builder.py

        Args:
            max_threads: Maximum number of threads we expect to need.
            setup_git: True to set up a git repo clone
        """
        builderthread.Mkdir(self._working_dir)
        for thread in range(max_threads):
            self._PrepareThread(thread, setup_git)

    def _PrepareOutputSpace(self):
        """Get the output directories ready to receive files.

        We delete any output directories which look like ones we need to
        create. Having left over directories is confusing when the user wants
        to check the output manually.
        """
        dir_list = []
        for commit_upto in range(self.commit_count):
            dir_list.append(self._GetOutputDir(commit_upto))

        for dirname in glob.glob(os.path.join(self.base_dir, '*')):
            if dirname not in dir_list:
                shutil.rmtree(dirname)

    def BuildBoards(self, commits, board_selected, keep_outputs, verbose):
        """Build all commits for a list of boards

        Args:
            commits: List of commits to be build, each a Commit object
            boards_selected: Dict of selected boards, key is target name,
                    value is Board object
            keep_outputs: True to save build output files
            verbose: Display build results as they are completed
        """
        self.commit_count = len(commits) if commits else 1
        self.commits = commits
        self._verbose = verbose

        self.ResetResultSummary(board_selected)
        builderthread.Mkdir(self.base_dir)
        self._PrepareWorkingSpace(min(self.num_threads, len(board_selected)),
                commits is not None)
        self._PrepareOutputSpace()
        self.SetupBuild(board_selected, commits)
        self.ProcessResult(None)

        # Create jobs to build all commits for each board
        for brd in board_selected.itervalues():
            job = builderthread.BuilderJob()
            job.board = brd
            job.commits = commits
            job.keep_outputs = keep_outputs
            job.step = self._step
            self.queue.put(job)

        # Wait until all jobs are started
        self.queue.join()

        # Wait until we have processed all output
        self.out_queue.join()
        print
        self.ClearLine(0)