"""distutils.extension



Provides the Extension class, used to describe C/C++ extension

modules in setup scripts."""



__revision__ = "$Id: extension.py 37623 2004-10-14 10:02:08Z anthonybaxter $"



import os, string, sys

from types import *



try:

    import warnings

except ImportError:

    warnings = None



# This class is really only used by the "build_ext" command, so it might

# make sense to put it in distutils.command.build_ext.  However, that

# module is already big enough, and I want to make this class a bit more

# complex to simplify some common cases ("foo" module in "foo.c") and do

# better error-checking ("foo.c" actually exists).

#

# Also, putting this in build_ext.py means every setup script would have to

# import that large-ish module (indirectly, through distutils.core) in

# order to do anything.



class Extension:

    """Just a collection of attributes that describes an extension

    module and everything needed to build it (hopefully in a portable

    way, but there are hooks that let you be as unportable as you need).



    Instance attributes:

      name : string

        the full name of the extension, including any packages -- ie.

        *not* a filename or pathname, but Python dotted name

      sources : [string]

        list of source filenames, relative to the distribution root

        (where the setup script lives), in Unix form (slash-separated)

        for portability.  Source files may be C, C++, SWIG (.i),

        platform-specific resource files, or whatever else is recognized

        by the "build_ext" command as source for a Python extension.

      include_dirs : [string]

        list of directories to search for C/C++ header files (in Unix

        form for portability)

      define_macros : [(name : string, value : string|None)]

        list of macros to define; each macro is defined using a 2-tuple,

        where 'value' is either the string to define it to or None to

        define it without a particular value (equivalent of "#define

        FOO" in source or -DFOO on Unix C compiler command line)

      undef_macros : [string]

        list of macros to undefine explicitly

      library_dirs : [string]

        list of directories to search for C/C++ libraries at link time

      libraries : [string]

        list of library names (not filenames or paths) to link against

      runtime_library_dirs : [string]

        list of directories to search for C/C++ libraries at run time

        (for shared extensions, this is when the extension is loaded)

      extra_objects : [string]

        list of extra files to link with (eg. object files not implied

        by 'sources', static library that must be explicitly specified,

        binary resource files, etc.)

      extra_compile_args : [string]

        any extra platform- and compiler-specific information to use

        when compiling the source files in 'sources'.  For platforms and

        compilers where "command line" makes sense, this is typically a

        list of command-line arguments, but for other platforms it could

        be anything.

      extra_link_args : [string]

        any extra platform- and compiler-specific information to use

        when linking object files together to create the extension (or

        to create a new static Python interpreter).  Similar

        interpretation as for 'extra_compile_args'.

      export_symbols : [string]

        list of symbols to be exported from a shared extension.  Not

        used on all platforms, and not generally necessary for Python

        extensions, which typically export exactly one symbol: "init" +

        extension_name.

      swig_opts : [string]

        any extra options to pass to SWIG if a source file has the .i

        extension.

      depends : [string]

        list of files that the extension depends on

      language : string

        extension language (i.e. "c", "c++", "objc"). Will be detected

        from the source extensions if not provided.

    """



    # When adding arguments to this constructor, be sure to update

    # setup_keywords in core.py.

    def __init__ (self, name, sources,

                  include_dirs=None,

                  define_macros=None,

                  undef_macros=None,

                  library_dirs=None,

                  libraries=None,

                  runtime_library_dirs=None,

                  extra_objects=None,

                  extra_compile_args=None,

                  extra_link_args=None,

                  export_symbols=None,

                  swig_opts = None,

                  depends=None,

                  language=None,

                  **kw                      # To catch unknown keywords

                 ):

        assert type(name) is StringType, "'name' must be a string"

        assert (type(sources) is ListType and

                map(type, sources) == [StringType]*len(sources)), \

                "'sources' must be a list of strings"



        self.name = name

        self.sources = sources

        self.include_dirs = include_dirs or []

        self.define_macros = define_macros or []

        self.undef_macros = undef_macros or []

        self.library_dirs = library_dirs or []

        self.libraries = libraries or []

        self.runtime_library_dirs = runtime_library_dirs or []

        self.extra_objects = extra_objects or []

        self.extra_compile_args = extra_compile_args or []

        self.extra_link_args = extra_link_args or []

        self.export_symbols = export_symbols or []

        self.swig_opts = swig_opts or []

        self.depends = depends or []

        self.language = language



        # If there are unknown keyword options, warn about them

        if len(kw):

            L = kw.keys() ; L.sort()

            L = map(repr, L)

            msg = "Unknown Extension options: " + string.join(L, ', ')

            if warnings is not None:

                warnings.warn(msg)

            else:

                sys.stderr.write(msg + '\n')

# class Extension





def read_setup_file (filename):

    from distutils.sysconfig import \

         parse_makefile, expand_makefile_vars, _variable_rx

    from distutils.text_file import TextFile

    from distutils.util import split_quoted



    # First pass over the file to gather "VAR = VALUE" assignments.

    vars = parse_makefile(filename)



    # Second pass to gobble up the real content: lines of the form

    #   <module> ... [<sourcefile> ...] [<cpparg> ...] [<library> ...]

    file = TextFile(filename,

                    strip_comments=1, skip_blanks=1, join_lines=1,

                    lstrip_ws=1, rstrip_ws=1)

    extensions = []



    while 1:

        line = file.readline()

        if line is None:                # eof

            break

        if _variable_rx.match(line):    # VAR=VALUE, handled in first pass

            continue



        if line[0] == line[-1] == "*":

            file.warn("'%s' lines not handled yet" % line)

            continue



        #print "original line: " + line

        line = expand_makefile_vars(line, vars)

        words = split_quoted(line)

        #print "expanded line: " + line



        # NB. this parses a slightly different syntax than the old

        # makesetup script: here, there must be exactly one extension per

        # line, and it must be the first word of the line.  I have no idea

        # why the old syntax supported multiple extensions per line, as

        # they all wind up being the same.



        module = words[0]

        ext = Extension(module, [])

        append_next_word = None



        for word in words[1:]:

            if append_next_word is not None:

                append_next_word.append(word)

                append_next_word = None

                continue



            suffix = os.path.splitext(word)[1]

            switch = word[0:2] ; value = word[2:]



            if suffix in (".c", ".cc", ".cpp", ".cxx", ".c++", ".m", ".mm"):

                # hmm, should we do something about C vs. C++ sources?

                # or leave it up to the CCompiler implementation to

                # worry about?

                ext.sources.append(word)

            elif switch == "-I":

                ext.include_dirs.append(value)

            elif switch == "-D":

                equals = string.find(value, "=")

                if equals == -1:        # bare "-DFOO" -- no value

                    ext.define_macros.append((value, None))

                else:                   # "-DFOO=blah"

                    ext.define_macros.append((value[0:equals],

                                              value[equals+2:]))

            elif switch == "-U":

                ext.undef_macros.append(value)

            elif switch == "-C":        # only here 'cause makesetup has it!

                ext.extra_compile_args.append(word)

            elif switch == "-l":

                ext.libraries.append(value)

            elif switch == "-L":

                ext.library_dirs.append(value)

            elif switch == "-R":

                ext.runtime_library_dirs.append(value)

            elif word == "-rpath":

                append_next_word = ext.runtime_library_dirs

            elif word == "-Xlinker":

                append_next_word = ext.extra_link_args

            elif word == "-Xcompiler":

                append_next_word = ext.extra_compile_args

            elif switch == "-u":

                ext.extra_link_args.append(word)

                if not value:

                    append_next_word = ext.extra_link_args

            elif suffix in (".a", ".so", ".sl", ".o", ".dylib"):

                # NB. a really faithful emulation of makesetup would

                # append a .o file to extra_objects only if it

                # had a slash in it; otherwise, it would s/.o/.c/

                # and append it to sources.  Hmmmm.

                ext.extra_objects.append(word)

            else:

                file.warn("unrecognized argument '%s'" % word)



        extensions.append(ext)



        #print "module:", module

        #print "source files:", source_files

        #print "cpp args:", cpp_args

        #print "lib args:", library_args



        #extensions[module] = { 'sources': source_files,

        #                       'cpp_args': cpp_args,

        #                       'lib_args': library_args }



    return extensions



# read_setup_file ()

