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require 5.006;
$VERSION = '0.13';
use Devel::Size qw(size total_size);
use Scalar::Util qw/reftype refaddr blessed dualvar isweak readonly isvstring/;
use Time::HiRes qw/time/;
use Array::RefElem qw/hv_store av_push/;
use Devel::Peek qw/SvREFCNT/;
require Exporter;
@ISA = qw/Exporter/;
@EXPORT_OK = qw/
report_size track_size element_type type entries_per_element track_sizes
hide_tracks
S_SCALAR
S_HASH
S_ARRAY
S_GLOB
S_UNKNOWN
S_CODE
S_LVALUE
S_REGEXP
S_CYCLE
S_DOUBLE
S_VSTRING
SF_WEAK
SF_KEY
SF_REF
SF_WEAK
SF_RO
SF_DUAL
SF_MAGIC
/;
use strict;
#############################################################################
# The following should not be global to be thread safe:
# If somebody used hv_store, we need also to enter hash key addresses into
# SEEN. Default is off, because this wastes memory.
my $TRACK_DOUBLES = 0;
# _track_size() stores it's result here:
my @sizes;
# for cycles in memory:
my %SEEN;
# count calls to track_size for statistics
my $CALLS;
#############################################################################
# The overhead for one ref. Used to correct the results from Devel::Size.
my $SIZE_OF_REF;
BEGIN
{
# disable any warnings Devel::Size might spill
$Devel::Size::warn = 0;
# Devel::Size will dereference arguments, so it misses the size of the
# reference. Compute the size for \\0 and \0 and infer the overhead for
# one reference from that. Thanx to SADAHIRO Tomoyuki.
$SIZE_OF_REF = total_size(\\0) - total_size(\0);
}
# scalar that can be entered into %SEEN many times:
my $UNDEF = undef;
# scalar that can be entered into @sizes many times:
my $ZERO = 0;
# the different types of elements
use constant {
S_UNKNOWN => 0,
S_CYCLE => 1,
S_SCALAR => 2,
S_ARRAY => 3,
S_HASH => 4,
S_GLOB => 5,
S_CODE => 6,
S_REGEXP => 7,
S_LVALUE => 8,
S_DOUBLE => 9,
S_VSTRING => 10 };
# some flags (to be added to the types)
use constant {
SF_KEY => 0x0100,
SF_REF => 0x0200,
SF_BLESS => 0x0400,
SF_WEAK => 0x0800,
SF_RO => 0x1000,
SF_DUAL => 0x2000,
SF_MAGIC => 0x4000 };
sub entries_per_element () { 7; }
# default mapping for type output names (human readable)
my $TYPE = {
S_SCALAR() => 'Scalar',
S_UNKNOWN() => 'Unknown',
S_HASH() => 'Hash ref',
S_GLOB() => 'Glob',
S_ARRAY() => 'Array ref',
S_CODE() => 'Code',
S_REGEXP() => 'Regexp',
S_LVALUE() => 'Lvalue',
S_CYCLE() => 'Circular ref',
S_DOUBLE() => 'Double scalar ref',
S_VSTRING() => 'VString',
SF_REF() => 'Ref',
SF_BLESS() => 'Blessed',
SF_WEAK() => 'Weak',
SF_RO() => 'Read-Only',
SF_DUAL() => 'Dual-Var',
SF_MAGIC() => 'Magical',
SF_KEY() => '',
};
# default mapping for type name (internal comparisation)
my $TYPE_CLASS = {
S_SCALAR() => 'SCALAR',
S_UNKNOWN() => 'UNKNOWN',
S_HASH() => 'HASH',
S_GLOB() => 'GLOB',
S_ARRAY() => 'ARRAY',
S_CODE() => 'CODE',
S_REGEXP() => 'REGEXP',
S_LVALUE() => 'LVALUE',
S_CYCLE() => 'CYCLE',
S_DOUBLE() => 'DOUBLE',
S_VSTRING() => 'VSTRING',
};
# map 'SCALAR' => S_SCALAR
my $NAME_MAP = {
SCALAR => S_SCALAR(),
HASH => S_HASH(),
GLOB => S_GLOB(),
ARRAY => S_ARRAY(),
CODE => S_CODE(),
REGEXP => S_REGEXP(),
LVALUE => S_LVALUE(),
CYCLE => S_CYCLE(),
DOUBLE => S_DOUBLE(),
VSTRING => S_VSTRING(),
REF => SF_REF(),
KEY => SF_KEY(),
WEAK => SF_WEAK(),
DUAL => SF_DUAL(),
RO => SF_RO(),
MAGIC => SF_MAGIC(),
};
sub _default_options
{
# set the options to their default values
my ($options) = @_;
my $o = {};
for my $k (keys %$options) { $o->{$k} = $options->{$k}; }
$o->{indent} = ' ' if !defined $o->{indent};
$o->{names} ||= $TYPE;
$o->{bytes} = 'bytes' unless defined $o->{bytes};
$o->{bytes} = ' ' . $o->{bytes} if $o->{bytes} ne '';
$o->{left} = '' if !defined $o->{left};
$o->{inner} = ' ' if !defined $o->{inner};
$o->{total} = 1 if !defined $o->{total};
$o->{head} = "Size report v$Devel::Size::Report::VERSION for" if !defined $o->{head};
$o->{overhead} = " (overhead: %i%s, %0.2f%%)" if !defined $o->{overhead};
# binary flags
for my $k (qw/addr terse class/)
{
$o->{$k} ||= 0;
}
$o;
}
sub report_size
{
# walk the given reference recursively and return text describing the size
# of each element
my ($ref,$opt) = @_;
$opt = {} unless defined $opt;
if (ref($opt) ne 'HASH')
{
require Carp;
Carp::confess ("report_size() needs a hash ref for options");
}
my $options = _default_options($opt);
$TRACK_DOUBLES = $options->{doubles} || 0;
# DONT do "track_size($ref)" because $ref is a copy of $_[0], reusing some
# pre-allocated slot and this can have a different total size than $_[0]!!
# get the size for all elements so that we can generate a report on it
track_sizes($_[0],$opt);
my $text = '';
my $indent = $options->{indent};
my $names = $options->{names};
my $bytes = $options->{bytes};
my $left = $options->{left};
my $inner = $options->{inner};
$inner .= $left;
my $total = $options->{total};
my $head = $options->{head};
my $terse = $options->{terse};
# show summary?
my $show_summary = $options->{summary};
my $foverhead = $options->{overhead};
# show class?
my $class = $options->{class};
# show addr?
my $addr = $options->{addr};
my $count = {}; # per class/element type counter
my $sum = {}; # per class/element memory sum
# XXX TODO: why not HASH here?
my $r = ref($ref); $r = '' if $r =~ /^(ARRAY|SCALAR)$/;
$r = " ($r)" if $r ne '';
$text = "$left$head '$ref'$r:\n" if $head ne '';
my $e = entries_per_element();
for (my $i = 0; $i < @sizes; $i += $e)
{
# inline element_type for speed:
# my $type = element_type( ($sizes[$i+1] & 0xFF),$names);
my $type = $names->{ ($sizes[$i+1] & 0xFF) } || 'Unknown';
if ($show_summary)
{
my $t = $sizes[$i+1] & 0xFF; $t = $TYPE_CLASS->{$t};
$t = $sizes[$i+6] if $sizes[$i+6];
print "# $t $sizes[$i+1]\n" if $t eq '_set';
if ($t)
{
$count->{$t} ++;
$sum->{$t} += $sizes[$i+2];
}
# else { should not happen }
}
if (!$terse)
{
# include flags
for my $flag (SF_WEAK, SF_RO, SF_DUAL)
{
if ( ($sizes[$i+1] & $flag) != 0)
{
$type = element_type($flag, $names) . ' ' . $type;
}
}
if ( ($sizes[$i+1] & SF_REF) != 0)
{
$type .= " " . element_type(SF_REF, $names);
}
# add addr of element if wanted
$type .= "(" . $sizes[$i+5] . ")" if $addr && $sizes[$i+5];
# add class of element if wanted
$type .= " (" . $sizes[$i+6] . ")" if $class && $sizes[$i+6];
my $str = $type;
if ( ($sizes[$i+1] & SF_KEY) != 0)
{
$str = "'$sizes[$i+4]' => " . $type;
}
$str .= " $sizes[$i+2]$bytes";
if ($sizes[$i+3] != 0)
{
my $overhead =
sprintf($foverhead, $sizes[$i+3], $bytes,
100 * $sizes[$i+3] / $sizes[$i+2]);
$overhead = ' (overhead: unknown)' if $sizes[$i+3] < 0;
$str .= $overhead;
}
$text .= $inner . ($indent x $sizes[$i]) . "$str\n";
}
}
if ($show_summary)
{
# default sort is by size
my $sort = sub { $sum->{$b} <=> $sum->{$a} };
$text .= "Total memory by class (inclusive contained elements):\n";
foreach my $k (sort $sort keys %$count)
{
$text .= $indent . _right_align($sum->{$k},10) . " bytes in " . _right_align($count->{$k},6) . " $k\n";
}
}
my $elements = scalar @sizes / $e;
$text .= $left . "Total: $sizes[2]$bytes in $elements elements\n" if $total;
hide_tracks(); # release memory
$text;
}
sub hide_tracks
{
@sizes = ();
}
sub _right_align
{
my ($txt,$len) = @_;
$txt = ' ' . $txt while (length($txt) < $len);
$txt;
}
sub element_type
{
my ($type,$TYPE) = @_;
$TYPE->{$type} || 'Unknown';
}
sub type
{
# map a typename to a type number
$NAME_MAP->{$_[0]} || S_UNKNOWN;
}
sub track_sizes
{
my $opt = $_[1];
$TRACK_DOUBLES = $opt->{doubles} || 0;
my $time = time(); # record start time
undef %SEEN; # reset cycle memory
$CALLS = 0;
@sizes = (); # reset results array & stores result:
_track_size($_[0]); # use $_[0] directly to avoid slot-reusing
if ($opt->{debug})
{
$time = time() - $time;
print STDERR "\n DEBUG: Devel::Size::Report v$Devel::Size::Report::VERSION\n";
my $size_seen = total_size(\%SEEN);
my $size_sizes = total_size(\@sizes);
print STDERR " DEBUG: \%SEEN : ", _right_align($size_seen,12), " bytes, ", scalar keys %SEEN, " elements\n";
print STDERR " DEBUG: \@sizes: ", _right_align($size_sizes,12), " bytes, ", scalar @sizes, " elements\n";
print STDERR " DEBUG: Total : ", _right_align($size_sizes + $size_seen,12), " bytes, ", scalar @sizes + scalar keys %SEEN, " elements\n";
print STDERR " DEBUG: Calls to _track_size: $CALLS\n";
print STDERR " DEBUG: took ", sprintf("%0.3f",$time), " seconds to gather data for report.\n\n";
}
undef %SEEN; # save memory, throw away
\@sizes;
}
sub track_size
{
# fill the results into @sizes
track_sizes($_[0], $_[1]);
# return a copy (backwards compatibility)
@sizes; # return results
}
sub _addr
{
# return address of an element as string
my $adr;
if (ref($_[0]) && $_[1] ne 'REF')
{
$adr = sprintf("0x%x", refaddr($_[0]));
}
else
{
$adr = sprintf("0x%x", refaddr(\($_[0])));
}
$adr;
}
sub _type
{
# find the type of an element and return as string
my $type = uc(reftype($_[0]) || '');
my $class = blessed($_[0]); $class = '' unless defined $class;
# blessed "Regexp" and ref to scalar?
$type ='REGEXP' if $class eq 'Regexp';
# refs to scalars are tricky
$type ='REF'
if ref($_[0]) && UNIVERSAL::isa($_[0],'SCALAR') && $type ne 'REGEXP';
($type,$class);
}
sub _track_size
{
# Walk the given reference recursively and store the size, type etc of each
# element
my ($ref, $level) = @_;
$level ||= 0;
$CALLS++;
no warnings 'recursion';
# DO NOT use "total_size($ref)" because $ref is a copy of $_[0], reusing some
# pre-allocated slot and this can have a different total size than $_[0]!!
my $total_size = size($_[0]);
my ($type,$blessed) = _type($_[0]);
my $adr = _addr($_[0],$type);
if (exists $SEEN{$adr})
{
# already seen this part of the world, so return
if (ref($ref))
{
push @sizes, $level, S_CYCLE, $SIZE_OF_REF, 0, undef, $adr, $blessed;
return;
}
# a scalar seen twice
push @sizes, $level, S_DOUBLE, 0, 0;
av_push (@sizes, $UNDEF);
push @sizes, $adr;
av_push (@sizes, $UNDEF);
return;
}
# put in the address of $ref in the %SEEN hash (things with a refcnt of 1
# cannot be part of a cycle, since only one thing is pointing at them)
hv_store (%SEEN, $adr , $UNDEF) if ref($_[0]) || SvREFCNT($_[0]) > 1;
# not a reference, but a plain scalar?
if (!ref($ref))
{
my $type = S_SCALAR;
$type = S_VSTRING if isvstring($_[0]);
push @sizes, $level, _flags($_[0]) + $type, $total_size;
av_push (@sizes, $ZERO);
av_push (@sizes, $UNDEF);
push @sizes, $adr, $blessed;
return;
}
my $index = scalar @sizes + 2; # idx of "total_size" entry
if ($type eq 'ARRAY')
{
push @sizes, $level, S_ARRAY, $total_size + $SIZE_OF_REF, 0, undef, $adr, $blessed;
my $sum = 0;
for (my $i = 0; $i < scalar @$ref; $i++)
{
my $adr = _addr($ref->[$i], _type($ref->[$i]));
if (exists $SEEN{$adr} || ref($ref->[$i]))
{
my $index = scalar @sizes;
_track_size($ref->[$i], $level+1);
$sum += $sizes[$index+2];
}
else
{
# Put in the address of $ref in the %SEEN hash.
# If TRACK_DOUBLES is set, we also need to store scalars with
# REFCNT == 1 because somebody might have used hv_store() to make all
# keys point to the same scalar and these "shared" scalars have
# unfortunately a REFCNT of 1.
hv_store (%SEEN, $adr , $UNDEF) if $TRACK_DOUBLES || SvREFCNT($_[0]) > 1;
my $size = size($ref->[$i]);
push @sizes, $level+1, S_SCALAR, $size;
av_push (@sizes, $ZERO);
av_push (@sizes, $UNDEF);
push @sizes, $adr;
av_push (@sizes, $UNDEF);
$sum += $size;
}
}
$sizes[$index] += $sum;
$sizes[$index+1] = $sizes[$index] - $sum;
}
elsif ($type eq 'HASH')
{
push @sizes, $level, S_HASH, $total_size + $SIZE_OF_REF, 0, undef, $adr, $blessed;
my $sum = 0;
foreach my $elem ( keys %$ref )
{
my $adr = _addr($ref->{$elem}, _type($ref->{$elem}));
if (exists $SEEN{$adr} || ref($ref->{$elem}))
{
my $index = scalar @sizes;
_track_size($ref->{$elem},$level+1);
$sizes[$index+1] += SF_KEY;
$sizes[$index+4] = $elem;
$sum += $sizes[$index+2];
}
else
{
# Put in the address of $ref in the %SEEN hash.
# If TRACK_DOUBLES is set, we also need to store scalars with
# REFCNT == 1 because somebody might have used hv_store() to make all
# keys point to the same scalar and these "shared" scalars have
# unfortunately a REFCNT of 1.
hv_store (%SEEN, $adr , $UNDEF) if $TRACK_DOUBLES || SvREFCNT($_[0]) > 1;
my $size = size($ref->{$elem});
push @sizes, $level+1, SF_KEY + S_SCALAR, $size, 0, $elem, $adr, undef;
$sum += $size;
}
}
$sizes[$index] += $sum;
$sizes[$index+1] = $sizes[$index] - $sum;
}
elsif ($type eq 'REGEXP')
{
push @sizes, $level, type($type), $total_size;
av_push (@sizes, $ZERO);
av_push (@sizes, $UNDEF);
push @sizes, $adr, $blessed;
}
elsif ($type eq 'REF')
{
my $type = uc(reftype(${$_[0]}) || '');
$type ='REGEXP' if $blessed eq 'Regexp';
$type ='SCALAR' if !ref(${$_[0]});
my $flags = SF_REF;
$flags += SF_WEAK if isweak($_[0]);
push @sizes,
($level, $flags + type($type), $total_size, 0, undef, $adr, $blessed);
_track_size($$ref,$level+1);
$sizes[$index] += $SIZE_OF_REF; # account for wrong \"" sizes
$sizes[$index+1] = $sizes[$index] - total_size($$ref);
}
# SCALAR reference must come after Regexp, because these are also SCALAR !?
elsif ($type eq 'SCALAR')
{
push @sizes, ($level, SF_REF, $total_size, 0, undef, $adr, $blessed);
}
else
{
my $overhead = 0;
$overhead = -1 if type($type) == S_UNKNOWN;
push @sizes, ($level, type($type), $total_size, $overhead, undef, $adr, $blessed);
}
}
sub _flags
{
my $flags = 0;
$flags += SF_RO if readonly($_[0]);
$flags += SF_WEAK if isweak($_[0]);
# XXX TODO: how to find out if something is:
# an LVALUE
# a DUALVAR
# a STASH
$flags;
}
1;
__END__
=pod
=head1 NAME
Devel::Size::Report - generate a size report for all elements in a structure
=head1 SYNOPSIS
use Devel::Size::Report qw/report_size/;
my $a = [ \8, \*STDIN, 7,
[ 1, 2, 3,
{ a => 'b',
size => 12.2,
h => ['a']
},
'rrr'
]
];
print report_size($a, { indent => " " } );
This will print something like this:
Size report v0.08 for 'ARRAY(0x8145e6c)':
Array 886 bytes (overhead: 100 bytes, 11.29%)
Scalar Ref 32 bytes (overhead: 16 bytes, 50.00%)
Read-Only Scalar 16 bytes
Glob 266 bytes
Scalar 16 bytes
Array 472 bytes (overhead: 88 bytes, 18.64%)
Scalar 16 bytes
Scalar 16 bytes
Scalar 16 bytes
Hash 308 bytes (overhead: 180 bytes, 58.44%)
'h' => Array 82 bytes (overhead: 56 bytes, 68.29%)
Scalar 26 bytes
'a' => Scalar 26 bytes
'size' => Scalar 20 bytes
Scalar 28 bytes
Total: 886 bytes in 15 elements
=head1 EXPORTS
Nothing per default, but can export the following per request:
report_size
track_size
track_sizes
hide_tracks
element_type
entries_per_element
S_SCALAR
S_HASH
S_ARRAY
S_GLOB
S_UNKNOWN
S_CODE
S_LVALUE
S_REGEXP
S_CYCLE
S_DOUBLE
SF_KEY
SF_REF
SF_REF
SF_WEAK
SF_RO
SF_VSTRING
SF_DUAL
=head1 DESCRIPTION
Devel::Size can only report the size of a single element or the total size of
a structure (array, hash etc). This module enhances Devel::Size by giving you
the ability to generate a full size report for each element in a structure.
You have full control over how the generated text report looks like, and where
you want to output it. In addition, the method C<track_size> allows you to get
at the raw data that is used to generate the report for even more flexibility.
=head1 METHODS
=head2 report_size
my $record = report_size( $reference, $options ) . "\n";
print $record;
Walks the given reference recursively and returns text tree describing
the size of each element. C<$options> is a hash, containing the following
optional keys:
names ref to HASH mapping the types to names
This should map S_Scalar to something like "Scalar" etc
indent string to indent different levels with, default is ' '
left indent all text with this at the left side, default is ''
inner indent inner text with this at the left side, default is ' '
total if true, a total size will be printed as last line
bytes name of the size unit, defaults to 'bytes'
head header string, default 'Size report for'
Set to '' to supress header completely
overhead Format string for the overhead, first size in bytes, then
the bytes string (see above) and then the percentage.
The default is:
" (overhead: %i%s, %0.2f%%)"
addr if true, for each element the memory address will be output
class if true, show the class each element was blessed in
terse if true, details for elements will be supressed, e.g. you
will only get the header, total and summary (if requested)
summary if true, print a table summing up the memory details on a
per-class basis
doubles If true, hash keys and array elemts that point to the same
thing in memory will be reported. Default is off, since it
saves memory. Note that you will usually only get double
entries in hashes and array by using Array::RefElem's methods
or similiar hacks/tricks.
=head2 entries_per_element
my $entries = entries_per_element();
Returns the number of entries per element that L<track_size()> will generate.
=head2 track_sizes
$elements = track_sizes( $reference, $level);
Walk the given scalar or reference recursively and returns a ref to an array,
containing L<entries_per_element> entries for each element in the structure
pointed to by C<$reference>. C<$reference> can also be a plain scalar.
The entries for each element are currently:
level the indent level
type the type of the element, S_SCALAR, S_HASH, S_ARRAY etc
if (type & SF_KEY) != 0, the element is a member of a hash
size size in bytes of the element
overhead if the element is an ARRAY or HASH, contains the overhead
in bytes (size - sum(size of all elements)).
name if type & SF_KEY != 0, this contains the name of the hash key
addr memory address of the element
class classname that the element was blessed into, or ''
=head2 track_size
@elements = track_size( $reference, $level);
Works just like L<track_sizes>, but for backward compatibility reasons
returns an array with the results.
=head2 hide_tracks
hide_tracks();
Releases the memory consumed by a call to L<track_size> or L<track_sizes>.
=head2 type
$type_number = type($type_name);
Maps a type name (like 'SCALAR') to a type number (lilke S_SCALAR).
=head2 element_type
$type_name = element_type($type_nr);
Maps a type number (like S_SCALAR) to a type name (lilke 'SCALAR').
=head1 WRAP YOUR OWN
If you want to create your own report with different formattings, please
use L<track_size> and create a report out of the data you get back from it.
Look at the source code for L<report_size> how to do this - it is easy!
=head1 CAVEATS
=over 2
=item *
The limitations of Devel::Size also apply to this module. This means that
CODE refs and other "obscure" things might show wrong sizes, or unknown
overhead. In addition, some sizes might be reported wrong.
=item *
A string representation of the passed argument will be inserted when generating
a report with a header.
If the passed argument is an object with overloaded magic, then the routine for
stringification will be triggered. If this routine does actually modify the
object (for instance, Math::String objects cache their string form upon first
call to stringification, thus modifying themselves), the reported size will be
different from a first report without a header.
=back
=head1 BUGS
=over 4
=item threads
The results are currently stored in a global package var, so this is probably
not threadsafe.
=back
=head1 AUTHOR
(c) 2004, 2005, 2006, 2008 by Tels http://bloodgate.com
=cut