tools/u_boot_pylib/tout.py

   1 # SPDX-License-Identifier: GPL-2.0+
   2 # Copyright (c) 2016 Google, Inc
   3 #
   4 # Terminal output logging.
   5 #
   6
   7 import sys
   8
   9 from u_boot_pylib import terminal
  10
  11 # Output verbosity levels that we support
  12 ERROR, WARNING, NOTICE, INFO, DETAIL, DEBUG = range(6)
  13
  14 in_progress = False
  15
  16 """
  17 This class handles output of progress and other useful information
  18 to the user. It provides for simple verbosity level control and can
  19 output nothing but errors at verbosity zero.
  20
  21 The idea is that modules set up an Output object early in their years and pass
  22 it around to other modules that need it. This keeps the output under control
  23 of a single class.
  24
  25 Public properties:
  26     verbose: Verbosity level: 0=silent, 1=progress, 3=full, 4=debug
  27 """
  28 def __enter__():
  29     return
  30
  31 def __exit__(unused1, unused2, unused3):
  32     """Clean up and remove any progress message."""
  33     clear_progress()
  34     return False
  35
  36 def user_is_present():
  37     """This returns True if it is likely that a user is present.
  38
  39     Sometimes we want to prompt the user, but if no one is there then this
  40     is a waste of time, and may lock a script which should otherwise fail.
  41
  42     Returns:
  43         True if it thinks the user is there, and False otherwise
  44     """
  45     return stdout_is_tty and verbose > 0
  46
  47 def clear_progress():
  48     """Clear any active progress message on the terminal."""
  49     global in_progress
  50     if verbose > 0 and stdout_is_tty and in_progress:
  51         _stdout.write('\r%s\r' % (" " * len (_progress)))
  52         _stdout.flush()
  53         in_progress = False
  54
  55 def progress(msg, warning=False, trailer='...'):
  56     """Display progress information.
  57
  58     Args:
  59         msg: Message to display.
  60         warning: True if this is a warning."""
  61     global in_progress
  62     clear_progress()
  63     if verbose > 0:
  64         _progress = msg + trailer
  65         if stdout_is_tty:
  66             col = _color.YELLOW if warning else _color.GREEN
  67             _stdout.write('\r' + _color.build(col, _progress))
  68             _stdout.flush()
  69             in_progress = True
  70         else:
  71             _stdout.write(_progress + '\n')
  72
  73 def _output(level, msg, color=None):
  74     """Output a message to the terminal.
  75
  76     Args:
  77         level: Verbosity level for this message. It will only be displayed if
  78                 this as high as the currently selected level.
  79         msg; Message to display.
  80         error: True if this is an error message, else False.
  81     """
  82     if verbose >= level:
  83         clear_progress()
  84         if color:
  85             msg = _color.build(color, msg)
  86         if level < NOTICE:
  87             print(msg, file=sys.stderr)
  88         else:
  89             print(msg)
  90
  91 def do_output(level, msg):
  92     """Output a message to the terminal.
  93
  94     Args:
  95         level: Verbosity level for this message. It will only be displayed if
  96                 this as high as the currently selected level.
  97         msg; Message to display.
  98     """
  99     _output(level, msg)
 100
 101 def error(msg):
 102     """Display an error message
 103
 104     Args:
 105         msg; Message to display.
 106     """
 107     _output(ERROR, msg, _color.RED)
 108
 109 def warning(msg):
 110     """Display a warning message
 111
 112     Args:
 113         msg; Message to display.
 114     """
 115     _output(WARNING, msg, _color.YELLOW)
 116
 117 def notice(msg):
 118     """Display an important infomation message
 119
 120     Args:
 121         msg; Message to display.
 122     """
 123     _output(NOTICE, msg)
 124
 125 def info(msg):
 126     """Display an infomation message
 127
 128     Args:
 129         msg; Message to display.
 130     """
 131     _output(INFO, msg)
 132
 133 def detail(msg):
 134     """Display a detailed message
 135
 136     Args:
 137         msg; Message to display.
 138     """
 139     _output(DETAIL, msg)
 140
 141 def debug(msg):
 142     """Display a debug message
 143
 144     Args:
 145         msg; Message to display.
 146     """
 147     _output(DEBUG, msg)
 148
 149 def user_output(msg):
 150     """Display a message regardless of the current output level.
 151
 152     This is used when the output was specifically requested by the user.
 153     Args:
 154         msg; Message to display.
 155     """
 156     _output(0, msg)
 157
 158 def init(_verbose=WARNING, stdout=sys.stdout):
 159     """Initialize a new output object.
 160
 161     Args:
 162         verbose: Verbosity level (0-4).
 163         stdout: File to use for stdout.
 164     """
 165     global verbose, _progress, _color, _stdout, stdout_is_tty
 166
 167     verbose = _verbose
 168     _progress = ''                    # Our last progress message
 169     _color = terminal.Color()
 170     _stdout = stdout
 171
 172     # TODO(sjg): Move this into Chromite libraries when we have them
 173     stdout_is_tty = hasattr(sys.stdout, 'isatty') and sys.stdout.isatty()
 174     stderr_is_tty = hasattr(sys.stderr, 'isatty') and sys.stderr.isatty()
 175
 176 def uninit():
 177     clear_progress()
 178
 179 init()