Lib/distutils/extension.py

   1 """distutils.extension
   2
   3 Provides the Extension class, used to describe C/C++ extension
   4 modules in setup scripts."""
   5
   6 # created 2000/05/30, Greg Ward
   7
   8 __revision__ = "$Id$"
   9
  10 import os, string
  11 from types import *
  12
  13
  14 # This class is really only used by the "build_ext" command, so it might
  15 # make sense to put it in distutils.command.build_ext.  However, that
  16 # module is already big enough, and I want to make this class a bit more
  17 # complex to simplify some common cases ("foo" module in "foo.c") and do
  18 # better error-checking ("foo.c" actually exists).
  19 #
  20 # Also, putting this in build_ext.py means every setup script would have to
  21 # import that large-ish module (indirectly, through distutils.core) in
  22 # order to do anything.
  23
  24 class Extension:
  25     """Just a collection of attributes that describes an extension
  26     module and everything needed to build it (hopefully in a portable
  27     way, but there are hooks that let you be as unportable as you need).
  28
  29     Instance attributes:
  30       name : string
  31         the full name of the extension, including any packages -- ie.
  32         *not* a filename or pathname, but Python dotted name
  33       sources : [string]
  34         list of source filenames, relative to the distribution root
  35         (where the setup script lives), in Unix form (slash-separated)
  36         for portability.  Source files may be C, C++, SWIG (.i),
  37         platform-specific resource files, or whatever else is recognized
  38         by the "build_ext" command as source for a Python extension.
  39       include_dirs : [string]
  40         list of directories to search for C/C++ header files (in Unix
  41         form for portability)
  42       define_macros : [(name : string, value : string|None)]
  43         list of macros to define; each macro is defined using a 2-tuple,
  44         where 'value' is either the string to define it to or None to
  45         define it without a particular value (equivalent of "#define
  46         FOO" in source or -DFOO on Unix C compiler command line)
  47       undef_macros : [string]
  48         list of macros to undefine explicitly
  49       library_dirs : [string]
  50         list of directories to search for C/C++ libraries at link time
  51       libraries : [string]
  52         list of library names (not filenames or paths) to link against
  53       runtime_library_dirs : [string]
  54         list of directories to search for C/C++ libraries at run time
  55         (for shared extensions, this is when the extension is loaded)
  56       extra_objects : [string]
  57         list of extra files to link with (eg. object files not implied
  58         by 'sources', static library that must be explicitly specified,
  59         binary resource files, etc.)
  60       extra_compile_args : [string]
  61         any extra platform- and compiler-specific information to use
  62         when compiling the source files in 'sources'.  For platforms and
  63         compilers where "command line" makes sense, this is typically a
  64         list of command-line arguments, but for other platforms it could
  65         be anything.
  66       extra_link_args : [string]
  67         any extra platform- and compiler-specific information to use
  68         when linking object files together to create the extension (or
  69         to create a new static Python interpreter).  Similar
  70         interpretation as for 'extra_compile_args'.
  71       export_symbols : [string]
  72         list of symbols to be exported from a shared extension.  Not
  73         used on all platforms, and not generally necessary for Python
  74         extensions, which typically export exactly one symbol: "init" +
  75         extension_name.
  76     """
  77
  78     def __init__ (self, name, sources,
  79                   include_dirs=None,
  80                   define_macros=None,
  81                   undef_macros=None,
  82                   library_dirs=None,
  83                   libraries=None,
  84                   runtime_library_dirs=None,
  85                   extra_objects=None,
  86                   extra_compile_args=None,
  87                   extra_link_args=None,
  88                   export_symbols=None,
  89                  ):
  90
  91         assert type(name) is StringType, "'name' must be a string"
  92         assert (type(sources) is ListType and
  93                 map(type, sources) == [StringType]*len(sources)), \
  94                 "'sources' must be a list of strings"
  95
  96         self.name = name
  97         self.sources = sources
  98         self.include_dirs = include_dirs or []
  99         self.define_macros = define_macros or []
 100         self.undef_macros = undef_macros or []
 101         self.library_dirs = library_dirs or []
 102         self.libraries = libraries or []
 103         self.runtime_library_dirs = runtime_library_dirs or []
 104         self.extra_objects = extra_objects or []
 105         self.extra_compile_args = extra_compile_args or []
 106         self.extra_link_args = extra_link_args or []
 107         self.export_symbols = export_symbols or []
 108
 109 # class Extension
 110
 111
 112 def read_setup_file (filename):
 113     from distutils.sysconfig import \
 114          parse_makefile, expand_makefile_vars, _variable_rx
 115     from distutils.text_file import TextFile
 116     from distutils.util import split_quoted
 117
 118     # First pass over the file to gather "VAR = VALUE" assignments.
 119     vars = parse_makefile(filename)
 120
 121     # Second pass to gobble up the real content: lines of the form
 122     #   <module> ... [<sourcefile> ...] [<cpparg> ...] [<library> ...]
 123     file = TextFile(filename,
 124                     strip_comments=1, skip_blanks=1, join_lines=1,
 125                     lstrip_ws=1, rstrip_ws=1)
 126     extensions = []
 127
 128     while 1:
 129         line = file.readline()
 130         if line is None:                # eof
 131             break
 132         if _variable_rx.match(line):    # VAR=VALUE, handled in first pass
 133             continue
 134
 135         if line[0] == line[-1] == "*":
 136             file.warn("'%s' lines not handled yet" % line)
 137             continue
 138
 139         #print "original line: " + line
 140         line = expand_makefile_vars(line, vars)
 141         words = split_quoted(line)
 142         #print "expanded line: " + line
 143
 144         # NB. this parses a slightly different syntax than the old
 145         # makesetup script: here, there must be exactly one extension per
 146         # line, and it must be the first word of the line.  I have no idea
 147         # why the old syntax supported multiple extensions per line, as
 148         # they all wind up being the same.
 149
 150         module = words[0]
 151         ext = Extension(module, [])
 152         append_next_word = None
 153
 154         for word in words[1:]:
 155             if append_next_word is not None:
 156                 append_next_word.append(word)
 157                 append_next_word = None
 158                 continue
 159
 160             suffix = os.path.splitext(word)[1]
 161             switch = word[0:2] ; value = word[2:]
 162
 163             if suffix in (".c", ".cc", ".cpp", ".cxx", ".c++"):
 164                 # hmm, should we do something about C vs. C++ sources?
 165                 # or leave it up to the CCompiler implementation to
 166                 # worry about?
 167                 ext.sources.append(word)
 168             elif switch == "-I":
 169                 ext.include_dirs.append(value)
 170             elif switch == "-D":
 171                 equals = string.find(value, "=")
 172                 if equals == -1:        # bare "-DFOO" -- no value
 173                     ext.define_macros.append((value, None))
 174                 else:                   # "-DFOO=blah"
 175                     ext.define_macros.append((value[0:equals],
 176                                               value[equals+2:]))
 177             elif switch == "-U":
 178                 ext.undef_macros.append(value)
 179             elif switch == "-C":        # only here 'cause makesetup has it!
 180                 ext.extra_compile_args.append(word)
 181             elif switch == "-l":
 182                 ext.libraries.append(value)
 183             elif switch == "-L":
 184                 ext.library_dirs.append(value)
 185             elif switch == "-R":
 186                 ext.runtime_library_dirs.append(value)
 187             elif word == "-rpath":
 188                 append_next_word = ext.runtime_library_dirs
 189             elif word == "-Xlinker":
 190                 append_next_word = ext.extra_link_args
 191             elif switch == "-u":
 192                 ext.extra_link_args.append(word)
 193                 if not value:
 194                     append_next_word = ext.extra_link_args
 195             elif suffix in (".a", ".so", ".sl", ".o"):
 196                 # NB. a really faithful emulation of makesetup would
 197                 # append a .o file to extra_objects only if it
 198                 # had a slash in it; otherwise, it would s/.o/.c/
 199                 # and append it to sources.  Hmmmm.
 200                 ext.extra_objects.append(word)
 201             else:
 202                 file.warn("unrecognized argument '%s'" % word)
 203
 204         extensions.append(ext)
 205
 206         #print "module:", module
 207         #print "source files:", source_files
 208         #print "cpp args:", cpp_args
 209         #print "lib args:", library_args
 210
 211         #extensions[module] = { 'sources': source_files,
 212         #                       'cpp_args': cpp_args,
 213         #                       'lib_args': library_args }
 214
 215     return extensions
 216
 217 # read_setup_file ()