| """distutils.file_util |
| |
| Utility functions for operating on single files. |
| """ |
| |
| 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 OSError as e: |
| raise DistutilsFileError("could not open '%s': %s" % (src, e.strerror)) |
| |
| if os.path.exists(dst): |
| try: |
| os.unlink(dst) |
| except OSError as e: |
| raise DistutilsFileError( |
| "could not delete '%s': %s" % (dst, e.strerror)) |
| |
| try: |
| fdst = open(dst, 'wb') |
| except OSError as e: |
| raise DistutilsFileError( |
| "could not create '%s': %s" % (dst, e.strerror)) |
| |
| while True: |
| try: |
| buf = fsrc.read(buffer_size) |
| except OSError as e: |
| raise DistutilsFileError( |
| "could not read from '%s': %s" % (src, e.strerror)) |
| |
| if not buf: |
| break |
| |
| try: |
| fdst.write(buf) |
| except OSError as e: |
| raise DistutilsFileError( |
| "could not write to '%s': %s" % (dst, e.strerror)) |
| 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) |
| elif 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 = False |
| try: |
| os.rename(src, dst) |
| except OSError as e: |
| (num, msg) = e.args |
| if num == errno.EXDEV: |
| copy_it = True |
| 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 OSError as e: |
| (num, msg) = e.args |
| try: |
| os.unlink(dst) |
| except OSError: |
| 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() |
