| # Copyright 2013 Gentoo Foundation |
| # Distributed under the terms of the GNU General Public License v2 |
| |
| from portage import os |
| from portage.checksum import perform_multiple_checksums |
| from portage.util._async.ForkProcess import ForkProcess |
| from _emerge.PipeReader import PipeReader |
| |
| class FileDigester(ForkProcess): |
| """ |
| Asynchronously generate file digests. Pass in file_path and |
| hash_names, and after successful execution, the digests |
| attribute will be a dict containing all of the requested |
| digests. |
| """ |
| |
| __slots__ = ('file_path', 'digests', 'hash_names', |
| '_digest_pipe_reader', '_digest_pw') |
| |
| def _start(self): |
| pr, pw = os.pipe() |
| self.fd_pipes = {} |
| self.fd_pipes[pw] = pw |
| self._digest_pw = pw |
| self._digest_pipe_reader = PipeReader( |
| input_files={"input":pr}, |
| scheduler=self.scheduler) |
| self._digest_pipe_reader.addExitListener(self._digest_pipe_reader_exit) |
| self._digest_pipe_reader.start() |
| ForkProcess._start(self) |
| os.close(pw) |
| |
| def _run(self): |
| digests = perform_multiple_checksums(self.file_path, |
| hashes=self.hash_names) |
| |
| buf = "".join("%s=%s\n" % item |
| for item in digests.items()).encode('utf_8') |
| |
| while buf: |
| buf = buf[os.write(self._digest_pw, buf):] |
| |
| return os.EX_OK |
| |
| def _parse_digests(self, data): |
| |
| digests = {} |
| for line in data.decode('utf_8').splitlines(): |
| parts = line.split('=', 1) |
| if len(parts) == 2: |
| digests[parts[0]] = parts[1] |
| |
| self.digests = digests |
| |
| def _pipe_logger_exit(self, pipe_logger): |
| # Ignore this event, since we want to ensure that we |
| # exit only after _digest_pipe_reader has reached EOF. |
| self._pipe_logger = None |
| |
| def _digest_pipe_reader_exit(self, pipe_reader): |
| self._parse_digests(pipe_reader.getvalue()) |
| self._digest_pipe_reader = None |
| self._unregister() |
| self.wait() |
| |
| def _unregister(self): |
| ForkProcess._unregister(self) |
| |
| pipe_reader = self._digest_pipe_reader |
| if pipe_reader is not None: |
| self._digest_pipe_reader = None |
| pipe_reader.removeExitListener(self._digest_pipe_reader_exit) |
| pipe_reader.cancel() |
