| File | /usr/local/lib/perl5/5.10.1/darwin-2level/DynaLoader.pm |
| Statements Executed | 343 |
| Statement Execution Time | 23.9ms |
| Calls | P | F | Exclusive Time |
Inclusive Time |
Subroutine |
|---|---|---|---|---|---|
| 8 | 1 | 2 | 20.3ms | 20.3ms | DynaLoader::dl_load_file (xsub) |
| 8 | 8 | 8 | 817µs | 22.8ms | DynaLoader::bootstrap |
| 16 | 2 | 2 | 309µs | 309µs | DynaLoader::CORE:subst (opcode) |
| 26 | 1 | 2 | 139µs | 139µs | DynaLoader::CORE:ftdir (opcode) |
| 8 | 1 | 2 | 90µs | 90µs | DynaLoader::CORE:ftfile (opcode) |
| 16 | 2 | 2 | 83µs | 83µs | DynaLoader::dl_find_symbol (xsub) |
| 8 | 1 | 2 | 56µs | 56µs | DynaLoader::dl_install_xsub (xsub) |
| 8 | 1 | 2 | 54µs | 54µs | DynaLoader::CORE:ftsize (opcode) |
| 8 | 1 | 2 | 17µs | 17µs | DynaLoader::dl_undef_symbols (xsub) |
| 8 | 1 | 1 | 15µs | 15µs | DynaLoader::dl_load_flags |
| 1 | 1 | 1 | 12µs | 28µs | DynaLoader::BEGIN@25 |
| 1 | 1 | 1 | 9µs | 9µs | DynaLoader::BEGIN@18 |
| 0 | 0 | 0 | 0s | 0s | DynaLoader::bootstrap_inherit |
| 0 | 0 | 0 | 0s | 0s | DynaLoader::croak |
| Line | State ments |
Time on line |
Calls | Time in subs |
Code |
|---|---|---|---|---|---|
| 1 | |||||
| 2 | # Generated from DynaLoader_pm.PL | ||||
| 3 | |||||
| 4 | package DynaLoader; | ||||
| 5 | |||||
| 6 | # And Gandalf said: 'Many folk like to know beforehand what is to | ||||
| 7 | # be set on the table; but those who have laboured to prepare the | ||||
| 8 | # feast like to keep their secret; for wonder makes the words of | ||||
| 9 | # praise louder.' | ||||
| 10 | |||||
| 11 | # (Quote from Tolkien suggested by Anno Siegel.) | ||||
| 12 | # | ||||
| 13 | # See pod text at end of file for documentation. | ||||
| 14 | # See also ext/DynaLoader/README in source tree for other information. | ||||
| 15 | # | ||||
| 16 | # Tim.Bunce@ig.co.uk, August 1994 | ||||
| 17 | |||||
| 18 | # spent 9µs within DynaLoader::BEGIN@18 which was called
# once (9µs+0s) by base::import at line 20 | ||||
| 19 | 1 | 5µs | $VERSION = '1.10'; | ||
| 20 | 1 | 44µs | 1 | 9µs | } # spent 9µs making 1 call to DynaLoader::BEGIN@18 |
| 21 | |||||
| 22 | 1 | 75µs | require AutoLoader; | ||
| 23 | 1 | 2µs | *AUTOLOAD = \&AutoLoader::AUTOLOAD; | ||
| 24 | |||||
| 25 | 3 | 854µs | 2 | 44µs | # spent 28µs (12+16) within DynaLoader::BEGIN@25 which was called
# once (12µs+16µs) by base::import at line 25 # spent 28µs making 1 call to DynaLoader::BEGIN@25
# spent 16µs making 1 call to Config::import |
| 26 | |||||
| 27 | # enable debug/trace messages from DynaLoader perl code | ||||
| 28 | 1 | 1µs | $dl_debug = $ENV{PERL_DL_DEBUG} || 0 unless defined $dl_debug; | ||
| 29 | |||||
| 30 | # | ||||
| 31 | # Flags to alter dl_load_file behaviour. Assigned bits: | ||||
| 32 | # 0x01 make symbols available for linking later dl_load_file's. | ||||
| 33 | # (only known to work on Solaris 2 using dlopen(RTLD_GLOBAL)) | ||||
| 34 | # (ignored under VMS; effect is built-in to image linking) | ||||
| 35 | # | ||||
| 36 | # This is called as a class method $module->dl_load_flags. The | ||||
| 37 | # definition here will be inherited and result on "default" loading | ||||
| 38 | # behaviour unless a sub-class of DynaLoader defines its own version. | ||||
| 39 | # | ||||
| 40 | |||||
| 41 | 8 | 24µs | # spent 15µs within DynaLoader::dl_load_flags which was called 8 times, avg 2µs/call:
# 8 times (15µs+0s) by DynaLoader::bootstrap at line 204, avg 2µs/call | ||
| 42 | |||||
| 43 | 1 | 16µs | 3 | 1.34ms | ($dl_dlext, $dl_so, $dlsrc) = @Config::Config{qw(dlext so dlsrc)}; # spent 1.34ms making 3 calls to Config::FETCH, avg 448µs/call |
| 44 | |||||
| 45 | |||||
| 46 | 1 | 200ns | $do_expand = 0; | ||
| 47 | |||||
| 48 | |||||
| 49 | |||||
| 50 | 1 | 1µs | @dl_require_symbols = (); # names of symbols we need | ||
| 51 | 1 | 200ns | @dl_resolve_using = (); # names of files to link with | ||
| 52 | 1 | 100ns | @dl_library_path = (); # path to look for files | ||
| 53 | |||||
| 54 | #XSLoader.pm may have added elements before we were required | ||||
| 55 | #@dl_shared_objects = (); # shared objects for symbols we have | ||||
| 56 | #@dl_librefs = (); # things we have loaded | ||||
| 57 | #@dl_modules = (); # Modules we have loaded | ||||
| 58 | |||||
| 59 | # This is a fix to support DLD's unfortunate desire to relink -lc | ||||
| 60 | 1 | 100ns | @dl_resolve_using = dl_findfile('-lc') if $dlsrc eq "dl_dld.xs"; | ||
| 61 | |||||
| 62 | # Initialise @dl_library_path with the 'standard' library path | ||||
| 63 | # for this platform as determined by Configure. | ||||
| 64 | |||||
| 65 | 1 | 6µs | 1 | 2µs | push(@dl_library_path, split(' ', $Config::Config{libpth})); # spent 2µs making 1 call to Config::FETCH |
| 66 | |||||
| 67 | |||||
| 68 | 1 | 3µs | 1 | 2µs | my $ldlibpthname = $Config::Config{ldlibpthname}; # spent 2µs making 1 call to Config::FETCH |
| 69 | 1 | 3µs | 1 | 1µs | my $ldlibpthname_defined = defined $Config::Config{ldlibpthname}; # spent 1µs making 1 call to Config::FETCH |
| 70 | 1 | 3µs | 1 | 2µs | my $pthsep = $Config::Config{path_sep}; # spent 2µs making 1 call to Config::FETCH |
| 71 | |||||
| 72 | # Add to @dl_library_path any extra directories we can gather from environment | ||||
| 73 | # during runtime. | ||||
| 74 | |||||
| 75 | 1 | 1µs | if ($ldlibpthname_defined && | ||
| 76 | exists $ENV{$ldlibpthname}) { | ||||
| 77 | push(@dl_library_path, split(/$pthsep/, $ENV{$ldlibpthname})); | ||||
| 78 | } | ||||
| 79 | |||||
| 80 | # E.g. HP-UX supports both its native SHLIB_PATH *and* LD_LIBRARY_PATH. | ||||
| 81 | |||||
| 82 | 1 | 600ns | if ($ldlibpthname_defined && | ||
| 83 | $ldlibpthname ne 'LD_LIBRARY_PATH' && | ||||
| 84 | exists $ENV{LD_LIBRARY_PATH}) { | ||||
| 85 | push(@dl_library_path, split(/$pthsep/, $ENV{LD_LIBRARY_PATH})); | ||||
| 86 | } | ||||
| 87 | |||||
| 88 | |||||
| 89 | # No prizes for guessing why we don't say 'bootstrap DynaLoader;' here. | ||||
| 90 | # NOTE: All dl_*.xs (including dl_none.xs) define a dl_error() XSUB | ||||
| 91 | 1 | 700ns | boot_DynaLoader('DynaLoader') if defined(&boot_DynaLoader) && | ||
| 92 | !defined(&dl_error); | ||||
| 93 | |||||
| 94 | 1 | 100ns | if ($dl_debug) { | ||
| 95 | print STDERR "DynaLoader.pm loaded (@INC, @dl_library_path)\n"; | ||||
| 96 | print STDERR "DynaLoader not linked into this perl\n" | ||||
| 97 | unless defined(&boot_DynaLoader); | ||||
| 98 | } | ||||
| 99 | |||||
| 100 | 1 | 37µs | 1; # End of main code | ||
| 101 | |||||
| 102 | |||||
| 103 | sub croak { require Carp; Carp::croak(@_) } | ||||
| 104 | |||||
| 105 | sub bootstrap_inherit { | ||||
| 106 | 4 | 20µs | my $module = $_[0]; | ||
| 107 | local *isa = *{"$module\::ISA"}; | ||||
| 108 | local @isa = (@isa, 'DynaLoader'); | ||||
| 109 | # Cannot goto due to delocalization. Will report errors on a wrong line? | ||||
| 110 | bootstrap(@_); # spent 238µs making 1 call to DynaLoader::bootstrap | ||||
| 111 | } | ||||
| 112 | |||||
| 113 | # The bootstrap function cannot be autoloaded (without complications) | ||||
| 114 | # so we define it here: | ||||
| 115 | |||||
| 116 | # spent 22.8ms (817µs+22.0) within DynaLoader::bootstrap which was called 8 times, avg 2.85ms/call:
# once (119µs+20.1ms) by SimpleDB::Client::BEGIN@48 at line 18 of XML/Bare.pm
# once (118µs+380µs) by Moose::Exporter::BEGIN@12 at line 24 of List/MoreUtils.pm
# once (153µs+344µs) by Data::OptList::BEGIN@7 at line 88 of Params/Util.pm
# once (104µs+250µs) by SimpleDB::Client::BEGIN@47 at line 171 of Digest/SHA.pm
# once (89µs+262µs) by SimpleDB::Client::BEGIN@51 at line 65 of Time/HiRes.pm
# once (81µs+254µs) by LWP::UserAgent::BEGIN@10 at line 67 of Storable.pm
# once (83µs+212µs) by Class::MOP::Mixin::HasMethods::BEGIN@12 at line 55 of Sub/Name.pm
# once (69µs+169µs) by Moose::BEGIN@14 at line 110 | ||||
| 117 | # use local vars to enable $module.bs script to edit values | ||||
| 118 | 240 | 22.4ms | local(@args) = @_; | ||
| 119 | local($module) = $args[0]; | ||||
| 120 | local(@dirs, $file); | ||||
| 121 | |||||
| 122 | unless ($module) { | ||||
| 123 | require Carp; | ||||
| 124 | Carp::confess("Usage: DynaLoader::bootstrap(module)"); | ||||
| 125 | } | ||||
| 126 | |||||
| 127 | # A common error on platforms which don't support dynamic loading. | ||||
| 128 | # Since it's fatal and potentially confusing we give a detailed message. | ||||
| 129 | croak("Can't load module $module, dynamic loading not available in this perl.\n". | ||||
| 130 | " (You may need to build a new perl executable which either supports\n". | ||||
| 131 | " dynamic loading or has the $module module statically linked into it.)\n") | ||||
| 132 | unless defined(&dl_load_file); | ||||
| 133 | |||||
| 134 | |||||
| 135 | |||||
| 136 | my @modparts = split(/::/,$module); | ||||
| 137 | my $modfname = $modparts[-1]; | ||||
| 138 | |||||
| 139 | # Some systems have restrictions on files names for DLL's etc. | ||||
| 140 | # mod2fname returns appropriate file base name (typically truncated) | ||||
| 141 | # It may also edit @modparts if required. | ||||
| 142 | $modfname = &mod2fname(\@modparts) if defined &mod2fname; | ||||
| 143 | |||||
| 144 | |||||
| 145 | |||||
| 146 | my $modpname = join('/',@modparts); | ||||
| 147 | |||||
| 148 | print STDERR "DynaLoader::bootstrap for $module ", | ||||
| 149 | "(auto/$modpname/$modfname.$dl_dlext)\n" | ||||
| 150 | if $dl_debug; | ||||
| 151 | |||||
| 152 | foreach (@INC) { | ||||
| 153 | |||||
| 154 | |||||
| 155 | 68 | 396µs | my $dir = "$_/auto/$modpname"; | ||
| 156 | |||||
| 157 | |||||
| 158 | next unless -d $dir; # skip over uninteresting directories # spent 139µs making 26 calls to DynaLoader::CORE:ftdir, avg 5µs/call | ||||
| 159 | |||||
| 160 | # check for common cases to avoid autoload of dl_findfile | ||||
| 161 | my $try = "$dir/$modfname.$dl_dlext"; | ||||
| 162 | last if $file = ($do_expand) ? dl_expandspec($try) : ((-f $try) && $try); # spent 90µs making 8 calls to DynaLoader::CORE:ftfile, avg 11µs/call | ||||
| 163 | |||||
| 164 | # no luck here, save dir for possible later dl_findfile search | ||||
| 165 | push @dirs, $dir; | ||||
| 166 | } | ||||
| 167 | # last resort, let dl_findfile have a go in all known locations | ||||
| 168 | $file = dl_findfile(map("-L$_",@dirs,@INC), $modfname) unless $file; | ||||
| 169 | |||||
| 170 | croak("Can't locate loadable object for module $module in \@INC (\@INC contains: @INC)") | ||||
| 171 | unless $file; # wording similar to error from 'require' | ||||
| 172 | |||||
| 173 | |||||
| 174 | my $bootname = "boot_$module"; | ||||
| 175 | $bootname =~ s/\W/_/g; # spent 27µs making 8 calls to DynaLoader::CORE:subst, avg 3µs/call | ||||
| 176 | @dl_require_symbols = ($bootname); | ||||
| 177 | |||||
| 178 | # Execute optional '.bootstrap' perl script for this module. | ||||
| 179 | # The .bs file can be used to configure @dl_resolve_using etc to | ||||
| 180 | # match the needs of the individual module on this architecture. | ||||
| 181 | my $bs = $file; | ||||
| 182 | $bs =~ s/(\.\w+)?(;\d*)?$/\.bs/; # look for .bs 'beside' the library # spent 282µs making 8 calls to DynaLoader::CORE:subst, avg 35µs/call | ||||
| 183 | if (-s $bs) { # only read file if it's not empty # spent 54µs making 8 calls to DynaLoader::CORE:ftsize, avg 7µs/call | ||||
| 184 | print STDERR "BS: $bs ($^O, $dlsrc)\n" if $dl_debug; | ||||
| 185 | eval { do $bs; }; | ||||
| 186 | warn "$bs: $@\n" if $@; | ||||
| 187 | } | ||||
| 188 | |||||
| 189 | my $boot_symbol_ref; | ||||
| 190 | |||||
| 191 | |||||
| 192 | if ($boot_symbol_ref = dl_find_symbol(0, $bootname)) { # spent 62µs making 8 calls to DynaLoader::dl_find_symbol, avg 8µs/call | ||||
| 193 | goto boot; #extension library has already been loaded, e.g. darwin | ||||
| 194 | } | ||||
| 195 | |||||
| 196 | |||||
| 197 | # Many dynamic extension loading problems will appear to come from | ||||
| 198 | # this section of code: XYZ failed at line 123 of DynaLoader.pm. | ||||
| 199 | # Often these errors are actually occurring in the initialisation | ||||
| 200 | # C code of the extension XS file. Perl reports the error as being | ||||
| 201 | # in this perl code simply because this was the last perl code | ||||
| 202 | # it executed. | ||||
| 203 | |||||
| 204 | my $libref = dl_load_file($file, $module->dl_load_flags) or # spent 20.3ms making 8 calls to DynaLoader::dl_load_file, avg 2.53ms/call
# spent 15µs making 8 calls to DynaLoader::dl_load_flags, avg 2µs/call | ||||
| 205 | croak("Can't load '$file' for module $module: ".dl_error()); | ||||
| 206 | |||||
| 207 | push(@dl_librefs,$libref); # record loaded object | ||||
| 208 | |||||
| 209 | my @unresolved = dl_undef_symbols(); # spent 17µs making 8 calls to DynaLoader::dl_undef_symbols, avg 2µs/call | ||||
| 210 | if (@unresolved) { | ||||
| 211 | require Carp; | ||||
| 212 | Carp::carp("Undefined symbols present after loading $file: @unresolved\n"); | ||||
| 213 | } | ||||
| 214 | |||||
| 215 | $boot_symbol_ref = dl_find_symbol($libref, $bootname) or # spent 21µs making 8 calls to DynaLoader::dl_find_symbol, avg 3µs/call | ||||
| 216 | croak("Can't find '$bootname' symbol in $file\n"); | ||||
| 217 | |||||
| 218 | push(@dl_modules, $module); # record loaded module | ||||
| 219 | |||||
| 220 | boot: # spent 56µs making 8 calls to DynaLoader::dl_install_xsub, avg 7µs/call | ||||
| 221 | my $xs = dl_install_xsub("${module}::bootstrap", $boot_symbol_ref, $file); | ||||
| 222 | |||||
| 223 | # See comment block above | ||||
| 224 | |||||
| 225 | push(@dl_shared_objects, $file); # record files loaded | ||||
| 226 | |||||
| 227 | &$xs(@args); # spent 557µs making 1 call to XML::Bare::bootstrap
# spent 97µs making 1 call to Digest::SHA::bootstrap
# spent 94µs making 1 call to List::MoreUtils::bootstrap
# spent 85µs making 1 call to Storable::bootstrap
# spent 66µs making 1 call to Time::HiRes::bootstrap
# spent 51µs making 1 call to Params::Util::bootstrap
# spent 16µs making 1 call to Sub::Name::bootstrap
# spent 15µs making 1 call to Moose::bootstrap | ||||
| 228 | } | ||||
| 229 | |||||
| 230 | |||||
| 231 | #sub _check_file { # private utility to handle dl_expandspec vs -f tests | ||||
| 232 | # my($file) = @_; | ||||
| 233 | # return $file if (!$do_expand && -f $file); # the common case | ||||
| 234 | # return $file if ( $do_expand && ($file=dl_expandspec($file))); | ||||
| 235 | # return undef; | ||||
| 236 | #} | ||||
| 237 | |||||
| 238 | |||||
| 239 | # Let autosplit and the autoloader deal with these functions: | ||||
| 240 | __END__ | ||||
| 241 | |||||
| 242 | |||||
| 243 | sub dl_findfile { | ||||
| 244 | # Read ext/DynaLoader/DynaLoader.doc for detailed information. | ||||
| 245 | # This function does not automatically consider the architecture | ||||
| 246 | # or the perl library auto directories. | ||||
| 247 | my (@args) = @_; | ||||
| 248 | my (@dirs, $dir); # which directories to search | ||||
| 249 | my (@found); # full paths to real files we have found | ||||
| 250 | #my $dl_ext= 'bundle'; # $Config::Config{'dlext'} suffix for perl extensions | ||||
| 251 | #my $dl_so = 'dylib'; # $Config::Config{'so'} suffix for shared libraries | ||||
| 252 | |||||
| 253 | print STDERR "dl_findfile(@args)\n" if $dl_debug; | ||||
| 254 | |||||
| 255 | # accumulate directories but process files as they appear | ||||
| 256 | arg: foreach(@args) { | ||||
| 257 | # Special fast case: full filepath requires no search | ||||
| 258 | |||||
| 259 | |||||
| 260 | |||||
| 261 | if (m:/: && -f $_) { | ||||
| 262 | push(@found,$_); | ||||
| 263 | last arg unless wantarray; | ||||
| 264 | next; | ||||
| 265 | } | ||||
| 266 | |||||
| 267 | |||||
| 268 | # Deal with directories first: | ||||
| 269 | # Using a -L prefix is the preferred option (faster and more robust) | ||||
| 270 | if (m:^-L:) { s/^-L//; push(@dirs, $_); next; } | ||||
| 271 | |||||
| 272 | |||||
| 273 | |||||
| 274 | # Otherwise we try to try to spot directories by a heuristic | ||||
| 275 | # (this is a more complicated issue than it first appears) | ||||
| 276 | if (m:/: && -d $_) { push(@dirs, $_); next; } | ||||
| 277 | |||||
| 278 | |||||
| 279 | |||||
| 280 | # Only files should get this far... | ||||
| 281 | my(@names, $name); # what filenames to look for | ||||
| 282 | if (m:-l: ) { # convert -lname to appropriate library name | ||||
| 283 | s/-l//; | ||||
| 284 | push(@names,"lib$_.$dl_so"); | ||||
| 285 | push(@names,"lib$_.a"); | ||||
| 286 | } else { # Umm, a bare name. Try various alternatives: | ||||
| 287 | # these should be ordered with the most likely first | ||||
| 288 | push(@names,"$_.$dl_dlext") unless m/\.$dl_dlext$/o; | ||||
| 289 | push(@names,"$_.$dl_so") unless m/\.$dl_so$/o; | ||||
| 290 | push(@names,"lib$_.$dl_so") unless m:/:; | ||||
| 291 | push(@names,"$_.a") if !m/\.a$/ and $dlsrc eq "dl_dld.xs"; | ||||
| 292 | push(@names, $_); | ||||
| 293 | } | ||||
| 294 | my $dirsep = '/'; | ||||
| 295 | |||||
| 296 | foreach $dir (@dirs, @dl_library_path) { | ||||
| 297 | next unless -d $dir; | ||||
| 298 | |||||
| 299 | foreach $name (@names) { | ||||
| 300 | my($file) = "$dir$dirsep$name"; | ||||
| 301 | print STDERR " checking in $dir for $name\n" if $dl_debug; | ||||
| 302 | $file = ($do_expand) ? dl_expandspec($file) : (-f $file && $file); | ||||
| 303 | #$file = _check_file($file); | ||||
| 304 | if ($file) { | ||||
| 305 | push(@found, $file); | ||||
| 306 | next arg; # no need to look any further | ||||
| 307 | } | ||||
| 308 | } | ||||
| 309 | } | ||||
| 310 | } | ||||
| 311 | if ($dl_debug) { | ||||
| 312 | foreach(@dirs) { | ||||
| 313 | print STDERR " dl_findfile ignored non-existent directory: $_\n" unless -d $_; | ||||
| 314 | } | ||||
| 315 | print STDERR "dl_findfile found: @found\n"; | ||||
| 316 | } | ||||
| 317 | return $found[0] unless wantarray; | ||||
| 318 | @found; | ||||
| 319 | } | ||||
| 320 | |||||
| 321 | |||||
| 322 | sub dl_expandspec { | ||||
| 323 | my($spec) = @_; | ||||
| 324 | # Optional function invoked if DynaLoader.pm sets $do_expand. | ||||
| 325 | # Most systems do not require or use this function. | ||||
| 326 | # Some systems may implement it in the dl_*.xs file in which case | ||||
| 327 | # this autoload version will not be called but is harmless. | ||||
| 328 | |||||
| 329 | # This function is designed to deal with systems which treat some | ||||
| 330 | # 'filenames' in a special way. For example VMS 'Logical Names' | ||||
| 331 | # (something like unix environment variables - but different). | ||||
| 332 | # This function should recognise such names and expand them into | ||||
| 333 | # full file paths. | ||||
| 334 | # Must return undef if $spec is invalid or file does not exist. | ||||
| 335 | |||||
| 336 | my $file = $spec; # default output to input | ||||
| 337 | |||||
| 338 | |||||
| 339 | return undef unless -f $file; | ||||
| 340 | |||||
| 341 | print STDERR "dl_expandspec($spec) => $file\n" if $dl_debug; | ||||
| 342 | $file; | ||||
| 343 | } | ||||
| 344 | |||||
| 345 | sub dl_find_symbol_anywhere | ||||
| 346 | { | ||||
| 347 | my $sym = shift; | ||||
| 348 | my $libref; | ||||
| 349 | foreach $libref (@dl_librefs) { | ||||
| 350 | my $symref = dl_find_symbol($libref,$sym); | ||||
| 351 | return $symref if $symref; | ||||
| 352 | } | ||||
| 353 | return undef; | ||||
| 354 | } | ||||
| 355 | |||||
| 356 | =head1 NAME | ||||
| 357 | |||||
| 358 | DynaLoader - Dynamically load C libraries into Perl code | ||||
| 359 | |||||
| 360 | =head1 SYNOPSIS | ||||
| 361 | |||||
| 362 | package YourPackage; | ||||
| 363 | require DynaLoader; | ||||
| 364 | @ISA = qw(... DynaLoader ...); | ||||
| 365 | bootstrap YourPackage; | ||||
| 366 | |||||
| 367 | # optional method for 'global' loading | ||||
| 368 | sub dl_load_flags { 0x01 } | ||||
| 369 | |||||
| 370 | |||||
| 371 | =head1 DESCRIPTION | ||||
| 372 | |||||
| 373 | This document defines a standard generic interface to the dynamic | ||||
| 374 | linking mechanisms available on many platforms. Its primary purpose is | ||||
| 375 | to implement automatic dynamic loading of Perl modules. | ||||
| 376 | |||||
| 377 | This document serves as both a specification for anyone wishing to | ||||
| 378 | implement the DynaLoader for a new platform and as a guide for | ||||
| 379 | anyone wishing to use the DynaLoader directly in an application. | ||||
| 380 | |||||
| 381 | The DynaLoader is designed to be a very simple high-level | ||||
| 382 | interface that is sufficiently general to cover the requirements | ||||
| 383 | of SunOS, HP-UX, NeXT, Linux, VMS and other platforms. | ||||
| 384 | |||||
| 385 | It is also hoped that the interface will cover the needs of OS/2, NT | ||||
| 386 | etc and also allow pseudo-dynamic linking (using C<ld -A> at runtime). | ||||
| 387 | |||||
| 388 | It must be stressed that the DynaLoader, by itself, is practically | ||||
| 389 | useless for accessing non-Perl libraries because it provides almost no | ||||
| 390 | Perl-to-C 'glue'. There is, for example, no mechanism for calling a C | ||||
| 391 | library function or supplying arguments. A C::DynaLib module | ||||
| 392 | is available from CPAN sites which performs that function for some | ||||
| 393 | common system types. And since the year 2000, there's also Inline::C, | ||||
| 394 | a module that allows you to write Perl subroutines in C. Also available | ||||
| 395 | from your local CPAN site. | ||||
| 396 | |||||
| 397 | DynaLoader Interface Summary | ||||
| 398 | |||||
| 399 | @dl_library_path | ||||
| 400 | @dl_resolve_using | ||||
| 401 | @dl_require_symbols | ||||
| 402 | $dl_debug | ||||
| 403 | @dl_librefs | ||||
| 404 | @dl_modules | ||||
| 405 | @dl_shared_objects | ||||
| 406 | Implemented in: | ||||
| 407 | bootstrap($modulename) Perl | ||||
| 408 | @filepaths = dl_findfile(@names) Perl | ||||
| 409 | $flags = $modulename->dl_load_flags Perl | ||||
| 410 | $symref = dl_find_symbol_anywhere($symbol) Perl | ||||
| 411 | |||||
| 412 | $libref = dl_load_file($filename, $flags) C | ||||
| 413 | $status = dl_unload_file($libref) C | ||||
| 414 | $symref = dl_find_symbol($libref, $symbol) C | ||||
| 415 | @symbols = dl_undef_symbols() C | ||||
| 416 | dl_install_xsub($name, $symref [, $filename]) C | ||||
| 417 | $message = dl_error C | ||||
| 418 | |||||
| 419 | =over 4 | ||||
| 420 | |||||
| 421 | =item @dl_library_path | ||||
| 422 | |||||
| 423 | The standard/default list of directories in which dl_findfile() will | ||||
| 424 | search for libraries etc. Directories are searched in order: | ||||
| 425 | $dl_library_path[0], [1], ... etc | ||||
| 426 | |||||
| 427 | @dl_library_path is initialised to hold the list of 'normal' directories | ||||
| 428 | (F</usr/lib>, etc) determined by B<Configure> (C<$Config{'libpth'}>). This should | ||||
| 429 | ensure portability across a wide range of platforms. | ||||
| 430 | |||||
| 431 | @dl_library_path should also be initialised with any other directories | ||||
| 432 | that can be determined from the environment at runtime (such as | ||||
| 433 | LD_LIBRARY_PATH for SunOS). | ||||
| 434 | |||||
| 435 | After initialisation @dl_library_path can be manipulated by an | ||||
| 436 | application using push and unshift before calling dl_findfile(). | ||||
| 437 | Unshift can be used to add directories to the front of the search order | ||||
| 438 | either to save search time or to override libraries with the same name | ||||
| 439 | in the 'normal' directories. | ||||
| 440 | |||||
| 441 | The load function that dl_load_file() calls may require an absolute | ||||
| 442 | pathname. The dl_findfile() function and @dl_library_path can be | ||||
| 443 | used to search for and return the absolute pathname for the | ||||
| 444 | library/object that you wish to load. | ||||
| 445 | |||||
| 446 | =item @dl_resolve_using | ||||
| 447 | |||||
| 448 | A list of additional libraries or other shared objects which can be | ||||
| 449 | used to resolve any undefined symbols that might be generated by a | ||||
| 450 | later call to load_file(). | ||||
| 451 | |||||
| 452 | This is only required on some platforms which do not handle dependent | ||||
| 453 | libraries automatically. For example the Socket Perl extension | ||||
| 454 | library (F<auto/Socket/Socket.so>) contains references to many socket | ||||
| 455 | functions which need to be resolved when it's loaded. Most platforms | ||||
| 456 | will automatically know where to find the 'dependent' library (e.g., | ||||
| 457 | F</usr/lib/libsocket.so>). A few platforms need to be told the | ||||
| 458 | location of the dependent library explicitly. Use @dl_resolve_using | ||||
| 459 | for this. | ||||
| 460 | |||||
| 461 | Example usage: | ||||
| 462 | |||||
| 463 | @dl_resolve_using = dl_findfile('-lsocket'); | ||||
| 464 | |||||
| 465 | =item @dl_require_symbols | ||||
| 466 | |||||
| 467 | A list of one or more symbol names that are in the library/object file | ||||
| 468 | to be dynamically loaded. This is only required on some platforms. | ||||
| 469 | |||||
| 470 | =item @dl_librefs | ||||
| 471 | |||||
| 472 | An array of the handles returned by successful calls to dl_load_file(), | ||||
| 473 | made by bootstrap, in the order in which they were loaded. | ||||
| 474 | Can be used with dl_find_symbol() to look for a symbol in any of | ||||
| 475 | the loaded files. | ||||
| 476 | |||||
| 477 | =item @dl_modules | ||||
| 478 | |||||
| 479 | An array of module (package) names that have been bootstrap'ed. | ||||
| 480 | |||||
| 481 | =item @dl_shared_objects | ||||
| 482 | |||||
| 483 | An array of file names for the shared objects that were loaded. | ||||
| 484 | |||||
| 485 | =item dl_error() | ||||
| 486 | |||||
| 487 | Syntax: | ||||
| 488 | |||||
| 489 | $message = dl_error(); | ||||
| 490 | |||||
| 491 | Error message text from the last failed DynaLoader function. Note | ||||
| 492 | that, similar to errno in unix, a successful function call does not | ||||
| 493 | reset this message. | ||||
| 494 | |||||
| 495 | Implementations should detect the error as soon as it occurs in any of | ||||
| 496 | the other functions and save the corresponding message for later | ||||
| 497 | retrieval. This will avoid problems on some platforms (such as SunOS) | ||||
| 498 | where the error message is very temporary (e.g., dlerror()). | ||||
| 499 | |||||
| 500 | =item $dl_debug | ||||
| 501 | |||||
| 502 | Internal debugging messages are enabled when $dl_debug is set true. | ||||
| 503 | Currently setting $dl_debug only affects the Perl side of the | ||||
| 504 | DynaLoader. These messages should help an application developer to | ||||
| 505 | resolve any DynaLoader usage problems. | ||||
| 506 | |||||
| 507 | $dl_debug is set to C<$ENV{'PERL_DL_DEBUG'}> if defined. | ||||
| 508 | |||||
| 509 | For the DynaLoader developer/porter there is a similar debugging | ||||
| 510 | variable added to the C code (see dlutils.c) and enabled if Perl was | ||||
| 511 | built with the B<-DDEBUGGING> flag. This can also be set via the | ||||
| 512 | PERL_DL_DEBUG environment variable. Set to 1 for minimal information or | ||||
| 513 | higher for more. | ||||
| 514 | |||||
| 515 | =item dl_findfile() | ||||
| 516 | |||||
| 517 | Syntax: | ||||
| 518 | |||||
| 519 | @filepaths = dl_findfile(@names) | ||||
| 520 | |||||
| 521 | Determine the full paths (including file suffix) of one or more | ||||
| 522 | loadable files given their generic names and optionally one or more | ||||
| 523 | directories. Searches directories in @dl_library_path by default and | ||||
| 524 | returns an empty list if no files were found. | ||||
| 525 | |||||
| 526 | Names can be specified in a variety of platform independent forms. Any | ||||
| 527 | names in the form B<-lname> are converted into F<libname.*>, where F<.*> is | ||||
| 528 | an appropriate suffix for the platform. | ||||
| 529 | |||||
| 530 | If a name does not already have a suitable prefix and/or suffix then | ||||
| 531 | the corresponding file will be searched for by trying combinations of | ||||
| 532 | prefix and suffix appropriate to the platform: "$name.o", "lib$name.*" | ||||
| 533 | and "$name". | ||||
| 534 | |||||
| 535 | If any directories are included in @names they are searched before | ||||
| 536 | @dl_library_path. Directories may be specified as B<-Ldir>. Any other | ||||
| 537 | names are treated as filenames to be searched for. | ||||
| 538 | |||||
| 539 | Using arguments of the form C<-Ldir> and C<-lname> is recommended. | ||||
| 540 | |||||
| 541 | Example: | ||||
| 542 | |||||
| 543 | @dl_resolve_using = dl_findfile(qw(-L/usr/5lib -lposix)); | ||||
| 544 | |||||
| 545 | |||||
| 546 | =item dl_expandspec() | ||||
| 547 | |||||
| 548 | Syntax: | ||||
| 549 | |||||
| 550 | $filepath = dl_expandspec($spec) | ||||
| 551 | |||||
| 552 | Some unusual systems, such as VMS, require special filename handling in | ||||
| 553 | order to deal with symbolic names for files (i.e., VMS's Logical Names). | ||||
| 554 | |||||
| 555 | To support these systems a dl_expandspec() function can be implemented | ||||
| 556 | either in the F<dl_*.xs> file or code can be added to the autoloadable | ||||
| 557 | dl_expandspec() function in F<DynaLoader.pm>. See F<DynaLoader.pm> for | ||||
| 558 | more information. | ||||
| 559 | |||||
| 560 | =item dl_load_file() | ||||
| 561 | |||||
| 562 | Syntax: | ||||
| 563 | |||||
| 564 | $libref = dl_load_file($filename, $flags) | ||||
| 565 | |||||
| 566 | Dynamically load $filename, which must be the path to a shared object | ||||
| 567 | or library. An opaque 'library reference' is returned as a handle for | ||||
| 568 | the loaded object. Returns undef on error. | ||||
| 569 | |||||
| 570 | The $flags argument to alters dl_load_file behaviour. | ||||
| 571 | Assigned bits: | ||||
| 572 | |||||
| 573 | 0x01 make symbols available for linking later dl_load_file's. | ||||
| 574 | (only known to work on Solaris 2 using dlopen(RTLD_GLOBAL)) | ||||
| 575 | (ignored under VMS; this is a normal part of image linking) | ||||
| 576 | |||||
| 577 | (On systems that provide a handle for the loaded object such as SunOS | ||||
| 578 | and HPUX, $libref will be that handle. On other systems $libref will | ||||
| 579 | typically be $filename or a pointer to a buffer containing $filename. | ||||
| 580 | The application should not examine or alter $libref in any way.) | ||||
| 581 | |||||
| 582 | This is the function that does the real work. It should use the | ||||
| 583 | current values of @dl_require_symbols and @dl_resolve_using if required. | ||||
| 584 | |||||
| 585 | SunOS: dlopen($filename) | ||||
| 586 | HP-UX: shl_load($filename) | ||||
| 587 | Linux: dld_create_reference(@dl_require_symbols); dld_link($filename) | ||||
| 588 | NeXT: rld_load($filename, @dl_resolve_using) | ||||
| 589 | VMS: lib$find_image_symbol($filename,$dl_require_symbols[0]) | ||||
| 590 | |||||
| 591 | (The dlopen() function is also used by Solaris and some versions of | ||||
| 592 | Linux, and is a common choice when providing a "wrapper" on other | ||||
| 593 | mechanisms as is done in the OS/2 port.) | ||||
| 594 | |||||
| 595 | =item dl_unload_file() | ||||
| 596 | |||||
| 597 | Syntax: | ||||
| 598 | |||||
| 599 | $status = dl_unload_file($libref) | ||||
| 600 | |||||
| 601 | Dynamically unload $libref, which must be an opaque 'library reference' as | ||||
| 602 | returned from dl_load_file. Returns one on success and zero on failure. | ||||
| 603 | |||||
| 604 | This function is optional and may not necessarily be provided on all platforms. | ||||
| 605 | If it is defined, it is called automatically when the interpreter exits for | ||||
| 606 | every shared object or library loaded by DynaLoader::bootstrap. All such | ||||
| 607 | library references are stored in @dl_librefs by DynaLoader::Bootstrap as it | ||||
| 608 | loads the libraries. The files are unloaded in last-in, first-out order. | ||||
| 609 | |||||
| 610 | This unloading is usually necessary when embedding a shared-object perl (e.g. | ||||
| 611 | one configured with -Duseshrplib) within a larger application, and the perl | ||||
| 612 | interpreter is created and destroyed several times within the lifetime of the | ||||
| 613 | application. In this case it is possible that the system dynamic linker will | ||||
| 614 | unload and then subsequently reload the shared libperl without relocating any | ||||
| 615 | references to it from any files DynaLoaded by the previous incarnation of the | ||||
| 616 | interpreter. As a result, any shared objects opened by DynaLoader may point to | ||||
| 617 | a now invalid 'ghost' of the libperl shared object, causing apparently random | ||||
| 618 | memory corruption and crashes. This behaviour is most commonly seen when using | ||||
| 619 | Apache and mod_perl built with the APXS mechanism. | ||||
| 620 | |||||
| 621 | SunOS: dlclose($libref) | ||||
| 622 | HP-UX: ??? | ||||
| 623 | Linux: ??? | ||||
| 624 | NeXT: ??? | ||||
| 625 | VMS: ??? | ||||
| 626 | |||||
| 627 | (The dlclose() function is also used by Solaris and some versions of | ||||
| 628 | Linux, and is a common choice when providing a "wrapper" on other | ||||
| 629 | mechanisms as is done in the OS/2 port.) | ||||
| 630 | |||||
| 631 | =item dl_load_flags() | ||||
| 632 | |||||
| 633 | Syntax: | ||||
| 634 | |||||
| 635 | $flags = dl_load_flags $modulename; | ||||
| 636 | |||||
| 637 | Designed to be a method call, and to be overridden by a derived class | ||||
| 638 | (i.e. a class which has DynaLoader in its @ISA). The definition in | ||||
| 639 | DynaLoader itself returns 0, which produces standard behavior from | ||||
| 640 | dl_load_file(). | ||||
| 641 | |||||
| 642 | =item dl_find_symbol() | ||||
| 643 | |||||
| 644 | Syntax: | ||||
| 645 | |||||
| 646 | $symref = dl_find_symbol($libref, $symbol) | ||||
| 647 | |||||
| 648 | Return the address of the symbol $symbol or C<undef> if not found. If the | ||||
| 649 | target system has separate functions to search for symbols of different | ||||
| 650 | types then dl_find_symbol() should search for function symbols first and | ||||
| 651 | then other types. | ||||
| 652 | |||||
| 653 | The exact manner in which the address is returned in $symref is not | ||||
| 654 | currently defined. The only initial requirement is that $symref can | ||||
| 655 | be passed to, and understood by, dl_install_xsub(). | ||||
| 656 | |||||
| 657 | SunOS: dlsym($libref, $symbol) | ||||
| 658 | HP-UX: shl_findsym($libref, $symbol) | ||||
| 659 | Linux: dld_get_func($symbol) and/or dld_get_symbol($symbol) | ||||
| 660 | NeXT: rld_lookup("_$symbol") | ||||
| 661 | VMS: lib$find_image_symbol($libref,$symbol) | ||||
| 662 | |||||
| 663 | |||||
| 664 | =item dl_find_symbol_anywhere() | ||||
| 665 | |||||
| 666 | Syntax: | ||||
| 667 | |||||
| 668 | $symref = dl_find_symbol_anywhere($symbol) | ||||
| 669 | |||||
| 670 | Applies dl_find_symbol() to the members of @dl_librefs and returns | ||||
| 671 | the first match found. | ||||
| 672 | |||||
| 673 | =item dl_undef_symbols() | ||||
| 674 | |||||
| 675 | Example | ||||
| 676 | |||||
| 677 | @symbols = dl_undef_symbols() | ||||
| 678 | |||||
| 679 | Return a list of symbol names which remain undefined after load_file(). | ||||
| 680 | Returns C<()> if not known. Don't worry if your platform does not provide | ||||
| 681 | a mechanism for this. Most do not need it and hence do not provide it, | ||||
| 682 | they just return an empty list. | ||||
| 683 | |||||
| 684 | |||||
| 685 | =item dl_install_xsub() | ||||
| 686 | |||||
| 687 | Syntax: | ||||
| 688 | |||||
| 689 | dl_install_xsub($perl_name, $symref [, $filename]) | ||||
| 690 | |||||
| 691 | Create a new Perl external subroutine named $perl_name using $symref as | ||||
| 692 | a pointer to the function which implements the routine. This is simply | ||||
| 693 | a direct call to newXSUB(). Returns a reference to the installed | ||||
| 694 | function. | ||||
| 695 | |||||
| 696 | The $filename parameter is used by Perl to identify the source file for | ||||
| 697 | the function if required by die(), caller() or the debugger. If | ||||
| 698 | $filename is not defined then "DynaLoader" will be used. | ||||
| 699 | |||||
| 700 | |||||
| 701 | =item bootstrap() | ||||
| 702 | |||||
| 703 | Syntax: | ||||
| 704 | |||||
| 705 | bootstrap($module) | ||||
| 706 | |||||
| 707 | This is the normal entry point for automatic dynamic loading in Perl. | ||||
| 708 | |||||
| 709 | It performs the following actions: | ||||
| 710 | |||||
| 711 | =over 8 | ||||
| 712 | |||||
| 713 | =item * | ||||
| 714 | |||||
| 715 | locates an auto/$module directory by searching @INC | ||||
| 716 | |||||
| 717 | =item * | ||||
| 718 | |||||
| 719 | uses dl_findfile() to determine the filename to load | ||||
| 720 | |||||
| 721 | =item * | ||||
| 722 | |||||
| 723 | sets @dl_require_symbols to C<("boot_$module")> | ||||
| 724 | |||||
| 725 | =item * | ||||
| 726 | |||||
| 727 | executes an F<auto/$module/$module.bs> file if it exists | ||||
| 728 | (typically used to add to @dl_resolve_using any files which | ||||
| 729 | are required to load the module on the current platform) | ||||
| 730 | |||||
| 731 | =item * | ||||
| 732 | |||||
| 733 | calls dl_load_flags() to determine how to load the file. | ||||
| 734 | |||||
| 735 | =item * | ||||
| 736 | |||||
| 737 | calls dl_load_file() to load the file | ||||
| 738 | |||||
| 739 | =item * | ||||
| 740 | |||||
| 741 | calls dl_undef_symbols() and warns if any symbols are undefined | ||||
| 742 | |||||
| 743 | =item * | ||||
| 744 | |||||
| 745 | calls dl_find_symbol() for "boot_$module" | ||||
| 746 | |||||
| 747 | =item * | ||||
| 748 | |||||
| 749 | calls dl_install_xsub() to install it as "${module}::bootstrap" | ||||
| 750 | |||||
| 751 | =item * | ||||
| 752 | |||||
| 753 | calls &{"${module}::bootstrap"} to bootstrap the module (actually | ||||
| 754 | it uses the function reference returned by dl_install_xsub for speed) | ||||
| 755 | |||||
| 756 | =back | ||||
| 757 | |||||
| 758 | =back | ||||
| 759 | |||||
| 760 | |||||
| 761 | =head1 AUTHOR | ||||
| 762 | |||||
| 763 | Tim Bunce, 11 August 1994. | ||||
| 764 | |||||
| 765 | This interface is based on the work and comments of (in no particular | ||||
| 766 | order): Larry Wall, Robert Sanders, Dean Roehrich, Jeff Okamoto, Anno | ||||
| 767 | Siegel, Thomas Neumann, Paul Marquess, Charles Bailey, myself and others. | ||||
| 768 | |||||
| 769 | Larry Wall designed the elegant inherited bootstrap mechanism and | ||||
| 770 | implemented the first Perl 5 dynamic loader using it. | ||||
| 771 | |||||
| 772 | Solaris global loading added by Nick Ing-Simmons with design/coding | ||||
| 773 | assistance from Tim Bunce, January 1996. | ||||
| 774 | |||||
| 775 | =cut | ||||
# spent 139µs within DynaLoader::CORE:ftdir which was called 26 times, avg 5µs/call:
# 26 times (139µs+0s) by DynaLoader::bootstrap at line 158 of DynaLoader.pm, avg 5µs/call | |||||
# spent 90µs within DynaLoader::CORE:ftfile which was called 8 times, avg 11µs/call:
# 8 times (90µs+0s) by DynaLoader::bootstrap at line 162 of DynaLoader.pm, avg 11µs/call | |||||
# spent 54µs within DynaLoader::CORE:ftsize which was called 8 times, avg 7µs/call:
# 8 times (54µs+0s) by DynaLoader::bootstrap at line 183 of DynaLoader.pm, avg 7µs/call | |||||
# spent 309µs within DynaLoader::CORE:subst which was called 16 times, avg 19µs/call:
# 8 times (282µs+0s) by DynaLoader::bootstrap at line 182 of DynaLoader.pm, avg 35µs/call
# 8 times (27µs+0s) by DynaLoader::bootstrap at line 175 of DynaLoader.pm, avg 3µs/call | |||||
# spent 83µs within DynaLoader::dl_find_symbol which was called 16 times, avg 5µs/call:
# 8 times (62µs+0s) by DynaLoader::bootstrap at line 192 of DynaLoader.pm, avg 8µs/call
# 8 times (21µs+0s) by DynaLoader::bootstrap at line 215 of DynaLoader.pm, avg 3µs/call | |||||
# spent 56µs within DynaLoader::dl_install_xsub which was called 8 times, avg 7µs/call:
# 8 times (56µs+0s) by DynaLoader::bootstrap at line 220 of DynaLoader.pm, avg 7µs/call | |||||
# spent 20.3ms within DynaLoader::dl_load_file which was called 8 times, avg 2.53ms/call:
# 8 times (20.3ms+0s) by DynaLoader::bootstrap at line 204 of DynaLoader.pm, avg 2.53ms/call | |||||
# spent 17µs within DynaLoader::dl_undef_symbols which was called 8 times, avg 2µs/call:
# 8 times (17µs+0s) by DynaLoader::bootstrap at line 209 of DynaLoader.pm, avg 2µs/call |