def open(self, reopen_flag=False):
"""Open the given resource.
@param reopen_flag when True, attempt to reopen the same resource and check if it differs from the previously opened one.
@raise Exception if valid log_stream_fd was already provided, is still open and reopen_flag is False.
@raise OSError when opening failed with unexpected error.
@return True if the resource was really opened or False if opening was not yet possible but should be attempted again."""
if not reopen_flag and (self.log_file_fd != -1):
raise Exception('Cannot reopen stream still open when not instructed to do so')
log_file_fd = -1
stat_data = None
try:
log_file_fd = SecureOSFunctions.secure_open_file(self.log_resource_name[7:], os.O_RDONLY)
stat_data = os.fstat(log_file_fd)
except OSError as openOsError:
if log_file_fd != -1:
os.close(log_file_fd)
if openOsError.errno == errno.ENOENT:
return False
raise
if not stat.S_ISREG(stat_data.st_mode):
os.close(log_file_fd)
raise Exception('Attempting to open non-regular file %s as file' % encode_byte_string_as_string(self.log_resource_name))
if reopen_flag and (self.stat_data is not None) and (stat_data.st_ino == self.stat_data.st_ino) and (
stat_data.st_dev == self.stat_data.st_dev):
# Reopening was requested, but we would reopen the file already opened, which is of no use.
os.close(log_file_fd)
return False
# This is a new file or a successful reopen attempt.
self.log_file_fd = log_file_fd
self.stat_data = stat_data
return True
def open_persistence_file(file_name, flags):
"""This function opens the given persistence file. When O_CREAT was specified, the function will attempt to create the directories
too."""
if isinstance(file_name, str):
file_name = file_name.encode()
try:
fd = SecureOSFunctions.secure_open_file(file_name, flags)
return fd
except OSError as openOsError:
if ((flags & os.O_CREAT) == 0) or (openOsError.errno != errno.ENOENT):
raise openOsError
# Find out, which directory is missing by stating our way up.
dir_name_length = file_name.rfind(b'/')
if dir_name_length > 0:
os.makedirs(file_name[:dir_name_length])
return SecureOSFunctions.secure_open_file(file_name, flags)
def open_persistence_file(file_name, flags):
"""
Open the given persistence file.
When O_CREAT was specified, the function will attempt to create the directories too.
"""
if isinstance(file_name, str):
file_name = file_name.encode()
try:
fd = SecureOSFunctions.secure_open_file(file_name, flags)
return fd
except OSError as openOsError:
if ((flags & os.O_CREAT) == 0) or (openOsError.errno != errno.ENOENT):
logging.getLogger(DEBUG_LOG_NAME).error(openOsError)
raise openOsError
create_missing_directories(file_name)