#!/usr/bin/python

import ConfigParser
import os
import sys

sys.stdout.write("builder running...\n")

# Initialization
os.system("mount -t tmpfs tmpfs /etc")
os.mkdir("/etc/rootstrap")
os.system("mount -t hostfs hostfs -o /etc/rootstrap /etc/rootstrap")
os.system("mount -t proc proc /proc")
os.system("mount -t tmpfs tmpfs /tmp")
os.mkdir("/tmp/target")
os.mkdir("/tmp/host")
os.system("mount -t hostfs hostfs /tmp/host")

# Parse kernel command line
workdir = '~/.rootstrap'
configfile = None
for arg in open('/proc/cmdline').read().split():
    argsplit = arg.split('=')
    if len(argsplit) > 1:
        if argsplit[0] == 'rsworkdir':
            workdir = os.path.expanduser(argsplit[1])
        elif argsplit[0] == 'rsconfig':
            configfile = '/tmp/host' + os.path.expanduser(os.path.join('/tmp/host',os.path.expanduser(argsplit[1])))

os.system("mount -t hostfs hostfs -o %s /etc/rootstrap/workdir" % workdir)

def dispatch(module, vars):
    "Invoke a rootstrap module"

    found = 0
    for scriptpat in ('/etc/rootstrap/workdir/modules/%s',
                      '/etc/rootstrap/modules/%s',
                      '/usr/lib/rootstrap/modules/%s'):
        script = scriptpat % module
        if os.path.exists(script):
            print "Using rootstrap module %s from:\n\t%s" % (module,script)
            status = os.spawnle(os.P_WAIT, script, script, vars)
            if status != 0:
                raise "rootstrap: Module '%s' failed, status: %d" % (module,status)
            return

    raise "rootstrap: unknown module: %s\n" % module
        
config = ConfigParser.ConfigParser()
config.optionxform = str # case sensitive
config.readfp(open('/etc/rootstrap/rootstrap.conf'))
config.read(('/etc/rootstrap/workdir/rootstrap.conf',))
if configfile:
    config.read(configfile)

globalvars = { 'TARGET' : '/tmp/target', 'WORKDIR' : '/etc/rootstrap/workdir' }
for var in config.options('global'):
    globalvars[var] = config.get('global', var)
    
for module in config.get('global', 'modules').split():
    modulevars = globalvars
    if config.has_section(module):
        for var in config.options(module):
            modulevars[var] = config.get(module,var)

    dispatch(module, modulevars)

os.system("mount -o remount,ro hostfs /")
os.system("/sbin/halt -d -f")
