Commit | Line | Data |
11fd7d05 |
1 | use strict; |
9cf41c4d |
2 | use Config; |
3 | |
4 | sub to_string { |
5 | my ($value) = @_; |
6 | $value =~ s/\\/\\\\/g; |
7 | $value =~ s/'/\\'/g; |
8 | return "'$value'"; |
9 | } |
10 | |
11fd7d05 |
11 | 1 while unlink "XSLoader.pm"; |
9cf41c4d |
12 | open OUT, ">XSLoader.pm" or die $!; |
13 | print OUT <<'EOT'; |
14 | # Generated from XSLoader.pm.PL (resolved %Config::Config value) |
15 | |
16 | package XSLoader; |
17 | |
b0d07b4e |
18 | $VERSION = "0.08"; |
11fd7d05 |
19 | |
20 | #use strict; |
9cf41c4d |
21 | |
22 | # enable debug/trace messages from DynaLoader perl code |
23 | # $dl_debug = $ENV{PERL_DL_DEBUG} || 0 unless defined $dl_debug; |
24 | |
25 | EOT |
26 | |
27 | print OUT ' my $dl_dlext = ', to_string($Config::Config{'dlext'}), ";\n" ; |
28 | |
29 | print OUT <<'EOT'; |
30 | |
9cf41c4d |
31 | package DynaLoader; |
b4cea227 |
32 | |
33 | # No prizes for guessing why we don't say 'bootstrap DynaLoader;' here. |
34 | # NOTE: All dl_*.xs (including dl_none.xs) define a dl_error() XSUB |
9cf41c4d |
35 | boot_DynaLoader('DynaLoader') if defined(&boot_DynaLoader) && |
b4cea227 |
36 | !defined(&dl_error); |
9cf41c4d |
37 | package XSLoader; |
38 | |
9cf41c4d |
39 | sub load { |
40 | package DynaLoader; |
41 | |
9e8c31cc |
42 | die q{XSLoader::load('Your::Module', $Your::Module::VERSION)} unless @_; |
43 | |
9cf41c4d |
44 | my($module) = $_[0]; |
45 | |
46 | # work with static linking too |
47 | my $b = "$module\::bootstrap"; |
48 | goto &$b if defined &$b; |
49 | |
50 | goto retry unless $module and defined &dl_load_file; |
51 | |
52 | my @modparts = split(/::/,$module); |
53 | my $modfname = $modparts[-1]; |
54 | |
55 | EOT |
56 | |
57 | print OUT <<'EOT' if defined &DynaLoader::mod2fname; |
58 | # Some systems have restrictions on files names for DLL's etc. |
59 | # mod2fname returns appropriate file base name (typically truncated) |
60 | # It may also edit @modparts if required. |
61 | $modfname = &mod2fname(\@modparts) if defined &mod2fname; |
62 | |
63 | EOT |
64 | |
9d419b5f |
65 | print OUT <<'EOT' if $^O eq 'os2'; |
66 | |
67 | # os2 static build can dynaload, but cannot dynaload Perl modules... |
68 | die 'Dynaloaded Perl modules are not available in this build of Perl' if $OS2::is_static; |
69 | |
70 | EOT |
b0d07b4e |
71 | |
9cf41c4d |
72 | print OUT <<'EOT'; |
73 | my $modpname = join('/',@modparts); |
74 | my $modlibname = (caller())[1]; |
75 | my $c = @modparts; |
76 | $modlibname =~ s,[\\/][^\\/]+$,, while $c--; # Q&D basename |
77 | my $file = "$modlibname/auto/$modpname/$modfname.$dl_dlext"; |
78 | |
79 | # print STDERR "XSLoader::load for $module ($file)\n" if $dl_debug; |
80 | |
81 | my $bs = $file; |
82 | $bs =~ s/(\.\w+)?(;\d*)?$/\.bs/; # look for .bs 'beside' the library |
83 | |
84 | goto retry if not -f $file or -s $bs; |
85 | |
86 | my $bootname = "boot_$module"; |
87 | $bootname =~ s/\W/_/g; |
11fd7d05 |
88 | @DynaLoader::dl_require_symbols = ($bootname); |
9cf41c4d |
89 | |
588cafc8 |
90 | my $boot_symbol_ref; |
91 | |
68d3ba50 |
92 | EOT |
93 | |
588cafc8 |
94 | if ($^O eq 'darwin') { |
68d3ba50 |
95 | print OUT <<'EOT'; |
588cafc8 |
96 | if ($boot_symbol_ref = dl_find_symbol(0, $bootname)) { |
97 | goto boot; #extension library has already been loaded, e.g. darwin |
98 | } |
68d3ba50 |
99 | EOT |
588cafc8 |
100 | } |
101 | |
68d3ba50 |
102 | print OUT <<'EOT'; |
9cf41c4d |
103 | # Many dynamic extension loading problems will appear to come from |
104 | # this section of code: XYZ failed at line 123 of DynaLoader.pm. |
105 | # Often these errors are actually occurring in the initialisation |
106 | # C code of the extension XS file. Perl reports the error as being |
107 | # in this perl code simply because this was the last perl code |
108 | # it executed. |
109 | |
110 | my $libref = dl_load_file($file, 0) or do { |
11fd7d05 |
111 | require Carp; |
112 | Carp::croak("Can't load '$file' for module $module: " . dl_error()); |
9cf41c4d |
113 | }; |
11fd7d05 |
114 | push(@DynaLoader::dl_librefs,$libref); # record loaded object |
9cf41c4d |
115 | |
116 | my @unresolved = dl_undef_symbols(); |
117 | if (@unresolved) { |
11fd7d05 |
118 | require Carp; |
119 | Carp::carp("Undefined symbols present after loading $file: @unresolved\n"); |
9cf41c4d |
120 | } |
121 | |
588cafc8 |
122 | $boot_symbol_ref = dl_find_symbol($libref, $bootname) or do { |
11fd7d05 |
123 | require Carp; |
124 | Carp::croak("Can't find '$bootname' symbol in $file\n"); |
9cf41c4d |
125 | }; |
126 | |
11fd7d05 |
127 | push(@DynaLoader::dl_modules, $module); # record loaded module |
9cf41c4d |
128 | |
588cafc8 |
129 | boot: |
130 | my $xs = dl_install_xsub("${module}::bootstrap", $boot_symbol_ref, $file); |
131 | |
9cf41c4d |
132 | # See comment block above |
89166d32 |
133 | push(@DynaLoader::dl_shared_objects, $file); # record files loaded |
9cf41c4d |
134 | return &$xs(@_); |
135 | |
136 | retry: |
11fd7d05 |
137 | my $bootstrap_inherit = DynaLoader->can('bootstrap_inherit') || |
138 | XSLoader->can('bootstrap_inherit'); |
139 | goto &$bootstrap_inherit; |
140 | } |
141 | |
142 | # Versions of DynaLoader prior to 5.6.0 don't have this function. |
143 | sub bootstrap_inherit { |
144 | package DynaLoader; |
145 | |
146 | my $module = $_[0]; |
147 | local *DynaLoader::isa = *{"$module\::ISA"}; |
148 | local @DynaLoader::isa = (@DynaLoader::isa, 'DynaLoader'); |
149 | # Cannot goto due to delocalization. Will report errors on a wrong line? |
9cf41c4d |
150 | require DynaLoader; |
11fd7d05 |
151 | DynaLoader::bootstrap(@_); |
9cf41c4d |
152 | } |
153 | |
9e8c31cc |
154 | 1; |
155 | |
11fd7d05 |
156 | |
9cf41c4d |
157 | __END__ |
158 | |
159 | =head1 NAME |
160 | |
161 | XSLoader - Dynamically load C libraries into Perl code |
162 | |
11fd7d05 |
163 | =head1 VERSION |
164 | |
b0d07b4e |
165 | Version 0.08 |
11fd7d05 |
166 | |
9cf41c4d |
167 | =head1 SYNOPSIS |
168 | |
169 | package YourPackage; |
170 | use XSLoader; |
171 | |
9e8c31cc |
172 | XSLoader::load 'YourPackage', $YourPackage::VERSION; |
9cf41c4d |
173 | |
174 | =head1 DESCRIPTION |
175 | |
176 | This module defines a standard I<simplified> interface to the dynamic |
177 | linking mechanisms available on many platforms. Its primary purpose is |
178 | to implement cheap automatic dynamic loading of Perl modules. |
179 | |
4406dda9 |
180 | For a more complicated interface, see L<DynaLoader>. Many (most) |
11fd7d05 |
181 | features of C<DynaLoader> are not implemented in C<XSLoader>, like for |
182 | example the C<dl_load_flags>, not honored by C<XSLoader>. |
9cf41c4d |
183 | |
d7f44de2 |
184 | =head2 Migration from C<DynaLoader> |
185 | |
186 | A typical module using L<DynaLoader|DynaLoader> starts like this: |
187 | |
188 | package YourPackage; |
189 | require DynaLoader; |
190 | |
191 | our @ISA = qw( OnePackage OtherPackage DynaLoader ); |
192 | our $VERSION = '0.01'; |
193 | bootstrap YourPackage $VERSION; |
194 | |
195 | Change this to |
196 | |
197 | package YourPackage; |
198 | use XSLoader; |
199 | |
200 | our @ISA = qw( OnePackage OtherPackage ); |
201 | our $VERSION = '0.01'; |
202 | XSLoader::load 'YourPackage', $VERSION; |
203 | |
204 | In other words: replace C<require DynaLoader> by C<use XSLoader>, remove |
11fd7d05 |
205 | C<DynaLoader> from C<@ISA>, change C<bootstrap> by C<XSLoader::load>. Do not |
d7f44de2 |
206 | forget to quote the name of your package on the C<XSLoader::load> line, |
9c6b46e2 |
207 | and add comma (C<,>) before the arguments (C<$VERSION> above). |
d7f44de2 |
208 | |
11fd7d05 |
209 | Of course, if C<@ISA> contained only C<DynaLoader>, there is no need to have |
210 | the C<@ISA> assignment at all; moreover, if instead of C<our> one uses the |
211 | more backward-compatible |
d7f44de2 |
212 | |
213 | use vars qw($VERSION @ISA); |
214 | |
11fd7d05 |
215 | one can remove this reference to C<@ISA> together with the C<@ISA> assignment. |
d7f44de2 |
216 | |
11fd7d05 |
217 | If no C<$VERSION> was specified on the C<bootstrap> line, the last line becomes |
d7f44de2 |
218 | |
219 | XSLoader::load 'YourPackage'; |
220 | |
221 | =head2 Backward compatible boilerplate |
222 | |
223 | If you want to have your cake and eat it too, you need a more complicated |
224 | boilerplate. |
225 | |
226 | package YourPackage; |
227 | use vars qw($VERSION @ISA); |
228 | |
229 | @ISA = qw( OnePackage OtherPackage ); |
230 | $VERSION = '0.01'; |
231 | eval { |
232 | require XSLoader; |
233 | XSLoader::load('YourPackage', $VERSION); |
234 | 1; |
235 | } or do { |
236 | require DynaLoader; |
237 | push @ISA, 'DynaLoader'; |
238 | bootstrap YourPackage $VERSION; |
239 | }; |
240 | |
11fd7d05 |
241 | The parentheses about C<XSLoader::load()> arguments are needed since we replaced |
d7f44de2 |
242 | C<use XSLoader> by C<require>, so the compiler does not know that a function |
11fd7d05 |
243 | C<XSLoader::load()> is present. |
d7f44de2 |
244 | |
245 | This boilerplate uses the low-overhead C<XSLoader> if present; if used with |
246 | an antic Perl which has no C<XSLoader>, it falls back to using C<DynaLoader>. |
247 | |
248 | =head1 Order of initialization: early load() |
249 | |
250 | I<Skip this section if the XSUB functions are supposed to be called from other |
251 | modules only; read it only if you call your XSUBs from the code in your module, |
252 | or have a C<BOOT:> section in your XS file (see L<perlxs/"The BOOT: Keyword">). |
4406dda9 |
253 | What is described here is equally applicable to the L<DynaLoader|DynaLoader> |
d7f44de2 |
254 | interface.> |
255 | |
256 | A sufficiently complicated module using XS would have both Perl code (defined |
257 | in F<YourPackage.pm>) and XS code (defined in F<YourPackage.xs>). If this |
258 | Perl code makes calls into this XS code, and/or this XS code makes calls to |
259 | the Perl code, one should be careful with the order of initialization. |
260 | |
11fd7d05 |
261 | The call to C<XSLoader::load()> (or C<bootstrap()>) has three side effects: |
d7f44de2 |
262 | |
263 | =over |
264 | |
265 | =item * |
266 | |
11fd7d05 |
267 | if C<$VERSION> was specified, a sanity check is done to ensure that the |
268 | versions of the F<.pm> and the (compiled) F<.xs> parts are compatible; |
d7f44de2 |
269 | |
270 | =item * |
271 | |
4406dda9 |
272 | the XSUBs are made accessible from Perl; |
d7f44de2 |
273 | |
274 | =item * |
275 | |
4406dda9 |
276 | if a C<BOOT:> section was present in the F<.xs> file, the code there is called. |
d7f44de2 |
277 | |
278 | =back |
279 | |
4406dda9 |
280 | Consequently, if the code in the F<.pm> file makes calls to these XSUBs, it is |
d7f44de2 |
281 | convenient to have XSUBs installed before the Perl code is defined; for |
282 | example, this makes prototypes for XSUBs visible to this Perl code. |
283 | Alternatively, if the C<BOOT:> section makes calls to Perl functions (or |
4406dda9 |
284 | uses Perl variables) defined in the F<.pm> file, they must be defined prior to |
11fd7d05 |
285 | the call to C<XSLoader::load()> (or C<bootstrap()>). |
d7f44de2 |
286 | |
287 | The first situation being much more frequent, it makes sense to rewrite the |
288 | boilerplate as |
289 | |
290 | package YourPackage; |
291 | use XSLoader; |
292 | use vars qw($VERSION @ISA); |
293 | |
294 | BEGIN { |
295 | @ISA = qw( OnePackage OtherPackage ); |
296 | $VERSION = '0.01'; |
297 | |
298 | # Put Perl code used in the BOOT: section here |
299 | |
300 | XSLoader::load 'YourPackage', $VERSION; |
301 | } |
302 | |
303 | # Put Perl code making calls into XSUBs here |
304 | |
305 | =head2 The most hairy case |
306 | |
307 | If the interdependence of your C<BOOT:> section and Perl code is |
308 | more complicated than this (e.g., the C<BOOT:> section makes calls to Perl |
309 | functions which make calls to XSUBs with prototypes), get rid of the C<BOOT:> |
11fd7d05 |
310 | section altogether. Replace it with a function C<onBOOT()>, and call it like |
d7f44de2 |
311 | this: |
312 | |
313 | package YourPackage; |
314 | use XSLoader; |
315 | use vars qw($VERSION @ISA); |
316 | |
317 | BEGIN { |
318 | @ISA = qw( OnePackage OtherPackage ); |
319 | $VERSION = '0.01'; |
320 | XSLoader::load 'YourPackage', $VERSION; |
321 | } |
322 | |
323 | # Put Perl code used in onBOOT() function here; calls to XSUBs are |
324 | # prototype-checked. |
325 | |
326 | onBOOT; |
327 | |
328 | # Put Perl initialization code assuming that XS is initialized here |
329 | |
11fd7d05 |
330 | |
331 | =head1 DIAGNOSTICS |
332 | |
150e77ce |
333 | =over |
11fd7d05 |
334 | |
150e77ce |
335 | =item C<Can't find '%s' symbol in %s> |
11fd7d05 |
336 | |
337 | B<(F)> The bootstrap symbol could not be found in the extension module. |
338 | |
150e77ce |
339 | =item C<Can't load '%s' for module %s: %s> |
11fd7d05 |
340 | |
341 | B<(F)> The loading or initialisation of the extension module failed. |
342 | The detailed error follows. |
343 | |
150e77ce |
344 | =item C<Undefined symbols present after loading %s: %s> |
11fd7d05 |
345 | |
346 | B<(W)> As the message says, some symbols stay undefined although the |
347 | extension module was correctly loaded and initialised. The list of undefined |
348 | symbols follows. |
349 | |
150e77ce |
350 | =item C<XSLoader::load('Your::Module', $Your::Module::VERSION)> |
11fd7d05 |
351 | |
352 | B<(F)> You tried to invoke C<load()> without any argument. You must supply |
353 | a module name, and optionally its version. |
354 | |
355 | =back |
356 | |
357 | |
d7f44de2 |
358 | =head1 LIMITATIONS |
359 | |
360 | To reduce the overhead as much as possible, only one possible location |
361 | is checked to find the extension DLL (this location is where C<make install> |
362 | would put the DLL). If not found, the search for the DLL is transparently |
11fd7d05 |
363 | delegated to C<DynaLoader>, which looks for the DLL along the C<@INC> list. |
d7f44de2 |
364 | |
11fd7d05 |
365 | In particular, this is applicable to the structure of C<@INC> used for testing |
4406dda9 |
366 | not-yet-installed extensions. This means that running uninstalled extensions |
367 | may have much more overhead than running the same extensions after |
d7f44de2 |
368 | C<make install>. |
369 | |
11fd7d05 |
370 | |
371 | =head1 BUGS |
372 | |
9c6b46e2 |
373 | Please report any bugs or feature requests via the perlbug(1) utility. |
11fd7d05 |
374 | |
375 | |
376 | =head1 SEE ALSO |
377 | |
378 | L<DynaLoader> |
379 | |
380 | |
9c6b46e2 |
381 | =head1 AUTHORS |
9cf41c4d |
382 | |
11fd7d05 |
383 | Ilya Zakharevich originally extracted C<XSLoader> from C<DynaLoader>. |
384 | |
385 | CPAN version is currently maintained by SE<eacute>bastien Aperghis-Tramoni |
150e77ce |
386 | E<lt>sebastien@aperghis.netE<gt>. |
11fd7d05 |
387 | |
150e77ce |
388 | Previous maintainer was Michael G Schwern <schwern@pobox.com>. |
11fd7d05 |
389 | |
390 | |
391 | =head1 COPYRIGHT |
392 | |
393 | This program is free software; you can redistribute it and/or modify |
394 | it under the same terms as Perl itself. |
9cf41c4d |
395 | |
396 | =cut |
397 | EOT |
398 | |
399 | close OUT or die $!; |