← Index
NYTProf Performance Profile   « block view • line view • sub view »
For ddd2.pl
  Run on Tue May 25 16:52:24 2010
Reported on Tue May 25 16:56:45 2010

File /project/perl/lib/XSLoader.pm
Statements Executed 0
Statement Execution Time 0s
Subroutines — ordered by exclusive time
Calls P F Exclusive
Time		 Inclusive
Time		 Subroutine
77719.8ms19.8msXSLoader::::loadXSLoader::load
0000s0sXSLoader::::bootstrap_inheritXSLoader::bootstrap_inherit
Call graph for these subroutines as a Graphviz dot language file.
Line State
ments		 Time
on line		 Calls Time
in subs		 Code
1# Generated from XSLoader.pm.PL (resolved %Config::Config value)
2
3package XSLoader;
4
5$VERSION = "0.08";
6
7#use strict;
8
9# enable debug/trace messages from DynaLoader perl code
10# $dl_debug = $ENV{PERL_DL_DEBUG} || 0 unless defined $dl_debug;
11
12 my $dl_dlext = 'so';
13
14package DynaLoader;
15
16# No prizes for guessing why we don't say 'bootstrap DynaLoader;' here.
17# NOTE: All dl_*.xs (including dl_none.xs) define a dl_error() XSUB
18boot_DynaLoader('DynaLoader') if defined(&boot_DynaLoader) &&
19 !defined(&dl_error);
20package XSLoader;
21
22
# spent 19.8ms within XSLoader::load which was called 7 times, avg 2.83ms/call: # once (16.8ms+0s) by LWP::Protocol::collect at line 17 of HTML/Parser.pm # once (792µs+0s) by Net::HTTP::Methods::zlib_ok at line 85 of Compress/Raw/Zlib.pm # once (522µs+0s) by base::import at line 11 of IO.pm # once (474µs+0s) by base::import at line 27 of List/Util.pm # once (412µs+0s) by Net::HTTP::Methods::zlib_ok at line 96 of File/Glob.pm # once (400µs+0s) by LWP::Protocol::implementor at line 399 of Socket.pm # once (355µs+0s) by base::import at line 234 of Fcntl.pm
sub load {
23 package DynaLoader;
24
25 die q{XSLoader::load('Your::Module', $Your::Module::VERSION)} unless @_;
26
27 my($module) = $_[0];
28
29 # work with static linking too
30 my $b = "$module\::bootstrap";
31 goto &$b if defined &$b;
32
33 goto retry unless $module and defined &dl_load_file;
34
35 my @modparts = split(/::/,$module);
36 my $modfname = $modparts[-1];
37
38 my $modpname = join('/',@modparts);
39 my $modlibname = (caller())[1];
40 my $c = @modparts;
41 $modlibname =~ s,[\\/][^\\/]+$,, while $c--; # Q&D basename
42 my $file = "$modlibname/auto/$modpname/$modfname.$dl_dlext";
43
44# print STDERR "XSLoader::load for $module ($file)\n" if $dl_debug;
45
46 my $bs = $file;
47 $bs =~ s/(\.\w+)?(;\d*)?$/\.bs/; # look for .bs 'beside' the library
48
49 goto retry if not -f $file or -s $bs;
50
51 my $bootname = "boot_$module";
52 $bootname =~ s/\W/_/g;
53 @DynaLoader::dl_require_symbols = ($bootname);
54
55 my $boot_symbol_ref;
56
57 # Many dynamic extension loading problems will appear to come from
58 # this section of code: XYZ failed at line 123 of DynaLoader.pm.
59 # Often these errors are actually occurring in the initialisation
60 # C code of the extension XS file. Perl reports the error as being
61 # in this perl code simply because this was the last perl code
62 # it executed.
63
64 my $libref = dl_load_file($file, 0) or do {
65 require Carp;
66 Carp::croak("Can't load '$file' for module $module: " . dl_error());
67 };
68 push(@DynaLoader::dl_librefs,$libref); # record loaded object
69
70 my @unresolved = dl_undef_symbols();
71 if (@unresolved) {
72 require Carp;
73 Carp::carp("Undefined symbols present after loading $file: @unresolved\n");
74 }
75
76 $boot_symbol_ref = dl_find_symbol($libref, $bootname) or do {
77 require Carp;
78 Carp::croak("Can't find '$bootname' symbol in $file\n");
79 };
80
81 push(@DynaLoader::dl_modules, $module); # record loaded module
82
83 boot:
84 my $xs = dl_install_xsub("${module}::bootstrap", $boot_symbol_ref, $file);
85
86 # See comment block above
87 push(@DynaLoader::dl_shared_objects, $file); # record files loaded
88 return &$xs(@_);
89
90 retry:
91 my $bootstrap_inherit = DynaLoader->can('bootstrap_inherit') ||
92 XSLoader->can('bootstrap_inherit');
93 goto &$bootstrap_inherit;
94}
95
96# Versions of DynaLoader prior to 5.6.0 don't have this function.
97sub bootstrap_inherit {
98 package DynaLoader;
99
100 my $module = $_[0];
101 local *DynaLoader::isa = *{"$module\::ISA"};
102 local @DynaLoader::isa = (@DynaLoader::isa, 'DynaLoader');
103 # Cannot goto due to delocalization. Will report errors on a wrong line?
104 require DynaLoader;
105 DynaLoader::bootstrap(@_);
106}
107
1081;
109
110
111__END__
112
113=head1 NAME
114
115XSLoader - Dynamically load C libraries into Perl code
116
117=head1 VERSION
118
119Version 0.08
120
121=head1 SYNOPSIS
122
123 package YourPackage;
124 use XSLoader;
125
126 XSLoader::load 'YourPackage', $YourPackage::VERSION;
127
128=head1 DESCRIPTION
129
130This module defines a standard I<simplified> interface to the dynamic
131linking mechanisms available on many platforms. Its primary purpose is
132to implement cheap automatic dynamic loading of Perl modules.
133
134For a more complicated interface, see L<DynaLoader>. Many (most)
135features of C<DynaLoader> are not implemented in C<XSLoader>, like for
136example the C<dl_load_flags>, not honored by C<XSLoader>.
137
138=head2 Migration from C<DynaLoader>
139
140A typical module using L<DynaLoader|DynaLoader> starts like this:
141
142 package YourPackage;
143 require DynaLoader;
144
145 our @ISA = qw( OnePackage OtherPackage DynaLoader );
146 our $VERSION = '0.01';
147 bootstrap YourPackage $VERSION;
148
149Change this to
150
151 package YourPackage;
152 use XSLoader;
153
154 our @ISA = qw( OnePackage OtherPackage );
155 our $VERSION = '0.01';
156 XSLoader::load 'YourPackage', $VERSION;
157
158In other words: replace C<require DynaLoader> by C<use XSLoader>, remove
159C<DynaLoader> from C<@ISA>, change C<bootstrap> by C<XSLoader::load>. Do not
160forget to quote the name of your package on the C<XSLoader::load> line,
161and add comma (C<,>) before the arguments (C<$VERSION> above).
162
163Of course, if C<@ISA> contained only C<DynaLoader>, there is no need to have
164the C<@ISA> assignment at all; moreover, if instead of C<our> one uses the
165more backward-compatible
166
167 use vars qw($VERSION @ISA);
168
169one can remove this reference to C<@ISA> together with the C<@ISA> assignment.
170
171If no C<$VERSION> was specified on the C<bootstrap> line, the last line becomes
172
173 XSLoader::load 'YourPackage';
174
175=head2 Backward compatible boilerplate
176
177If you want to have your cake and eat it too, you need a more complicated
178boilerplate.
179
180 package YourPackage;
181 use vars qw($VERSION @ISA);
182
183 @ISA = qw( OnePackage OtherPackage );
184 $VERSION = '0.01';
185 eval {
186 require XSLoader;
187 XSLoader::load('YourPackage', $VERSION);
188 1;
189 } or do {
190 require DynaLoader;
191 push @ISA, 'DynaLoader';
192 bootstrap YourPackage $VERSION;
193 };
194
195The parentheses about C<XSLoader::load()> arguments are needed since we replaced
196C<use XSLoader> by C<require>, so the compiler does not know that a function
197C<XSLoader::load()> is present.
198
199This boilerplate uses the low-overhead C<XSLoader> if present; if used with
200an antic Perl which has no C<XSLoader>, it falls back to using C<DynaLoader>.
201
202=head1 Order of initialization: early load()
203
204I<Skip this section if the XSUB functions are supposed to be called from other
205modules only; read it only if you call your XSUBs from the code in your module,
206or have a C<BOOT:> section in your XS file (see L<perlxs/"The BOOT: Keyword">).
207What is described here is equally applicable to the L<DynaLoader|DynaLoader>
208interface.>
209
210A sufficiently complicated module using XS would have both Perl code (defined
211in F<YourPackage.pm>) and XS code (defined in F<YourPackage.xs>). If this
212Perl code makes calls into this XS code, and/or this XS code makes calls to
213the Perl code, one should be careful with the order of initialization.
214
215The call to C<XSLoader::load()> (or C<bootstrap()>) has three side effects:
216
217=over
218
219=item *
220
221if C<$VERSION> was specified, a sanity check is done to ensure that the
222versions of the F<.pm> and the (compiled) F<.xs> parts are compatible;
223
224=item *
225
226the XSUBs are made accessible from Perl;
227
228=item *
229
230if a C<BOOT:> section was present in the F<.xs> file, the code there is called.
231
232=back
233
234Consequently, if the code in the F<.pm> file makes calls to these XSUBs, it is
235convenient to have XSUBs installed before the Perl code is defined; for
236example, this makes prototypes for XSUBs visible to this Perl code.
237Alternatively, if the C<BOOT:> section makes calls to Perl functions (or
238uses Perl variables) defined in the F<.pm> file, they must be defined prior to
239the call to C<XSLoader::load()> (or C<bootstrap()>).
240
241The first situation being much more frequent, it makes sense to rewrite the
242boilerplate as
243
244 package YourPackage;
245 use XSLoader;
246 use vars qw($VERSION @ISA);
247
248 BEGIN {
249 @ISA = qw( OnePackage OtherPackage );
250 $VERSION = '0.01';
251
252 # Put Perl code used in the BOOT: section here
253
254 XSLoader::load 'YourPackage', $VERSION;
255 }
256
257 # Put Perl code making calls into XSUBs here
258
259=head2 The most hairy case
260
261If the interdependence of your C<BOOT:> section and Perl code is
262more complicated than this (e.g., the C<BOOT:> section makes calls to Perl
263functions which make calls to XSUBs with prototypes), get rid of the C<BOOT:>
264section altogether. Replace it with a function C<onBOOT()>, and call it like
265this:
266
267 package YourPackage;
268 use XSLoader;
269 use vars qw($VERSION @ISA);
270
271 BEGIN {
272 @ISA = qw( OnePackage OtherPackage );
273 $VERSION = '0.01';
274 XSLoader::load 'YourPackage', $VERSION;
275 }
276
277 # Put Perl code used in onBOOT() function here; calls to XSUBs are
278 # prototype-checked.
279
280 onBOOT;
281
282 # Put Perl initialization code assuming that XS is initialized here
283
284
285=head1 DIAGNOSTICS
286
287=over
288
289=item C<Can't find '%s' symbol in %s>
290
291B<(F)> The bootstrap symbol could not be found in the extension module.
292
293=item C<Can't load '%s' for module %s: %s>
294
295B<(F)> The loading or initialisation of the extension module failed.
296The detailed error follows.
297
298=item C<Undefined symbols present after loading %s: %s>
299
300B<(W)> As the message says, some symbols stay undefined although the
301extension module was correctly loaded and initialised. The list of undefined
302symbols follows.
303
304=item C<XSLoader::load('Your::Module', $Your::Module::VERSION)>
305
306B<(F)> You tried to invoke C<load()> without any argument. You must supply
307a module name, and optionally its version.
308
309=back
310
311
312=head1 LIMITATIONS
313
314To reduce the overhead as much as possible, only one possible location
315is checked to find the extension DLL (this location is where C<make install>
316would put the DLL). If not found, the search for the DLL is transparently
317delegated to C<DynaLoader>, which looks for the DLL along the C<@INC> list.
318
319In particular, this is applicable to the structure of C<@INC> used for testing
320not-yet-installed extensions. This means that running uninstalled extensions
321may have much more overhead than running the same extensions after
322C<make install>.
323
324
325=head1 BUGS
326
327Please report any bugs or feature requests via the perlbug(1) utility.
328
329
330=head1 SEE ALSO
331
332L<DynaLoader>
333
334
335=head1 AUTHORS
336
337Ilya Zakharevich originally extracted C<XSLoader> from C<DynaLoader>.
338
339CPAN version is currently maintained by SE<eacute>bastien Aperghis-Tramoni
340E<lt>sebastien@aperghis.netE<gt>.
341
342Previous maintainer was Michael G Schwern <schwern@pobox.com>.
343
344
345=head1 COPYRIGHT
346
347This program is free software; you can redistribute it and/or modify
348it under the same terms as Perl itself.
349
350=cut
Report produced by the NYTProf 3.11 Perl profiler, developed by Tim Bunce and Adam Kaplan.