venv/lib/python3.11/site-packages/setuptools/_distutils/command/build_ext.py

   1 """distutils.command.build_ext
   2
   3 Implements the Distutils 'build_ext' command, for building extension
   4 modules (currently limited to C extensions, should accommodate C++
   5 extensions ASAP)."""
   6
   7 import contextlib
   8 import os
   9 import re
  10 import sys
  11 from ..core import Command
  12 from ..errors import (
  13     DistutilsOptionError,
  14     DistutilsSetupError,
  15     CCompilerError,
  16     DistutilsError,
  17     CompileError,
  18     DistutilsPlatformError,
  19 )
  20 from ..sysconfig import customize_compiler, get_python_version
  21 from ..sysconfig import get_config_h_filename
  22 from ..dep_util import newer_group
  23 from ..extension import Extension
  24 from ..util import get_platform
  25 from distutils._log import log
  26 from . import py37compat
  27
  28 from site import USER_BASE
  29
  30 # An extension name is just a dot-separated list of Python NAMEs (ie.
  31 # the same as a fully-qualified module name).
  32 extension_name_re = re.compile(r'^[a-zA-Z_][a-zA-Z_0-9]*(\.[a-zA-Z_][a-zA-Z_0-9]*)*$')
  33
  34
  35 def show_compilers():
  36     from ..ccompiler import show_compilers
  37
  38     show_compilers()
  39
  40
  41 class build_ext(Command):
  42     description = "build C/C++ extensions (compile/link to build directory)"
  43
  44     # XXX thoughts on how to deal with complex command-line options like
  45     # these, i.e. how to make it so fancy_getopt can suck them off the
  46     # command line and make it look like setup.py defined the appropriate
  47     # lists of tuples of what-have-you.
  48     #   - each command needs a callback to process its command-line options
  49     #   - Command.__init__() needs access to its share of the whole
  50     #     command line (must ultimately come from
  51     #     Distribution.parse_command_line())
  52     #   - it then calls the current command class' option-parsing
  53     #     callback to deal with weird options like -D, which have to
  54     #     parse the option text and churn out some custom data
  55     #     structure
  56     #   - that data structure (in this case, a list of 2-tuples)
  57     #     will then be present in the command object by the time
  58     #     we get to finalize_options() (i.e. the constructor
  59     #     takes care of both command-line and client options
  60     #     in between initialize_options() and finalize_options())
  61
  62     sep_by = " (separated by '%s')" % os.pathsep
  63     user_options = [
  64         ('build-lib=', 'b', "directory for compiled extension modules"),
  65         ('build-temp=', 't', "directory for temporary files (build by-products)"),
  66         (
  67             'plat-name=',
  68             'p',
  69             "platform name to cross-compile for, if supported "
  70             "(default: %s)" % get_platform(),
  71         ),
  72         (
  73             'inplace',
  74             'i',
  75             "ignore build-lib and put compiled extensions into the source "
  76             + "directory alongside your pure Python modules",
  77         ),
  78         (
  79             'include-dirs=',
  80             'I',
  81             "list of directories to search for header files" + sep_by,
  82         ),
  83         ('define=', 'D', "C preprocessor macros to define"),
  84         ('undef=', 'U', "C preprocessor macros to undefine"),
  85         ('libraries=', 'l', "external C libraries to link with"),
  86         (
  87             'library-dirs=',
  88             'L',
  89             "directories to search for external C libraries" + sep_by,
  90         ),
  91         ('rpath=', 'R', "directories to search for shared C libraries at runtime"),
  92         ('link-objects=', 'O', "extra explicit link objects to include in the link"),
  93         ('debug', 'g', "compile/link with debugging information"),
  94         ('force', 'f', "forcibly build everything (ignore file timestamps)"),
  95         ('compiler=', 'c', "specify the compiler type"),
  96         ('parallel=', 'j', "number of parallel build jobs"),
  97         ('swig-cpp', None, "make SWIG create C++ files (default is C)"),
  98         ('swig-opts=', None, "list of SWIG command line options"),
  99         ('swig=', None, "path to the SWIG executable"),
 100         ('user', None, "add user include, library and rpath"),
 101     ]
 102
 103     boolean_options = ['inplace', 'debug', 'force', 'swig-cpp', 'user']
 104
 105     help_options = [
 106         ('help-compiler', None, "list available compilers", show_compilers),
 107     ]
 108
 109     def initialize_options(self):
 110         self.extensions = None
 111         self.build_lib = None
 112         self.plat_name = None
 113         self.build_temp = None
 114         self.inplace = 0
 115         self.package = None
 116
 117         self.include_dirs = None
 118         self.define = None
 119         self.undef = None
 120         self.libraries = None
 121         self.library_dirs = None
 122         self.rpath = None
 123         self.link_objects = None
 124         self.debug = None
 125         self.force = None
 126         self.compiler = None
 127         self.swig = None
 128         self.swig_cpp = None
 129         self.swig_opts = None
 130         self.user = None
 131         self.parallel = None
 132
 133     def finalize_options(self):  # noqa: C901
 134         from distutils import sysconfig
 135
 136         self.set_undefined_options(
 137             'build',
 138             ('build_lib', 'build_lib'),
 139             ('build_temp', 'build_temp'),
 140             ('compiler', 'compiler'),
 141             ('debug', 'debug'),
 142             ('force', 'force'),
 143             ('parallel', 'parallel'),
 144             ('plat_name', 'plat_name'),
 145         )
 146
 147         if self.package is None:
 148             self.package = self.distribution.ext_package
 149
 150         self.extensions = self.distribution.ext_modules
 151
 152         # Make sure Python's include directories (for Python.h, pyconfig.h,
 153         # etc.) are in the include search path.
 154         py_include = sysconfig.get_python_inc()
 155         plat_py_include = sysconfig.get_python_inc(plat_specific=1)
 156         if self.include_dirs is None:
 157             self.include_dirs = self.distribution.include_dirs or []
 158         if isinstance(self.include_dirs, str):
 159             self.include_dirs = self.include_dirs.split(os.pathsep)
 160
 161         # If in a virtualenv, add its include directory
 162         # Issue 16116
 163         if sys.exec_prefix != sys.base_exec_prefix:
 164             self.include_dirs.append(os.path.join(sys.exec_prefix, 'include'))
 165
 166         # Put the Python "system" include dir at the end, so that
 167         # any local include dirs take precedence.
 168         self.include_dirs.extend(py_include.split(os.path.pathsep))
 169         if plat_py_include != py_include:
 170             self.include_dirs.extend(plat_py_include.split(os.path.pathsep))
 171
 172         self.ensure_string_list('libraries')
 173         self.ensure_string_list('link_objects')
 174
 175         # Life is easier if we're not forever checking for None, so
 176         # simplify these options to empty lists if unset
 177         if self.libraries is None:
 178             self.libraries = []
 179         if self.library_dirs is None:
 180             self.library_dirs = []
 181         elif isinstance(self.library_dirs, str):
 182             self.library_dirs = self.library_dirs.split(os.pathsep)
 183
 184         if self.rpath is None:
 185             self.rpath = []
 186         elif isinstance(self.rpath, str):
 187             self.rpath = self.rpath.split(os.pathsep)
 188
 189         # for extensions under windows use different directories
 190         # for Release and Debug builds.
 191         # also Python's library directory must be appended to library_dirs
 192         if os.name == 'nt':
 193             # the 'libs' directory is for binary installs - we assume that
 194             # must be the *native* platform.  But we don't really support
 195             # cross-compiling via a binary install anyway, so we let it go.
 196             self.library_dirs.append(os.path.join(sys.exec_prefix, 'libs'))
 197             if sys.base_exec_prefix != sys.prefix:  # Issue 16116
 198                 self.library_dirs.append(os.path.join(sys.base_exec_prefix, 'libs'))
 199             if self.debug:
 200                 self.build_temp = os.path.join(self.build_temp, "Debug")
 201             else:
 202                 self.build_temp = os.path.join(self.build_temp, "Release")
 203
 204             # Append the source distribution include and library directories,
 205             # this allows distutils on windows to work in the source tree
 206             self.include_dirs.append(os.path.dirname(get_config_h_filename()))
 207             self.library_dirs.append(sys.base_exec_prefix)
 208
 209             # Use the .lib files for the correct architecture
 210             if self.plat_name == 'win32':
 211                 suffix = 'win32'
 212             else:
 213                 # win-amd64
 214                 suffix = self.plat_name[4:]
 215             new_lib = os.path.join(sys.exec_prefix, 'PCbuild')
 216             if suffix:
 217                 new_lib = os.path.join(new_lib, suffix)
 218             self.library_dirs.append(new_lib)
 219
 220         # For extensions under Cygwin, Python's library directory must be
 221         # appended to library_dirs
 222         if sys.platform[:6] == 'cygwin':
 223             if not sysconfig.python_build:
 224                 # building third party extensions
 225                 self.library_dirs.append(
 226                     os.path.join(
 227                         sys.prefix, "lib", "python" + get_python_version(), "config"
 228                     )
 229                 )
 230             else:
 231                 # building python standard extensions
 232                 self.library_dirs.append('.')
 233
 234         # For building extensions with a shared Python library,
 235         # Python's library directory must be appended to library_dirs
 236         # See Issues: #1600860, #4366
 237         if sysconfig.get_config_var('Py_ENABLE_SHARED'):
 238             if not sysconfig.python_build:
 239                 # building third party extensions
 240                 self.library_dirs.append(sysconfig.get_config_var('LIBDIR'))
 241             else:
 242                 # building python standard extensions
 243                 self.library_dirs.append('.')
 244
 245         # The argument parsing will result in self.define being a string, but
 246         # it has to be a list of 2-tuples.  All the preprocessor symbols
 247         # specified by the 'define' option will be set to '1'.  Multiple
 248         # symbols can be separated with commas.
 249
 250         if self.define:
 251             defines = self.define.split(',')
 252             self.define = [(symbol, '1') for symbol in defines]
 253
 254         # The option for macros to undefine is also a string from the
 255         # option parsing, but has to be a list.  Multiple symbols can also
 256         # be separated with commas here.
 257         if self.undef:
 258             self.undef = self.undef.split(',')
 259
 260         if self.swig_opts is None:
 261             self.swig_opts = []
 262         else:
 263             self.swig_opts = self.swig_opts.split(' ')
 264
 265         # Finally add the user include and library directories if requested
 266         if self.user:
 267             user_include = os.path.join(USER_BASE, "include")
 268             user_lib = os.path.join(USER_BASE, "lib")
 269             if os.path.isdir(user_include):
 270                 self.include_dirs.append(user_include)
 271             if os.path.isdir(user_lib):
 272                 self.library_dirs.append(user_lib)
 273                 self.rpath.append(user_lib)
 274
 275         if isinstance(self.parallel, str):
 276             try:
 277                 self.parallel = int(self.parallel)
 278             except ValueError:
 279                 raise DistutilsOptionError("parallel should be an integer")
 280
 281     def run(self):  # noqa: C901
 282         from ..ccompiler import new_compiler
 283
 284         # 'self.extensions', as supplied by setup.py, is a list of
 285         # Extension instances.  See the documentation for Extension (in
 286         # distutils.extension) for details.
 287         #
 288         # For backwards compatibility with Distutils 0.8.2 and earlier, we
 289         # also allow the 'extensions' list to be a list of tuples:
 290         #    (ext_name, build_info)
 291         # where build_info is a dictionary containing everything that
 292         # Extension instances do except the name, with a few things being
 293         # differently named.  We convert these 2-tuples to Extension
 294         # instances as needed.
 295
 296         if not self.extensions:
 297             return
 298
 299         # If we were asked to build any C/C++ libraries, make sure that the
 300         # directory where we put them is in the library search path for
 301         # linking extensions.
 302         if self.distribution.has_c_libraries():
 303             build_clib = self.get_finalized_command('build_clib')
 304             self.libraries.extend(build_clib.get_library_names() or [])
 305             self.library_dirs.append(build_clib.build_clib)
 306
 307         # Setup the CCompiler object that we'll use to do all the
 308         # compiling and linking
 309         self.compiler = new_compiler(
 310             compiler=self.compiler,
 311             verbose=self.verbose,
 312             dry_run=self.dry_run,
 313             force=self.force,
 314         )
 315         customize_compiler(self.compiler)
 316         # If we are cross-compiling, init the compiler now (if we are not
 317         # cross-compiling, init would not hurt, but people may rely on
 318         # late initialization of compiler even if they shouldn't...)
 319         if os.name == 'nt' and self.plat_name != get_platform():
 320             self.compiler.initialize(self.plat_name)
 321
 322         # And make sure that any compile/link-related options (which might
 323         # come from the command-line or from the setup script) are set in
 324         # that CCompiler object -- that way, they automatically apply to
 325         # all compiling and linking done here.
 326         if self.include_dirs is not None:
 327             self.compiler.set_include_dirs(self.include_dirs)
 328         if self.define is not None:
 329             # 'define' option is a list of (name,value) tuples
 330             for name, value in self.define:
 331                 self.compiler.define_macro(name, value)
 332         if self.undef is not None:
 333             for macro in self.undef:
 334                 self.compiler.undefine_macro(macro)
 335         if self.libraries is not None:
 336             self.compiler.set_libraries(self.libraries)
 337         if self.library_dirs is not None:
 338             self.compiler.set_library_dirs(self.library_dirs)
 339         if self.rpath is not None:
 340             self.compiler.set_runtime_library_dirs(self.rpath)
 341         if self.link_objects is not None:
 342             self.compiler.set_link_objects(self.link_objects)
 343
 344         # Now actually compile and link everything.
 345         self.build_extensions()
 346
 347     def check_extensions_list(self, extensions):  # noqa: C901
 348         """Ensure that the list of extensions (presumably provided as a
 349         command option 'extensions') is valid, i.e. it is a list of
 350         Extension objects.  We also support the old-style list of 2-tuples,
 351         where the tuples are (ext_name, build_info), which are converted to
 352         Extension instances here.
 353
 354         Raise DistutilsSetupError if the structure is invalid anywhere;
 355         just returns otherwise.
 356         """
 357         if not isinstance(extensions, list):
 358             raise DistutilsSetupError(
 359                 "'ext_modules' option must be a list of Extension instances"
 360             )
 361
 362         for i, ext in enumerate(extensions):
 363             if isinstance(ext, Extension):
 364                 continue  # OK! (assume type-checking done
 365                 # by Extension constructor)
 366
 367             if not isinstance(ext, tuple) or len(ext) != 2:
 368                 raise DistutilsSetupError(
 369                     "each element of 'ext_modules' option must be an "
 370                     "Extension instance or 2-tuple"
 371                 )
 372
 373             ext_name, build_info = ext
 374
 375             log.warning(
 376                 "old-style (ext_name, build_info) tuple found in "
 377                 "ext_modules for extension '%s' "
 378                 "-- please convert to Extension instance",
 379                 ext_name,
 380             )
 381
 382             if not (isinstance(ext_name, str) and extension_name_re.match(ext_name)):
 383                 raise DistutilsSetupError(
 384                     "first element of each tuple in 'ext_modules' "
 385                     "must be the extension name (a string)"
 386                 )
 387
 388             if not isinstance(build_info, dict):
 389                 raise DistutilsSetupError(
 390                     "second element of each tuple in 'ext_modules' "
 391                     "must be a dictionary (build info)"
 392                 )
 393
 394             # OK, the (ext_name, build_info) dict is type-safe: convert it
 395             # to an Extension instance.
 396             ext = Extension(ext_name, build_info['sources'])
 397
 398             # Easy stuff: one-to-one mapping from dict elements to
 399             # instance attributes.
 400             for key in (
 401                 'include_dirs',
 402                 'library_dirs',
 403                 'libraries',
 404                 'extra_objects',
 405                 'extra_compile_args',
 406                 'extra_link_args',
 407             ):
 408                 val = build_info.get(key)
 409                 if val is not None:
 410                     setattr(ext, key, val)
 411
 412             # Medium-easy stuff: same syntax/semantics, different names.
 413             ext.runtime_library_dirs = build_info.get('rpath')
 414             if 'def_file' in build_info:
 415                 log.warning(
 416                     "'def_file' element of build info dict " "no longer supported"
 417                 )
 418
 419             # Non-trivial stuff: 'macros' split into 'define_macros'
 420             # and 'undef_macros'.
 421             macros = build_info.get('macros')
 422             if macros:
 423                 ext.define_macros = []
 424                 ext.undef_macros = []
 425                 for macro in macros:
 426                     if not (isinstance(macro, tuple) and len(macro) in (1, 2)):
 427                         raise DistutilsSetupError(
 428                             "'macros' element of build info dict "
 429                             "must be 1- or 2-tuple"
 430                         )
 431                     if len(macro) == 1:
 432                         ext.undef_macros.append(macro[0])
 433                     elif len(macro) == 2:
 434                         ext.define_macros.append(macro)
 435
 436             extensions[i] = ext
 437
 438     def get_source_files(self):
 439         self.check_extensions_list(self.extensions)
 440         filenames = []
 441
 442         # Wouldn't it be neat if we knew the names of header files too...
 443         for ext in self.extensions:
 444             filenames.extend(ext.sources)
 445         return filenames
 446
 447     def get_outputs(self):
 448         # Sanity check the 'extensions' list -- can't assume this is being
 449         # done in the same run as a 'build_extensions()' call (in fact, we
 450         # can probably assume that it *isn't*!).
 451         self.check_extensions_list(self.extensions)
 452
 453         # And build the list of output (built) filenames.  Note that this
 454         # ignores the 'inplace' flag, and assumes everything goes in the
 455         # "build" tree.
 456         outputs = []
 457         for ext in self.extensions:
 458             outputs.append(self.get_ext_fullpath(ext.name))
 459         return outputs
 460
 461     def build_extensions(self):
 462         # First, sanity-check the 'extensions' list
 463         self.check_extensions_list(self.extensions)
 464         if self.parallel:
 465             self._build_extensions_parallel()
 466         else:
 467             self._build_extensions_serial()
 468
 469     def _build_extensions_parallel(self):
 470         workers = self.parallel
 471         if self.parallel is True:
 472             workers = os.cpu_count()  # may return None
 473         try:
 474             from concurrent.futures import ThreadPoolExecutor
 475         except ImportError:
 476             workers = None
 477
 478         if workers is None:
 479             self._build_extensions_serial()
 480             return
 481
 482         with ThreadPoolExecutor(max_workers=workers) as executor:
 483             futures = [
 484                 executor.submit(self.build_extension, ext) for ext in self.extensions
 485             ]
 486             for ext, fut in zip(self.extensions, futures):
 487                 with self._filter_build_errors(ext):
 488                     fut.result()
 489
 490     def _build_extensions_serial(self):
 491         for ext in self.extensions:
 492             with self._filter_build_errors(ext):
 493                 self.build_extension(ext)
 494
 495     @contextlib.contextmanager
 496     def _filter_build_errors(self, ext):
 497         try:
 498             yield
 499         except (CCompilerError, DistutilsError, CompileError) as e:
 500             if not ext.optional:
 501                 raise
 502             self.warn('building extension "{}" failed: {}'.format(ext.name, e))
 503
 504     def build_extension(self, ext):
 505         sources = ext.sources
 506         if sources is None or not isinstance(sources, (list, tuple)):
 507             raise DistutilsSetupError(
 508                 "in 'ext_modules' option (extension '%s'), "
 509                 "'sources' must be present and must be "
 510                 "a list of source filenames" % ext.name
 511             )
 512         # sort to make the resulting .so file build reproducible
 513         sources = sorted(sources)
 514
 515         ext_path = self.get_ext_fullpath(ext.name)
 516         depends = sources + ext.depends
 517         if not (self.force or newer_group(depends, ext_path, 'newer')):
 518             log.debug("skipping '%s' extension (up-to-date)", ext.name)
 519             return
 520         else:
 521             log.info("building '%s' extension", ext.name)
 522
 523         # First, scan the sources for SWIG definition files (.i), run
 524         # SWIG on 'em to create .c files, and modify the sources list
 525         # accordingly.
 526         sources = self.swig_sources(sources, ext)
 527
 528         # Next, compile the source code to object files.
 529
 530         # XXX not honouring 'define_macros' or 'undef_macros' -- the
 531         # CCompiler API needs to change to accommodate this, and I
 532         # want to do one thing at a time!
 533
 534         # Two possible sources for extra compiler arguments:
 535         #   - 'extra_compile_args' in Extension object
 536         #   - CFLAGS environment variable (not particularly
 537         #     elegant, but people seem to expect it and I
 538         #     guess it's useful)
 539         # The environment variable should take precedence, and
 540         # any sensible compiler will give precedence to later
 541         # command line args.  Hence we combine them in order:
 542         extra_args = ext.extra_compile_args or []
 543
 544         macros = ext.define_macros[:]
 545         for undef in ext.undef_macros:
 546             macros.append((undef,))
 547
 548         objects = self.compiler.compile(
 549             sources,
 550             output_dir=self.build_temp,
 551             macros=macros,
 552             include_dirs=ext.include_dirs,
 553             debug=self.debug,
 554             extra_postargs=extra_args,
 555             depends=ext.depends,
 556         )
 557
 558         # XXX outdated variable, kept here in case third-part code
 559         # needs it.
 560         self._built_objects = objects[:]
 561
 562         # Now link the object files together into a "shared object" --
 563         # of course, first we have to figure out all the other things
 564         # that go into the mix.
 565         if ext.extra_objects:
 566             objects.extend(ext.extra_objects)
 567         extra_args = ext.extra_link_args or []
 568
 569         # Detect target language, if not provided
 570         language = ext.language or self.compiler.detect_language(sources)
 571
 572         self.compiler.link_shared_object(
 573             objects,
 574             ext_path,
 575             libraries=self.get_libraries(ext),
 576             library_dirs=ext.library_dirs,
 577             runtime_library_dirs=ext.runtime_library_dirs,
 578             extra_postargs=extra_args,
 579             export_symbols=self.get_export_symbols(ext),
 580             debug=self.debug,
 581             build_temp=self.build_temp,
 582             target_lang=language,
 583         )
 584
 585     def swig_sources(self, sources, extension):
 586         """Walk the list of source files in 'sources', looking for SWIG
 587         interface (.i) files.  Run SWIG on all that are found, and
 588         return a modified 'sources' list with SWIG source files replaced
 589         by the generated C (or C++) files.
 590         """
 591         new_sources = []
 592         swig_sources = []
 593         swig_targets = {}
 594
 595         # XXX this drops generated C/C++ files into the source tree, which
 596         # is fine for developers who want to distribute the generated
 597         # source -- but there should be an option to put SWIG output in
 598         # the temp dir.
 599
 600         if self.swig_cpp:
 601             log.warning("--swig-cpp is deprecated - use --swig-opts=-c++")
 602
 603         if (
 604             self.swig_cpp
 605             or ('-c++' in self.swig_opts)
 606             or ('-c++' in extension.swig_opts)
 607         ):
 608             target_ext = '.cpp'
 609         else:
 610             target_ext = '.c'
 611
 612         for source in sources:
 613             (base, ext) = os.path.splitext(source)
 614             if ext == ".i":  # SWIG interface file
 615                 new_sources.append(base + '_wrap' + target_ext)
 616                 swig_sources.append(source)
 617                 swig_targets[source] = new_sources[-1]
 618             else:
 619                 new_sources.append(source)
 620
 621         if not swig_sources:
 622             return new_sources
 623
 624         swig = self.swig or self.find_swig()
 625         swig_cmd = [swig, "-python"]
 626         swig_cmd.extend(self.swig_opts)
 627         if self.swig_cpp:
 628             swig_cmd.append("-c++")
 629
 630         # Do not override commandline arguments
 631         if not self.swig_opts:
 632             for o in extension.swig_opts:
 633                 swig_cmd.append(o)
 634
 635         for source in swig_sources:
 636             target = swig_targets[source]
 637             log.info("swigging %s to %s", source, target)
 638             self.spawn(swig_cmd + ["-o", target, source])
 639
 640         return new_sources
 641
 642     def find_swig(self):
 643         """Return the name of the SWIG executable.  On Unix, this is
 644         just "swig" -- it should be in the PATH.  Tries a bit harder on
 645         Windows.
 646         """
 647         if os.name == "posix":
 648             return "swig"
 649         elif os.name == "nt":
 650             # Look for SWIG in its standard installation directory on
 651             # Windows (or so I presume!).  If we find it there, great;
 652             # if not, act like Unix and assume it's in the PATH.
 653             for vers in ("1.3", "1.2", "1.1"):
 654                 fn = os.path.join("c:\\swig%s" % vers, "swig.exe")
 655                 if os.path.isfile(fn):
 656                     return fn
 657             else:
 658                 return "swig.exe"
 659         else:
 660             raise DistutilsPlatformError(
 661                 "I don't know how to find (much less run) SWIG "
 662                 "on platform '%s'" % os.name
 663             )
 664
 665     # -- Name generators -----------------------------------------------
 666     # (extension names, filenames, whatever)
 667     def get_ext_fullpath(self, ext_name):
 668         """Returns the path of the filename for a given extension.
 669
 670         The file is located in `build_lib` or directly in the package
 671         (inplace option).
 672         """
 673         fullname = self.get_ext_fullname(ext_name)
 674         modpath = fullname.split('.')
 675         filename = self.get_ext_filename(modpath[-1])
 676
 677         if not self.inplace:
 678             # no further work needed
 679             # returning :
 680             #   build_dir/package/path/filename
 681             filename = os.path.join(*modpath[:-1] + [filename])
 682             return os.path.join(self.build_lib, filename)
 683
 684         # the inplace option requires to find the package directory
 685         # using the build_py command for that
 686         package = '.'.join(modpath[0:-1])
 687         build_py = self.get_finalized_command('build_py')
 688         package_dir = os.path.abspath(build_py.get_package_dir(package))
 689
 690         # returning
 691         #   package_dir/filename
 692         return os.path.join(package_dir, filename)
 693
 694     def get_ext_fullname(self, ext_name):
 695         """Returns the fullname of a given extension name.
 696
 697         Adds the `package.` prefix"""
 698         if self.package is None:
 699             return ext_name
 700         else:
 701             return self.package + '.' + ext_name
 702
 703     def get_ext_filename(self, ext_name):
 704         r"""Convert the name of an extension (eg. "foo.bar") into the name
 705         of the file from which it will be loaded (eg. "foo/bar.so", or
 706         "foo\bar.pyd").
 707         """
 708         from ..sysconfig import get_config_var
 709
 710         ext_path = ext_name.split('.')
 711         ext_suffix = get_config_var('EXT_SUFFIX')
 712         return os.path.join(*ext_path) + ext_suffix
 713
 714     def get_export_symbols(self, ext):
 715         """Return the list of symbols that a shared extension has to
 716         export.  This either uses 'ext.export_symbols' or, if it's not
 717         provided, "PyInit_" + module_name.  Only relevant on Windows, where
 718         the .pyd file (DLL) must export the module "PyInit_" function.
 719         """
 720         name = ext.name.split('.')[-1]
 721         try:
 722             # Unicode module name support as defined in PEP-489
 723             # https://peps.python.org/pep-0489/#export-hook-name
 724             name.encode('ascii')
 725         except UnicodeEncodeError:
 726             suffix = 'U_' + name.encode('punycode').replace(b'-', b'_').decode('ascii')
 727         else:
 728             suffix = "_" + name
 729
 730         initfunc_name = "PyInit" + suffix
 731         if initfunc_name not in ext.export_symbols:
 732             ext.export_symbols.append(initfunc_name)
 733         return ext.export_symbols
 734
 735     def get_libraries(self, ext):  # noqa: C901
 736         """Return the list of libraries to link against when building a
 737         shared extension.  On most platforms, this is just 'ext.libraries';
 738         on Windows, we add the Python library (eg. python20.dll).
 739         """
 740         # The python library is always needed on Windows.  For MSVC, this
 741         # is redundant, since the library is mentioned in a pragma in
 742         # pyconfig.h that MSVC groks.  The other Windows compilers all seem
 743         # to need it mentioned explicitly, though, so that's what we do.
 744         # Append '_d' to the python import library on debug builds.
 745         if sys.platform == "win32":
 746             from .._msvccompiler import MSVCCompiler
 747
 748             if not isinstance(self.compiler, MSVCCompiler):
 749                 template = "python%d%d"
 750                 if self.debug:
 751                     template = template + '_d'
 752                 pythonlib = template % (
 753                     sys.hexversion >> 24,
 754                     (sys.hexversion >> 16) & 0xFF,
 755                 )
 756                 # don't extend ext.libraries, it may be shared with other
 757                 # extensions, it is a reference to the original list
 758                 return ext.libraries + [pythonlib]
 759         else:
 760             # On Android only the main executable and LD_PRELOADs are considered
 761             # to be RTLD_GLOBAL, all the dependencies of the main executable
 762             # remain RTLD_LOCAL and so the shared libraries must be linked with
 763             # libpython when python is built with a shared python library (issue
 764             # bpo-21536).
 765             # On Cygwin (and if required, other POSIX-like platforms based on
 766             # Windows like MinGW) it is simply necessary that all symbols in
 767             # shared libraries are resolved at link time.
 768             from ..sysconfig import get_config_var
 769
 770             link_libpython = False
 771             if get_config_var('Py_ENABLE_SHARED'):
 772                 # A native build on an Android device or on Cygwin
 773                 if hasattr(sys, 'getandroidapilevel'):
 774                     link_libpython = True
 775                 elif sys.platform == 'cygwin':
 776                     link_libpython = True
 777                 elif '_PYTHON_HOST_PLATFORM' in os.environ:
 778                     # We are cross-compiling for one of the relevant platforms
 779                     if get_config_var('ANDROID_API_LEVEL') != 0:
 780                         link_libpython = True
 781                     elif get_config_var('MACHDEP') == 'cygwin':
 782                         link_libpython = True
 783
 784             if link_libpython:
 785                 ldversion = get_config_var('LDVERSION')
 786                 return ext.libraries + ['python' + ldversion]
 787
 788         return ext.libraries + py37compat.pythonlib()