1"""distutils.extension 2 3Provides the Extension class, used to describe C/C++ extension 4modules in setup scripts.""" 5 6import os 7import warnings 8 9# This class is really only used by the "build_ext" command, so it might 10# make sense to put it in distutils.command.build_ext. However, that 11# module is already big enough, and I want to make this class a bit more 12# complex to simplify some common cases ("foo" module in "foo.c") and do 13# better error-checking ("foo.c" actually exists). 14# 15# Also, putting this in build_ext.py means every setup script would have to 16# import that large-ish module (indirectly, through distutils.core) in 17# order to do anything. 18 19class Extension: 20 """Just a collection of attributes that describes an extension 21 module and everything needed to build it (hopefully in a portable 22 way, but there are hooks that let you be as unportable as you need). 23 24 Instance attributes: 25 name : string 26 the full name of the extension, including any packages -- ie. 27 *not* a filename or pathname, but Python dotted name 28 sources : [string] 29 list of source filenames, relative to the distribution root 30 (where the setup script lives), in Unix form (slash-separated) 31 for portability. Source files may be C, C++, SWIG (.i), 32 platform-specific resource files, or whatever else is recognized 33 by the "build_ext" command as source for a Python extension. 34 include_dirs : [string] 35 list of directories to search for C/C++ header files (in Unix 36 form for portability) 37 define_macros : [(name : string, value : string|None)] 38 list of macros to define; each macro is defined using a 2-tuple, 39 where 'value' is either the string to define it to or None to 40 define it without a particular value (equivalent of "#define 41 FOO" in source or -DFOO on Unix C compiler command line) 42 undef_macros : [string] 43 list of macros to undefine explicitly 44 library_dirs : [string] 45 list of directories to search for C/C++ libraries at link time 46 libraries : [string] 47 list of library names (not filenames or paths) to link against 48 runtime_library_dirs : [string] 49 list of directories to search for C/C++ libraries at run time 50 (for shared extensions, this is when the extension is loaded) 51 extra_objects : [string] 52 list of extra files to link with (eg. object files not implied 53 by 'sources', static library that must be explicitly specified, 54 binary resource files, etc.) 55 extra_compile_args : [string] 56 any extra platform- and compiler-specific information to use 57 when compiling the source files in 'sources'. For platforms and 58 compilers where "command line" makes sense, this is typically a 59 list of command-line arguments, but for other platforms it could 60 be anything. 61 extra_link_args : [string] 62 any extra platform- and compiler-specific information to use 63 when linking object files together to create the extension (or 64 to create a new static Python interpreter). Similar 65 interpretation as for 'extra_compile_args'. 66 export_symbols : [string] 67 list of symbols to be exported from a shared extension. Not 68 used on all platforms, and not generally necessary for Python 69 extensions, which typically export exactly one symbol: "init" + 70 extension_name. 71 swig_opts : [string] 72 any extra options to pass to SWIG if a source file has the .i 73 extension. 74 depends : [string] 75 list of files that the extension depends on 76 language : string 77 extension language (i.e. "c", "c++", "objc"). Will be detected 78 from the source extensions if not provided. 79 optional : boolean 80 specifies that a build failure in the extension should not abort the 81 build process, but simply not install the failing extension. 82 """ 83 84 # When adding arguments to this constructor, be sure to update 85 # setup_keywords in core.py. 86 def __init__(self, name, sources, 87 include_dirs=None, 88 define_macros=None, 89 undef_macros=None, 90 library_dirs=None, 91 libraries=None, 92 runtime_library_dirs=None, 93 extra_objects=None, 94 extra_compile_args=None, 95 extra_link_args=None, 96 export_symbols=None, 97 swig_opts = None, 98 depends=None, 99 language=None, 100 optional=None, 101 **kw # To catch unknown keywords 102 ): 103 if not isinstance(name, str): 104 raise AssertionError("'name' must be a string") 105 if not (isinstance(sources, list) and 106 all(isinstance(v, str) for v in sources)): 107 raise AssertionError("'sources' must be a list of strings") 108 109 self.name = name 110 self.sources = sources 111 self.include_dirs = include_dirs or [] 112 self.define_macros = define_macros or [] 113 self.undef_macros = undef_macros or [] 114 self.library_dirs = library_dirs or [] 115 self.libraries = libraries or [] 116 self.runtime_library_dirs = runtime_library_dirs or [] 117 self.extra_objects = extra_objects or [] 118 self.extra_compile_args = extra_compile_args or [] 119 self.extra_link_args = extra_link_args or [] 120 self.export_symbols = export_symbols or [] 121 self.swig_opts = swig_opts or [] 122 self.depends = depends or [] 123 self.language = language 124 self.optional = optional 125 126 # If there are unknown keyword options, warn about them 127 if len(kw) > 0: 128 options = [repr(option) for option in kw] 129 options = ', '.join(sorted(options)) 130 msg = "Unknown Extension options: %s" % options 131 warnings.warn(msg) 132 133 def __repr__(self): 134 return '<%s.%s(%r) at %#x>' % ( 135 self.__class__.__module__, 136 self.__class__.__qualname__, 137 self.name, 138 id(self)) 139 140 141def read_setup_file(filename): 142 """Reads a Setup file and returns Extension instances.""" 143 from distutils.sysconfig import (parse_makefile, expand_makefile_vars, 144 _variable_rx) 145 146 from distutils.text_file import TextFile 147 from distutils.util import split_quoted 148 149 # First pass over the file to gather "VAR = VALUE" assignments. 150 vars = parse_makefile(filename) 151 152 # Second pass to gobble up the real content: lines of the form 153 # <module> ... [<sourcefile> ...] [<cpparg> ...] [<library> ...] 154 file = TextFile(filename, 155 strip_comments=1, skip_blanks=1, join_lines=1, 156 lstrip_ws=1, rstrip_ws=1) 157 try: 158 extensions = [] 159 160 while True: 161 line = file.readline() 162 if line is None: # eof 163 break 164 if _variable_rx.match(line): # VAR=VALUE, handled in first pass 165 continue 166 167 if line[0] == line[-1] == "*": 168 file.warn("'%s' lines not handled yet" % line) 169 continue 170 171 line = expand_makefile_vars(line, vars) 172 words = split_quoted(line) 173 174 # NB. this parses a slightly different syntax than the old 175 # makesetup script: here, there must be exactly one extension per 176 # line, and it must be the first word of the line. I have no idea 177 # why the old syntax supported multiple extensions per line, as 178 # they all wind up being the same. 179 180 module = words[0] 181 ext = Extension(module, []) 182 append_next_word = None 183 184 for word in words[1:]: 185 if append_next_word is not None: 186 append_next_word.append(word) 187 append_next_word = None 188 continue 189 190 suffix = os.path.splitext(word)[1] 191 switch = word[0:2] ; value = word[2:] 192 193 if suffix in (".c", ".cc", ".cpp", ".cxx", ".c++", ".m", ".mm"): 194 # hmm, should we do something about C vs. C++ sources? 195 # or leave it up to the CCompiler implementation to 196 # worry about? 197 ext.sources.append(word) 198 elif switch == "-I": 199 ext.include_dirs.append(value) 200 elif switch == "-D": 201 equals = value.find("=") 202 if equals == -1: # bare "-DFOO" -- no value 203 ext.define_macros.append((value, None)) 204 else: # "-DFOO=blah" 205 ext.define_macros.append((value[0:equals], 206 value[equals+2:])) 207 elif switch == "-U": 208 ext.undef_macros.append(value) 209 elif switch == "-C": # only here 'cause makesetup has it! 210 ext.extra_compile_args.append(word) 211 elif switch == "-l": 212 ext.libraries.append(value) 213 elif switch == "-L": 214 ext.library_dirs.append(value) 215 elif switch == "-R": 216 ext.runtime_library_dirs.append(value) 217 elif word == "-rpath": 218 append_next_word = ext.runtime_library_dirs 219 elif word == "-Xlinker": 220 append_next_word = ext.extra_link_args 221 elif word == "-Xcompiler": 222 append_next_word = ext.extra_compile_args 223 elif switch == "-u": 224 ext.extra_link_args.append(word) 225 if not value: 226 append_next_word = ext.extra_link_args 227 elif suffix in (".a", ".so", ".sl", ".o", ".dylib"): 228 # NB. a really faithful emulation of makesetup would 229 # append a .o file to extra_objects only if it 230 # had a slash in it; otherwise, it would s/.o/.c/ 231 # and append it to sources. Hmmmm. 232 ext.extra_objects.append(word) 233 else: 234 file.warn("unrecognized argument '%s'" % word) 235 236 extensions.append(ext) 237 finally: 238 file.close() 239 240 return extensions 241