1# SPDX-License-Identifier: GPL-2.0+ 2# Copyright (c) 2011 The Chromium OS Authors. 3# 4 5import os 6 7from u_boot_pylib import 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, stdout='', stderr='', combined='', return_code=0, 21 exception=None): 22 self.stdout = stdout 23 self.stderr = stderr 24 self.combined = combined 25 self.return_code = return_code 26 self.exception = exception 27 28 def to_output(self, binary): 29 if not binary: 30 self.stdout = self.stdout.decode('utf-8') 31 self.stderr = self.stderr.decode('utf-8') 32 self.combined = self.combined.decode('utf-8') 33 return self 34 35 36# This permits interception of RunPipe for test purposes. If it is set to 37# a function, then that function is called with the pipe list being 38# executed. Otherwise, it is assumed to be a CommandResult object, and is 39# returned as the result for every run_pipe() call. 40# When this value is None, commands are executed as normal. 41test_result = None 42 43def run_pipe(pipe_list, infile=None, outfile=None, 44 capture=False, capture_stderr=False, oneline=False, 45 raise_on_error=True, cwd=None, binary=False, 46 output_func=None, **kwargs): 47 """ 48 Perform a command pipeline, with optional input/output filenames. 49 50 Args: 51 pipe_list: List of command lines to execute. Each command line is 52 piped into the next, and is itself a list of strings. For 53 example [ ['ls', '.git'] ['wc'] ] will pipe the output of 54 'ls .git' into 'wc'. 55 infile: File to provide stdin to the pipeline 56 outfile: File to store stdout 57 capture: True to capture output 58 capture_stderr: True to capture stderr 59 oneline: True to strip newline chars from output 60 output_func: Output function to call with each output fragment 61 (if it returns True the function terminates) 62 kwargs: Additional keyword arguments to cros_subprocess.Popen() 63 Returns: 64 CommandResult object 65 """ 66 if test_result: 67 if hasattr(test_result, '__call__'): 68 # pylint: disable=E1102 69 result = test_result(pipe_list=pipe_list) 70 if result: 71 return result 72 else: 73 return test_result 74 # No result: fall through to normal processing 75 result = CommandResult(b'', b'', b'') 76 last_pipe = None 77 pipeline = list(pipe_list) 78 user_pipestr = '|'.join([' '.join(pipe) for pipe in pipe_list]) 79 kwargs['stdout'] = None 80 kwargs['stderr'] = None 81 while pipeline: 82 cmd = pipeline.pop(0) 83 if last_pipe is not None: 84 kwargs['stdin'] = last_pipe.stdout 85 elif infile: 86 kwargs['stdin'] = open(infile, 'rb') 87 if pipeline or capture: 88 kwargs['stdout'] = cros_subprocess.PIPE 89 elif outfile: 90 kwargs['stdout'] = open(outfile, 'wb') 91 if capture_stderr: 92 kwargs['stderr'] = cros_subprocess.PIPE 93 94 try: 95 last_pipe = cros_subprocess.Popen(cmd, cwd=cwd, **kwargs) 96 except Exception as err: 97 result.exception = err 98 if raise_on_error: 99 raise Exception("Error running '%s': %s" % (user_pipestr, str)) 100 result.return_code = 255 101 return result.to_output(binary) 102 103 if capture: 104 result.stdout, result.stderr, result.combined = ( 105 last_pipe.communicate_filter(output_func)) 106 if result.stdout and oneline: 107 result.output = result.stdout.rstrip(b'\r\n') 108 result.return_code = last_pipe.wait() 109 if raise_on_error and result.return_code: 110 raise Exception("Error running '%s'" % user_pipestr) 111 return result.to_output(binary) 112 113def output(*cmd, **kwargs): 114 kwargs['raise_on_error'] = kwargs.get('raise_on_error', True) 115 return run_pipe([cmd], capture=True, **kwargs).stdout 116 117def output_one_line(*cmd, **kwargs): 118 """Run a command and output it as a single-line string 119 120 The command us expected to produce a single line of output 121 122 Returns: 123 String containing output of command 124 """ 125 raise_on_error = kwargs.pop('raise_on_error', True) 126 result = run_pipe([cmd], capture=True, oneline=True, 127 raise_on_error=raise_on_error, **kwargs).stdout.strip() 128 return result 129 130def run(*cmd, **kwargs): 131 return run_pipe([cmd], **kwargs).stdout 132 133def run_list(cmd): 134 return run_pipe([cmd], capture=True).stdout 135 136def stop_all(): 137 cros_subprocess.stay_alive = False 138