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Diffstat (limited to 'lib/python2.7/distutils/file_util.py')
| -rw-r--r-- | lib/python2.7/distutils/file_util.py | 239 |
1 files changed, 239 insertions, 0 deletions
diff --git a/lib/python2.7/distutils/file_util.py b/lib/python2.7/distutils/file_util.py new file mode 100644 index 0000000..3b236e1 --- /dev/null +++ b/lib/python2.7/distutils/file_util.py @@ -0,0 +1,239 @@ +"""distutils.file_util + +Utility functions for operating on single files. +""" + +__revision__ = "$Id$" + +import os +from distutils.errors import DistutilsFileError +from distutils import log + +# for generating verbose output in 'copy_file()' +_copy_action = {None: 'copying', + 'hard': 'hard linking', + 'sym': 'symbolically linking'} + + +def _copy_file_contents(src, dst, buffer_size=16*1024): + """Copy the file 'src' to 'dst'. + + Both must be filenames. Any error opening either file, reading from + 'src', or writing to 'dst', raises DistutilsFileError. Data is + read/written in chunks of 'buffer_size' bytes (default 16k). No attempt + is made to handle anything apart from regular files. + """ + # Stolen from shutil module in the standard library, but with + # custom error-handling added. + fsrc = None + fdst = None + try: + try: + fsrc = open(src, 'rb') + except os.error, (errno, errstr): + raise DistutilsFileError("could not open '%s': %s" % (src, errstr)) + + if os.path.exists(dst): + try: + os.unlink(dst) + except os.error, (errno, errstr): + raise DistutilsFileError( + "could not delete '%s': %s" % (dst, errstr)) + + try: + fdst = open(dst, 'wb') + except os.error, (errno, errstr): + raise DistutilsFileError( + "could not create '%s': %s" % (dst, errstr)) + + while 1: + try: + buf = fsrc.read(buffer_size) + except os.error, (errno, errstr): + raise DistutilsFileError( + "could not read from '%s': %s" % (src, errstr)) + + if not buf: + break + + try: + fdst.write(buf) + except os.error, (errno, errstr): + raise DistutilsFileError( + "could not write to '%s': %s" % (dst, errstr)) + + finally: + if fdst: + fdst.close() + if fsrc: + fsrc.close() + +def copy_file(src, dst, preserve_mode=1, preserve_times=1, update=0, + link=None, verbose=1, dry_run=0): + """Copy a file 'src' to 'dst'. + + If 'dst' is a directory, then 'src' is copied there with the same name; + otherwise, it must be a filename. (If the file exists, it will be + ruthlessly clobbered.) If 'preserve_mode' is true (the default), + the file's mode (type and permission bits, or whatever is analogous on + the current platform) is copied. If 'preserve_times' is true (the + default), the last-modified and last-access times are copied as well. + If 'update' is true, 'src' will only be copied if 'dst' does not exist, + or if 'dst' does exist but is older than 'src'. + + 'link' allows you to make hard links (os.link) or symbolic links + (os.symlink) instead of copying: set it to "hard" or "sym"; if it is + None (the default), files are copied. Don't set 'link' on systems that + don't support it: 'copy_file()' doesn't check if hard or symbolic + linking is available. If hardlink fails, falls back to + _copy_file_contents(). + + Under Mac OS, uses the native file copy function in macostools; on + other systems, uses '_copy_file_contents()' to copy file contents. + + Return a tuple (dest_name, copied): 'dest_name' is the actual name of + the output file, and 'copied' is true if the file was copied (or would + have been copied, if 'dry_run' true). + """ + # XXX if the destination file already exists, we clobber it if + # copying, but blow up if linking. Hmmm. And I don't know what + # macostools.copyfile() does. Should definitely be consistent, and + # should probably blow up if destination exists and we would be + # changing it (ie. it's not already a hard/soft link to src OR + # (not update) and (src newer than dst). + + from distutils.dep_util import newer + from stat import ST_ATIME, ST_MTIME, ST_MODE, S_IMODE + + if not os.path.isfile(src): + raise DistutilsFileError( + "can't copy '%s': doesn't exist or not a regular file" % src) + + if os.path.isdir(dst): + dir = dst + dst = os.path.join(dst, os.path.basename(src)) + else: + dir = os.path.dirname(dst) + + if update and not newer(src, dst): + if verbose >= 1: + log.debug("not copying %s (output up-to-date)", src) + return dst, 0 + + try: + action = _copy_action[link] + except KeyError: + raise ValueError("invalid value '%s' for 'link' argument" % link) + + if verbose >= 1: + if os.path.basename(dst) == os.path.basename(src): + log.info("%s %s -> %s", action, src, dir) + else: + log.info("%s %s -> %s", action, src, dst) + + if dry_run: + return (dst, 1) + + # If linking (hard or symbolic), use the appropriate system call + # (Unix only, of course, but that's the caller's responsibility) + if link == 'hard': + if not (os.path.exists(dst) and os.path.samefile(src, dst)): + try: + os.link(src, dst) + return (dst, 1) + except OSError: + # If hard linking fails, fall back on copying file + # (some special filesystems don't support hard linking + # even under Unix, see issue #8876). + pass + elif link == 'sym': + if not (os.path.exists(dst) and os.path.samefile(src, dst)): + os.symlink(src, dst) + return (dst, 1) + + # Otherwise (non-Mac, not linking), copy the file contents and + # (optionally) copy the times and mode. + _copy_file_contents(src, dst) + if preserve_mode or preserve_times: + st = os.stat(src) + + # According to David Ascher <da@ski.org>, utime() should be done + # before chmod() (at least under NT). + if preserve_times: + os.utime(dst, (st[ST_ATIME], st[ST_MTIME])) + if preserve_mode: + os.chmod(dst, S_IMODE(st[ST_MODE])) + + return (dst, 1) + +# XXX I suspect this is Unix-specific -- need porting help! +def move_file (src, dst, verbose=1, dry_run=0): + """Move a file 'src' to 'dst'. + + If 'dst' is a directory, the file will be moved into it with the same + name; otherwise, 'src' is just renamed to 'dst'. Return the new + full name of the file. + + Handles cross-device moves on Unix using 'copy_file()'. What about + other systems??? + """ + from os.path import exists, isfile, isdir, basename, dirname + import errno + + if verbose >= 1: + log.info("moving %s -> %s", src, dst) + + if dry_run: + return dst + + if not isfile(src): + raise DistutilsFileError("can't move '%s': not a regular file" % src) + + if isdir(dst): + dst = os.path.join(dst, basename(src)) + elif exists(dst): + raise DistutilsFileError( + "can't move '%s': destination '%s' already exists" % + (src, dst)) + + if not isdir(dirname(dst)): + raise DistutilsFileError( + "can't move '%s': destination '%s' not a valid path" % \ + (src, dst)) + + copy_it = 0 + try: + os.rename(src, dst) + except os.error, (num, msg): + if num == errno.EXDEV: + copy_it = 1 + else: + raise DistutilsFileError( + "couldn't move '%s' to '%s': %s" % (src, dst, msg)) + + if copy_it: + copy_file(src, dst, verbose=verbose) + try: + os.unlink(src) + except os.error, (num, msg): + try: + os.unlink(dst) + except os.error: + pass + raise DistutilsFileError( + ("couldn't move '%s' to '%s' by copy/delete: " + + "delete '%s' failed: %s") % + (src, dst, src, msg)) + return dst + + +def write_file (filename, contents): + """Create a file with the specified name and write 'contents' (a + sequence of strings without line terminators) to it. + """ + f = open(filename, "w") + try: + for line in contents: + f.write(line + "\n") + finally: + f.close() |