def rotate_groups(self, max_backup_groups):
"""Rotates backup groups."""
try:
groups = []
for group in self.__groups(check = True, reverse = True):
try:
if self.backups(group, check = True, orig_error = True):
groups.append(group)
except EnvironmentError as e:
if e.errno == errno.ENOENT:
# Just in case: ignore race conditions
pass
else:
LOG.error(
"Error while rotating backup groups: "
"Unable to read backup group '%s': %s.",
group, psys.e(e))
for group in groups[max_backup_groups:]:
LOG.info("Removing backup group '%s'...", group)
shutil.rmtree(self.group_path(group),
onerror = lambda func, path, excinfo:
LOG.error("Failed to remove '%s': %s.", path, psys.e(excinfo[1])))
if not os.path.exists(self.group_path(group)):
self.__on_group_deleted(group)
except Exception as e:
LOG.error("Failed to rotate backup groups: %s", e)
def __wait_pid_thread(self, fork_lock, termination_fd):
"""Waits for the process termination."""
try:
# Wait for fork() process completion
with fork_lock:
pass
# Wait only if we've successfully forked
if self.__pid is None:
return
try:
status = eintr_retry(os.waitpid)(self.__pid, 0)[1]
except Exception as e:
LOG.error("Failed to waitpid() process %s: %s.", self.__pid, psys.e(e))
self.__status = 127
else:
if os.WIFEXITED(status):
self.__status = os.WEXITSTATUS(status)
LOG.debug("Command %s terminated with %s status code.", self, self.__status)
elif os.WIFSIGNALED(status):
signum = os.WTERMSIG(status)
LOG.debug("Command %s terminated due to receipt of %s signal.", self, signum)
self.__status = 128 + signum
else:
LOG.error("Command %s terminated due to unknown reason.", self)
self.__status = 127
except Exception:
LOG.exception("PID waiting thread crashed.")
finally:
try:
eintr_retry(os.close)(termination_fd)
except Exception as e:
LOG.error("Unable to close a pipe: %s.", psys.e(e))
def __restore_attributes(self, tar_info, path):
"""Restores all attributes of a restored file."""
if os.geteuid() == 0:
try:
try:
uid = utils.getpwnam(tar_info.uname)[2]
except KeyError:
uid = tar_info.uid
try:
gid = utils.getgrnam(tar_info.gname)[2]
except KeyError:
gid = tar_info.gid
os.lchown(path, uid, gid)
except Exception as e:
if not psys.is_errno(e, errno.ENOENT):
LOG.error("Failed to set owner of '%s': %s.", path, psys.e(e))
self.__ok = False
if not tar_info.issym():
try:
os.chmod(path, tar_info.mode)
except Exception as e:
if not psys.is_errno(e, errno.ENOENT):
LOG.error("Failed to change permissions of '%s': %s.", path, psys.e(e))
self.__ok = False
try:
os.utime(path, ( tar_info.mtime, tar_info.mtime ))
except Exception as e:
if not psys.is_errno(e, errno.ENOENT):
LOG.error("Failed to change access and modification time of '%s': %s.", path, psys.e(e))
self.__ok = False
def __decompress(self, path, compressed_file):
"""Decompresses a compressed tar archive."""
LOG.debug("Decompressing '%s'...", path)
try:
self.__temp_file = tempfile.NamedTemporaryFile(dir = "/var/tmp")
shutil.copyfileobj(compressed_file, self.__temp_file)
self.__temp_file.flush()
except BaseException as e:
if self.__temp_file is not None:
try:
self.__temp_file.close()
except Exception as e:
LOG.error("Failed to delete a temporary file '%s': %s.",
self.__temp_file.name, psys.e(e))
finally:
self.__temp_file = None
if not isinstance(e, Exception):
raise
LOG.error("Failed to decompress '%s': %s.", path, psys.e(e))
else:
LOG.debug("Decompressing finished.")
self.__file = tarfile.open(self.__temp_file.name)
def __execute(self, stdout):
"""Executes the command."""
# Configure the standard I/O file descriptors
self.__configure_stdio(stdout)
# Fork the process -->
fork_lock = threading.Lock()
with fork_lock:
# Allocate all resources before fork() to guarantee that we will
# be able to control the process execution.
# Execution thread -->
poll = psys.poll.Poll()
try:
self.__communication_thread = threading.Thread(
target=self.__communication_thread_func,
args=(fork_lock, poll))
self.__communication_thread.daemon = True
self.__communication_thread.start()
except:
poll.close()
raise
# Execution thread <--
# Wait thread -->
try:
self.__termination_fd, termination_fd = os.pipe()
except Exception as e:
raise Error("Unable to create a pipe: {0}.", psys.e(e))
try:
self.__wait_thread = threading.Thread(
target=self.__wait_pid_thread,
args=[fork_lock, termination_fd])
self.__wait_thread.daemon = True
self.__wait_thread.start()
except BaseException as error:
try:
eintr_retry(os.close)(termination_fd)
except Exception as e:
LOG.error("Unable to close a pipe: %s.", psys.e(e))
raise error
# Wait thread <--
self.__pid = os.fork()
if self.__pid:
self.__state = _PROCESS_STATE_RUNNING
else:
self.__child()
def __execute(self, stdout):
"""Executes the command."""
# Configure the standard I/O file descriptors
self.__configure_stdio(stdout)
# Fork the process -->
fork_lock = threading.Lock()
with fork_lock:
# Allocate all resources before fork() to guarantee that we will
# be able to control the process execution.
# Execution thread -->
poll = psys.poll.Poll()
try:
self.__communication_thread = threading.Thread(
target=self.__communication_thread_func,
args=(fork_lock, poll))
self.__communication_thread.daemon = True
self.__communication_thread.start()
except:
poll.close()
raise
# Execution thread <--
# Wait thread -->
try:
self.__termination_fd, termination_fd = os.pipe()
except Exception as e:
raise Error("Unable to create a pipe: {0}.", psys.e(e))
try:
self.__wait_thread = threading.Thread(
target=self.__wait_pid_thread, args=[fork_lock, termination_fd])
self.__wait_thread.daemon = True
self.__wait_thread.start()
except BaseException as error:
try:
eintr_retry(os.close)(termination_fd)
except Exception as e:
LOG.error("Unable to close a pipe: %s.", psys.e(e))
raise error
# Wait thread <--
self.__pid = os.fork()
if self.__pid:
self.__state = _PROCESS_STATE_RUNNING
else:
self.__child()
def _load_metadata(backup_path, handle_metadata):
"""Loads metadata of the specified backup."""
ok = False
metadata_path = os.path.join(backup_path, _METADATA_FILE_NAME)
LOG.debug("Loading backup metadata '%s'...", metadata_path)
try:
with bz2.BZ2File(metadata_path, mode = "r") as metadata_file:
for line in metadata_file:
line = line.rstrip(b"\r\n")
if not line:
continue
handle_metadata(*line.decode(_ENCODING).split(" ", 3))
ok = True
except Exception as e:
LOG.error("Failed to load backup metadata '%s': %s.", metadata_path, psys.e(e))
else:
LOG.debug("Backup metadata '%s' has been successfully loaded.", metadata_path)
return ok
def cancel_backup(self, group, name):
"""Cancels the specified backup."""
shutil.rmtree(
self.backup_path(group, name, temp = True),
onerror = lambda func, path, excinfo:
LOG.error("Failed to remove backup temporary data '%s': %s.",
path, psys.e(excinfo[1])))
def close(self, read=True, write=True):
"""Closes the pipe."""
if read and self.read is not None:
try:
eintr_retry(os.close)(self.read)
except Exception as e:
LOG.error("Unable to close a pipe: %s.", psys.e(e))
else:
self.read = None
if write and self.write is not None:
try:
eintr_retry(os.close)(self.write)
except Exception as e:
LOG.error("Unable to close a pipe: %s.", psys.e(e))
else:
self.write = None
def close(self, read=True, write=True):
"""Closes the pipe."""
if read and self.read is not None:
try:
eintr_retry(os.close)(self.read)
except Exception as e:
LOG.error("Unable to close a pipe: %s.", psys.e(e))
else:
self.read = None
if write and self.write is not None:
try:
eintr_retry(os.close)(self.write)
except Exception as e:
LOG.error("Unable to close a pipe: %s.", psys.e(e))
else:
self.write = None
def __backup_path(self, path, filters, toplevel):
"""Backups the specified path."""
ok = True
LOG.info("Backing up '%s'...", path)
try:
stat_info = os.lstat(path)
if stat.S_ISREG(stat_info.st_mode):
self.__backup_file(path)
else:
if stat.S_ISLNK(stat_info.st_mode):
try:
link_target = os.readlink(path)
except EnvironmentError as e:
if e.errno == errno.EINVAL:
raise FileTypeChangedError()
else:
raise
else:
link_target = None
self.__backup.add_file(
path, stat_info, link_target = link_target)
if stat.S_ISDIR(stat_info.st_mode):
prefix = toplevel + os.path.sep
for filename in os.listdir(path):
file_path = os.path.join(path, filename)
for allow, regex in filters:
if not file_path.startswith(prefix):
raise LogicalError()
if regex.search(file_path[len(prefix):]):
if allow:
self.__backup_path(file_path, filters, toplevel)
else:
LOG.info("Filtering out '%s'...", file_path)
break
else:
self.__backup_path(file_path, filters, toplevel)
except FileTypeChangedError as e:
LOG.error("Failed to backup '%s': it has suddenly changed its type during the backup.", path)
ok = False
except Exception as e:
if psys.is_errno(e, (errno.ENOENT, errno.ENOTDIR)) and path != toplevel:
LOG.warning("Failed to backup '%s': it has suddenly vanished.", path)
else:
LOG.error("Failed to backup '%s': %s.", path, psys.e(e))
ok = False
return ok
def close(self):
"""Closes the object."""
if self.__epoll is not None:
try:
eintr_retry(self.__epoll.close)()
except Exception as e:
LOG.error("Unable to close an epoll instance: %s.", psys.e(e))
else:
self.__epoll = None
def __close(self):
"""Closes all opened files."""
try:
if self.__data is not None:
try:
self.__data.close()
except Exception as e:
raise Error("Unable to close backup data file: {}.", psys.e(e))
finally:
self.__data = None
finally:
if self.__metadata is not None:
try:
self.__metadata.close()
except Exception as e:
raise Error("Unable to close backup metadata file: {}.", psys.e(e))
finally:
self.__metadata = None
def __load_all_backup_metadata(self, trust_modify_time):
"""Loads all metadata from previous backups."""
try:
backups = self.__storage.backups(self.__group, reverse = True)
for backup_id, backup in enumerate(backups):
self.__load_backup_metadata(backup,
with_prev_files_info = trust_modify_time and not backup_id)
except Exception as e:
LOG.error("Failed to load metadata from previous backups: %s.", psys.e(e))
def close(self):
"""Closes the object."""
if self.__epoll is not None:
try:
eintr_retry(self.__epoll.close)()
except Exception as e:
LOG.error("Unable to close an epoll instance: %s.",
psys.e(e))
else:
self.__epoll = None
def __groups(self, check = False, reverse = False):
"""Returns a list of all backup groups."""
try:
return sorted(
( group for group in os.listdir(self.__backup_root)
if ( _GROUP_NAME_RE.search(group) if check else not group.startswith(".") )),
reverse = reverse)
except EnvironmentError as e:
raise Error("Error while reading backup root directory '{}': {}.",
self.__backup_root, psys.e(e))
def __wait_pid_thread(self, fork_lock, termination_fd):
"""Waits for the process termination."""
try:
# Wait for fork() process completion
with fork_lock:
pass
# Wait only if we've successfully forked
if self.__pid is None:
return
try:
status = eintr_retry(os.waitpid)(self.__pid, 0)[1]
except Exception as e:
LOG.error("Failed to waitpid() process %s: %s.", self.__pid,
psys.e(e))
self.__status = 127
else:
if os.WIFEXITED(status):
self.__status = os.WEXITSTATUS(status)
LOG.debug("Command %s terminated with %s status code.",
self, self.__status)
elif os.WIFSIGNALED(status):
signum = os.WTERMSIG(status)
LOG.debug(
"Command %s terminated due to receipt of %s signal.",
self, signum)
self.__status = 128 + signum
else:
LOG.error("Command %s terminated due to unknown reason.",
self)
self.__status = 127
except Exception:
LOG.exception("PID waiting thread crashed.")
finally:
try:
eintr_retry(os.close)(termination_fd)
except Exception as e:
LOG.error("Unable to close a pipe: %s.", psys.e(e))
def __init__(self, backup_path, restore_path = None, in_place = False):
# Backup name
self.__name = None
# Backup group name
self.__group = None
# Backup data storage abstraction
self.__storage = None
# Restore path
self.__restore_path = restore_path
# Don't use extra disc space by decompressing backup files
self.__in_place = in_place
# Current object state
self.__state = _STATE_OPENED
# Data file
self.__data = None
# Extern files
self.__extern_files = {}
# All backups with extern files with cached metadata
self.__backups = []
# False if something went wrong during the restore
self.__ok = True
try:
LOG.info("Restoring backup '%s'...", backup_path)
self.__name, self.__group, self.__storage = Storage.create(backup_path)
if self.__restore_path is None:
self.__restore_path = self.__name
try:
self.__data = utils.CompressedTarFile(
os.path.join(backup_path, _DATA_FILE_NAME),
decompress = not self.__in_place)
except Exception as e:
raise Error("Unable to open data of '{}' backup: {}.",
backup_path, psys.e(e))
self.__init_metadata_cache()
except:
self.close()
raise
def commit_backup(self, group, name):
"""Commits written backup data."""
cur_path = self.backup_path(group, name, temp = True)
new_path = self.backup_path(group, name)
try:
os.rename(cur_path, new_path)
except Exception as e:
raise Error("Unable to rename backup data directory '{}' to '{}': {}.",
cur_path, new_path, psys.e(e))
self.__on_backup_created(group, name, new_path)
def redirect_fd(path, fd, write=True, append=False):
try:
if write:
file_fd = eintr_retry(os.open)(
path, os.O_WRONLY | os.O_CREAT | (os.O_APPEND if append else 0), 0o666)
else:
file_fd = eintr_retry(os.open)(path, os.O_RDONLY)
try:
eintr_retry(os.dup2)(file_fd, fd)
finally:
eintr_retry(os.close)(file_fd)
except Exception as e:
raise Error("Unable to redirect {0} to {1}: {2}",
fd_name[fd] if write else "'" + path + "'",
"'" + path + "'" if write else fd_name[fd], psys.e(e))
def backups(self, group, check = False, reverse = False, orig_error = False):
"""Returns a list of all backups from the specified group."""
group_path = self.group_path(group)
try:
return sorted(
( backup for backup in os.listdir(group_path)
if ( _BACKUP_NAME_RE.search(backup) if check else not backup.startswith(".") )),
reverse = reverse)
except EnvironmentError as e:
if orig_error:
raise e
else:
raise Error("Error while reading backup group directory '{}': {}.",
group_path, psys.e(e))
def __close(self):
"""
Frees all allocated resources unneeded after the process termination
or its failed execution.
"""
for pipe in self.__pipes:
pipe.close()
del self.__pipes[:]
if self.__termination_fd is not None:
try:
eintr_retry(os.close)(self.__termination_fd)
except Exception as e:
LOG.error("Unable to close a pipe: %s.", psys.e(e))
else:
self.__termination_fd = None
def __close(self):
"""
Frees all allocated resources unneeded after the process termination
or its failed execution.
"""
for pipe in self.__pipes:
pipe.close()
del self.__pipes[:]
if self.__termination_fd is not None:
try:
eintr_retry(os.close)(self.__termination_fd)
except Exception as e:
LOG.error("Unable to close a pipe: %s.", psys.e(e))
else:
self.__termination_fd = None
def __create_group(self):
"""Creates a new backup group."""
group = time.strftime(_GROUP_NAME_FORMAT, time.localtime())
LOG.info("Creating backup group '%s'.", group)
group_path = self.group_path(group)
try:
os.mkdir(group_path)
except EnvironmentError as e:
if e.errno != errno.EEXIST:
raise Error("Unable to create a new backup group '{}': {}.",
group_path, psys.e(e))
self.__on_group_created(group)
return group
def redirect_fd(path, fd, write=True, append=False):
try:
if write:
file_fd = eintr_retry(
os.open)(path, os.O_WRONLY | os.O_CREAT |
(os.O_APPEND if append else 0), 0o666)
else:
file_fd = eintr_retry(os.open)(path, os.O_RDONLY)
try:
eintr_retry(os.dup2)(file_fd, fd)
finally:
eintr_retry(os.close)(file_fd)
except Exception as e:
raise Error("Unable to redirect {0} to {1}: {2}",
fd_name[fd] if write else "'" + path + "'",
"'" + path + "'" if write else fd_name[fd],
psys.e(e))
def __backup_file(self, path):
"""Backups the specified file."""
try:
try:
fd = eintr_retry(os.open)(path, self.__open_flags)
except EnvironmentError as e:
# If O_NOATIME flag was specified, but the effective user ID
# of the caller did not match the owner of the file and the
# caller was not privileged (CAP_FOWNER), the EPERM will be
# returned.
if (
hasattr(os, "O_NOATIME") and e.errno == errno.EPERM and
self.__open_flags & os.O_NOATIME
):
# Just disable this flag on a first EPERM error
LOG.debug("Got EPERM error. Disabling O_NOATIME for file opening operations...")
self.__open_flags &= ~os.O_NOATIME
fd = eintr_retry(os.open)(path, self.__open_flags)
else:
raise
except EnvironmentError as e:
# When O_NOFOLLOW is specified, indicates that this is a
# symbolic link.
if e.errno == errno.ELOOP:
raise FileTypeChangedError()
else:
raise
try:
file_obj = os.fdopen(fd, "rb")
except:
try:
eintr_retry(os.close)(fd)
except Exception as e:
LOG.error("Unable to close a file: %s.", psys.e(e))
raise
with file_obj:
stat_info = os.fstat(file_obj.fileno())
self.__backup.add_file(path, stat_info, file_obj = file_obj)
def __init__(self, source, output=True, pipe=None):
# File descriptor that we are going to replace by this pipe
self.source = source
# True if this is output file descriptor
self.output = output
if pipe is None:
try:
self.read, self.write = os.pipe()
except Exception as e:
raise Error("Unable to create a pipe: {0}.", psys.e(e))
else:
if output:
self.read = None
self.write = pipe.write
pipe.write = None
else:
self.read = pipe.read
pipe.read = None
self.write = None
def close(self):
"""Closes the object."""
if self.__state == _STATE_CLOSED:
return
try:
if (
self.__name is not None and
self.__group is not None and
self.__state != _STATE_COMMITTED
):
try:
self.__close()
except Exception as e:
LOG.error("Failed to close '%s' backup object: %s",
self.__name, psys.e(e))
self.__storage.cancel_backup(self.__group, self.__name)
finally:
self.__state = _STATE_CLOSED
def __init__(self, source, output=True, pipe=None):
# File descriptor that we are going to replace by this pipe
self.source = source
# True if this is output file descriptor
self.output = output
if pipe is None:
try:
self.read, self.write = os.pipe()
except Exception as e:
raise Error("Unable to create a pipe: {0}.", psys.e(e))
else:
if output:
self.read = None
self.write = pipe.write
pipe.write = None
else:
self.read = pipe.read
pipe.read = None
self.write = None
def __load_backup_data(self, name, hashes, paths):
"""Loads the specified backup's data."""
files = {}
data = None
backup_path = self.__storage.backup_path(self.__group, name)
LOG.debug("Loading data of '%s' backup...", backup_path)
try:
if name == self.__name:
data = self.__data
else:
data = utils.CompressedTarFile(
os.path.join(backup_path, _DATA_FILE_NAME),
decompress = not self.__in_place)
for tar_info in data:
hash = paths.get("/" + tar_info.name)
if hash is not None and hash in hashes:
files[hash] = tar_info
except Exception as e:
LOG.error("Failed to load data of '%s' backup: %s.", backup_path, psys.e(e))
else:
LOG.debug("Data of '%s' backup has been successfully loaded.", backup_path)
if files:
return {
"name": name,
"files": files,
"data": data,
}
else:
if data is not None and data is not self.__data:
try:
data.close()
except Exception as e:
LOG.error("Failed to close data file of '%s' backup: %s.", backup_path, e)
return None
def create_backup(self, max_backups):
"""Creates a new backup."""
name = time.strftime(_BACKUP_NAME_FORMAT, time.localtime())
LOG.info("Creating a new backup '%s'.", name)
groups = self.__groups()
if groups and len(self.backups(groups[-1], check = True)) < max_backups:
group = groups[-1]
LOG.info("Using backup group %s.", group)
else:
group = self.__create_group()
backup_path = self.backup_path(group, name, temp = True)
try:
os.mkdir(backup_path)
except Exception as e:
raise Error("Unable to create a backup directory '{}': {}.",
backup_path, psys.e(e))
return group, name, backup_path
def backup(self):
"""Starts the backup."""
try:
for path, params in self.__config["backup_items"].items():
if self.__run_script(params.get("before")):
try:
self.__add_toplevel_dirs(path)
except Exception as e:
LOG.error("Failed to backup '%s': %s.", path, psys.e(e))
self.__ok = False
else:
self.__ok &= self.__backup_path(path, params.get("filter", []), path)
self.__ok &= self.__run_script(params.get("after"))
else:
self.__ok = False
self.__backup.commit()
finally:
self.__backup.close()
return self.__ok
def restore(self, paths_to_restore = None):
"""Restores the backup.
Returns True if all files has been successfully restored.
"""
if self.__state != _STATE_OPENED:
raise Error("The backup file is closed.")
try:
os.mkdir(self.__restore_path, 0o700)
except Exception as e:
raise Error("Unable to create restore directory '{}': {}.",
self.__restore_path, psys.e(e))
files = []
LOG.debug("Loading the backup's data...")
try:
for tar_info in self.__data:
files.append(tar_info)
except Exception as e:
LOG.error("Failed to load the backup's data: %s.", psys.e(e))
self.__ok = False
else:
LOG.debug("The backup's data has been successfully loaded")
directories = []
for tar_info in files:
path = "/" + tar_info.name
if paths_to_restore is not None:
for path_to_restore in paths_to_restore:
if path == path_to_restore or path.startswith(path_to_restore + os.path.sep):
break
else:
continue
restore_path = os.path.join(self.__restore_path, tar_info.name)
LOG.info("Restoring '%s'...", path)
try:
if tar_info.isdir():
os.makedirs(restore_path, mode = 0o700)
directories.append(tar_info)
elif tar_info.islnk():
target_path = os.path.join(self.__restore_path, tar_info.linkname)
try:
os.link(target_path, restore_path)
except Exception as e:
raise Error("Unable to create a hard link to '{}': {}.", target_path, psys.e(e))
else:
extern_hash = self.__extern_files.get(path) if tar_info.isreg() else None
try:
if extern_hash is None:
try:
self.__data.extract(tar_info,
path = self.__restore_path, set_attrs = False)
except Exception as e:
raise Error("Unable to extract the file from backup: {}.", psys.e(e))
else:
self.__restore_extern_file(tar_info, extern_hash)
finally:
self.__restore_attributes(tar_info, restore_path)
except Exception as e:
LOG.error("Failed to restore '%s': %s", path, psys.e(e))
self.__ok = False
directories.sort(key = lambda tar_info: tar_info.name, reverse = True)
for tar_info in directories:
self.__restore_attributes(tar_info,
os.path.join(self.__restore_path, tar_info.name))
return self.__ok
def __child(self):
"""Handles child process execution."""
exit_code = 127
try:
exec_error = False
try:
fd_name = {
0: "stdin",
1: "stdout",
2: "stderr",
}
def redirect_fd(path, fd, write=True, append=False):
try:
if write:
file_fd = eintr_retry(os.open)(
path, os.O_WRONLY | os.O_CREAT | (os.O_APPEND if append else 0), 0o666)
else:
file_fd = eintr_retry(os.open)(path, os.O_RDONLY)
try:
eintr_retry(os.dup2)(file_fd, fd)
finally:
eintr_retry(os.close)(file_fd)
except Exception as e:
raise Error("Unable to redirect {0} to {1}: {2}",
fd_name[fd] if write else "'" + path + "'",
"'" + path + "'" if write else fd_name[fd], psys.e(e))
# Connect all pipes
for pipe in self.__pipes:
try:
eintr_retry(os.dup2)(pipe.write if pipe.output else pipe.read, pipe.source)
except Exception as e:
raise Error("Unable to connect a pipe to {0}: {1}",
fd_name[pipe.source], psys.e(e))
pipe.close()
# Close all file descriptors
psys.close_all_fds()
# Configure stdin
if isinstance(self.__stdin_source, File):
redirect_fd(self.__stdin_source.path, psys.STDIN_FILENO, write=False)
# Configure stdout
if self.__stdout_target is STDERR:
try:
eintr_retry(os.dup2)(psys.STDERR_FILENO, psys.STDOUT_FILENO)
except Exception as e:
raise Error("Unable to redirect stderr to stdout: {0}", psys.e(e))
elif isinstance(self.__stdout_target, File):
redirect_fd(self.__stdout_target.path, psys.STDOUT_FILENO,
append=self.__stdout_target.append)
# Configure stderr
if self.__stderr_target is STDOUT:
try:
eintr_retry(os.dup2)(psys.STDOUT_FILENO, psys.STDERR_FILENO)
except Exception as e:
raise Error("Unable to redirect stderr to stdout: {0}", psys.e(e))
elif isinstance(self.__stderr_target, File):
redirect_fd(self.__stderr_target.path, psys.STDERR_FILENO,
append=self.__stderr_target.append)
# Required when we have C locale
command = [psys.b(arg) for arg in self.__command]
exec_error = True
if self.__env is None:
os.execvp(self.__program, command)
else:
os.execvpe(self.__program, command, self.__env)
except Exception as e:
if exec_error and isinstance(e, EnvironmentError) and e.errno == errno.EACCES:
exit_code = 126
print("Failed to execute '{program}': {error}.".format(
program=self.__program, error=psys.e(e)), file=sys.stderr)
finally:
os._exit(exit_code)
def __child(self):
"""Handles child process execution."""
exit_code = 127
try:
exec_error = False
try:
fd_name = {
0: "stdin",
1: "stdout",
2: "stderr",
}
def redirect_fd(path, fd, write=True, append=False):
try:
if write:
file_fd = eintr_retry(
os.open)(path, os.O_WRONLY | os.O_CREAT |
(os.O_APPEND if append else 0), 0o666)
else:
file_fd = eintr_retry(os.open)(path, os.O_RDONLY)
try:
eintr_retry(os.dup2)(file_fd, fd)
finally:
eintr_retry(os.close)(file_fd)
except Exception as e:
raise Error("Unable to redirect {0} to {1}: {2}",
fd_name[fd] if write else "'" + path + "'",
"'" + path + "'" if write else fd_name[fd],
psys.e(e))
# Connect all pipes
for pipe in self.__pipes:
try:
eintr_retry(
os.dup2)(pipe.write if pipe.output else pipe.read,
pipe.source)
except Exception as e:
raise Error("Unable to connect a pipe to {0}: {1}",
fd_name[pipe.source], psys.e(e))
pipe.close()
# Close all file descriptors
psys.close_all_fds()
# Configure stdin
if isinstance(self.__stdin_source, File):
redirect_fd(self.__stdin_source.path,
psys.STDIN_FILENO,
write=False)
# Configure stdout
if self.__stdout_target is STDERR:
try:
eintr_retry(os.dup2)(psys.STDERR_FILENO,
psys.STDOUT_FILENO)
except Exception as e:
raise Error("Unable to redirect stdout to stderr: {0}",
psys.e(e))
elif isinstance(self.__stdout_target, File):
redirect_fd(self.__stdout_target.path,
psys.STDOUT_FILENO,
append=self.__stdout_target.append)
# Configure stderr
if self.__stderr_target is STDOUT:
try:
eintr_retry(os.dup2)(psys.STDOUT_FILENO,
psys.STDERR_FILENO)
except Exception as e:
raise Error("Unable to redirect stderr to stdout: {0}",
psys.e(e))
elif isinstance(self.__stderr_target, File):
redirect_fd(self.__stderr_target.path,
psys.STDERR_FILENO,
append=self.__stderr_target.append)
# Required when we have C locale
command = [psys.b(arg) for arg in self.__command]
exec_error = True
if self.__env is None:
os.execvp(self.__program, command)
else:
os.execvpe(self.__program, command, self.__env)
except Exception as e:
if exec_error and isinstance(
e, EnvironmentError) and e.errno == errno.EACCES:
exit_code = 126
print("Failed to execute '{program}': {error}.".format(
program=self.__program, error=psys.e(e)),
file=sys.stderr)
finally:
os._exit(exit_code)
def __init__(self, config, storage):
# Backup config
self.__config = config
# Backup storage abstraction
self.__storage = storage
# Backup name
self.__name = None
# Backup group
self.__group = None
# Current object state
self.__state = _STATE_OPENED
# Backup data file
self.__data = None
# Backup metadata file
self.__metadata = None
# A set of hashes of all available files in this backup group
self.__hashes = set()
# A map of files from the previous backup to their hashes and
# fingerprints.
self.__prev_files = {}
# A set of all files added to the backup
self.__files = set()
# Inodes of hard links added to the backup (to track hard-linked files)
self.__hardlink_inodes = {}
try:
self.__group, self.__name, path = self.__storage.create_backup(
self.__config["max_backups"])
self.__load_all_backup_metadata(self.__config["trust_modify_time"])
LOG.debug("Creating backup %s in group %s...", self.__name, self.__group)
try:
self.__data = utils.CompressedTarFile(
os.path.join(path, _DATA_FILE_NAME),
write = self.__config["compression"])
except Exception as e:
raise Error("Unable to create a backup data tar archive in '{}': {}.", path, psys.e(e))
metadata_path = os.path.join(path, _METADATA_FILE_NAME)
try:
self.__metadata = bz2.BZ2File(metadata_path, mode = "w")
except Exception as e:
raise Error("Unable to create a backup metadata file '{}': {}.",
metadata_path, psys.e(e))
except:
self.close()
raise
