"""Utility functions for copying 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 import os.path from os.path import abspath __all__ = ["copyfileobj","copyfile","copymode","copystat","copy","copy2", "copytree","move","rmtree","Error"] class Error(EnvironmentError): pass 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) fsrc = None fdst = None try: fsrc = open(src, 'rb') fdst = open(dst, 'wb') copyfileobj(fsrc, fdst) finally: if fdst: fdst.close() if fsrc: fsrc.close() 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 and mtime) 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) 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) try: copystat(src, dst) except OSError, (n, str): # can't change stats on ntfs partition even if # OS supports it if n == 1: pass else: raise Error, str def copytree(src, dst, symlinks=False): """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. XXX Consider this example code rather than the ultimate tool. """ names = os.listdir(src) os.makedirs(dst) errors = [] for name in names: 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) else: copy2(srcname, dstname) # XXX What about devices, sockets etc.? except (IOError, os.error), why: errors.append((srcname, dstname, str(why))) # catch the Error from the recursive copytree so that we can # continue with other files except Error, err: errors.extend(err.args[0]) try: copystat(src, dst) except OSError, (n, str): # can't change stats on ntfs partition even if # OS supports it if n == 1: pass else: errors.extend((src, dst, str)) except WindowsError: # can't copy file access times on Windows pass 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 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 move(src, dst): """Recursively move a file or directory to another location. If the destination is on our current filesystem, then simply use rename. Otherwise, copy src to the dst and then remove src. A lot more could be done here... A look at a mv.c shows a lot of the issues this implementation glosses over. """ try: os.rename(src, 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, dst, symlinks=True) rmtree(src) else: copy2(src,dst) os.unlink(src) def destinsrc(src, dst): return abspath(dst).startswith(abspath(src))