1"""Provide access to Python's configuration information.  The specific
2configuration variables available depend heavily on the platform and
3configuration.  The values may be retrieved using
4get_config_var(name), and the list of variables is available via
5get_config_vars().keys().  Additional convenience functions are also
6available.
7
8Written by:   Fred L. Drake, Jr.
9Email:        <fdrake@acm.org>
10"""
11
12import _imp
13import os
14import re
15import sys
16
17from .errors import DistutilsPlatformError
18
19# These are needed in a couple of spots, so just compute them once.
20PREFIX = os.path.normpath(sys.prefix)
21EXEC_PREFIX = os.path.normpath(sys.exec_prefix)
22BASE_PREFIX = os.path.normpath(sys.base_prefix)
23BASE_EXEC_PREFIX = os.path.normpath(sys.base_exec_prefix)
24
25# Path to the base directory of the project. On Windows the binary may
26# live in project/PCbuild/win32 or project/PCbuild/amd64.
27# set for cross builds
28if "_PYTHON_PROJECT_BASE" in os.environ:
29    project_base = os.path.abspath(os.environ["_PYTHON_PROJECT_BASE"])
30else:
31    project_base = os.path.dirname(os.path.abspath(sys.executable))
32
33
34# python_build: (Boolean) if true, we're either building Python or
35# building an extension with an un-installed Python, so we use
36# different (hard-wired) directories.
37# Setup.local is available for Makefile builds including VPATH builds,
38# Setup.dist is available on Windows
39def _is_python_source_dir(d):
40    for fn in ("Setup.dist", "Setup.local"):
41        if os.path.isfile(os.path.join(d, "Modules", fn)):
42            return True
43    return False
44
45_sys_home = getattr(sys, '_home', None)
46
47if os.name == 'nt':
48    def _fix_pcbuild(d):
49        if d and os.path.normcase(d).startswith(
50                os.path.normcase(os.path.join(PREFIX, "PCbuild"))):
51            return PREFIX
52        return d
53    project_base = _fix_pcbuild(project_base)
54    _sys_home = _fix_pcbuild(_sys_home)
55
56def _python_build():
57    if _sys_home:
58        return _is_python_source_dir(_sys_home)
59    return _is_python_source_dir(project_base)
60
61python_build = _python_build()
62
63
64# Calculate the build qualifier flags if they are defined.  Adding the flags
65# to the include and lib directories only makes sense for an installation, not
66# an in-source build.
67build_flags = ''
68try:
69    if not python_build:
70        build_flags = sys.abiflags
71except AttributeError:
72    # It's not a configure-based build, so the sys module doesn't have
73    # this attribute, which is fine.
74    pass
75
76def get_python_version():
77    """Return a string containing the major and minor Python version,
78    leaving off the patchlevel.  Sample return values could be '1.5'
79    or '2.2'.
80    """
81    return '%d.%d' % sys.version_info[:2]
82
83
84def get_python_inc(plat_specific=0, prefix=None):
85    """Return the directory containing installed Python header files.
86
87    If 'plat_specific' is false (the default), this is the path to the
88    non-platform-specific header files, i.e. Python.h and so on;
89    otherwise, this is the path to platform-specific header files
90    (namely pyconfig.h).
91
92    If 'prefix' is supplied, use it instead of sys.base_prefix or
93    sys.base_exec_prefix -- i.e., ignore 'plat_specific'.
94    """
95    if prefix is None:
96        prefix = plat_specific and BASE_EXEC_PREFIX or BASE_PREFIX
97    if os.name == "posix":
98        if python_build:
99            # Assume the executable is in the build directory.  The
100            # pyconfig.h file should be in the same directory.  Since
101            # the build directory may not be the source directory, we
102            # must use "srcdir" from the makefile to find the "Include"
103            # directory.
104            if plat_specific:
105                return _sys_home or project_base
106            else:
107                incdir = os.path.join(get_config_var('srcdir'), 'Include')
108                return os.path.normpath(incdir)
109        python_dir = 'python' + get_python_version() + build_flags
110        return os.path.join(prefix, "include", python_dir)
111    elif os.name == "nt":
112        if python_build:
113            # Include both the include and PC dir to ensure we can find
114            # pyconfig.h
115            return (os.path.join(prefix, "include") + os.path.pathsep +
116                    os.path.join(prefix, "PC"))
117        return os.path.join(prefix, "include")
118    else:
119        raise DistutilsPlatformError(
120            "I don't know where Python installs its C header files "
121            "on platform '%s'" % os.name)
122
123
124def get_python_lib(plat_specific=0, standard_lib=0, prefix=None):
125    """Return the directory containing the Python library (standard or
126    site additions).
127
128    If 'plat_specific' is true, return the directory containing
129    platform-specific modules, i.e. any module from a non-pure-Python
130    module distribution; otherwise, return the platform-shared library
131    directory.  If 'standard_lib' is true, return the directory
132    containing standard Python library modules; otherwise, return the
133    directory for site-specific modules.
134
135    If 'prefix' is supplied, use it instead of sys.base_prefix or
136    sys.base_exec_prefix -- i.e., ignore 'plat_specific'.
137    """
138    if prefix is None:
139        if standard_lib:
140            prefix = plat_specific and BASE_EXEC_PREFIX or BASE_PREFIX
141        else:
142            prefix = plat_specific and EXEC_PREFIX or PREFIX
143
144    if os.name == "posix":
145        libpython = os.path.join(prefix,
146                                 "lib", "python" + get_python_version())
147        if standard_lib:
148            return libpython
149        else:
150            return os.path.join(libpython, "site-packages")
151    elif os.name == "nt":
152        if standard_lib:
153            return os.path.join(prefix, "Lib")
154        else:
155            return os.path.join(prefix, "Lib", "site-packages")
156    else:
157        raise DistutilsPlatformError(
158            "I don't know where Python installs its library "
159            "on platform '%s'" % os.name)
160
161
162
163def customize_compiler(compiler):
164    """Do any platform-specific customization of a CCompiler instance.
165
166    Mainly needed on Unix, so we can plug in the information that
167    varies across Unices and is stored in Python's Makefile.
168    """
169    if compiler.compiler_type == "unix":
170        if sys.platform == "darwin":
171            # Perform first-time customization of compiler-related
172            # config vars on OS X now that we know we need a compiler.
173            # This is primarily to support Pythons from binary
174            # installers.  The kind and paths to build tools on
175            # the user system may vary significantly from the system
176            # that Python itself was built on.  Also the user OS
177            # version and build tools may not support the same set
178            # of CPU architectures for universal builds.
179            global _config_vars
180            # Use get_config_var() to ensure _config_vars is initialized.
181            if not get_config_var('CUSTOMIZED_OSX_COMPILER'):
182                import _osx_support
183                _osx_support.customize_compiler(_config_vars)
184                _config_vars['CUSTOMIZED_OSX_COMPILER'] = 'True'
185
186        (cc, cxx, opt, cflags, ccshared, ldshared, shlib_suffix, ar, ar_flags) = \
187            get_config_vars('CC', 'CXX', 'OPT', 'CFLAGS',
188                            'CCSHARED', 'LDSHARED', 'SHLIB_SUFFIX', 'AR', 'ARFLAGS')
189
190        if 'CC' in os.environ:
191            newcc = os.environ['CC']
192            if (sys.platform == 'darwin'
193                    and 'LDSHARED' not in os.environ
194                    and ldshared.startswith(cc)):
195                # On OS X, if CC is overridden, use that as the default
196                #       command for LDSHARED as well
197                ldshared = newcc + ldshared[len(cc):]
198            cc = newcc
199        if 'CXX' in os.environ:
200            cxx = os.environ['CXX']
201        if 'LDSHARED' in os.environ:
202            ldshared = os.environ['LDSHARED']
203        if 'CPP' in os.environ:
204            cpp = os.environ['CPP']
205        else:
206            cpp = cc + " -E"           # not always
207        if 'LDFLAGS' in os.environ:
208            ldshared = ldshared + ' ' + os.environ['LDFLAGS']
209        if 'CFLAGS' in os.environ:
210            cflags = opt + ' ' + os.environ['CFLAGS']
211            ldshared = ldshared + ' ' + os.environ['CFLAGS']
212        if 'CPPFLAGS' in os.environ:
213            cpp = cpp + ' ' + os.environ['CPPFLAGS']
214            cflags = cflags + ' ' + os.environ['CPPFLAGS']
215            ldshared = ldshared + ' ' + os.environ['CPPFLAGS']
216        if 'AR' in os.environ:
217            ar = os.environ['AR']
218        if 'ARFLAGS' in os.environ:
219            archiver = ar + ' ' + os.environ['ARFLAGS']
220        else:
221            archiver = ar + ' ' + ar_flags
222
223        cc_cmd = cc + ' ' + cflags
224        compiler.set_executables(
225            preprocessor=cpp,
226            compiler=cc_cmd,
227            compiler_so=cc_cmd + ' ' + ccshared,
228            compiler_cxx=cxx,
229            linker_so=ldshared,
230            linker_exe=cc,
231            archiver=archiver)
232
233        compiler.shared_lib_extension = shlib_suffix
234
235
236def get_config_h_filename():
237    """Return full pathname of installed pyconfig.h file."""
238    if python_build:
239        if os.name == "nt":
240            inc_dir = os.path.join(_sys_home or project_base, "PC")
241        else:
242            inc_dir = _sys_home or project_base
243    else:
244        inc_dir = get_python_inc(plat_specific=1)
245
246    return os.path.join(inc_dir, 'pyconfig.h')
247
248
249def get_makefile_filename():
250    """Return full pathname of installed Makefile from the Python build."""
251    if python_build:
252        return os.path.join(_sys_home or project_base, "Makefile")
253    lib_dir = get_python_lib(plat_specific=0, standard_lib=1)
254    config_file = 'config-{}{}'.format(get_python_version(), build_flags)
255    if hasattr(sys.implementation, '_multiarch'):
256        config_file += '-%s' % sys.implementation._multiarch
257    return os.path.join(lib_dir, config_file, 'Makefile')
258
259
260def parse_config_h(fp, g=None):
261    """Parse a config.h-style file.
262
263    A dictionary containing name/value pairs is returned.  If an
264    optional dictionary is passed in as the second argument, it is
265    used instead of a new dictionary.
266    """
267    if g is None:
268        g = {}
269    define_rx = re.compile("#define ([A-Z][A-Za-z0-9_]+) (.*)\n")
270    undef_rx = re.compile("/[*] #undef ([A-Z][A-Za-z0-9_]+) [*]/\n")
271    #
272    while True:
273        line = fp.readline()
274        if not line:
275            break
276        m = define_rx.match(line)
277        if m:
278            n, v = m.group(1, 2)
279            try: v = int(v)
280            except ValueError: pass
281            g[n] = v
282        else:
283            m = undef_rx.match(line)
284            if m:
285                g[m.group(1)] = 0
286    return g
287
288
289# Regexes needed for parsing Makefile (and similar syntaxes,
290# like old-style Setup files).
291_variable_rx = re.compile(r"([a-zA-Z][a-zA-Z0-9_]+)\s*=\s*(.*)")
292_findvar1_rx = re.compile(r"\$\(([A-Za-z][A-Za-z0-9_]*)\)")
293_findvar2_rx = re.compile(r"\${([A-Za-z][A-Za-z0-9_]*)}")
294
295def parse_makefile(fn, g=None):
296    """Parse a Makefile-style file.
297
298    A dictionary containing name/value pairs is returned.  If an
299    optional dictionary is passed in as the second argument, it is
300    used instead of a new dictionary.
301    """
302    from distutils.text_file import TextFile
303    fp = TextFile(fn, strip_comments=1, skip_blanks=1, join_lines=1, errors="surrogateescape")
304
305    if g is None:
306        g = {}
307    done = {}
308    notdone = {}
309
310    while True:
311        line = fp.readline()
312        if line is None: # eof
313            break
314        m = _variable_rx.match(line)
315        if m:
316            n, v = m.group(1, 2)
317            v = v.strip()
318            # `$$' is a literal `$' in make
319            tmpv = v.replace('$$', '')
320
321            if "$" in tmpv:
322                notdone[n] = v
323            else:
324                try:
325                    v = int(v)
326                except ValueError:
327                    # insert literal `$'
328                    done[n] = v.replace('$$', '$')
329                else:
330                    done[n] = v
331
332    # Variables with a 'PY_' prefix in the makefile. These need to
333    # be made available without that prefix through sysconfig.
334    # Special care is needed to ensure that variable expansion works, even
335    # if the expansion uses the name without a prefix.
336    renamed_variables = ('CFLAGS', 'LDFLAGS', 'CPPFLAGS')
337
338    # do variable interpolation here
339    while notdone:
340        for name in list(notdone):
341            value = notdone[name]
342            m = _findvar1_rx.search(value) or _findvar2_rx.search(value)
343            if m:
344                n = m.group(1)
345                found = True
346                if n in done:
347                    item = str(done[n])
348                elif n in notdone:
349                    # get it on a subsequent round
350                    found = False
351                elif n in os.environ:
352                    # do it like make: fall back to environment
353                    item = os.environ[n]
354
355                elif n in renamed_variables:
356                    if name.startswith('PY_') and name[3:] in renamed_variables:
357                        item = ""
358
359                    elif 'PY_' + n in notdone:
360                        found = False
361
362                    else:
363                        item = str(done['PY_' + n])
364                else:
365                    done[n] = item = ""
366                if found:
367                    after = value[m.end():]
368                    value = value[:m.start()] + item + after
369                    if "$" in after:
370                        notdone[name] = value
371                    else:
372                        try: value = int(value)
373                        except ValueError:
374                            done[name] = value.strip()
375                        else:
376                            done[name] = value
377                        del notdone[name]
378
379                        if name.startswith('PY_') \
380                            and name[3:] in renamed_variables:
381
382                            name = name[3:]
383                            if name not in done:
384                                done[name] = value
385            else:
386                # bogus variable reference; just drop it since we can't deal
387                del notdone[name]
388
389    fp.close()
390
391    # strip spurious spaces
392    for k, v in done.items():
393        if isinstance(v, str):
394            done[k] = v.strip()
395
396    # save the results in the global dictionary
397    g.update(done)
398    return g
399
400
401def expand_makefile_vars(s, vars):
402    """Expand Makefile-style variables -- "${foo}" or "$(foo)" -- in
403    'string' according to 'vars' (a dictionary mapping variable names to
404    values).  Variables not present in 'vars' are silently expanded to the
405    empty string.  The variable values in 'vars' should not contain further
406    variable expansions; if 'vars' is the output of 'parse_makefile()',
407    you're fine.  Returns a variable-expanded version of 's'.
408    """
409
410    # This algorithm does multiple expansion, so if vars['foo'] contains
411    # "${bar}", it will expand ${foo} to ${bar}, and then expand
412    # ${bar}... and so forth.  This is fine as long as 'vars' comes from
413    # 'parse_makefile()', which takes care of such expansions eagerly,
414    # according to make's variable expansion semantics.
415
416    while True:
417        m = _findvar1_rx.search(s) or _findvar2_rx.search(s)
418        if m:
419            (beg, end) = m.span()
420            s = s[0:beg] + vars.get(m.group(1)) + s[end:]
421        else:
422            break
423    return s
424
425
426_config_vars = None
427
428def _init_posix():
429    """Initialize the module as appropriate for POSIX systems."""
430    # _sysconfigdata is generated at build time, see the sysconfig module
431    name = os.environ.get('_PYTHON_SYSCONFIGDATA_NAME',
432        '_sysconfigdata_{abi}_{platform}_{multiarch}'.format(
433        abi=sys.abiflags,
434        platform=sys.platform,
435        multiarch=getattr(sys.implementation, '_multiarch', ''),
436    ))
437    _temp = __import__(name, globals(), locals(), ['build_time_vars'], 0)
438    build_time_vars = _temp.build_time_vars
439    global _config_vars
440    _config_vars = {}
441    _config_vars.update(build_time_vars)
442
443
444def _init_nt():
445    """Initialize the module as appropriate for NT"""
446    g = {}
447    # set basic install directories
448    g['LIBDEST'] = get_python_lib(plat_specific=0, standard_lib=1)
449    g['BINLIBDEST'] = get_python_lib(plat_specific=1, standard_lib=1)
450
451    # XXX hmmm.. a normal install puts include files here
452    g['INCLUDEPY'] = get_python_inc(plat_specific=0)
453
454    g['EXT_SUFFIX'] = _imp.extension_suffixes()[0]
455    g['EXE'] = ".exe"
456    g['VERSION'] = get_python_version().replace(".", "")
457    g['BINDIR'] = os.path.dirname(os.path.abspath(sys.executable))
458
459    global _config_vars
460    _config_vars = g
461
462
463def get_config_vars(*args):
464    """With no arguments, return a dictionary of all configuration
465    variables relevant for the current platform.  Generally this includes
466    everything needed to build extensions and install both pure modules and
467    extensions.  On Unix, this means every variable defined in Python's
468    installed Makefile; on Windows it's a much smaller set.
469
470    With arguments, return a list of values that result from looking up
471    each argument in the configuration variable dictionary.
472    """
473    global _config_vars
474    if _config_vars is None:
475        func = globals().get("_init_" + os.name)
476        if func:
477            func()
478        else:
479            _config_vars = {}
480
481        # Normalized versions of prefix and exec_prefix are handy to have;
482        # in fact, these are the standard versions used most places in the
483        # Distutils.
484        _config_vars['prefix'] = PREFIX
485        _config_vars['exec_prefix'] = EXEC_PREFIX
486
487        # For backward compatibility, see issue19555
488        SO = _config_vars.get('EXT_SUFFIX')
489        if SO is not None:
490            _config_vars['SO'] = SO
491
492        # Always convert srcdir to an absolute path
493        srcdir = _config_vars.get('srcdir', project_base)
494        if os.name == 'posix':
495            if python_build:
496                # If srcdir is a relative path (typically '.' or '..')
497                # then it should be interpreted relative to the directory
498                # containing Makefile.
499                base = os.path.dirname(get_makefile_filename())
500                srcdir = os.path.join(base, srcdir)
501            else:
502                # srcdir is not meaningful since the installation is
503                # spread about the filesystem.  We choose the
504                # directory containing the Makefile since we know it
505                # exists.
506                srcdir = os.path.dirname(get_makefile_filename())
507        _config_vars['srcdir'] = os.path.abspath(os.path.normpath(srcdir))
508
509        # Convert srcdir into an absolute path if it appears necessary.
510        # Normally it is relative to the build directory.  However, during
511        # testing, for example, we might be running a non-installed python
512        # from a different directory.
513        if python_build and os.name == "posix":
514            base = project_base
515            if (not os.path.isabs(_config_vars['srcdir']) and
516                base != os.getcwd()):
517                # srcdir is relative and we are not in the same directory
518                # as the executable. Assume executable is in the build
519                # directory and make srcdir absolute.
520                srcdir = os.path.join(base, _config_vars['srcdir'])
521                _config_vars['srcdir'] = os.path.normpath(srcdir)
522
523        # OS X platforms require special customization to handle
524        # multi-architecture, multi-os-version installers
525        if sys.platform == 'darwin':
526            import _osx_support
527            _osx_support.customize_config_vars(_config_vars)
528
529    if args:
530        vals = []
531        for name in args:
532            vals.append(_config_vars.get(name))
533        return vals
534    else:
535        return _config_vars
536
537def get_config_var(name):
538    """Return the value of a single variable using the dictionary
539    returned by 'get_config_vars()'.  Equivalent to
540    get_config_vars().get(name)
541    """
542    if name == 'SO':
543        import warnings
544        warnings.warn('SO is deprecated, use EXT_SUFFIX', DeprecationWarning, 2)
545    return get_config_vars().get(name)
546