Filename | /usr/lib/perl5/5.14/XSLoader.pm |
Statements | Executed 0 statements in 14µs |
Calls | P | F | Exclusive Time |
Inclusive Time |
Subroutine |
---|---|---|---|---|---|
8 | 8 | 8 | 9.89ms | 9.89ms | load | XSLoader::
0 | 0 | 0 | 0s | 0s | bootstrap_inherit | XSLoader::
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 = "0.13"; | ||||
6 | |||||
7 | #use strict; | ||||
8 | |||||
9 | # enable debug/trace messages from DynaLoader perl code | ||||
10 | # $dl_debug = $ENV{PERL_DL_DEBUG} || 0 unless defined $dl_debug; | ||||
11 | |||||
12 | package DynaLoader; | ||||
13 | |||||
14 | # No prizes for guessing why we don't say 'bootstrap DynaLoader;' here. | ||||
15 | # NOTE: All dl_*.xs (including dl_none.xs) define a dl_error() XSUB | ||||
16 | boot_DynaLoader('DynaLoader') if defined(&boot_DynaLoader) && | ||||
17 | !defined(&dl_error); | ||||
18 | package XSLoader; | ||||
19 | |||||
20 | # spent 9.89ms within XSLoader::load which was called 8 times, avg 1.24ms/call:
# once (1.77ms+0s) by installer::epmfile::BEGIN@42 at line 36 of POSIX.pm
# once (1.62ms+0s) by Archive::Zip::BEGIN@12 at line 92 of Compress/Raw/Zlib.pm
# once (1.27ms+0s) by installer::BEGIN@33 at line 36 of Data/Dumper.pm
# once (1.23ms+0s) by installer::windows::file::BEGIN@30 at line 24 of Digest/MD5.pm
# once (1.18ms+0s) by IO::Handle::BEGIN@266 at line 11 of IO.pm
# once (1.17ms+0s) by IO::Seekable::BEGIN@104 at line 66 of Fcntl.pm
# once (1.03ms+0s) by installer::BEGIN@34 at line 27 of List/Util.pm
# once (633µs+0s) by installer::BEGIN@32 at line 248 of Cwd.pm | ||||
21 | package DynaLoader; | ||||
22 | |||||
23 | my ($module, $modlibname) = caller(); | ||||
24 | |||||
25 | if (@_) { | ||||
26 | $module = $_[0]; | ||||
27 | } else { | ||||
28 | $_[0] = $module; | ||||
29 | } | ||||
30 | |||||
31 | # work with static linking too | ||||
32 | my $boots = "$module\::bootstrap"; | ||||
33 | goto &$boots if defined &$boots; | ||||
34 | |||||
35 | goto \&XSLoader::bootstrap_inherit unless $module and defined &dl_load_file; | ||||
36 | |||||
37 | my @modparts = split(/::/,$module); | ||||
38 | my $modfname = $modparts[-1]; | ||||
39 | |||||
40 | my $modpname = join('/',@modparts); | ||||
41 | my $c = @modparts; | ||||
42 | $modlibname =~ s,[\\/][^\\/]+$,, while $c--; # Q&D basename | ||||
43 | my $file = "$modlibname/auto/$modpname/$modfname.dll"; | ||||
44 | |||||
45 | # print STDERR "XSLoader::load for $module ($file)\n" if $dl_debug; | ||||
46 | |||||
47 | my $bs = $file; | ||||
48 | $bs =~ s/(\.\w+)?(;\d*)?$/\.bs/; # look for .bs 'beside' the library | ||||
49 | |||||
50 | if (-s $bs) { # only read file if it's not empty | ||||
51 | # print STDERR "BS: $bs ($^O, $dlsrc)\n" if $dl_debug; | ||||
52 | eval { do $bs; }; | ||||
53 | warn "$bs: $@\n" if $@; | ||||
54 | } | ||||
55 | |||||
56 | goto \&XSLoader::bootstrap_inherit if not -f $file or -s $bs; | ||||
57 | |||||
58 | my $bootname = "boot_$module"; | ||||
59 | $bootname =~ s/\W/_/g; | ||||
60 | @DynaLoader::dl_require_symbols = ($bootname); | ||||
61 | |||||
62 | my $boot_symbol_ref; | ||||
63 | |||||
64 | # Many dynamic extension loading problems will appear to come from | ||||
65 | # this section of code: XYZ failed at line 123 of DynaLoader.pm. | ||||
66 | # Often these errors are actually occurring in the initialisation | ||||
67 | # C code of the extension XS file. Perl reports the error as being | ||||
68 | # in this perl code simply because this was the last perl code | ||||
69 | # it executed. | ||||
70 | |||||
71 | my $libref = dl_load_file($file, 0) or do { | ||||
72 | require Carp; | ||||
73 | Carp::croak("Can't load '$file' for module $module: " . dl_error()); | ||||
74 | }; | ||||
75 | push(@DynaLoader::dl_librefs,$libref); # record loaded object | ||||
76 | |||||
77 | my @unresolved = dl_undef_symbols(); | ||||
78 | if (@unresolved) { | ||||
79 | require Carp; | ||||
80 | Carp::carp("Undefined symbols present after loading $file: @unresolved\n"); | ||||
81 | } | ||||
82 | |||||
83 | $boot_symbol_ref = dl_find_symbol($libref, $bootname) or do { | ||||
84 | require Carp; | ||||
85 | Carp::croak("Can't find '$bootname' symbol in $file\n"); | ||||
86 | }; | ||||
87 | |||||
88 | push(@DynaLoader::dl_modules, $module); # record loaded module | ||||
89 | |||||
90 | boot: | ||||
91 | my $xs = dl_install_xsub($boots, $boot_symbol_ref, $file); | ||||
92 | |||||
93 | # See comment block above | ||||
94 | push(@DynaLoader::dl_shared_objects, $file); # record files loaded | ||||
95 | return &$xs(@_); | ||||
96 | } | ||||
97 | |||||
98 | sub bootstrap_inherit { | ||||
99 | 1 | 14µs | require DynaLoader; | ||
100 | goto \&DynaLoader::bootstrap_inherit; | ||||
101 | } | ||||
102 | |||||
103 | 1; | ||||
104 | |||||
105 | |||||
106 | __END__ | ||||
107 | |||||
108 | =head1 NAME | ||||
109 | |||||
110 | XSLoader - Dynamically load C libraries into Perl code | ||||
111 | |||||
112 | =head1 VERSION | ||||
113 | |||||
114 | Version 0.13 | ||||
115 | |||||
116 | =head1 SYNOPSIS | ||||
117 | |||||
118 | package YourPackage; | ||||
119 | require XSLoader; | ||||
120 | |||||
121 | XSLoader::load(); | ||||
122 | |||||
123 | =head1 DESCRIPTION | ||||
124 | |||||
125 | This module defines a standard I<simplified> interface to the dynamic | ||||
126 | linking mechanisms available on many platforms. Its primary purpose is | ||||
127 | to implement cheap automatic dynamic loading of Perl modules. | ||||
128 | |||||
129 | For a more complicated interface, see L<DynaLoader>. Many (most) | ||||
130 | features of C<DynaLoader> are not implemented in C<XSLoader>, like for | ||||
131 | example the C<dl_load_flags>, not honored by C<XSLoader>. | ||||
132 | |||||
133 | =head2 Migration from C<DynaLoader> | ||||
134 | |||||
135 | A typical module using L<DynaLoader|DynaLoader> starts like this: | ||||
136 | |||||
137 | package YourPackage; | ||||
138 | require DynaLoader; | ||||
139 | |||||
140 | our @ISA = qw( OnePackage OtherPackage DynaLoader ); | ||||
141 | our $VERSION = '0.01'; | ||||
142 | bootstrap YourPackage $VERSION; | ||||
143 | |||||
144 | Change this to | ||||
145 | |||||
146 | package YourPackage; | ||||
147 | use XSLoader; | ||||
148 | |||||
149 | our @ISA = qw( OnePackage OtherPackage ); | ||||
150 | our $VERSION = '0.01'; | ||||
151 | XSLoader::load 'YourPackage', $VERSION; | ||||
152 | |||||
153 | In other words: replace C<require DynaLoader> by C<use XSLoader>, remove | ||||
154 | C<DynaLoader> from C<@ISA>, change C<bootstrap> by C<XSLoader::load>. Do not | ||||
155 | forget to quote the name of your package on the C<XSLoader::load> line, | ||||
156 | and add comma (C<,>) before the arguments (C<$VERSION> above). | ||||
157 | |||||
158 | Of course, if C<@ISA> contained only C<DynaLoader>, there is no need to have | ||||
159 | the C<@ISA> assignment at all; moreover, if instead of C<our> one uses the | ||||
160 | more backward-compatible | ||||
161 | |||||
162 | use vars qw($VERSION @ISA); | ||||
163 | |||||
164 | one can remove this reference to C<@ISA> together with the C<@ISA> assignment. | ||||
165 | |||||
166 | If no C<$VERSION> was specified on the C<bootstrap> line, the last line becomes | ||||
167 | |||||
168 | XSLoader::load 'YourPackage'; | ||||
169 | |||||
170 | If the call to C<load> is from the YourPackage, then that can be further | ||||
171 | simplified to | ||||
172 | |||||
173 | XSLoader::load(); | ||||
174 | |||||
175 | as C<load> will use C<caller> to determine the package. | ||||
176 | |||||
177 | =head2 Backward compatible boilerplate | ||||
178 | |||||
179 | If you want to have your cake and eat it too, you need a more complicated | ||||
180 | boilerplate. | ||||
181 | |||||
182 | package YourPackage; | ||||
183 | use vars qw($VERSION @ISA); | ||||
184 | |||||
185 | @ISA = qw( OnePackage OtherPackage ); | ||||
186 | $VERSION = '0.01'; | ||||
187 | eval { | ||||
188 | require XSLoader; | ||||
189 | XSLoader::load('YourPackage', $VERSION); | ||||
190 | 1; | ||||
191 | } or do { | ||||
192 | require DynaLoader; | ||||
193 | push @ISA, 'DynaLoader'; | ||||
194 | bootstrap YourPackage $VERSION; | ||||
195 | }; | ||||
196 | |||||
197 | The parentheses about C<XSLoader::load()> arguments are needed since we replaced | ||||
198 | C<use XSLoader> by C<require>, so the compiler does not know that a function | ||||
199 | C<XSLoader::load()> is present. | ||||
200 | |||||
201 | This boilerplate uses the low-overhead C<XSLoader> if present; if used with | ||||
202 | an antic Perl which has no C<XSLoader>, it falls back to using C<DynaLoader>. | ||||
203 | |||||
204 | =head1 Order of initialization: early load() | ||||
205 | |||||
206 | I<Skip this section if the XSUB functions are supposed to be called from other | ||||
207 | modules only; read it only if you call your XSUBs from the code in your module, | ||||
208 | or have a C<BOOT:> section in your XS file (see L<perlxs/"The BOOT: Keyword">). | ||||
209 | What is described here is equally applicable to the L<DynaLoader|DynaLoader> | ||||
210 | interface.> | ||||
211 | |||||
212 | A sufficiently complicated module using XS would have both Perl code (defined | ||||
213 | in F<YourPackage.pm>) and XS code (defined in F<YourPackage.xs>). If this | ||||
214 | Perl code makes calls into this XS code, and/or this XS code makes calls to | ||||
215 | the Perl code, one should be careful with the order of initialization. | ||||
216 | |||||
217 | The call to C<XSLoader::load()> (or C<bootstrap()>) calls the module's | ||||
218 | bootstrap code. For modules build by F<xsubpp> (nearly all modules) this | ||||
219 | has three side effects: | ||||
220 | |||||
221 | =over | ||||
222 | |||||
223 | =item * | ||||
224 | |||||
225 | A sanity check is done to ensure that the versions of the F<.pm> and the | ||||
226 | (compiled) F<.xs> parts are compatible. If C<$VERSION> was specified, this | ||||
227 | is used for the check. If not specified, it defaults to | ||||
228 | C<$XS_VERSION // $VERSION> (in the module's namespace) | ||||
229 | |||||
230 | =item * | ||||
231 | |||||
232 | the XSUBs are made accessible from Perl | ||||
233 | |||||
234 | =item * | ||||
235 | |||||
236 | if a C<BOOT:> section was present in the F<.xs> file, the code there is called. | ||||
237 | |||||
238 | =back | ||||
239 | |||||
240 | Consequently, if the code in the F<.pm> file makes calls to these XSUBs, it is | ||||
241 | convenient to have XSUBs installed before the Perl code is defined; for | ||||
242 | example, this makes prototypes for XSUBs visible to this Perl code. | ||||
243 | Alternatively, if the C<BOOT:> section makes calls to Perl functions (or | ||||
244 | uses Perl variables) defined in the F<.pm> file, they must be defined prior to | ||||
245 | the call to C<XSLoader::load()> (or C<bootstrap()>). | ||||
246 | |||||
247 | The first situation being much more frequent, it makes sense to rewrite the | ||||
248 | boilerplate as | ||||
249 | |||||
250 | package YourPackage; | ||||
251 | use XSLoader; | ||||
252 | use vars qw($VERSION @ISA); | ||||
253 | |||||
254 | BEGIN { | ||||
255 | @ISA = qw( OnePackage OtherPackage ); | ||||
256 | $VERSION = '0.01'; | ||||
257 | |||||
258 | # Put Perl code used in the BOOT: section here | ||||
259 | |||||
260 | XSLoader::load 'YourPackage', $VERSION; | ||||
261 | } | ||||
262 | |||||
263 | # Put Perl code making calls into XSUBs here | ||||
264 | |||||
265 | =head2 The most hairy case | ||||
266 | |||||
267 | If the interdependence of your C<BOOT:> section and Perl code is | ||||
268 | more complicated than this (e.g., the C<BOOT:> section makes calls to Perl | ||||
269 | functions which make calls to XSUBs with prototypes), get rid of the C<BOOT:> | ||||
270 | section altogether. Replace it with a function C<onBOOT()>, and call it like | ||||
271 | this: | ||||
272 | |||||
273 | package YourPackage; | ||||
274 | use XSLoader; | ||||
275 | use vars qw($VERSION @ISA); | ||||
276 | |||||
277 | BEGIN { | ||||
278 | @ISA = qw( OnePackage OtherPackage ); | ||||
279 | $VERSION = '0.01'; | ||||
280 | XSLoader::load 'YourPackage', $VERSION; | ||||
281 | } | ||||
282 | |||||
283 | # Put Perl code used in onBOOT() function here; calls to XSUBs are | ||||
284 | # prototype-checked. | ||||
285 | |||||
286 | onBOOT; | ||||
287 | |||||
288 | # Put Perl initialization code assuming that XS is initialized here | ||||
289 | |||||
290 | |||||
291 | =head1 DIAGNOSTICS | ||||
292 | |||||
293 | =over | ||||
294 | |||||
295 | =item C<Can't find '%s' symbol in %s> | ||||
296 | |||||
297 | B<(F)> The bootstrap symbol could not be found in the extension module. | ||||
298 | |||||
299 | =item C<Can't load '%s' for module %s: %s> | ||||
300 | |||||
301 | B<(F)> The loading or initialisation of the extension module failed. | ||||
302 | The detailed error follows. | ||||
303 | |||||
304 | =item C<Undefined symbols present after loading %s: %s> | ||||
305 | |||||
306 | B<(W)> As the message says, some symbols stay undefined although the | ||||
307 | extension module was correctly loaded and initialised. The list of undefined | ||||
308 | symbols follows. | ||||
309 | |||||
310 | =back | ||||
311 | |||||
312 | =head1 LIMITATIONS | ||||
313 | |||||
314 | To reduce the overhead as much as possible, only one possible location | ||||
315 | is checked to find the extension DLL (this location is where C<make install> | ||||
316 | would put the DLL). If not found, the search for the DLL is transparently | ||||
317 | delegated to C<DynaLoader>, which looks for the DLL along the C<@INC> list. | ||||
318 | |||||
319 | In particular, this is applicable to the structure of C<@INC> used for testing | ||||
320 | not-yet-installed extensions. This means that running uninstalled extensions | ||||
321 | may have much more overhead than running the same extensions after | ||||
322 | C<make install>. | ||||
323 | |||||
324 | |||||
325 | =head1 BUGS | ||||
326 | |||||
327 | Please report any bugs or feature requests via the perlbug(1) utility. | ||||
328 | |||||
329 | |||||
330 | =head1 SEE ALSO | ||||
331 | |||||
332 | L<DynaLoader> | ||||
333 | |||||
334 | |||||
335 | =head1 AUTHORS | ||||
336 | |||||
337 | Ilya Zakharevich originally extracted C<XSLoader> from C<DynaLoader>. | ||||
338 | |||||
339 | CPAN version is currently maintained by SE<eacute>bastien Aperghis-Tramoni | ||||
340 | E<lt>sebastien@aperghis.netE<gt>. | ||||
341 | |||||
342 | Previous maintainer was Michael G Schwern <schwern@pobox.com>. | ||||
343 | |||||
344 | |||||
345 | =head1 COPYRIGHT & LICENSE | ||||
346 | |||||
347 | Copyright (C) 1990-2007 by Larry Wall and others. | ||||
348 | |||||
349 | This program is free software; you can redistribute it and/or modify | ||||
350 | it under the same terms as Perl itself. | ||||
351 | |||||
352 | =cut |