src/python/command.py

   1 # Copyright (C) 2013-2020 Roland Lutz
   2 #
   3 # This program is free software; you can redistribute it and/or modify
   4 # it under the terms of the GNU General Public License as published by
   5 # the Free Software Foundation; either version 2 of the License, or
   6 # (at your option) any later version.
   7 #
   8 # This program is distributed in the hope that it will be useful,
   9 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  10 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11 # GNU General Public License for more details.
  12 #
  13 # You should have received a copy of the GNU General Public License
  14 # along with this program; if not, write to the Free Software Foundation,
  15 # Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  16
  17 ## \namespace xorn.command
  18 ## Infrastructure for \c xorn command-line scripts.
  19 #
  20 # This module provides some common functionality used by \c xorn
  21 # subcommands.  It is also where the \c xorn executable provides
  22 # information to submodules.
  23 #
  24 # A typical \c xorn subcommand looks like this:
  25 #
  26 # \code{.py}
  27 # #!/usr/bin/env python2.7
  28 # import xorn.command
  29 #
  30 # xorn.command.bugreport = 'example@example.com'
  31 #
  32 # def main():
  33 #     try:
  34 #         options, args = getopt.getopt(
  35 #             xorn.command.args, '', ['help', 'version'])
  36 #     except getopt.GetoptError as e:
  37 #         xorn.command.invalid_arguments(e.msg)
  38 #
  39 #     for option, value in options:
  40 #         # ... process options ...
  41 #
  42 #     # ... do something ...
  43 #
  44 # if __name__ == '__main__':
  45 #     main()
  46 # \endcode
  47
  48 import os.path, sys
  49 from gettext import gettext as _
  50 import xorn.config
  51
  52 ## Email address to which users should send bug reports.
  53 #
  54 # Set this to an appropriate value for your script.
  55
  56 bugreport = xorn.config.PACKAGE_BUGREPORT
  57
  58 ## Return the value of <tt>argv[0]</tt>.
  59 #
  60 # Python replaces <tt>sys.argv[0]</tt> with an absolute path if the
  61 # command was run from the search path.  This function tries to
  62 # compensate for this by returning just the basename if
  63 # <tt>sys.argv[0]</tt> is an absolute path.
  64
  65 def argv0():
  66     if sys.argv[0].startswith('/'):
  67         return os.path.basename(sys.argv[0])
  68     return sys.argv[0]
  69
  70 ## Name that was used to invoke the script.
  71 #
  72 # If the script was run by \c xorn, this is <tt>argv[0]</tt> plus a
  73 # space character plus the subcommand name.  Otherwise, it is the same
  74 # as <tt>argv[0]</tt>.
  75 #
  76 # Typically used in the output of \c \--help.
  77
  78 program_name = argv0()
  79
  80 ## Basename component of the name that was used to invoke the script.
  81 #
  82 # If the script was run by \c xorn, this is the basename of the
  83 # executed script, i.e., \c 'xorn-<i>something</i>'.  Otherwise, it is
  84 # the same as <tt>argv[0]</tt>, with all text up to and including the
  85 # final slash (/), if any, removed.
  86 #
  87 # Typically used in error messages.
  88
  89 program_short_name = os.path.basename(argv0())
  90
  91 ## List of command arguments.
  92 #
  93 # A list of unparsed arguments, starting with the first argument
  94 # following the invocation name.  If the script was run by \c xorn,
  95 # this is the right-hand part of \c argv with all \c xorn arguments
  96 # and the command name stripped.  Otherwise, it is the same as
  97 # <tt>argv[1:]</tt>.
  98
  99 args = sys.argv[1:]
 100
 101 ## Print an argument error message to \c sys.stdout and exit.
 102 #
 103 # This command prints an error message of the form
 104 # \verbatim
 105 # xorn-frobnicate: missing file operand
 106 # Try `xorn frobnicate --help' for more information.
 107 # \endverbatim
 108 # to \c sys.stderr and exits with status code \c 1.
 109
 110 def invalid_arguments(message):
 111     sys.stderr.write(_("%s: %s\n") % (program_short_name, message))
 112     sys.stderr.write(_("Try `%s --help' for more information.\n")
 113                      % program_name)
 114     sys.exit(1)
 115
 116 ## Print core version.
 117 #
 118 # Prints an output appropriate for the \c \--version option of the core
 119 # scripts to \c sys.stdout and exits with status code \c 0.
 120
 121 def core_version():
 122     sys.stdout.write("%s\n" % xorn.config.PACKAGE_STRING)
 123     sys.stdout.write(_("Copyright (C) 2020 Roland Lutz\n"))
 124     sys.stdout.write("\n")
 125     sys.stdout.write(_(
 126 "This program is free software; you can redistribute it and/or\n"
 127 "modify it under the terms of the GNU General Public License\n"
 128 "as published by the Free Software Foundation; either version 2\n"
 129 "of the License, or (at your option) any later version.\n"))
 130     sys.stdout.write("\n")
 131     sys.stdout.write(_(
 132 "This program is distributed in the hope that it will be useful,\n"
 133 "but WITHOUT ANY WARRANTY; without even the implied warranty of\n"
 134 "MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the\n"
 135 "GNU General Public License for more details.\n"))
 136     sys.exit(0)