Source code for xcp.environ

# Copyright (c) 2013, Citrix Inc.
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import os
import os.path

from .compat import open_with_codec_handling

EXTRA_SCRIPTS_DIR = '/mnt'



def installerRunning():
    return os.environ.get('XS_INSTALLATION', '0') != '0'




def buildingInitialTar():
    return 'CARBON_DISTROS_DIR' in os.environ




class InventoryError(Exception):
    pass




def readInventory(root = '/'):

    fh = None
    d = {}

    try:

        try:
            fh = open_with_codec_handling(os.path.join(root, "etc/xensource-inventory"))

            for line in (x for x in (y.strip() for y in fh)
                         if not x.startswith('#')):

                vals = line.split('=', 1)

                if ( len(vals) != 2 or
                     vals[0].endswith(" ") or vals[0].endswith("\t") or
                     vals[1].startswith(" ") or vals[1].startswith("\t") ):
                    raise InventoryError("Invalid line found '%s'" % (line,))

                d[vals[0]] = vals[1].strip('"\'')

        except IOError as e:
            raise InventoryError("Error reading from file '%s'" % (e,))

    finally:
        if fh:
            fh.close()

    return d