diff options
Diffstat (limited to 'rdiff-backup/rdiff_backup/fs_abilities.py')
| -rw-r--r-- | rdiff-backup/rdiff_backup/fs_abilities.py | 264 |
1 files changed, 143 insertions, 121 deletions
diff --git a/rdiff-backup/rdiff_backup/fs_abilities.py b/rdiff-backup/rdiff_backup/fs_abilities.py index d303d7a..10cbb27 100644 --- a/rdiff-backup/rdiff_backup/fs_abilities.py +++ b/rdiff-backup/rdiff_backup/fs_abilities.py @@ -50,8 +50,8 @@ class FSAbilities: high_perms = None # True if suid etc perms are (read/write) supported escape_dos_devices = None # True if dos device files can't be created (e.g., # aux, con, com1, etc) - escape_trailing_spaces = None # True if files with trailing spaces or - # periods can't be created + escape_trailing_spaces = None # True if trailing spaces or periods at the + # end of filenames aren't preserved symlink_perms = None # True if symlink perms are affected by umask def __init__(self, name = None): @@ -131,7 +131,7 @@ class FSAbilities: self.set_carbonfile() self.set_case_sensitive_readonly(rp) self.set_escape_dos_devices(rp) - self.set_escape_trailing_spaces(rp) + self.set_escape_trailing_spaces_readonly(rp) return self def init_readwrite(self, rbdir): @@ -166,7 +166,7 @@ class FSAbilities: self.set_high_perms_readwrite(subdir) self.set_symlink_perms(subdir) self.set_escape_dos_devices(subdir) - self.set_escape_trailing_spaces(subdir) + self.set_escape_trailing_spaces_readwrite(subdir) subdir.delete() return self @@ -554,44 +554,88 @@ class FSAbilities: sym_source.delete() def set_escape_dos_devices(self, subdir): - """If special file con can be stat'd, escape special files""" + """Test if DOS device files can be used as filenames. + + This test must detect if the underlying OS is Windows, whehter we are + running under Cygwin or natively. Cygwin allows these special files to + be stat'd from any directory. Native Windows returns OSError (like + non-Cygwin POSIX), but we can check for that using os.name. + + Note that 'con' and 'aux' have some unusual behaviors as shown below. + + os.lstat() | con aux prn + -------------+------------------------------------- + Unix | OSError,2 OSError,2 OSError,2 + Cygwin/NTFS | -success- -success- -success- + Cygwin/FAT32 | -success- -HANGS- + Native Win | WinError,2 WinError,87 WinError,87 + """ + if os.name == "nt": + self.escape_dos_devices = 1 + return + try: device_rp = subdir.append("con") if device_rp.lstat(): - log.Log("escape_dos_devices required by filesystem at %s" \ - % (subdir.path), 4) self.escape_dos_devices = 1 else: - log.Log("escape_dos_devices not required by filesystem at %s" \ - % (subdir.path), 4) - self.escape_dos_devices = 0 + self.escape_dos_devices = 0 except(OSError): - log.Log("escape_dos_devices required by filesystem at %s" \ - % (subdir.path), 4) self.escape_dos_devices = 1 - def set_escape_trailing_spaces(self, subdir): - # Disable this for 1.2.4 - self.escape_trailing_spaces = 0 - return + def set_escape_trailing_spaces_readwrite(self, testdir): + """Windows and Linux/FAT32 will not preserve trailing spaces or periods. + + Linux/FAT32 behaves inconsistently: It will give an OSError,22 if + os.mkdir() is called on a directory name with a space at the end, but + will give an IOError("invalid mode") if you attempt to create a filename + with a space at the end. However, if a period is placed at the end of + the name, Linux/FAT32 is consistent with Cygwin and Native Windows. + """ - """If file with trailing space can't be created, escape such files""" - try: - space_rp = subdir.append("test ") - space_rp.touch() - if space_rp.lstat(): - log.Log("escape_trailing_spaces not required by filesystem " \ - "at %s" % (subdir.path), 4) - self.escape_trailing_spaces = 0 - space_rp.delete() - else: - log.Log("escape_trailing_spaces required by filesystem at %s" \ - % (subdir.path), 4) - self.escape_trailing_spaces = 1 - except (OSError, IOError): - log.Log("escape_trailing_spaces required by filesystem at %s" \ - % (subdir.path), 4) + period_rp = testdir.append("foo.") + assert not period_rp.lstat() + + tmp_rp = testdir.append("foo") + tmp_rp.touch() + assert tmp_rp.lstat() + + period_rp.setdata() + if period_rp.lstat(): self.escape_trailing_spaces = 1 + else: + self.escape_trailing_spaces = 0 + + tmp_rp.delete() + + def set_escape_trailing_spaces_readonly(self, rp): + """Determine if directory at rp permits filenames with trailing + spaces or periods without writing.""" + + def test_period(dir_rp, dirlist): + """Return 1 if trailing spaces and periods should be escaped""" + filename = dirlist[0] + try: + test_rp = dir_rp.append(filename) + except OSError: + return 0 + assert test_rp.lstat(), test_rp + period = filename + '.' + if period in dirlist: return 0 + + period_rp = dir_rp.append(period) + if period_rp.lstat(): return 1 + return 0 + + dirlist = robust.listrp(rp) + if len(dirlist): + self.escape_trailing_spaces = test_period(rp, dirlist) + else: + log.Log("Warning: could not determine if source directory at\n " + + rp.path + "\npermits trailing spaces or periods in " + "filenames because we can't find any files.\n" + "It will be treated as permitting such files.", 2) + self.escape_trailing_spaces = 0 def get_readonly_fsa(desc_string, rp): @@ -665,14 +709,6 @@ class SetGlobals: SetConnections.UpdateGlobal('symlink_perms', self.dest_fsa.symlink_perms) - def set_escape_dos_devices(self): - SetConnections.UpdateGlobal('escape_dos_devices', \ - self.dest_fsa.escape_dos_devices) - - def set_escape_trailing_spaces(self): - SetConnections.UpdateGlobal('escape_trailing_spaces', \ - self.dest_fsa.escape_trailing_spaces) - class BackupSetGlobals(SetGlobals): """Functions for setting fsa related globals for backup session""" def update_triple(self, src_support, dest_support, attr_triple): @@ -687,43 +723,50 @@ class BackupSetGlobals(SetGlobals): SetConnections.UpdateGlobal(write_attr, 1) self.out_conn.Globals.set_local(conn_attr, 1) - def set_must_escape_dos_devices(self, rbdir): - """If local edd or src edd, then must escape """ - try: - device_rp = rbdir.append("con") - if device_rp.lstat(): local_edd = 1 - else: local_edd = 0 - except (OSError): local_edd = 1 - SetConnections.UpdateGlobal('must_escape_dos_devices', \ - self.src_fsa.escape_dos_devices or local_edd) - log.Log("Backup: must_escape_dos_devices = %d" % \ - (self.src_fsa.escape_dos_devices or local_edd), 4) - - def set_must_escape_trailing_spaces(self, rbdir): - """If local ets or src ets, then must escape """ - # Disable this for 1.2.4 - SetConnections.UpdateGlobal('must_escape_trailing_spaces', 0) - return + def set_special_escapes(self, rbdir): + """Escaping DOS devices and trailing periods/spaces works like + regular filename escaping. If only the destination requires it, + then we do it. Otherwise, it is not necessary, since the files + couldn't have been created in the first place. We also record + whether we have done it in order to handle the case where a + volume which was escaped is later restored by an OS that does + not require it.""" + + suggested_edd = (self.dest_fsa.escape_dos_devices and not \ + self.src_fsa.escape_dos_devices) + suggested_ets = (self.dest_fsa.escape_trailing_spaces and not \ + self.src_fsa.escape_trailing_spaces) + + se_rp = rbdir.append("special_escapes") + if not se_rp.lstat(): + actual_edd, actual_ets = suggested_edd, suggested_ets + se = "" + if actual_edd: se = se + "escape_dos_devices\n" + if actual_ets: se = se + "escape_trailing_spaces\n" + se_rp.write_string(se) + else: + se = se_rp.get_data().split("\n") + actual_edd = ("escape_dos_devices" in se) + actual_ets = ("escape_trailing_spaces" in se) - try: - space_rp = rbdir.append("test ") - space_rp.touch() - if space_rp.lstat(): - local_ets = 0 - space_rp.delete() - else: - local_ets = 1 - except (OSError, IOError): - local_ets = 1 - SetConnections.UpdateGlobal('must_escape_trailing_spaces', \ - self.src_fsa.escape_trailing_spaces or local_ets) - log.Log("Backup: must_escape_trailing_spaces = %d" % \ - (self.src_fsa.escape_trailing_spaces or local_ets), 4) + if actual_edd != suggested_edd and not suggested_edd: + log.Log("Warning: System no longer needs DOS devices escaped, " + "but we will retain for backwards compatibility.", 2) + if actual_ets != suggested_ets and not suggested_ets: + log.Log("Warning: System no longer needs trailing spaces or " + "periods escaped, but we will retain for backwards " + "compatibility.", 2) + + SetConnections.UpdateGlobal('escape_dos_devices', actual_edd) + log.Log("Backup: escape_dos_devices = %d" % actual_edd, 4) + + SetConnections.UpdateGlobal('escape_trailing_spaces', actual_ets) + log.Log("Backup: escape_trailing_spaces = %d" % actual_ets, 4) def set_chars_to_quote(self, rbdir, force): """Set chars_to_quote setting for backup session - Unlike the other options, the chars_to_quote setting also + Unlike most other options, the chars_to_quote setting also depends on the current settings in the rdiff-backup-data directory, not just the current fs features. @@ -818,45 +861,33 @@ class RestoreSetGlobals(SetGlobals): self.out_conn.Globals.set_local(write_attr, 1) if src_support: self.in_conn.Globals.set_local(conn_attr, 1) - def set_must_escape_dos_devices(self, rbdir): - """If local edd or src edd, then must escape """ - if getattr(self, "src_fsa", None) is not None: - src_edd = self.src_fsa.escape_dos_devices - else: src_edd = 0 - try: - device_rp = rbdir.append("con") - if device_rp.lstat(): local_edd = 1 - else: local_edd = 0 - except (OSError): local_edd = 1 - SetConnections.UpdateGlobal('must_escape_dos_devices', \ - src_edd or local_edd) - log.Log("Restore: must_escape_dos_devices = %d" % \ - (src_edd or local_edd), 4) - - def set_must_escape_trailing_spaces(self, rbdir): - """If local ets or src ets, then must escape """ - # Disable this for 1.2.4 - SetConnections.UpdateGlobal('must_escape_trailing_spaces', 0) - return - - if getattr(self, "src_fsa", None) is not None: - src_ets = self.src_fsa.escape_trailing_spaces + def set_special_escapes(self, rbdir): + """Set escape_dos_devices and escape_trailing_spaces from + rdiff-backup-data dir, just like chars_to_quote""" + se_rp = rbdir.append("special_escapes") + if se_rp.lstat(): + se = se_rp.get_data().split("\n") + actual_edd = ("escape_dos_devices" in se) + actual_ets = ("escape_trailing_spaces" in se) else: - src_ets = 0 - try: - space_rp = rbdir.append("test ") - space_rp.touch() - if space_rp.lstat(): - local_ets = 0 - space_rp.delete() + log.Log("Warning: special_escapes file not found,\n" + "will assume need to escape DOS devices and trailing " + "spaces based on file systems.", 2) + if getattr(self, "src_fsa", None) is not None: + actual_edd = (self.src_fsa.escape_dos_devices and not + self.dest_fsa.escape_dos_devices) + actual_ets = (self.src_fsa.escape_trailing_spaces and not + self.dest_fsa.escape_trailing_spaces) else: - local_ets = 1 - except (OSError, IOError): - local_ets = 1 - SetConnections.UpdateGlobal('must_escape_trailing_spaces', \ - src_ets or local_ets) - log.Log("Restore: must_escape_trailing_spaces = %d" % \ - (src_ets or local_ets), 4) + # Single filesystem operation + actual_edd = self.dest_fsa.escape_dos_devices + actual_ets = self.dest_fsa.escape_trailing_spaces + + SetConnections.UpdateGlobal('escape_dos_devices', actual_edd) + log.Log("Backup: escape_dos_devices = %d" % actual_edd, 4) + + SetConnections.UpdateGlobal('escape_trailing_spaces', actual_ets) + log.Log("Backup: escape_trailing_spaces = %d" % actual_ets, 4) def set_chars_to_quote(self, rbdir): """Set chars_to_quote from rdiff-backup-data dir""" @@ -931,10 +962,7 @@ def backup_set_globals(rpin, force): bsg.set_high_perms() bsg.set_symlink_perms() update_quoting = bsg.set_chars_to_quote(Globals.rbdir, force) - bsg.set_escape_dos_devices() - bsg.set_escape_trailing_spaces() - bsg.set_must_escape_dos_devices(Globals.rbdir) - bsg.set_must_escape_trailing_spaces(Globals.rbdir) + bsg.set_special_escapes(Globals.rbdir) if update_quoting and force: FilenameMapping.update_quoting(Globals.rbdir) @@ -961,10 +989,7 @@ def restore_set_globals(rpout): rsg.set_high_perms() rsg.set_symlink_perms() rsg.set_chars_to_quote(Globals.rbdir) - rsg.set_escape_dos_devices() - rsg.set_escape_trailing_spaces() - rsg.set_must_escape_dos_devices(Globals.rbdir) - rsg.set_must_escape_trailing_spaces(Globals.rbdir) + rsg.set_special_escapes(Globals.rbdir) def single_set_globals(rp, read_only = None): """Set fsa related globals for operation on single filesystem""" @@ -984,8 +1009,5 @@ def single_set_globals(rp, read_only = None): ssg.set_high_perms() ssg.set_symlink_perms() ssg.set_chars_to_quote(Globals.rbdir) - ssg.set_escape_dos_devices() - ssg.set_escape_trailing_spaces() - ssg.set_must_escape_dos_devices(Globals.rbdir) - ssg.set_must_escape_trailing_spaces(Globals.rbdir) + ssg.set_special_escapes(Globals.rbdir) |