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-rw-r--r--Lib/packaging/command/config.py349
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diff --git a/Lib/packaging/command/config.py b/Lib/packaging/command/config.py
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+"""Prepare the build.
+
+This module provides config, a (mostly) empty command class
+that exists mainly to be sub-classed by specific module distributions and
+applications. The idea is that while every "config" command is different,
+at least they're all named the same, and users always see "config" in the
+list of standard commands. Also, this is a good place to put common
+configure-like tasks: "try to compile this C code", or "figure out where
+this header file lives".
+"""
+
+import os
+import re
+
+from packaging.command.cmd import Command
+from packaging.errors import PackagingExecError
+from packaging.compiler import customize_compiler
+from packaging import logger
+
+LANG_EXT = {'c': '.c', 'c++': '.cxx'}
+
+class config(Command):
+
+ description = "prepare the build"
+
+ user_options = [
+ ('compiler=', None,
+ "specify the compiler type"),
+ ('cc=', None,
+ "specify the compiler executable"),
+ ('include-dirs=', 'I',
+ "list of directories to search for header files"),
+ ('define=', 'D',
+ "C preprocessor macros to define"),
+ ('undef=', 'U',
+ "C preprocessor macros to undefine"),
+ ('libraries=', 'l',
+ "external C libraries to link with"),
+ ('library-dirs=', 'L',
+ "directories to search for external C libraries"),
+
+ ('noisy', None,
+ "show every action (compile, link, run, ...) taken"),
+ ('dump-source', None,
+ "dump generated source files before attempting to compile them"),
+ ]
+
+
+ # The three standard command methods: since the "config" command
+ # does nothing by default, these are empty.
+
+ def initialize_options(self):
+ self.compiler = None
+ self.cc = None
+ self.include_dirs = None
+ self.libraries = None
+ self.library_dirs = None
+
+ # maximal output for now
+ self.noisy = True
+ self.dump_source = True
+
+ # list of temporary files generated along-the-way that we have
+ # to clean at some point
+ self.temp_files = []
+
+ def finalize_options(self):
+ if self.include_dirs is None:
+ self.include_dirs = self.distribution.include_dirs or []
+ elif isinstance(self.include_dirs, str):
+ self.include_dirs = self.include_dirs.split(os.pathsep)
+
+ if self.libraries is None:
+ self.libraries = []
+ elif isinstance(self.libraries, str):
+ self.libraries = [self.libraries]
+
+ if self.library_dirs is None:
+ self.library_dirs = []
+ elif isinstance(self.library_dirs, str):
+ self.library_dirs = self.library_dirs.split(os.pathsep)
+
+ def run(self):
+ pass
+
+
+ # Utility methods for actual "config" commands. The interfaces are
+ # loosely based on Autoconf macros of similar names. Sub-classes
+ # may use these freely.
+
+ def _check_compiler(self):
+ """Check that 'self.compiler' really is a CCompiler object;
+ if not, make it one.
+ """
+ # We do this late, and only on-demand, because this is an expensive
+ # import.
+ from packaging.compiler.ccompiler import CCompiler
+ from packaging.compiler import new_compiler
+ if not isinstance(self.compiler, CCompiler):
+ self.compiler = new_compiler(compiler=self.compiler,
+ dry_run=self.dry_run, force=True)
+ customize_compiler(self.compiler)
+ if self.include_dirs:
+ self.compiler.set_include_dirs(self.include_dirs)
+ if self.libraries:
+ self.compiler.set_libraries(self.libraries)
+ if self.library_dirs:
+ self.compiler.set_library_dirs(self.library_dirs)
+
+
+ def _gen_temp_sourcefile(self, body, headers, lang):
+ filename = "_configtest" + LANG_EXT[lang]
+ with open(filename, "w") as file:
+ if headers:
+ for header in headers:
+ file.write("#include <%s>\n" % header)
+ file.write("\n")
+ file.write(body)
+ if body[-1] != "\n":
+ file.write("\n")
+ return filename
+
+ def _preprocess(self, body, headers, include_dirs, lang):
+ src = self._gen_temp_sourcefile(body, headers, lang)
+ out = "_configtest.i"
+ self.temp_files.extend((src, out))
+ self.compiler.preprocess(src, out, include_dirs=include_dirs)
+ return src, out
+
+ def _compile(self, body, headers, include_dirs, lang):
+ src = self._gen_temp_sourcefile(body, headers, lang)
+ if self.dump_source:
+ dump_file(src, "compiling '%s':" % src)
+ obj = self.compiler.object_filenames([src])[0]
+ self.temp_files.extend((src, obj))
+ self.compiler.compile([src], include_dirs=include_dirs)
+ return src, obj
+
+ def _link(self, body, headers, include_dirs, libraries, library_dirs,
+ lang):
+ src, obj = self._compile(body, headers, include_dirs, lang)
+ prog = os.path.splitext(os.path.basename(src))[0]
+ self.compiler.link_executable([obj], prog,
+ libraries=libraries,
+ library_dirs=library_dirs,
+ target_lang=lang)
+
+ if self.compiler.exe_extension is not None:
+ prog = prog + self.compiler.exe_extension
+ self.temp_files.append(prog)
+
+ return src, obj, prog
+
+ def _clean(self, *filenames):
+ if not filenames:
+ filenames = self.temp_files
+ self.temp_files = []
+ logger.info("removing: %s", ' '.join(filenames))
+ for filename in filenames:
+ try:
+ os.remove(filename)
+ except OSError:
+ pass
+
+
+ # XXX these ignore the dry-run flag: what to do, what to do? even if
+ # you want a dry-run build, you still need some sort of configuration
+ # info. My inclination is to make it up to the real config command to
+ # consult 'dry_run', and assume a default (minimal) configuration if
+ # true. The problem with trying to do it here is that you'd have to
+ # return either true or false from all the 'try' methods, neither of
+ # which is correct.
+
+ # XXX need access to the header search path and maybe default macros.
+
+ def try_cpp(self, body=None, headers=None, include_dirs=None, lang="c"):
+ """Construct a source file from 'body' (a string containing lines
+ of C/C++ code) and 'headers' (a list of header files to include)
+ and run it through the preprocessor. Return true if the
+ preprocessor succeeded, false if there were any errors.
+ ('body' probably isn't of much use, but what the heck.)
+ """
+ from packaging.compiler.ccompiler import CompileError
+ self._check_compiler()
+ ok = True
+ try:
+ self._preprocess(body, headers, include_dirs, lang)
+ except CompileError:
+ ok = False
+
+ self._clean()
+ return ok
+
+ def search_cpp(self, pattern, body=None, headers=None, include_dirs=None,
+ lang="c"):
+ """Construct a source file (just like 'try_cpp()'), run it through
+ the preprocessor, and return true if any line of the output matches
+ 'pattern'. 'pattern' should either be a compiled regex object or a
+ string containing a regex. If both 'body' and 'headers' are None,
+ preprocesses an empty file -- which can be useful to determine the
+ symbols the preprocessor and compiler set by default.
+ """
+ self._check_compiler()
+ src, out = self._preprocess(body, headers, include_dirs, lang)
+
+ if isinstance(pattern, str):
+ pattern = re.compile(pattern)
+
+ with open(out) as file:
+ match = False
+ while True:
+ line = file.readline()
+ if line == '':
+ break
+ if pattern.search(line):
+ match = True
+ break
+
+ self._clean()
+ return match
+
+ def try_compile(self, body, headers=None, include_dirs=None, lang="c"):
+ """Try to compile a source file built from 'body' and 'headers'.
+ Return true on success, false otherwise.
+ """
+ from packaging.compiler.ccompiler import CompileError
+ self._check_compiler()
+ try:
+ self._compile(body, headers, include_dirs, lang)
+ ok = True
+ except CompileError:
+ ok = False
+
+ logger.info(ok and "success!" or "failure.")
+ self._clean()
+ return ok
+
+ def try_link(self, body, headers=None, include_dirs=None, libraries=None,
+ library_dirs=None, lang="c"):
+ """Try to compile and link a source file, built from 'body' and
+ 'headers', to executable form. Return true on success, false
+ otherwise.
+ """
+ from packaging.compiler.ccompiler import CompileError, LinkError
+ self._check_compiler()
+ try:
+ self._link(body, headers, include_dirs,
+ libraries, library_dirs, lang)
+ ok = True
+ except (CompileError, LinkError):
+ ok = False
+
+ logger.info(ok and "success!" or "failure.")
+ self._clean()
+ return ok
+
+ def try_run(self, body, headers=None, include_dirs=None, libraries=None,
+ library_dirs=None, lang="c"):
+ """Try to compile, link to an executable, and run a program
+ built from 'body' and 'headers'. Return true on success, false
+ otherwise.
+ """
+ from packaging.compiler.ccompiler import CompileError, LinkError
+ self._check_compiler()
+ try:
+ src, obj, exe = self._link(body, headers, include_dirs,
+ libraries, library_dirs, lang)
+ self.spawn([exe])
+ ok = True
+ except (CompileError, LinkError, PackagingExecError):
+ ok = False
+
+ logger.info(ok and "success!" or "failure.")
+ self._clean()
+ return ok
+
+
+ # -- High-level methods --------------------------------------------
+ # (these are the ones that are actually likely to be useful
+ # when implementing a real-world config command!)
+
+ def check_func(self, func, headers=None, include_dirs=None,
+ libraries=None, library_dirs=None, decl=False, call=False):
+
+ """Determine if function 'func' is available by constructing a
+ source file that refers to 'func', and compiles and links it.
+ If everything succeeds, returns true; otherwise returns false.
+
+ The constructed source file starts out by including the header
+ files listed in 'headers'. If 'decl' is true, it then declares
+ 'func' (as "int func()"); you probably shouldn't supply 'headers'
+ and set 'decl' true in the same call, or you might get errors about
+ a conflicting declarations for 'func'. Finally, the constructed
+ 'main()' function either references 'func' or (if 'call' is true)
+ calls it. 'libraries' and 'library_dirs' are used when
+ linking.
+ """
+
+ self._check_compiler()
+ body = []
+ if decl:
+ body.append("int %s ();" % func)
+ body.append("int main () {")
+ if call:
+ body.append(" %s();" % func)
+ else:
+ body.append(" %s;" % func)
+ body.append("}")
+ body = "\n".join(body) + "\n"
+
+ return self.try_link(body, headers, include_dirs,
+ libraries, library_dirs)
+
+ def check_lib(self, library, library_dirs=None, headers=None,
+ include_dirs=None, other_libraries=[]):
+ """Determine if 'library' is available to be linked against,
+ without actually checking that any particular symbols are provided
+ by it. 'headers' will be used in constructing the source file to
+ be compiled, but the only effect of this is to check if all the
+ header files listed are available. Any libraries listed in
+ 'other_libraries' will be included in the link, in case 'library'
+ has symbols that depend on other libraries.
+ """
+ self._check_compiler()
+ return self.try_link("int main (void) { }",
+ headers, include_dirs,
+ [library]+other_libraries, library_dirs)
+
+ def check_header(self, header, include_dirs=None, library_dirs=None,
+ lang="c"):
+ """Determine if the system header file named by 'header_file'
+ exists and can be found by the preprocessor; return true if so,
+ false otherwise.
+ """
+ return self.try_cpp(body="/* No body */", headers=[header],
+ include_dirs=include_dirs)
+
+
+def dump_file(filename, head=None):
+ """Dumps a file content into log.info.
+
+ If head is not None, will be dumped before the file content.
+ """
+ if head is None:
+ logger.info(filename)
+ else:
+ logger.info(head)
+ with open(filename) as file:
+ logger.info(file.read())