1 package DBICTest::Util::LeakTracer;
7 use Scalar::Util qw(isweak weaken blessed reftype);
8 use DBIx::Class::_Util qw(refcount hrefaddr);
9 use DBIx::Class::Optional::Dependencies;
10 use Data::Dumper::Concise;
11 use DBICTest::Util 'stacktrace';
13 CV_TRACING => DBIx::Class::Optional::Dependencies->req_ok_for ('test_leaks_heavy'),
14 SKIP_SCALAR_REFS => ( $] > 5.017 ) ? 1 : 0,
18 our @EXPORT_OK = qw(populate_weakregistry assert_empty_weakregistry visit_refs);
24 # so we don't trigger stringification
27 (defined blessed $_[0]) ? blessed($_[0]) . '=' : '',
33 sub populate_weakregistry {
34 my ($weak_registry, $target, $note) = @_;
36 croak 'Expecting a registry hashref' unless ref $weak_registry eq 'HASH';
37 croak 'Target is not a reference' unless length ref $target;
39 my $refaddr = hrefaddr $target;
41 # a registry could be fed to itself or another registry via recursive sweeps
42 return $target if $reg_of_regs{$refaddr};
44 weaken( $reg_of_regs{ hrefaddr($weak_registry) } = $weak_registry )
45 unless( $reg_of_regs{ hrefaddr($weak_registry) } );
47 # an explicit "garbage collection" pass every time we store a ref
48 # if we do not do this the registry will keep growing appearing
49 # as if the traced program is continuously slowly leaking memory
50 for my $reg (values %reg_of_regs) {
51 (defined $reg->{$_}{weakref}) or delete $reg->{$_}
55 # FIXME/INVESTIGATE - something fishy is going on with refs to plain
56 # strings, perhaps something to do with the CoW work etc...
57 return $target if SKIP_SCALAR_REFS and reftype($target) eq 'SCALAR';
59 if (! defined $weak_registry->{$refaddr}{weakref}) {
60 $weak_registry->{$refaddr} = {
61 stacktrace => stacktrace(1),
64 weaken( $weak_registry->{$refaddr}{weakref} );
68 my $desc = _describe_ref($target);
69 $weak_registry->{$refaddr}{slot_names}{$desc} = 1;
71 $note =~ s/\s*\Q$desc\E\s*//g;
72 $weak_registry->{$refaddr}{slot_names}{$note} = 1;
78 # Regenerate the slots names on a thread spawn
80 my @individual_regs = grep { scalar keys %{$_||{}} } values %reg_of_regs;
83 for my $reg (@individual_regs) {
84 my @live_slots = grep { defined $_->{weakref} } values %$reg
87 $reg = {}; # get a fresh hashref in the new thread ctx
88 weaken( $reg_of_regs{hrefaddr($reg)} = $reg );
90 for my $slot_info (@live_slots) {
91 my $new_addr = hrefaddr $slot_info->{weakref};
93 # replace all slot names
94 $slot_info->{slot_names} = { map {
96 $name =~ s/\(0x[0-9A-F]+\)/sprintf ('(%s)', $new_addr)/ieg;
98 } keys %{$slot_info->{slot_names}} };
100 $reg->{$new_addr} = $slot_info;
106 my $args = { (ref $_[0]) ? %{$_[0]} : @_ };
108 $args->{seen_refs} ||= {};
110 my $visited_cnt = '0E0';
111 for my $i (0 .. $#{$args->{refs}} ) {
113 next unless length ref $args->{refs}[$i]; # not-a-ref
115 my $addr = hrefaddr $args->{refs}[$i];
117 # no diving into weakregistries
118 next if $reg_of_regs{$addr};
120 next if $args->{seen_refs}{$addr}++;
123 my $r = $args->{refs}[$i];
125 $args->{action}->($r) or next;
127 # This may end up being necessarry some day, but do not slow things
129 #if ( defined( my $t = tied($r) ) ) {
130 # $visited_cnt += visit_refs({ %$args, refs => [ $t ] });
133 my $type = reftype $r;
137 if ($type eq 'HASH') {
138 $visited_cnt += visit_refs({ %$args, refs => [ map {
139 ( !isweak($r->{$_}) ) ? $r->{$_} : ()
142 elsif ($type eq 'ARRAY') {
143 $visited_cnt += visit_refs({ %$args, refs => [ map {
144 ( !isweak($r->[$_]) ) ? $r->[$_] : ()
147 elsif ($type eq 'REF' and !isweak($$r)) {
148 $visited_cnt += visit_refs({ %$args, refs => [ $$r ] });
150 elsif (CV_TRACING and $type eq 'CODE') {
151 $visited_cnt += visit_refs({ %$args, refs => [ map {
152 ( !isweak($_) ) ? $_ : ()
153 } scalar PadWalker::closed_over($r) ] }); # scalar due to RT#92269
156 } or warn "Could not descend into @{[ _describe_ref($r) ]}: $@\n";
161 sub visit_namespaces {
162 my $args = { (ref $_[0]) ? %{$_[0]} : @_ };
166 $args->{package} ||= '::';
167 $args->{package} = '::' if $args->{package} eq 'main';
169 if ( $args->{action}->($args->{package}) ) {
171 my $base = $args->{package};
172 $base = '' if $base eq '::';
175 $visited += visit_namespaces({ %$args, package => $_ }) for map
176 { $_ =~ /(.+?)::$/ && "${base}::$1" }
178 { $_ =~ /(?<!^main)::$/ }
179 do { no strict 'refs'; keys %{ $base . '::'} }
185 # compiles a list of addresses stored as globals (possibly even catching
186 # class data in the form of method closures), so we can skip them further on
187 sub symtable_referenced_addresses {
191 my $dummy_addresslist;
200 $pkg = '' if $pkg eq '::';
203 # the unless regex at the end skips some dangerous namespaces outright
204 # (but does not prevent descent)
205 $refs_per_pkg->{$pkg} += visit_refs (
206 seen_refs => $seen_refs,
209 # This is so damn odd - if we feed a constsub {1} (or in fact almost
210 # anything other than the actionsub below, any scalarref will show
211 # up as a leak, trapped by... something...
212 # Ideally we should be able to const this to sub{1} and just return
213 # $seen_refs (in fact it is identical to the dummy list at the end of
214 # a run here). Alas this doesn't seem to work, so punt for now...
215 action => sub { ++$dummy_addresslist->{ hrefaddr $_[0] } },
217 refs => [ map { my $sym = $_;
218 # *{"$pkg$sym"}{CODE} won't simply work - MRO-cached CVs are invisible there
219 ( CV_TRACING ? Class::MethodCache::get_cv("${pkg}$sym") : () ),
221 ( defined *{"$pkg$sym"}{SCALAR} and length ref ${"$pkg$sym"} and ! isweak( ${"$pkg$sym"} ) )
226 ( defined *{"$pkg$sym"}{$_} and ! isweak(defined *{"$pkg$sym"}{$_}) )
229 } qw(HASH ARRAY IO GLOB) ),
232 ) unless $pkg =~ /^ :: (?:
233 DB | next | B | .+? ::::ISA (?: ::CACHE ) | Class::C3
240 # { { $_ => $refs_per_pkg->{$_} } }
242 # {$refs_per_pkg->{$a} <=> $refs_per_pkg->{$b} }
243 # keys %$refs_per_pkg
249 sub assert_empty_weakregistry {
250 my ($weak_registry, $quiet) = @_;
252 # in case we hooked bless any extra object creation will wreak
253 # havoc during the assert phase
254 local *CORE::GLOBAL::bless;
255 *CORE::GLOBAL::bless = sub { CORE::bless( $_[0], (@_ > 1) ? $_[1] : caller() ) };
257 croak 'Expecting a registry hashref' unless ref $weak_registry eq 'HASH';
259 defined $weak_registry->{$_}{weakref} or delete $weak_registry->{$_}
260 for keys %$weak_registry;
262 return unless keys %$weak_registry;
264 my $tb = eval { Test::Builder->new }
265 or croak "Calling assert_empty_weakregistry in $0 without a loaded Test::Builder makes no sense";
267 for my $addr (keys %$weak_registry) {
268 $weak_registry->{$addr}{display_name} = join ' | ', (
270 { length $a <=> length $b or $a cmp $b }
271 keys %{$weak_registry->{$addr}{slot_names}}
274 $tb->BAILOUT("!!!! WEAK REGISTRY SLOT $weak_registry->{$addr}{display_name} IS NOT A WEAKREF !!!!")
275 if defined $weak_registry->{$addr}{weakref} and ! isweak( $weak_registry->{$addr}{weakref} );
278 # the walk is very expensive - if we are $quiet (running in an END block)
279 # we do not really need to be too thorough
281 delete $weak_registry->{$_} for keys %{ symtable_referenced_addresses() };
285 for my $addr (sort { $weak_registry->{$a}{display_name} cmp $weak_registry->{$b}{display_name} } keys %$weak_registry) {
287 next if ! defined $weak_registry->{$addr}{weakref};
289 $leaks_found++ unless $tb->in_todo;
290 $tb->ok (0, "Leaked $weak_registry->{$addr}{display_name}");
293 local $Data::Dumper::Maxdepth = 1;
294 sprintf "\n%s (refcnt %d) => %s\n",
295 $weak_registry->{$addr}{display_name},
296 refcount($weak_registry->{$addr}{weakref}),
298 ref($weak_registry->{$addr}{weakref}) eq 'CODE'
300 B::svref_2object($weak_registry->{$addr}{weakref})->XSUB
301 ) ? '__XSUB__' : Dumper( $weak_registry->{$addr}{weakref} )
305 # FIXME - need to add a circular reference seeker based on the visitor
306 # (will need a bunch of modifications, punting with just a stub for now)
308 $diag .= Devel::FindRef::track ($weak_registry->{$addr}{weakref}, 50) . "\n"
309 if ( $ENV{TEST_VERBOSE} && eval { require Devel::FindRef });
313 if (my $stack = $weak_registry->{$addr}{stacktrace}) {
314 $diag .= " Reference first seen$stack";
319 # if ($leaks_found == 1) {
320 # # using the fh dumper due to intermittent buffering issues
321 # # in case we decide to exit soon after (possibly via _exit)
322 # require Devel::MAT::Dumper;
323 # local $Devel::MAT::Dumper::MAX_STRING = -1;
324 # open( my $fh, '>:raw', "leaked_${addr}_pid$$.pmat" ) or die $!;
325 # Devel::MAT::Dumper::dumpfh( $fh );
326 # close ($fh) or die $!;
333 if (! $quiet and !$leaks_found and ! $tb->in_todo) {
334 $tb->ok(1, sprintf "No leaks found at %s line %d", (caller())[1,2] );
339 if ($INC{'Test/Builder.pm'}) {
340 my $tb = Test::Builder->new;
342 # we check for test passage - a leak may be a part of a TODO
343 if ($leaks_found and !$tb->is_passing) {
346 "\n\n%s\n%s\n\nInstall Devel::FindRef and re-run the test with set "
347 . '$ENV{TEST_VERBOSE} (prove -v) to see a more detailed leak-report'
348 . "\n\n%s\n%s\n\n", ('#' x 16) x 4
349 ) if ( !$ENV{TEST_VERBOSE} or !$INC{'Devel/FindRef.pm'} );
353 $tb->note("Auto checked $refs_traced references for leaks - none detected");