Profile of XSLoader.pm

← Index
NYTProf Performance Profile «line view»
For -e
Run on Thu Jun 30 16:34:56 2016
Reported on Thu Jun 30 16:35:09 2016

Filename | /home/s1/perl5/perlbrew/perls/perl-5.22.1/lib/5.22.1/XSLoader.pm
Statements | Executed 0 statements in 0s

Subroutines
Calls | P | F | Exclusive Time | Inclusive Time | Subroutine
--- | --- | --- | --- | --- | ---
8 | 8 | 8 | 2.52ms | 2.52ms | XSLoader::::loadXSLoader::load
0 | 0 | 0 | 0s | 0s | XSLoader::::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 |  |  |  |  |
3 |  |  |  |  | package XSLoader;
4 |  |  |  |  |
5 |  |  |  |  | $VERSION = "0.20";
6 |  |  |  |  |
7 |  |  |  |  | #use strict;
8 |  |  |  |  |
9 |  |  |  |  | package DynaLoader;
10 |  |  |  |  |
11 |  |  |  |  | # No prizes for guessing why we don't say 'bootstrap DynaLoader;' here.
12 |  |  |  |  | # NOTE: All dl_*.xs (including dl_none.xs) define a dl_error() XSUB
13 |  |  |  |  | boot_DynaLoader('DynaLoader') if defined(&boot_DynaLoader) &&
14 |  |  |  |  | !defined(&dl_error);
15 |  |  |  |  | package XSLoader;
16 |  |  |  |  |
17 |  |  |  |  | # spent 2.52ms within XSLoader::load which was called 8 times, avg 315µs/call: # once (533µs+0s) by DateTime::BEGIN@18 at line 36 of POSIX.pm # once (440µs+0s) by POSIX::BEGIN@11 at line 66 of Fcntl.pm # once (315µs+0s) by Class::Inspector::BEGIN@47 at line 17 of File/Spec/Unix.pm # once (315µs+0s) by DateTime::Helpers::BEGIN@8 at line 23 of List/Util.pm # once (312µs+0s) by DateTime::Format::Alami::BEGIN@114 at line 88 of re.pm # once (207µs+0s) by Module::Runtime::require_module at line 42 of Params/Validate/XS.pm # once (203µs+0s) by version::BEGIN@1 at line 14 of version/vxs.pm # once (200µs+0s) by DateTime::try {...} at line 30 of DateTime.pm sub load {
18 |  |  |  |  | package DynaLoader;
19 |  |  |  |  |
20 |  |  |  |  | my ($caller, $modlibname) = caller();
21 |  |  |  |  | my $module = $caller;
22 |  |  |  |  |
23 |  |  |  |  | if (@_) {
24 |  |  |  |  | $module = $_[0];
25 |  |  |  |  | } else {
26 |  |  |  |  | $_[0] = $module;
27 |  |  |  |  | }
28 |  |  |  |  |
29 |  |  |  |  | # work with static linking too
30 |  |  |  |  | my $boots = "$module\::bootstrap";
31 |  |  |  |  | goto &$boots if defined &$boots;
32 |  |  |  |  |
33 |  |  |  |  | goto \&XSLoader::bootstrap_inherit 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 $c = () = split(/::/,$caller,-1);
40 |  |  |  |  | $modlibname =~ s,[\\/][^\\/]+$,, while $c--; # Q&D basename
41 |  |  |  |  | my $file = "$modlibname/auto/$modpname/$modfname.so";
42 |  |  |  |  |
43 |  |  |  |  | # print STDERR "XSLoader::load for $module ($file)\n" if $dl_debug;
44 |  |  |  |  |
45 |  |  |  |  | my $bs = $file;
46 |  |  |  |  | $bs =~ s/(\.\w+)?(;\d*)?$/\.bs/; # look for .bs 'beside' the library
47 |  |  |  |  |
48 |  |  |  |  | if (-s $bs) { # only read file if it's not empty
49 |  |  |  |  | # print STDERR "BS: $bs ($^O, $dlsrc)\n" if $dl_debug;
50 |  |  |  |  | eval { do $bs; };
51 |  |  |  |  | warn "$bs: $@\n" if $@;
52 |  |  |  |  | goto \&XSLoader::bootstrap_inherit;
53 |  |  |  |  | }
54 |  |  |  |  |
55 |  |  |  |  | goto \&XSLoader::bootstrap_inherit if not -f $file;
56 |  |  |  |  |
57 |  |  |  |  | my $bootname = "boot_$module";
58 |  |  |  |  | $bootname =~ s/\W/_/g;
59 |  |  |  |  | @DynaLoader::dl_require_symbols = ($bootname);
60 |  |  |  |  |
61 |  |  |  |  | my $boot_symbol_ref;
62 |  |  |  |  |
63 |  |  |  |  | # Many dynamic extension loading problems will appear to come from
64 |  |  |  |  | # this section of code: XYZ failed at line 123 of DynaLoader.pm.
65 |  |  |  |  | # Often these errors are actually occurring in the initialisation
66 |  |  |  |  | # C code of the extension XS file. Perl reports the error as being
67 |  |  |  |  | # in this perl code simply because this was the last perl code
68 |  |  |  |  | # it executed.
69 |  |  |  |  |
70 |  |  |  |  | my $libref = dl_load_file($file, 0) or do {
71 |  |  |  |  | require Carp;
72 |  |  |  |  | Carp::croak("Can't load '$file' for module $module: " . dl_error());
73 |  |  |  |  | };
74 |  |  |  |  | push(@DynaLoader::dl_librefs,$libref); # record loaded object
75 |  |  |  |  |
76 |  |  |  |  | my @unresolved = dl_undef_symbols();
77 |  |  |  |  | if (@unresolved) {
78 |  |  |  |  | require Carp;
79 |  |  |  |  | Carp::carp("Undefined symbols present after loading $file: @unresolved\n");
80 |  |  |  |  | }
81 |  |  |  |  |
82 |  |  |  |  | $boot_symbol_ref = dl_find_symbol($libref, $bootname) or do {
83 |  |  |  |  | require Carp;
84 |  |  |  |  | Carp::croak("Can't find '$bootname' symbol in $file\n");
85 |  |  |  |  | };
86 |  |  |  |  |
87 |  |  |  |  | push(@DynaLoader::dl_modules, $module); # record loaded module
88 |  |  |  |  |
89 |  |  |  |  | boot:
90 |  |  |  |  | my $xs = dl_install_xsub($boots, $boot_symbol_ref, $file);
91 |  |  |  |  |
92 |  |  |  |  | # See comment block above
93 |  |  |  |  | push(@DynaLoader::dl_shared_objects, $file); # record files loaded
94 |  |  |  |  | return &$xs(@_);
95 |  |  |  |  | }
96 |  |  |  |  |
97 |  |  |  |  | sub bootstrap_inherit {
98 |  |  |  |  | require DynaLoader;
99 |  |  |  |  | goto \&DynaLoader::bootstrap_inherit;
100 |  |  |  |  | }
101 |  |  |  |  |
102 |  |  |  |  | 1;
103 |  |  |  |  |
104 |  |  |  |  |
105 |  |  |  |  | __END__
106 |  |  |  |  |
107 |  |  |  |  | =head1 NAME
108 |  |  |  |  |
109 |  |  |  |  | XSLoader - Dynamically load C libraries into Perl code
110 |  |  |  |  |
111 |  |  |  |  | =head1 VERSION
112 |  |  |  |  |
113 |  |  |  |  | Version 0.17
114 |  |  |  |  |
115 |  |  |  |  | =head1 SYNOPSIS
116 |  |  |  |  |
117 |  |  |  |  | package YourPackage;
118 |  |  |  |  | require XSLoader;
119 |  |  |  |  |
120 |  |  |  |  | XSLoader::load();
121 |  |  |  |  |
122 |  |  |  |  | =head1 DESCRIPTION
123 |  |  |  |  |
124 |  |  |  |  | This module defines a standard I<simplified> interface to the dynamic
125 |  |  |  |  | linking mechanisms available on many platforms. Its primary purpose is
126 |  |  |  |  | to implement cheap automatic dynamic loading of Perl modules.
127 |  |  |  |  |
128 |  |  |  |  | For a more complicated interface, see L<DynaLoader>. Many (most)
129 |  |  |  |  | features of C<DynaLoader> are not implemented in C<XSLoader>, like for
130 |  |  |  |  | example the C<dl_load_flags>, not honored by C<XSLoader>.
131 |  |  |  |  |
132 |  |  |  |  | =head2 Migration from C<DynaLoader>
133 |  |  |  |  |
134 |  |  |  |  | A typical module using L<DynaLoader|DynaLoader> starts like this:
135 |  |  |  |  |
136 |  |  |  |  | package YourPackage;
137 |  |  |  |  | require DynaLoader;
138 |  |  |  |  |
139 |  |  |  |  | our @ISA = qw( OnePackage OtherPackage DynaLoader );
140 |  |  |  |  | our $VERSION = '0.01';
141 |  |  |  |  | bootstrap YourPackage $VERSION;
142 |  |  |  |  |
143 |  |  |  |  | Change this to
144 |  |  |  |  |
145 |  |  |  |  | package YourPackage;
146 |  |  |  |  | use XSLoader;
147 |  |  |  |  |
148 |  |  |  |  | our @ISA = qw( OnePackage OtherPackage );
149 |  |  |  |  | our $VERSION = '0.01';
150 |  |  |  |  | XSLoader::load 'YourPackage', $VERSION;
151 |  |  |  |  |
152 |  |  |  |  | In other words: replace C<require DynaLoader> by C<use XSLoader>, remove
153 |  |  |  |  | C<DynaLoader> from C<@ISA>, change C<bootstrap> by C<XSLoader::load>. Do not
154 |  |  |  |  | forget to quote the name of your package on the C<XSLoader::load> line,
155 |  |  |  |  | and add comma (C<,>) before the arguments (C<$VERSION> above).
156 |  |  |  |  |
157 |  |  |  |  | Of course, if C<@ISA> contained only C<DynaLoader>, there is no need to have
158 |  |  |  |  | the C<@ISA> assignment at all; moreover, if instead of C<our> one uses the
159 |  |  |  |  | more backward-compatible
160 |  |  |  |  |
161 |  |  |  |  | use vars qw($VERSION @ISA);
162 |  |  |  |  |
163 |  |  |  |  | one can remove this reference to C<@ISA> together with the C<@ISA> assignment.
164 |  |  |  |  |
165 |  |  |  |  | If no C<$VERSION> was specified on the C<bootstrap> line, the last line becomes
166 |  |  |  |  |
167 |  |  |  |  | XSLoader::load 'YourPackage';
168 |  |  |  |  |
169 |  |  |  |  | If the call to C<load> is from C<YourPackage>, then that can be further
170 |  |  |  |  | simplified to
171 |  |  |  |  |
172 |  |  |  |  | XSLoader::load();
173 |  |  |  |  |
174 |  |  |  |  | as C<load> will use C<caller> to determine the package.
175 |  |  |  |  |
176 |  |  |  |  | =head2 Backward compatible boilerplate
177 |  |  |  |  |
178 |  |  |  |  | If you want to have your cake and eat it too, you need a more complicated
179 |  |  |  |  | boilerplate.
180 |  |  |  |  |
181 |  |  |  |  | package YourPackage;
182 |  |  |  |  | use vars qw($VERSION @ISA);
183 |  |  |  |  |
184 |  |  |  |  | @ISA = qw( OnePackage OtherPackage );
185 |  |  |  |  | $VERSION = '0.01';
186 |  |  |  |  | eval {
187 |  |  |  |  | require XSLoader;
188 |  |  |  |  | XSLoader::load('YourPackage', $VERSION);
189 |  |  |  |  | 1;
190 |  |  |  |  | } or do {
191 |  |  |  |  | require DynaLoader;
192 |  |  |  |  | push @ISA, 'DynaLoader';
193 |  |  |  |  | bootstrap YourPackage $VERSION;
194 |  |  |  |  | };
195 |  |  |  |  |
196 |  |  |  |  | The parentheses about C<XSLoader::load()> arguments are needed since we replaced
197 |  |  |  |  | C<use XSLoader> by C<require>, so the compiler does not know that a function
198 |  |  |  |  | C<XSLoader::load()> is present.
199 |  |  |  |  |
200 |  |  |  |  | This boilerplate uses the low-overhead C<XSLoader> if present; if used with
201 |  |  |  |  | an antique Perl which has no C<XSLoader>, it falls back to using C<DynaLoader>.
202 |  |  |  |  |
203 |  |  |  |  | =head1 Order of initialization: early load()
204 |  |  |  |  |
205 |  |  |  |  | I<Skip this section if the XSUB functions are supposed to be called from other
206 |  |  |  |  | modules only; read it only if you call your XSUBs from the code in your module,
207 |  |  |  |  | or have a C<BOOT:> section in your XS file (see L<perlxs/"The BOOT: Keyword">).
208 |  |  |  |  | What is described here is equally applicable to the L<DynaLoader|DynaLoader>
209 |  |  |  |  | interface.>
210 |  |  |  |  |
211 |  |  |  |  | A sufficiently complicated module using XS would have both Perl code (defined
212 |  |  |  |  | in F<YourPackage.pm>) and XS code (defined in F<YourPackage.xs>). If this
213 |  |  |  |  | Perl code makes calls into this XS code, and/or this XS code makes calls to
214 |  |  |  |  | the Perl code, one should be careful with the order of initialization.
215 |  |  |  |  |
216 |  |  |  |  | The call to C<XSLoader::load()> (or C<bootstrap()>) calls the module's
217 |  |  |  |  | bootstrap code. For modules build by F<xsubpp> (nearly all modules) this
218 |  |  |  |  | has three side effects:
219 |  |  |  |  |
220 |  |  |  |  | =over
221 |  |  |  |  |
222 |  |  |  |  | =item *
223 |  |  |  |  |
224 |  |  |  |  | A sanity check is done to ensure that the versions of the F<.pm> and the
225 |  |  |  |  | (compiled) F<.xs> parts are compatible. If C<$VERSION> was specified, this
226 |  |  |  |  | is used for the check. If not specified, it defaults to
227 |  |  |  |  | C<$XS_VERSION // $VERSION> (in the module's namespace)
228 |  |  |  |  |
229 |  |  |  |  | =item *
230 |  |  |  |  |
231 |  |  |  |  | the XSUBs are made accessible from Perl
232 |  |  |  |  |
233 |  |  |  |  | =item *
234 |  |  |  |  |
235 |  |  |  |  | if a C<BOOT:> section was present in the F<.xs> file, the code there is called.
236 |  |  |  |  |
237 |  |  |  |  | =back
238 |  |  |  |  |
239 |  |  |  |  | Consequently, if the code in the F<.pm> file makes calls to these XSUBs, it is
240 |  |  |  |  | convenient to have XSUBs installed before the Perl code is defined; for
241 |  |  |  |  | example, this makes prototypes for XSUBs visible to this Perl code.
242 |  |  |  |  | Alternatively, if the C<BOOT:> section makes calls to Perl functions (or
243 |  |  |  |  | uses Perl variables) defined in the F<.pm> file, they must be defined prior to
244 |  |  |  |  | the call to C<XSLoader::load()> (or C<bootstrap()>).
245 |  |  |  |  |
246 |  |  |  |  | The first situation being much more frequent, it makes sense to rewrite the
247 |  |  |  |  | boilerplate as
248 |  |  |  |  |
249 |  |  |  |  | package YourPackage;
250 |  |  |  |  | use XSLoader;
251 |  |  |  |  | use vars qw($VERSION @ISA);
252 |  |  |  |  |
253 |  |  |  |  | BEGIN {
254 |  |  |  |  | @ISA = qw( OnePackage OtherPackage );
255 |  |  |  |  | $VERSION = '0.01';
256 |  |  |  |  |
257 |  |  |  |  | # Put Perl code used in the BOOT: section here
258 |  |  |  |  |
259 |  |  |  |  | XSLoader::load 'YourPackage', $VERSION;
260 |  |  |  |  | }
261 |  |  |  |  |
262 |  |  |  |  | # Put Perl code making calls into XSUBs here
263 |  |  |  |  |
264 |  |  |  |  | =head2 The most hairy case
265 |  |  |  |  |
266 |  |  |  |  | If the interdependence of your C<BOOT:> section and Perl code is
267 |  |  |  |  | more complicated than this (e.g., the C<BOOT:> section makes calls to Perl
268 |  |  |  |  | functions which make calls to XSUBs with prototypes), get rid of the C<BOOT:>
269 |  |  |  |  | section altogether. Replace it with a function C<onBOOT()>, and call it like
270 |  |  |  |  | this:
271 |  |  |  |  |
272 |  |  |  |  | package YourPackage;
273 |  |  |  |  | use XSLoader;
274 |  |  |  |  | use vars qw($VERSION @ISA);
275 |  |  |  |  |
276 |  |  |  |  | BEGIN {
277 |  |  |  |  | @ISA = qw( OnePackage OtherPackage );
278 |  |  |  |  | $VERSION = '0.01';
279 |  |  |  |  | XSLoader::load 'YourPackage', $VERSION;
280 |  |  |  |  | }
281 |  |  |  |  |
282 |  |  |  |  | # Put Perl code used in onBOOT() function here; calls to XSUBs are
283 |  |  |  |  | # prototype-checked.
284 |  |  |  |  |
285 |  |  |  |  | onBOOT;
286 |  |  |  |  |
287 |  |  |  |  | # Put Perl initialization code assuming that XS is initialized here
288 |  |  |  |  |
289 |  |  |  |  |
290 |  |  |  |  | =head1 DIAGNOSTICS
291 |  |  |  |  |
292 |  |  |  |  | =over
293 |  |  |  |  |
294 |  |  |  |  | =item C<Can't find '%s' symbol in %s>
295 |  |  |  |  |
296 |  |  |  |  | B<(F)> The bootstrap symbol could not be found in the extension module.
297 |  |  |  |  |
298 |  |  |  |  | =item C<Can't load '%s' for module %s: %s>
299 |  |  |  |  |
300 |  |  |  |  | B<(F)> The loading or initialisation of the extension module failed.
301 |  |  |  |  | The detailed error follows.
302 |  |  |  |  |
303 |  |  |  |  | =item C<Undefined symbols present after loading %s: %s>
304 |  |  |  |  |
305 |  |  |  |  | B<(W)> As the message says, some symbols stay undefined although the
306 |  |  |  |  | extension module was correctly loaded and initialised. The list of undefined
307 |  |  |  |  | symbols follows.
308 |  |  |  |  |
309 |  |  |  |  | =back
310 |  |  |  |  |
311 |  |  |  |  | =head1 LIMITATIONS
312 |  |  |  |  |
313 |  |  |  |  | To reduce the overhead as much as possible, only one possible location
314 |  |  |  |  | is checked to find the extension DLL (this location is where C<make install>
315 |  |  |  |  | would put the DLL). If not found, the search for the DLL is transparently
316 |  |  |  |  | delegated to C<DynaLoader>, which looks for the DLL along the C<@INC> list.
317 |  |  |  |  |
318 |  |  |  |  | In particular, this is applicable to the structure of C<@INC> used for testing
319 |  |  |  |  | not-yet-installed extensions. This means that running uninstalled extensions
320 |  |  |  |  | may have much more overhead than running the same extensions after
321 |  |  |  |  | C<make install>.
322 |  |  |  |  |
323 |  |  |  |  |
324 |  |  |  |  | =head1 KNOWN BUGS
325 |  |  |  |  |
326 |  |  |  |  | The new simpler way to call C<XSLoader::load()> with no arguments at all
327 |  |  |  |  | does not work on Perl 5.8.4 and 5.8.5.
328 |  |  |  |  |
329 |  |  |  |  |
330 |  |  |  |  | =head1 BUGS
331 |  |  |  |  |
332 |  |  |  |  | Please report any bugs or feature requests via the perlbug(1) utility.
333 |  |  |  |  |
334 |  |  |  |  |
335 |  |  |  |  | =head1 SEE ALSO
336 |  |  |  |  |
337 |  |  |  |  | L<DynaLoader>
338 |  |  |  |  |
339 |  |  |  |  |
340 |  |  |  |  | =head1 AUTHORS
341 |  |  |  |  |
342 |  |  |  |  | Ilya Zakharevich originally extracted C<XSLoader> from C<DynaLoader>.
343 |  |  |  |  |
344 |  |  |  |  | CPAN version is currently maintained by SE<eacute>bastien Aperghis-Tramoni
345 |  |  |  |  | E<lt>sebastien@aperghis.netE<gt>.
346 |  |  |  |  |
347 |  |  |  |  | Previous maintainer was Michael G Schwern <schwern@pobox.com>.
348 |  |  |  |  |
349 |  |  |  |  |
350 |  |  |  |  | =head1 COPYRIGHT & LICENSE
351 |  |  |  |  |
352 |  |  |  |  | Copyright (C) 1990-2011 by Larry Wall and others.
353 |  |  |  |  |
354 |  |  |  |  | This program is free software; you can redistribute it and/or modify
355 |  |  |  |  | it under the same terms as Perl itself.
356 |  |  |  |  |
357 |  |  |  |  | =cut