xref: /openbmc/u-boot/tools/patman/command.py (revision c2cde27d) 
1# Copyright (c) 2011 The Chromium OS Authors.
2#
3# SPDX-License-Identifier:	GPL-2.0+
4#
5
6import os
7import cros_subprocess
8
9"""Shell command ease-ups for Python."""
10
11class CommandResult:
12    """A class which captures the result of executing a command.
13
14    Members:
15        stdout: stdout obtained from command, as a string
16        stderr: stderr obtained from command, as a string
17        return_code: Return code from command
18        exception: Exception received, or None if all ok
19    """
20    def __init__(self):
21        self.stdout = None
22        self.stderr = None
23        self.return_code = None
24        self.exception = None
25
26
27def RunPipe(pipe_list, infile=None, outfile=None,
28            capture=False, capture_stderr=False, oneline=False,
29            raise_on_error=True, cwd=None, **kwargs):
30    """
31    Perform a command pipeline, with optional input/output filenames.
32
33    Args:
34        pipe_list: List of command lines to execute. Each command line is
35            piped into the next, and is itself a list of strings. For
36            example [ ['ls', '.git'] ['wc'] ] will pipe the output of
37            'ls .git' into 'wc'.
38        infile: File to provide stdin to the pipeline
39        outfile: File to store stdout
40        capture: True to capture output
41        capture_stderr: True to capture stderr
42        oneline: True to strip newline chars from output
43        kwargs: Additional keyword arguments to cros_subprocess.Popen()
44    Returns:
45        CommandResult object
46    """
47    result = CommandResult()
48    last_pipe = None
49    pipeline = list(pipe_list)
50    user_pipestr =  '|'.join([' '.join(pipe) for pipe in pipe_list])
51    while pipeline:
52        cmd = pipeline.pop(0)
53        if last_pipe is not None:
54            kwargs['stdin'] = last_pipe.stdout
55        elif infile:
56            kwargs['stdin'] = open(infile, 'rb')
57        if pipeline or capture:
58            kwargs['stdout'] = cros_subprocess.PIPE
59        elif outfile:
60            kwargs['stdout'] = open(outfile, 'wb')
61        if capture_stderr:
62            kwargs['stderr'] = cros_subprocess.PIPE
63
64        try:
65            last_pipe = cros_subprocess.Popen(cmd, cwd=cwd, **kwargs)
66        except Exception, err:
67            result.exception = err
68            if raise_on_error:
69                raise Exception("Error running '%s': %s" % (user_pipestr, str))
70            result.return_code = 255
71            return result
72
73    if capture:
74        result.stdout, result.stderr, result.combined = (
75                last_pipe.CommunicateFilter(None))
76        if result.stdout and oneline:
77            result.output = result.stdout.rstrip('\r\n')
78        result.return_code = last_pipe.wait()
79    else:
80        result.return_code = os.waitpid(last_pipe.pid, 0)[1]
81    if raise_on_error and result.return_code:
82        raise Exception("Error running '%s'" % user_pipestr)
83    return result
84
85def Output(*cmd):
86    return RunPipe([cmd], capture=True, raise_on_error=False).stdout
87
88def OutputOneLine(*cmd, **kwargs):
89    raise_on_error = kwargs.pop('raise_on_error', True)
90    return (RunPipe([cmd], capture=True, oneline=True,
91            raise_on_error=raise_on_error,
92            **kwargs).stdout.strip())
93
94def Run(*cmd, **kwargs):
95    return RunPipe([cmd], **kwargs).stdout
96
97def RunList(cmd):
98    return RunPipe([cmd], capture=True).stdout
99
100def StopAll():
101    cros_subprocess.stay_alive = False
102