $off;
|
|
$res;
|
|
}
|
|
|
|
sub UNIVERSAL::Freeze {
|
|
my ($obj, $cooky) = (shift, shift);
|
|
$cooky->FreezeScalar($obj,1,1);
|
|
}
|
|
|
|
sub UNIVERSAL::Thaw {
|
|
my ($package, $cooky) = (shift, shift);
|
|
my $obj = $cooky->ThawScalar;
|
|
bless $obj, $package;
|
|
}
|
|
|
|
sub UNIVERSAL::FreezeInstance {
|
|
my($obj,$cooky) = @_;
|
|
return if !RexIsREGEXP # Special-case non-1st-class RExes
|
|
and ref $obj and (haveIsRex ? re::is_regexp($obj)
|
|
: (ref $obj eq 'Regexp' and not defined $$obj)); # Regexp
|
|
$obj->Freeze($cooky);
|
|
}
|
|
|
|
sub UNIVERSAL::Instantiate {
|
|
my($package,$pre,$cooky) = @_;
|
|
return if !RexIsREGEXP and $package eq 'Regexp';
|
|
my $obj = $package->Thaw($cooky);
|
|
# SvAMAGIC() is a property of a reference, not of a referent!
|
|
# Thus we cannot use $pre here if $obj was overloaded...
|
|
copyContents $_[1], $obj;
|
|
}
|
|
|
|
sub UNIVERSAL::Allocate {
|
|
my($package,$cooky) = @_;
|
|
$cooky->ThawScalar;
|
|
}
|
|
|
|
sub UNIVERSAL::FreezeEmpty {
|
|
my $obj = shift;
|
|
my $type = getref $obj;
|
|
my $e = $Empty{$type};
|
|
if (ref $e) {
|
|
my $ref = &$e;
|
|
freezeScalar $ref;
|
|
$ref; # Put into cache.
|
|
} elsif ($e) {
|
|
freezeScalar($obj,1,1); # Atomic
|
|
undef;
|
|
} elsif (!RexIsREGEXP and defined $e and not defined $$obj) { # REx pre-5.11
|
|
freezeREx($obj);
|
|
undef;
|
|
} else {
|
|
die "Do not know how to FreezeEmpty $type";
|
|
}
|
|
}
|
|
|
|
1;
|