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Diffstat (limited to 'lib/python2.7/shutil.py')
| -rw-r--r-- | lib/python2.7/shutil.py | 565 |
1 files changed, 565 insertions, 0 deletions
diff --git a/lib/python2.7/shutil.py b/lib/python2.7/shutil.py new file mode 100644 index 0000000..388906f --- /dev/null +++ b/lib/python2.7/shutil.py @@ -0,0 +1,565 @@ +"""Utility functions for copying and archiving files and directory trees. + +XXX The functions here don't copy the resource fork or other metadata on Mac. + +""" + +import os +import sys +import stat +from os.path import abspath +import fnmatch +import collections +import errno + +try: + from pwd import getpwnam +except ImportError: + getpwnam = None + +try: + from grp import getgrnam +except ImportError: + getgrnam = None + +__all__ = ["copyfileobj", "copyfile", "copymode", "copystat", "copy", "copy2", + "copytree", "move", "rmtree", "Error", "SpecialFileError", + "ExecError", "make_archive", "get_archive_formats", + "register_archive_format", "unregister_archive_format", + "ignore_patterns"] + +class Error(EnvironmentError): + pass + +class SpecialFileError(EnvironmentError): + """Raised when trying to do a kind of operation (e.g. copying) which is + not supported on a special file (e.g. a named pipe)""" + +class ExecError(EnvironmentError): + """Raised when a command could not be executed""" + +try: + WindowsError +except NameError: + WindowsError = None + +def copyfileobj(fsrc, fdst, length=16*1024): + """copy data from file-like object fsrc to file-like object fdst""" + while 1: + buf = fsrc.read(length) + if not buf: + break + fdst.write(buf) + +def _samefile(src, dst): + # Macintosh, Unix. + if hasattr(os.path, 'samefile'): + try: + return os.path.samefile(src, dst) + except OSError: + return False + + # All other platforms: check for same pathname. + return (os.path.normcase(os.path.abspath(src)) == + os.path.normcase(os.path.abspath(dst))) + +def copyfile(src, dst): + """Copy data from src to dst""" + if _samefile(src, dst): + raise Error("`%s` and `%s` are the same file" % (src, dst)) + + for fn in [src, dst]: + try: + st = os.stat(fn) + except OSError: + # File most likely does not exist + pass + else: + # XXX What about other special files? (sockets, devices...) + if stat.S_ISFIFO(st.st_mode): + raise SpecialFileError("`%s` is a named pipe" % fn) + + with open(src, 'rb') as fsrc: + with open(dst, 'wb') as fdst: + copyfileobj(fsrc, fdst) + +def copymode(src, dst): + """Copy mode bits from src to dst""" + if hasattr(os, 'chmod'): + st = os.stat(src) + mode = stat.S_IMODE(st.st_mode) + os.chmod(dst, mode) + +def copystat(src, dst): + """Copy all stat info (mode bits, atime, mtime, flags) from src to dst""" + st = os.stat(src) + mode = stat.S_IMODE(st.st_mode) + if hasattr(os, 'utime'): + os.utime(dst, (st.st_atime, st.st_mtime)) + if hasattr(os, 'chmod'): + os.chmod(dst, mode) + if hasattr(os, 'chflags') and hasattr(st, 'st_flags'): + try: + os.chflags(dst, st.st_flags) + except OSError, why: + for err in 'EOPNOTSUPP', 'ENOTSUP': + if hasattr(errno, err) and why.errno == getattr(errno, err): + break + else: + raise + +def copy(src, dst): + """Copy data and mode bits ("cp src dst"). + + The destination may be a directory. + + """ + if os.path.isdir(dst): + dst = os.path.join(dst, os.path.basename(src)) + copyfile(src, dst) + copymode(src, dst) + +def copy2(src, dst): + """Copy data and all stat info ("cp -p src dst"). + + The destination may be a directory. + + """ + if os.path.isdir(dst): + dst = os.path.join(dst, os.path.basename(src)) + copyfile(src, dst) + copystat(src, dst) + +def ignore_patterns(*patterns): + """Function that can be used as copytree() ignore parameter. + + Patterns is a sequence of glob-style patterns + that are used to exclude files""" + def _ignore_patterns(path, names): + ignored_names = [] + for pattern in patterns: + ignored_names.extend(fnmatch.filter(names, pattern)) + return set(ignored_names) + return _ignore_patterns + +def copytree(src, dst, symlinks=False, ignore=None): + """Recursively copy a directory tree using copy2(). + + The destination directory must not already exist. + If exception(s) occur, an Error is raised with a list of reasons. + + If the optional symlinks flag is true, symbolic links in the + source tree result in symbolic links in the destination tree; if + it is false, the contents of the files pointed to by symbolic + links are copied. + + The optional ignore argument is a callable. If given, it + is called with the `src` parameter, which is the directory + being visited by copytree(), and `names` which is the list of + `src` contents, as returned by os.listdir(): + + callable(src, names) -> ignored_names + + Since copytree() is called recursively, the callable will be + called once for each directory that is copied. It returns a + list of names relative to the `src` directory that should + not be copied. + + XXX Consider this example code rather than the ultimate tool. + + """ + names = os.listdir(src) + if ignore is not None: + ignored_names = ignore(src, names) + else: + ignored_names = set() + + os.makedirs(dst) + errors = [] + for name in names: + if name in ignored_names: + continue + srcname = os.path.join(src, name) + dstname = os.path.join(dst, name) + try: + if symlinks and os.path.islink(srcname): + linkto = os.readlink(srcname) + os.symlink(linkto, dstname) + elif os.path.isdir(srcname): + copytree(srcname, dstname, symlinks, ignore) + else: + # Will raise a SpecialFileError for unsupported file types + copy2(srcname, dstname) + # catch the Error from the recursive copytree so that we can + # continue with other files + except Error, err: + errors.extend(err.args[0]) + except EnvironmentError, why: + errors.append((srcname, dstname, str(why))) + try: + copystat(src, dst) + except OSError, why: + if WindowsError is not None and isinstance(why, WindowsError): + # Copying file access times may fail on Windows + pass + else: + errors.append((src, dst, str(why))) + if errors: + raise Error, errors + +def rmtree(path, ignore_errors=False, onerror=None): + """Recursively delete a directory tree. + + If ignore_errors is set, errors are ignored; otherwise, if onerror + is set, it is called to handle the error with arguments (func, + path, exc_info) where func is os.listdir, os.remove, or os.rmdir; + path is the argument to that function that caused it to fail; and + exc_info is a tuple returned by sys.exc_info(). If ignore_errors + is false and onerror is None, an exception is raised. + + """ + if ignore_errors: + def onerror(*args): + pass + elif onerror is None: + def onerror(*args): + raise + try: + if os.path.islink(path): + # symlinks to directories are forbidden, see bug #1669 + raise OSError("Cannot call rmtree on a symbolic link") + except OSError: + onerror(os.path.islink, path, sys.exc_info()) + # can't continue even if onerror hook returns + return + names = [] + try: + names = os.listdir(path) + except os.error, err: + onerror(os.listdir, path, sys.exc_info()) + for name in names: + fullname = os.path.join(path, name) + try: + mode = os.lstat(fullname).st_mode + except os.error: + mode = 0 + if stat.S_ISDIR(mode): + rmtree(fullname, ignore_errors, onerror) + else: + try: + os.remove(fullname) + except os.error, err: + onerror(os.remove, fullname, sys.exc_info()) + try: + os.rmdir(path) + except os.error: + onerror(os.rmdir, path, sys.exc_info()) + + +def _basename(path): + # A basename() variant which first strips the trailing slash, if present. + # Thus we always get the last component of the path, even for directories. + sep = os.path.sep + (os.path.altsep or '') + return os.path.basename(path.rstrip(sep)) + +def move(src, dst): + """Recursively move a file or directory to another location. This is + similar to the Unix "mv" command. + + If the destination is a directory or a symlink to a directory, the source + is moved inside the directory. The destination path must not already + exist. + + If the destination already exists but is not a directory, it may be + overwritten depending on os.rename() semantics. + + If the destination is on our current filesystem, then rename() is used. + Otherwise, src is copied to the destination and then removed. + A lot more could be done here... A look at a mv.c shows a lot of + the issues this implementation glosses over. + + """ + real_dst = dst + if os.path.isdir(dst): + if _samefile(src, dst): + # We might be on a case insensitive filesystem, + # perform the rename anyway. + os.rename(src, dst) + return + + real_dst = os.path.join(dst, _basename(src)) + if os.path.exists(real_dst): + raise Error, "Destination path '%s' already exists" % real_dst + try: + os.rename(src, real_dst) + except OSError: + if os.path.isdir(src): + if _destinsrc(src, dst): + raise Error, "Cannot move a directory '%s' into itself '%s'." % (src, dst) + copytree(src, real_dst, symlinks=True) + rmtree(src) + else: + copy2(src, real_dst) + os.unlink(src) + +def _destinsrc(src, dst): + src = abspath(src) + dst = abspath(dst) + if not src.endswith(os.path.sep): + src += os.path.sep + if not dst.endswith(os.path.sep): + dst += os.path.sep + return dst.startswith(src) + +def _get_gid(name): + """Returns a gid, given a group name.""" + if getgrnam is None or name is None: + return None + try: + result = getgrnam(name) + except KeyError: + result = None + if result is not None: + return result[2] + return None + +def _get_uid(name): + """Returns an uid, given a user name.""" + if getpwnam is None or name is None: + return None + try: + result = getpwnam(name) + except KeyError: + result = None + if result is not None: + return result[2] + return None + +def _make_tarball(base_name, base_dir, compress="gzip", verbose=0, dry_run=0, + owner=None, group=None, logger=None): + """Create a (possibly compressed) tar file from all the files under + 'base_dir'. + + 'compress' must be "gzip" (the default), "bzip2", or None. + + 'owner' and 'group' can be used to define an owner and a group for the + archive that is being built. If not provided, the current owner and group + will be used. + + The output tar file will be named 'base_name' + ".tar", possibly plus + the appropriate compression extension (".gz", or ".bz2"). + + Returns the output filename. + """ + tar_compression = {'gzip': 'gz', 'bzip2': 'bz2', None: ''} + compress_ext = {'gzip': '.gz', 'bzip2': '.bz2'} + + # flags for compression program, each element of list will be an argument + if compress is not None and compress not in compress_ext.keys(): + raise ValueError, \ + ("bad value for 'compress': must be None, 'gzip' or 'bzip2'") + + archive_name = base_name + '.tar' + compress_ext.get(compress, '') + archive_dir = os.path.dirname(archive_name) + + if archive_dir and not os.path.exists(archive_dir): + if logger is not None: + logger.info("creating %s", archive_dir) + if not dry_run: + os.makedirs(archive_dir) + + + # creating the tarball + import tarfile # late import so Python build itself doesn't break + + if logger is not None: + logger.info('Creating tar archive') + + uid = _get_uid(owner) + gid = _get_gid(group) + + def _set_uid_gid(tarinfo): + if gid is not None: + tarinfo.gid = gid + tarinfo.gname = group + if uid is not None: + tarinfo.uid = uid + tarinfo.uname = owner + return tarinfo + + if not dry_run: + tar = tarfile.open(archive_name, 'w|%s' % tar_compression[compress]) + try: + tar.add(base_dir, filter=_set_uid_gid) + finally: + tar.close() + + return archive_name + +def _call_external_zip(base_dir, zip_filename, verbose=False, dry_run=False): + # XXX see if we want to keep an external call here + if verbose: + zipoptions = "-r" + else: + zipoptions = "-rq" + from distutils.errors import DistutilsExecError + from distutils.spawn import spawn + try: + spawn(["zip", zipoptions, zip_filename, base_dir], dry_run=dry_run) + except DistutilsExecError: + # XXX really should distinguish between "couldn't find + # external 'zip' command" and "zip failed". + raise ExecError, \ + ("unable to create zip file '%s': " + "could neither import the 'zipfile' module nor " + "find a standalone zip utility") % zip_filename + +def _make_zipfile(base_name, base_dir, verbose=0, dry_run=0, logger=None): + """Create a zip file from all the files under 'base_dir'. + + The output zip file will be named 'base_name' + ".zip". Uses either the + "zipfile" Python module (if available) or the InfoZIP "zip" utility + (if installed and found on the default search path). If neither tool is + available, raises ExecError. Returns the name of the output zip + file. + """ + zip_filename = base_name + ".zip" + archive_dir = os.path.dirname(base_name) + + if archive_dir and not os.path.exists(archive_dir): + if logger is not None: + logger.info("creating %s", archive_dir) + if not dry_run: + os.makedirs(archive_dir) + + # If zipfile module is not available, try spawning an external 'zip' + # command. + try: + import zipfile + except ImportError: + zipfile = None + + if zipfile is None: + _call_external_zip(base_dir, zip_filename, verbose, dry_run) + else: + if logger is not None: + logger.info("creating '%s' and adding '%s' to it", + zip_filename, base_dir) + + if not dry_run: + with zipfile.ZipFile(zip_filename, "w", + compression=zipfile.ZIP_DEFLATED) as zf: + path = os.path.normpath(base_dir) + if path != os.curdir: + zf.write(path, path) + if logger is not None: + logger.info("adding '%s'", path) + for dirpath, dirnames, filenames in os.walk(base_dir): + for name in sorted(dirnames): + path = os.path.normpath(os.path.join(dirpath, name)) + zf.write(path, path) + if logger is not None: + logger.info("adding '%s'", path) + for name in filenames: + path = os.path.normpath(os.path.join(dirpath, name)) + if os.path.isfile(path): + zf.write(path, path) + if logger is not None: + logger.info("adding '%s'", path) + + return zip_filename + +_ARCHIVE_FORMATS = { + 'gztar': (_make_tarball, [('compress', 'gzip')], "gzip'ed tar-file"), + 'bztar': (_make_tarball, [('compress', 'bzip2')], "bzip2'ed tar-file"), + 'tar': (_make_tarball, [('compress', None)], "uncompressed tar file"), + 'zip': (_make_zipfile, [],"ZIP file") + } + +def get_archive_formats(): + """Returns a list of supported formats for archiving and unarchiving. + + Each element of the returned sequence is a tuple (name, description) + """ + formats = [(name, registry[2]) for name, registry in + _ARCHIVE_FORMATS.items()] + formats.sort() + return formats + +def register_archive_format(name, function, extra_args=None, description=''): + """Registers an archive format. + + name is the name of the format. function is the callable that will be + used to create archives. If provided, extra_args is a sequence of + (name, value) tuples that will be passed as arguments to the callable. + description can be provided to describe the format, and will be returned + by the get_archive_formats() function. + """ + if extra_args is None: + extra_args = [] + if not isinstance(function, collections.Callable): + raise TypeError('The %s object is not callable' % function) + if not isinstance(extra_args, (tuple, list)): + raise TypeError('extra_args needs to be a sequence') + for element in extra_args: + if not isinstance(element, (tuple, list)) or len(element) !=2 : + raise TypeError('extra_args elements are : (arg_name, value)') + + _ARCHIVE_FORMATS[name] = (function, extra_args, description) + +def unregister_archive_format(name): + del _ARCHIVE_FORMATS[name] + +def make_archive(base_name, format, root_dir=None, base_dir=None, verbose=0, + dry_run=0, owner=None, group=None, logger=None): + """Create an archive file (eg. zip or tar). + + 'base_name' is the name of the file to create, minus any format-specific + extension; 'format' is the archive format: one of "zip", "tar", "bztar" + or "gztar". + + 'root_dir' is a directory that will be the root directory of the + archive; ie. we typically chdir into 'root_dir' before creating the + archive. 'base_dir' is the directory where we start archiving from; + ie. 'base_dir' will be the common prefix of all files and + directories in the archive. 'root_dir' and 'base_dir' both default + to the current directory. Returns the name of the archive file. + + 'owner' and 'group' are used when creating a tar archive. By default, + uses the current owner and group. + """ + save_cwd = os.getcwd() + if root_dir is not None: + if logger is not None: + logger.debug("changing into '%s'", root_dir) + base_name = os.path.abspath(base_name) + if not dry_run: + os.chdir(root_dir) + + if base_dir is None: + base_dir = os.curdir + + kwargs = {'dry_run': dry_run, 'logger': logger} + + try: + format_info = _ARCHIVE_FORMATS[format] + except KeyError: + raise ValueError, "unknown archive format '%s'" % format + + func = format_info[0] + for arg, val in format_info[1]: + kwargs[arg] = val + + if format != 'zip': + kwargs['owner'] = owner + kwargs['group'] = group + + try: + filename = func(base_name, base_dir, **kwargs) + finally: + if root_dir is not None: + if logger is not None: + logger.debug("changing back to '%s'", save_cwd) + os.chdir(save_cwd) + + return filename |