Lib/distutils/sysconfig.py

   1 """Provide access to Python's configuration information.  The specific names
   2 defined in the module depend heavily on the platform and configuration.
   3
   4 Written by:   Fred L. Drake, Jr.
   5 Email:        <fdrake@acm.org>
   6 Initial date: 17-Dec-1998
   7 """
   8
   9 __version__ = "$Revision$"
  10
  11 import os
  12 import re
  13 import string
  14 import sys
  15
  16
  17 def get_config_h_filename():
  18     """Return full pathname of installed config.h file."""
  19     return os.path.join(sys.exec_prefix, "include", "python" + sys.version[:3],
  20                         "config.h")
  21
  22 def get_makefile_filename():
  23     """Return full pathname of installed Makefile from the Python build."""
  24     return os.path.join(sys.exec_prefix, "lib", "python" + sys.version[:3],
  25                         "config", "Makefile")
  26
  27 def parse_config_h(fp, g=None):
  28     """Parse a config.h-style file.  A dictionary containing name/value
  29     pairs is returned.  If an optional dictionary is passed in as the second
  30     argument, it is used instead of a new dictionary.
  31     """
  32     if g is None:
  33         g = {}
  34     define_rx = re.compile("#define ([A-Z][A-Z0-9_]+) (.*)\n")
  35     undef_rx = re.compile("/[*] #undef ([A-Z][A-Z0-9_]+) [*]/\n")
  36     #
  37     while 1:
  38         line = fp.readline()
  39         if not line:
  40             break
  41         m = define_rx.match(line)
  42         if m:
  43             n, v = m.group(1, 2)
  44             try: v = string.atoi(v)
  45             except ValueError: pass
  46             g[n] = v
  47         else:
  48             m = undef_rx.match(line)
  49             if m:
  50                 g[m.group(1)] = 0
  51     return g
  52
  53 def parse_makefile(fp, g=None):
  54     """Parse a Makefile-style file.  A dictionary containing name/value
  55     pairs is returned.  If an optional dictionary is passed in as the second
  56     argument, it is used instead of a new dictionary.
  57     """
  58     if g is None:
  59         g = {}
  60     variable_rx = re.compile("([a-zA-Z][a-zA-Z0-9_]+)\s*=\s*(.*)\n")
  61     done = {}
  62     notdone = {}
  63     #
  64     while 1:
  65         line = fp.readline()
  66         if not line:
  67             break
  68         m = variable_rx.match(line)
  69         if m:
  70             n, v = m.group(1, 2)
  71             v = string.strip(v)
  72             if "$" in v:
  73                 notdone[n] = v
  74             else:
  75                 try: v = string.atoi(v)
  76                 except ValueError: pass
  77                 done[n] = v
  78
  79     # do variable interpolation here
  80     findvar1_rx = re.compile(r"\$\(([A-Za-z][A-Za-z0-9_]*)\)")
  81     findvar2_rx = re.compile(r"\${([A-Za-z][A-Za-z0-9_]*)}")
  82     while notdone:
  83         for name in notdone.keys():
  84             value = notdone[name]
  85             m = findvar1_rx.search(value)
  86             if not m:
  87                 m = findvar2_rx.search(value)
  88             if m:
  89                 n = m.group(1)
  90                 if done.has_key(n):
  91                     after = value[m.end():]
  92                     value = value[:m.start()] + done[n] + after
  93                     if "$" in after:
  94                         notdone[name] = value
  95                     else:
  96                         try: value = string.atoi(value)
  97                         except ValueError: pass
  98                         done[name] = string.strip(value)
  99                         del notdone[name]
 100                 elif notdone.has_key(n):
 101                     # get it on a subsequent round
 102                     pass
 103                 else:
 104                     done[n] = ""
 105                     after = value[m.end():]
 106                     value = value[:m.start()] + after
 107                     if "$" in after:
 108                         notdone[name] = value
 109                     else:
 110                         try: value = string.atoi(value)
 111                         except ValueError: pass
 112                         done[name] = string.strip(value)
 113                         del notdone[name]
 114             else:
 115                 # bogus variable reference; just drop it since we can't deal
 116                 del notdone[name]
 117
 118     # save the results in the global dictionary
 119     g.update(done)
 120     return g
 121
 122
 123 def _init_posix():
 124     """Initialize the module as appropriate for POSIX systems."""
 125     g = globals()
 126     # load the installed config.h:
 127     parse_config_h(open(get_config_h_filename()), g)
 128     # load the installed Makefile.pre.in:
 129     parse_makefile(open(get_makefile_filename()), g)
 130
 131
 132
 133 try:
 134     exec "_init_" + os.name
 135 except NameError:
 136     # not needed for this platform
 137     pass
 138 else:
 139     exec "_init_%s()" % os.name
 140
 141 del _init_posix