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 __revision__ = "$Id$"
   7
   8 import os
   9 import sys
  10 import warnings
  11
  12 # This class is really only used by the "build_ext" command, so it might
  13 # make sense to put it in distutils.command.build_ext.  However, that
  14 # module is already big enough, and I want to make this class a bit more
  15 # complex to simplify some common cases ("foo" module in "foo.c") and do
  16 # better error-checking ("foo.c" actually exists).
  17 #
  18 # Also, putting this in build_ext.py means every setup script would have to
  19 # import that large-ish module (indirectly, through distutils.core) in
  20 # order to do anything.
  21
  22 class Extension:
  23     """Just a collection of attributes that describes an extension
  24     module and everything needed to build it (hopefully in a portable
  25     way, but there are hooks that let you be as unportable as you need).
  26
  27     Instance attributes:
  28       name : string
  29         the full name of the extension, including any packages -- ie.
  30         *not* a filename or pathname, but Python dotted name
  31       sources : [string]
  32         list of source filenames, relative to the distribution root
  33         (where the setup script lives), in Unix form (slash-separated)
  34         for portability.  Source files may be C, C++, SWIG (.i),
  35         platform-specific resource files, or whatever else is recognized
  36         by the "build_ext" command as source for a Python extension.
  37       include_dirs : [string]
  38         list of directories to search for C/C++ header files (in Unix
  39         form for portability)
  40       define_macros : [(name : string, value : string|None)]
  41         list of macros to define; each macro is defined using a 2-tuple,
  42         where 'value' is either the string to define it to or None to
  43         define it without a particular value (equivalent of "#define
  44         FOO" in source or -DFOO on Unix C compiler command line)
  45       undef_macros : [string]
  46         list of macros to undefine explicitly
  47       library_dirs : [string]
  48         list of directories to search for C/C++ libraries at link time
  49       libraries : [string]
  50         list of library names (not filenames or paths) to link against
  51       runtime_library_dirs : [string]
  52         list of directories to search for C/C++ libraries at run time
  53         (for shared extensions, this is when the extension is loaded)
  54       extra_objects : [string]
  55         list of extra files to link with (eg. object files not implied
  56         by 'sources', static library that must be explicitly specified,
  57         binary resource files, etc.)
  58       extra_compile_args : [string]
  59         any extra platform- and compiler-specific information to use
  60         when compiling the source files in 'sources'.  For platforms and
  61         compilers where "command line" makes sense, this is typically a
  62         list of command-line arguments, but for other platforms it could
  63         be anything.
  64       extra_link_args : [string]
  65         any extra platform- and compiler-specific information to use
  66         when linking object files together to create the extension (or
  67         to create a new static Python interpreter).  Similar
  68         interpretation as for 'extra_compile_args'.
  69       export_symbols : [string]
  70         list of symbols to be exported from a shared extension.  Not
  71         used on all platforms, and not generally necessary for Python
  72         extensions, which typically export exactly one symbol: "init" +
  73         extension_name.
  74       swig_opts : [string]
  75         any extra options to pass to SWIG if a source file has the .i
  76         extension.
  77       depends : [string]
  78         list of files that the extension depends on
  79       language : string
  80         extension language (i.e. "c", "c++", "objc"). Will be detected
  81         from the source extensions if not provided.
  82       optional : boolean
  83         specifies that a build failure in the extension should not abort the
  84         build process, but simply not install the failing extension.
  85     """
  86
  87     # When adding arguments to this constructor, be sure to update
  88     # setup_keywords in core.py.
  89     def __init__ (self, name, sources,
  90                   include_dirs=None,
  91                   define_macros=None,
  92                   undef_macros=None,
  93                   library_dirs=None,
  94                   libraries=None,
  95                   runtime_library_dirs=None,
  96                   extra_objects=None,
  97                   extra_compile_args=None,
  98                   extra_link_args=None,
  99                   export_symbols=None,
 100                   swig_opts = None,
 101                   depends=None,
 102                   language=None,
 103                   optional=None,
 104                   **kw                      # To catch unknown keywords
 105                  ):
 106         if not isinstance(name, str):
 107             raise AssertionError("'name' must be a string")
 108         if not (isinstance(sources, list) and
 109                 all(isinstance(v, str) for v in sources)):
 110             raise AssertionError("'sources' must be a list of strings")
 111
 112         self.name = name
 113         self.sources = sources
 114         self.include_dirs = include_dirs or []
 115         self.define_macros = define_macros or []
 116         self.undef_macros = undef_macros or []
 117         self.library_dirs = library_dirs or []
 118         self.libraries = libraries or []
 119         self.runtime_library_dirs = runtime_library_dirs or []
 120         self.extra_objects = extra_objects or []
 121         self.extra_compile_args = extra_compile_args or []
 122         self.extra_link_args = extra_link_args or []
 123         self.export_symbols = export_symbols or []
 124         self.swig_opts = swig_opts or []
 125         self.depends = depends or []
 126         self.language = language
 127         self.optional = optional
 128
 129         # If there are unknown keyword options, warn about them
 130         if len(kw) > 0:
 131             options = [repr(option) for option in kw]
 132             options = ', '.join(sorted(options))
 133             msg = "Unknown Extension options: %s" % options
 134             warnings.warn(msg)
 135
 136 def read_setup_file(filename):
 137     """Reads a Setup file and returns Extension instances."""
 138     from distutils.sysconfig import (parse_makefile, expand_makefile_vars,
 139                                      _variable_rx)
 140
 141     from distutils.text_file import TextFile
 142     from distutils.util import split_quoted
 143
 144     # First pass over the file to gather "VAR = VALUE" assignments.
 145     vars = parse_makefile(filename)
 146
 147     # Second pass to gobble up the real content: lines of the form
 148     #   <module> ... [<sourcefile> ...] [<cpparg> ...] [<library> ...]
 149     file = TextFile(filename,
 150                     strip_comments=1, skip_blanks=1, join_lines=1,
 151                     lstrip_ws=1, rstrip_ws=1)
 152     extensions = []
 153
 154     while 1:
 155         line = file.readline()
 156         if line is None:                # eof
 157             break
 158         if _variable_rx.match(line):    # VAR=VALUE, handled in first pass
 159             continue
 160
 161         if line[0] == line[-1] == "*":
 162             file.warn("'%s' lines not handled yet" % line)
 163             continue
 164
 165         line = expand_makefile_vars(line, vars)
 166         words = split_quoted(line)
 167
 168         # NB. this parses a slightly different syntax than the old
 169         # makesetup script: here, there must be exactly one extension per
 170         # line, and it must be the first word of the line.  I have no idea
 171         # why the old syntax supported multiple extensions per line, as
 172         # they all wind up being the same.
 173
 174         module = words[0]
 175         ext = Extension(module, [])
 176         append_next_word = None
 177
 178         for word in words[1:]:
 179             if append_next_word is not None:
 180                 append_next_word.append(word)
 181                 append_next_word = None
 182                 continue
 183
 184             suffix = os.path.splitext(word)[1]
 185             switch = word[0:2] ; value = word[2:]
 186
 187             if suffix in (".c", ".cc", ".cpp", ".cxx", ".c++", ".m", ".mm"):
 188                 # hmm, should we do something about C vs. C++ sources?
 189                 # or leave it up to the CCompiler implementation to
 190                 # worry about?
 191                 ext.sources.append(word)
 192             elif switch == "-I":
 193                 ext.include_dirs.append(value)
 194             elif switch == "-D":
 195                 equals = value.find("=")
 196                 if equals == -1:        # bare "-DFOO" -- no value
 197                     ext.define_macros.append((value, None))
 198                 else:                   # "-DFOO=blah"
 199                     ext.define_macros.append((value[0:equals],
 200                                               value[equals+2:]))
 201             elif switch == "-U":
 202                 ext.undef_macros.append(value)
 203             elif switch == "-C":        # only here 'cause makesetup has it!
 204                 ext.extra_compile_args.append(word)
 205             elif switch == "-l":
 206                 ext.libraries.append(value)
 207             elif switch == "-L":
 208                 ext.library_dirs.append(value)
 209             elif switch == "-R":
 210                 ext.runtime_library_dirs.append(value)
 211             elif word == "-rpath":
 212                 append_next_word = ext.runtime_library_dirs
 213             elif word == "-Xlinker":
 214                 append_next_word = ext.extra_link_args
 215             elif word == "-Xcompiler":
 216                 append_next_word = ext.extra_compile_args
 217             elif switch == "-u":
 218                 ext.extra_link_args.append(word)
 219                 if not value:
 220                     append_next_word = ext.extra_link_args
 221             elif suffix in (".a", ".so", ".sl", ".o", ".dylib"):
 222                 # NB. a really faithful emulation of makesetup would
 223                 # append a .o file to extra_objects only if it
 224                 # had a slash in it; otherwise, it would s/.o/.c/
 225                 # and append it to sources.  Hmmmm.
 226                 ext.extra_objects.append(word)
 227             else:
 228                 file.warn("unrecognized argument '%s'" % word)
 229
 230         extensions.append(ext)
 231
 232     return extensions