Geografic-Information-System/lib/init/grass.py

#!/usr/bin/env python
#############################################################################
#
# MODULE:       GRASS initialization (Python)
# AUTHOR(S):    Original author unknown - probably CERL
#               Andreas Lange <andreas.lange rhein-main.de>
#               Huidae Cho <grass4u gmail.com>
#               Justin Hickey <jhickey hpcc.nectec.or.th>
#               Markus Neteler <neteler osgeo.org>
#               Hamish Bowman <hamish_b yahoo,com>
#               Converted to Python (based on init.sh) by Glynn Clements
#               Martin Landa <landa.martin gmail.com>
#               Luca Delucchi <lucadeluge@gmail.com>
# PURPOSE:      Sets up environment variables, parses any remaining 
#               command line options for setting the GISDBASE, LOCATION,
#               and/or MAPSET. Finally it starts GRASS with the appropriate user
#               interface and cleans up after it is finished.
# COPYRIGHT:    (C) 2000-2013 by the GRASS Development Team
#
#               This program is free software under the GNU General
#               Public License (>=v2). Read the file COPYING that
#               comes with GRASS for details.
#
#############################################################################

import sys
import os
import atexit
import string
import subprocess
import re
import platform
import tempfile

# Variables substituted during build process
if os.environ.has_key('GISBASE'):
    gisbase = os.environ['GISBASE']
else:
    gisbase = "@GISBASE@"
cmd_name = "@START_UP@"
grass_version = "@GRASS_VERSION_NUMBER@"
ld_library_path_var = '@LD_LIBRARY_PATH_VAR@'
if os.environ.has_key('GRASS_PROJSHARE'):
    config_projshare = os.environ['GRASS_PROJSHARE']
else:
    config_projshare = "@CONFIG_PROJSHARE@"

# configuration directory
grass_env_file = None # see check_shell()
if sys.platform == 'win32':
    grass_config_dirname = "GRASS7"
    grass_config_dir = os.path.join(os.getenv('APPDATA'), grass_config_dirname)
else:
    grass_config_dirname = ".grass7"
    grass_config_dir = os.path.join(os.getenv('HOME'), grass_config_dirname)

gisbase = os.path.normpath(gisbase)

# i18N
import gettext
gettext.install('grasslibs', os.path.join(gisbase, 'locale'), unicode = True)

tmpdir = None
lockfile = None
remove_lockfile = True
location = None
create_new = None
grass_gui = None

def warning(text):
    sys.stderr.write(_("WARNING") + ': ' + text + os.linesep)

def try_remove(path):
    try:
        os.remove(path)
    except:
        pass

def try_rmdir(path):
    try:
        os.rmdir(path)
    except:
        pass

def clean_env():
    env_curr = read_gisrc()
    env_new  = {}
    for k,v in env_curr.iteritems():
        if 'MONITOR' not in k:
            env_new[k] = v
    
    write_gisrc(env_new)

def cleanup_dir(path):
    if not path:
        return
    
    for root, dirs, files in os.walk(path, topdown = False):
        for name in files:
            try_remove(os.path.join(root, name))
        for name in dirs:
            try_rmdir(os.path.join(root, name))
    
def cleanup():
    tmpdir, lockfile, remove_lockfile
    # all exits after setting up tmp dirs (system/location) should
    # also tidy it up
    cleanup_dir(tmpdir)
    try_rmdir(tmpdir)
    if location:
        tmpdir_loc = os.path.join(location, ".tmp")
        cleanup_dir(tmpdir_loc)
        try_rmdir(tmpdir_loc)
    
    # remove lock-file if requested
    if lockfile and remove_lockfile:
        try_remove(lockfile)
    
def fatal(msg):
    sys.exit(msg)

def message(msg):
    sys.stderr.write(msg + "\n")
    sys.stderr.flush()

def readfile(path):
    f = open(path, 'r')
    s = f.read()
    f.close()
    return s

def writefile(path, s):
    f = open(path, 'w')
    f.write(s)
    f.close()

def call(cmd, **kwargs):
    if windows:
        kwargs['shell'] = True
    return subprocess.call(cmd, **kwargs)

def Popen(cmd, **kwargs):
    if windows:
        kwargs['shell'] = True
    return subprocess.Popen(cmd, **kwargs)

def gfile(*args):
    return os.path.join(gisbase, *args)

help_text = r"""GRASS GIS %s
Geographic Resources Analysis Support System (GRASS GIS).

%s:
  $CMD_NAME [-h | -help | --help] [-v | --version] [-c | -c geofile | -c EPSG:code]
          [-text | -gui] [--config param]
          [[[<GISDBASE>/]<LOCATION_NAME>/]<MAPSET>]

%s:
  -h or -help or --help          %s
  -v or --version                %s
  -c                             %s
  -text                          %s
                                   %s
  -gui                           %s
                                   %s
  --config                       %s
                                   %s

%s:
  GISDBASE                       %s
  LOCATION_NAME                  %s
  MAPSET                         %s

  GISDBASE/LOCATION_NAME/MAPSET  %s

%s:
  GRASS_GUI                      %s
  GRASS_WISH                     %s
  GRASS_HTML_BROWSER             %s
  GRASS_ADDON_PATH               %s
  GRASS_ADDON_BASE               %s
  GRASS_BATCH_JOB                %s
  GRASS_PYTHON                   %s
""" % (grass_version,
       _("Usage"),
       _("Flags"),
       _("print this help message"),
       _("show version information and exit"),
       _("create given database, location or mapset if it doesn't exist"),
       _("use text based interface"),
       _("and set as default"),
       _("use $DEFAULT_GUI graphical user interface"),
       _("and set as default"),
       _("print GRASS configuration parameters"),
       _("options: arch,build,compiler,path,revision"),
       _("Parameters"),
       _("initial database (path to GIS data)"),
       _("initial location"),
       _("initial mapset"),
       _("fully qualified initial mapset directory"),
       _("Environment variables relevant for startup"),
       _("select GUI (text, gui)"),
       _("set wish shell name to override 'wish'"),
       _("set html web browser for help pages"),
       _("set additional path(s) to local GRASS modules or user scripts"),
       _("set additional GISBASE for locally installed GRASS Addons"),
       _("shell script to be processed as batch job"),
       _("set python shell name to override 'python'"))


def help_message():
    t = string.Template(help_text)
    s = t.substitute(CMD_NAME = cmd_name, DEFAULT_GUI = default_gui)
    sys.stderr.write(s)

def create_tmp():
    global tmpdir
    ## use $TMPDIR if it exists, then $TEMP, otherwise /tmp
    tmp = os.getenv('TMPDIR')
    if not tmp:
        tmp = os.getenv('TEMP')
    if not tmp:
        tmp = tempfile.gettempdir()
    if not tmp:
        tmp = '/tmp'
    tmpdir = os.path.join(tmp, "grass7-%s-%s" % (user, gis_lock))
    try:
        os.mkdir(tmpdir, 0700)
    except:
        fatal(_("Unable to create temporary directory <%s>! Exiting.") % tmpdir)

def create_gisrc():
    global gisrc, gisrcrc
    # Set the session grassrc file
    gisrc = os.path.join(tmpdir, "gisrc")
    os.environ['GISRC'] = gisrc
    
    # remove invalid GISRC file to avoid disturbing error messages:
    try:
        s = readfile(gisrcrc)
        if "UNKNOWN" in s:
            try_remove(gisrcrc)
            s = None
    except:
        s = None
    
    # Copy the global grassrc file to the session grassrc file
    if s:
        writefile(gisrc, s)
    
def read_gisrc():
    kv = {}
    try:
        f = open(gisrc, 'r')
    except IOError:
        return kv
    
    for line in f:
        k, v = line.split(':', 1)
        kv[k.strip()] = v.strip()
    f.close()
    
    return kv

def read_env_file(path):
    kv = {}
    f = open(path, 'r')
    for line in f:
        k, v = line.split(':', 1)
        kv[k.strip()] = v.strip()
    f.close()
    return kv

def write_gisrc(kv):
    f = open(gisrc, 'w')
    for k, v in kv.iteritems():
        f.write("%s: %s\n" % (k, v))
    f.close()

def read_gui():
    global grass_gui
    # At this point the GRASS user interface variable has been set from the
    # command line, been set from an external environment variable, or is 
    # not set. So we check if it is not set
    if not grass_gui:
        # Check for a reference to the GRASS user interface in the grassrc file
        if os.access(gisrc, os.R_OK):
            kv = read_gisrc()
            if 'GRASS_GUI' in os.environ:
                grass_gui = os.environ['GRASS_GUI']
            elif 'GUI' in kv:
                grass_gui = kv['GUI']
            elif 'GRASS_GUI' in kv:
                # For backward compatibility (GRASS_GUI renamed to GUI)
                grass_gui = kv['GRASS_GUI']
            else:
                # Set the GRASS user interface to the default if needed
                grass_gui = default_gui
    
    if not grass_gui:
        grass_gui = default_gui
    
    if grass_gui == 'gui':
        grass_gui = default_gui
    
    # FIXME oldtcltk, gis.m, d.m no longer exist
    if grass_gui in ['d.m', 'gis.m', 'oldtcltk', 'tcltk']:
        warning(_("GUI <%s> not supported in this version") % grass_gui)
        grass_gui = default_gui
    
def path_prepend(dir, var):
    path = os.getenv(var)
    if path:
        path = dir + os.pathsep + path
    else:
        path = dir
    os.environ[var] = path

def path_append(dir, var):
    path = os.getenv(var)
    if path:
        path = path + os.pathsep + dir
    else:
        path = dir
    os.environ[var] = path

def set_paths():
    # addons (path)
    addon_path = os.getenv('GRASS_ADDON_PATH')
    if addon_path:
        for path in addon_path.split(os.pathsep):
            path_prepend(addon_path, 'PATH')
    
    # addons (base)
    addon_base = os.getenv('GRASS_ADDON_BASE')
    if not addon_base:
        addon_base = os.path.join(grass_config_dir, 'addons')
        os.environ['GRASS_ADDON_BASE'] = addon_base
    path_prepend(os.path.join(addon_base, 'scripts'), 'PATH')
    path_prepend(os.path.join(addon_base, 'bin'), 'PATH')
    
    # standard installation
    path_prepend(gfile('scripts'), 'PATH')
    path_prepend(gfile('bin'), 'PATH')
    
    # Set PYTHONPATH to find GRASS Python modules
    path_prepend(gfile('etc', 'python'), 'PYTHONPATH')
    
    # set path for the GRASS man pages
    grass_man_path = os.path.join(gisbase, 'docs', 'man')
    addons_man_path = os.path.join(addon_base, 'docs', 'man')
    man_path = os.getenv('MANPATH')
    if man_path:
        path_prepend(addons_man_path, 'MANPATH')
        path_prepend(grass_man_path, 'MANPATH')
    else:
        try:
            nul = open(os.devnull, 'w')
            p = Popen(['manpath'], stdout = subprocess.PIPE, stderr = nul)
            nul.close()
            s = p.stdout.read()
            p.wait()
            sys_man_path = s.strip()
        except:
            pass
        
        if sys_man_path:
            os.environ['MANPATH'] = sys_man_path
            path_prepend(addons_man_path, 'MANPATH')
            path_prepend(grass_man_path, 'MANPATH')
        else:
            os.environ['MANPATH'] = addons_man_path
            path_prepend(grass_man_path, 'MANPATH')
    
    # Add .py (Python) to list of executable extensions to search for
    # in MS-Windows PATH
    if windows:
        path_append('.PY', 'PATHEXT')
    
def find_exe(pgm):
    for dir in os.getenv('PATH').split(os.pathsep):
        path = os.path.join(dir, pgm)
        if os.access(path, os.X_OK):
            return path
    return None

def set_defaults():
    # GRASS_PAGER
    if not os.getenv('GRASS_PAGER'):
        if find_exe("more"):
            pager = "more"
        elif find_exe("less"):
            pager = "less"
        elif windows:
            pager = "more"
        else:
            pager = "cat"
        os.environ['GRASS_PAGER'] = pager
    
    # GRASS_WISH
    if not os.getenv('GRASS_WISH'):
        os.environ['GRASS_WISH'] = "wish"
    
    # GRASS_PYTHON
    if not os.getenv('GRASS_PYTHON'):
        if windows:
            os.environ['GRASS_PYTHON'] = "python.exe"
        else:
            os.environ['GRASS_PYTHON'] = "python"
    
    # GRASS_GNUPLOT
    if not os.getenv('GRASS_GNUPLOT'):
        os.environ['GRASS_GNUPLOT'] = "gnuplot -persist"
    
    # GRASS_PROJSHARE
    if not os.getenv('GRASS_PROJSHARE'):
        os.environ['GRASS_PROJSHARE'] = config_projshare
        
def set_browser():
    # GRASS_HTML_BROWSER
    browser = os.getenv('GRASS_HTML_BROWSER')
    if not browser:
        if macosx:
            # OSX doesn't execute browsers from the shell PATH - route thru a script
            browser = gfile('etc', "html_browser_mac.sh")
            os.environ['GRASS_HTML_BROWSER_MACOSX'] = "-b com.apple.helpviewer"
        
        if windows or cygwin:
            # MinGW startup moved to into init.bat
            browser = "explorer"
        else:
            # the usual suspects
            browsers = [ "xdg-open", "htmlview", "konqueror", "mozilla", "mozilla-firefox",
                         "firefox", "iceweasel", "opera", "netscape", "dillo", "lynx", "links", "w3c" ]
            for b in browsers:
                if find_exe(b):
                    browser = b
                    break
    
    elif macosx:
        # OSX doesn't execute browsers from the shell PATH - route thru a script
        os.environ['GRASS_HTML_BROWSER_MACOSX'] = "-b %s" % browser
        browser = gfile('etc', "html_browser_mac.sh")
    
    if not browser:
        warning(_("Searched for a web browser, but none found"))
        # even so we set konqueror to make lib/gis/parser.c happy:
        browser = "konqueror"
    
    os.environ['GRASS_HTML_BROWSER'] = browser

def grass_intro():
    intro = r"""
WELCOME TO GRASS %s

   1) Have at your side all available GRASS tutorials

   2) When working on your location, the following materials
      are extremely useful:
      - A topo map of your area
      - Current catalog of available computer maps

   3) Check the GRASS webpages for feedback mailinglists and more:
      http://grass.osgeo.org
      http://www.grass-gis.org
""" % grass_version
    sys.stderr.write(intro)
    
    sys.stderr.write("\n")
    sys.stderr.write(_("Hit RETURN to continue"))
    sys.stdin.readline()
    
    # for convenience, define pwd as GISDBASE:
    s = r"""GISDBASE: %s
LOCATION_NAME: <UNKNOWN>
MAPSET: <UNKNOWN>
""" % os.getcwd()
    writefile(gisrc, s)

def check_gui():
    global grass_gui, wxpython_base
    # Check if we are running X windows by checking the DISPLAY variable
    if os.getenv('DISPLAY') or windows:
        # Check if python is working properly
        if grass_gui == 'wxpython':
            nul = open(os.devnull, 'w')
            p = Popen([os.environ['GRASS_PYTHON']],
                      stdin = subprocess.PIPE,
                      stdout = nul, stderr = nul)
            nul.close()
            p.stdin.write("variable=True")
            p.stdin.close()
            p.wait()
            if p.returncode == 0:
                # Set the wxpython base directory
                wxpython_base = gfile("etc", "gui", "wxpython")
            else:
                # Python was not found - switch to text interface mode
                warning(_("The python command does not work as expected!\n"
                          "Please check your GRASS_PYTHON environment variable.\n"
                          "Use the -help option for details.\n"
                          "Switching to text based interface mode.\n\n"
                          "Hit RETURN to continue.\n"))
                sys.stdin.readline()
                grass_gui = 'text'
    
    else:
        # Display a message if a graphical interface was expected
        if grass_gui != 'text':
            # Set the interface mode to text
            warning(_("It appears that the X Windows system is not active.\n"
                      "A graphical based user interface is not supported.\n"
                      "Switching to text based interface mode.\n\n"
                      "Hit RETURN to continue"""))
            sys.stdin.readline()
            grass_gui = 'text'
    
    # Save the user interface variable in the grassrc file - choose a temporary
    # file name that should not match another file
    if os.access(gisrc, os.F_OK):
        kv = read_gisrc()
        kv['GUI'] = grass_gui
        write_gisrc(kv)

def non_interactive(arg, geofile = None):
    global gisdbase, location_name, mapset, location
    # Try non-interactive startup
    l = None
    
    if arg == '-':
        if location:
            l = location
    else:
        l = arg
    
    if l:
        if l == '.':
            l = os.getcwd()
        elif not os.path.isabs(l):
            l = os.path.abspath(l)
        
        l, mapset = os.path.split(l)
        if not mapset:
            l, mapset = os.path.split(l)
        l, location_name = os.path.split(l)
        gisdbase = l
    
    if gisdbase and location_name and mapset:
        location = os.path.join(gisdbase, location_name, mapset)
        
        if not os.access(os.path.join(location, "WIND"), os.R_OK):
            if location_name == "PERMANENT":
                fatal(_("<%s> is not a valid GRASS location") % location)
            else:
                # the user wants to create mapset on the fly
                if create_new:
                    if not os.access(os.path.join(os.path.join(gisdbase, location_name,
                                                               "PERMANENT", "DEFAULT_WIND")), os.F_OK):
                        # create new location
                        gisdbase = os.path.join(gisdbase, location_name)
                        location_name = mapset
                        mapset = "PERMANENT"
                        if os.access(os.path.join(os.path.join(gisdbase, location_name,
                                                               "PERMANENT", "DEFAULT_WIND")), os.F_OK):
                            fatal(_("Failed to create new location. The location <%s> already exists." % location_name))
                        sys.path.append(gfile('etc', 'python'))
                        from grass.script import core as grass
                        try:
                            if geofile and geofile.find('EPSG:') > -1:
                                epsg = geofile.split(':', 1)[1]
                                grass.create_location(gisdbase, location_name, epsg = epsg)
                            else:
                                grass.create_location(gisdbase, location_name, filename = geofile)
                        except grass.ScriptError, e:
                            fatal(e.value.strip('"').strip("'").replace('\\n', os.linesep))
                    else:
                        # create new mapset
                        os.mkdir(location)
                        # copy PERMANENT/DEFAULT_WIND to <mapset>/WIND
                        s = readfile(os.path.join(gisdbase, location_name, "PERMANENT", "DEFAULT_WIND"))
                        writefile(os.path.join(location, "WIND"), s)
                        message(_("Missing WIND file fixed"))
                else:
                    fatal(_("<%s> is not a valid GRASS location") % location)
        
        if os.access(gisrc, os.R_OK):
            kv = read_gisrc()
        else:
            kv = {}
        
        kv['GISDBASE'] = gisdbase
        kv['LOCATION_NAME'] = location_name
        kv['MAPSET'] = mapset
        write_gisrc(kv)
    else:
        fatal(_("GISDBASE, LOCATION_NAME and MAPSET variables not set properly.\n"
                "Interactive startup needed."))
    
def set_data():
    # User selects LOCATION and MAPSET if not set
    if not location:
        # Check for text interface
        if grass_gui == 'text':
            pass
        # Check for GUI
        elif grass_gui == 'wxpython':
            gui_startup()
        else:
            # Shouldn't need this but you never know
            fatal(_("Invalid user interface specified - <%s>.\n" 
                    "Use the --help option to see valid interface names.") % grass_gui)
    
def gui_startup():
    if grass_gui == 'wxpython':
        thetest = call([os.getenv('GRASS_PYTHON'),
                        gfile(wxpython_base, "gis_set.py")])
    
    if thetest == 0:
        pass
    elif thetest == 1:
        # The startup script printed an error message so wait
        # for user to read it
        message(_("Error in GUI startup. If necessary, please "
                  "report this error to the GRASS developers.\n"
                  "Switching to text mode now.\n\n"
                  "Hit RETURN to continue..."))
        sys.stdin.readline()
        
        os.execlp(cmd_name, "-text")
        sys.exit(1)
    elif thetest == 2:
        # User wants to exit from GRASS
        message(_("Received EXIT message from GUI.\nGRASS is not started. Bye."))
        sys.exit(0)
    else:
        fatal(_("Invalid return code from GUI startup script.\n"
                "Please advise GRASS developers of this error."))
    
def load_gisrc():
    global gisdbase, location_name, mapset, location
    kv = read_gisrc()
    gisdbase = kv.get('GISDBASE')
    location_name = kv.get('LOCATION_NAME')
    mapset = kv.get('MAPSET')
    if not gisdbase or not location_name or not mapset:
        fatal(_("Error reading data path information from g.gisenv.\n"
                "GISDBASE=%(gisbase)s\n"
                "LOCATION_NAME=%(location)s\n"
                "MAPSET=%(mapset)s\n\n"
                "Check the <%s(file)> file." % \
                    { 'gisbase' : gisdbase, 'location' : location_name,
                      'mapset' : mapset, 'file' : gisrcrc }))
    
    location = os.path.join(gisdbase, location_name, mapset)

# load environmental variables from grass_env_file
def load_env():
    if not os.access(grass_env_file, os.R_OK):
        return
    
    for line in readfile(grass_env_file).split(os.linesep):
        try:
            k, v = map(lambda x: x.strip(), line.strip().split(' ', 1)[1].split('=', 1))
        except:
            continue
        os.environ[k] = v
    
def set_language():
    import locale
    
    language = os.getenv('LANG')
    if not language:
        return
    
    language = language.split('.')[0] # Split off ignored .encoding part if present
    orig_language = language
    try:
        locale.setlocale(locale.LC_ALL, language)
    except locale.Error, e:
        if sys.platform != 'win32': # Don't try on Windows, it will probably not work
            # sys.stderr.write("Failed to set LC_ALL to %s (%s)\n" % (language, e))
            try:
                # Locale lang.encoding might be missing. Let's try
                # UTF-8 encoding before giving up as on Linux systems
                # lang.UTF-8 locales are more common than legacy
                # ISO-8859 ones.
                language = locale.normalize('%s.UTF-8' % (language))
                locale.setlocale(locale.LC_ALL, language)
            except locale.Error, e:
                # If we got so far, provided locale is not supported
                # on this system
                sys.stderr.write("Failed to set LC_ALL to %s (%s)\n" % (language, e))
                ### locale.getdefaultlocale() is probably related to gettext?
                # try:
                #     default_locale = locale.getdefaultlocale()
                # except:
                #     default_locale = None
                # if default_locale and default_locale[0]:
                #     language = default_locale[0]
                # else:
                language = 'C'
    
    # Set up environment for subprocesses
    for lc in ('LC_CTYPE', 'LC_MESSAGES', 'LC_TIME', 'LC_COLLATE', 'LC_MONETARY', 'LC_PAPER',
               'LC_NAME', 'LC_ADDRESS', 'LC_TELEPHONE', 'LC_MEASUREMENT', 'LC_IDENTIFICATION'):
        os.environ[lc] = language
            
    # Some code in GRASS might not like other decimal separators than .
    # Other potential sources for problems are: LC_TIME LC_CTYPE
    locale.setlocale(locale.LC_NUMERIC, 'C')
    os.environ['LC_NUMERIC'] = 'C'
    if os.getenv('LC_ALL'):
        del os.environ['LC_ALL'] # Remove LC_ALL to not override LC_NUMERIC
    
    # Even if setting locale has failed, let's set LANG in a hope,
    # that UI will use it GRASS texts will be in selected language,
    # system messages (i.e. OK, Cancel etc.) - in system default
    # language
    os.environ['LANGUAGE'] = orig_language
    os.environ['LANG'] = orig_language
        
    # Calling gettext.install twice seems to allow to see also
    # localized startup messages Black magic ;)
    gettext.install('grasslibs', os.path.join(gisbase, 'locale'), unicode = True)
    
def check_lock():
    global lockfile
    if not os.path.exists(location):
        fatal(_("Path '%s' doesn't exist") % location)
    
    # Check for concurrent use
    lockfile = os.path.join(location, ".gislock")
    ret = call([gfile("etc", "lock"),
                lockfile,
                "%d" % os.getpid()])
    
    if ret == 0:
        msg = None
    elif ret == 2:
        msg = _("%(user)s is currently running GRASS in selected mapset (file %(file)s found). "
                "Concurrent use not allowed." % \
                    { 'user' : user, 'file' : lockfile })
    else:
        msg = _("Unable to properly access '%s'.\n"
                "Please notify system personel.") % lockfile
    
    if msg:
        if grass_gui == "wxpython":
            thetest = call([os.getenv('GRASS_PYTHON'), os.path.join(wxpython_base, "gis_set_error.py"), msg])
        else:
            global remove_lockfile
            remove_lockfile = False
            fatal(msg)
    
def make_fontcap():
    fc = os.getenv('GRASS_FONT_CAP')
    if fc and not os.access(fc, os.R_OK):
        message(_("Building user fontcap..."))
        call(["g.mkfontcap"])
    
def check_shell():
    global sh, shellname, grass_env_file
    # cygwin has many problems with the shell setup
    # below, so i hardcoded everything here.
    if os.getenv('CYGWIN'):
        sh = "cygwin"
        shellname = "GNU Bash (Cygwin)"
        os.environ['SHELL'] = "/usr/bin/bash.exe"
        os.environ['OSTYPE'] = "cygwin"
    else:
        sh = os.path.basename(os.getenv('SHELL'))
        if windows and sh:
            sh = os.path.splitext(sh)[0]
        
        if sh == "ksh":
            shellname = "Korn Shell"
        elif sh == "csh":
            shellname = "C Shell" 
        elif sh == "tcsh":
            shellname = "TC Shell" 
        elif sh == "bash":
            shellname = "Bash Shell" 
        elif sh == "sh":
            shellname = "Bourne Shell"
        elif sh == "zsh":
            shellname = "Z Shell"
        elif sh == "cmd":
            shellname = "Command Shell"
        else:
            shellname = "shell"
    
    if sh in ['csh', 'tcsh']:
        grass_env_file = os.path.join(grass_config_dir, 'cshrc')
    elif sh in ['bash', 'msh', 'cygwin', 'sh']:
        grass_env_file = os.path.join(grass_config_dir, 'bashrc')
    elif sh == 'zsh':
        grass_env_file = os.path.join(grass_config_dir, 'zshrc')
    elif sh == 'cmd':
        grass_env_file = os.path.join(grass_config_dir, 'env.bat')
    else:
        grass_env_file = os.path.join(grass_config_dir, 'bashrc')
        warning(_("Unsupported shell <%s>: %s") % (sh, grass_env_file))
    
    # check for SHELL
    if not os.getenv('SHELL'):
        fatal(_("The SHELL variable is not set"))
    
def check_batch_job():
    global batch_job
    # hack to process batch jobs:
    batch_job = os.getenv('GRASS_BATCH_JOB')
    if batch_job:
        # defined, but ...
        if not os.access(batch_job, os.F_OK):
          # wrong file
          fatal(_("Job file '%s' has been defined in "
                  "the 'GRASS_BATCH_JOB' variable but not found. Exiting.\n\n"
                  "Use 'unset GRASS_BATCH_JOB' to disable batch job processing.") % batch_job)
        elif not os.access(batch_job, os.X_OK):
            # right file, but ...
            fatal(_("Change file permission to 'executable' for '%s'") % batch_job)
        else:
            message(_("Executing '%s' ...") % batch_job)
            grass_gui = "text"
            shell = batch_job
            bj = Popen(shell, shell=True)
            bj.wait()
            message(_("Execution of '%s' finished.") % batch_job)
    
def start_gui():
    # Start the chosen GUI but ignore text
    if grass_debug:
        message(_("GRASS GUI should be <%s>") % grass_gui)
    
    # Check for gui interface
    if grass_gui == "wxpython":
        Popen([os.getenv('GRASS_PYTHON'),
               gfile(wxpython_base, "wxgui.py")])
    
def clear_screen():
    if windows:
        pass
    # TODO: uncomment when PDCurses works.
    #   cls
    else:
        if not os.getenv('GRASS_BATCH_JOB') and not grass_debug:
            call(["tput", "clear"])
    
def show_banner():
    sys.stderr.write(r"""
          __________  ___   __________    _______________
         / ____/ __ \/   | / ___/ ___/   / ____/  _/ ___/
        / / __/ /_/ / /| | \__ \\_  \   / / __ / / \__ \ 
       / /_/ / _, _/ ___ |___/ /__/ /  / /_/ // / ___/ / 
       \____/_/ |_/_/  |_/____/____/   \____/___//____/  

""")


def say_hello():
    sys.stderr.write(_("Welcome to GRASS %s") % grass_version)

def show_info():
    sys.stderr.write(
r"""
%-41shttp://grass.osgeo.org
%-41s%s (%s)
%-41sg.manual -i
%-41sg.version -c
""" % (_("GRASS homepage:"),
       _("This version running through:"),
       shellname, os.getenv('SHELL'),
       _("Help is available with the command:"),
       _("See the licence terms with:")))
    
    if grass_gui == 'wxpython':
        message("%-41sg.gui wxpython" % _("If required, restart the GUI with:"))
    else:
        message("%-41sg.gui %s" % (_("Start the GUI with:"), default_gui))
    
    message("%-41sexit" % _("When ready to quit enter:"))
    message("")

def csh_startup():
    global exit_val
    
    userhome = os.getenv('HOME')      # save original home
    home = location
    os.environ['HOME'] = home
    
    cshrc = os.path.join(home, ".cshrc")
    tcshrc = os.path.join(home, ".tcshrc")
    try_remove(cshrc)
    try_remove(tcshrc)
    
    f = open(cshrc, 'w')
    f.write("set home = %s\n" % userhome)
    f.write("set history = 3000 savehist = 3000  noclobber ignoreeof\n")
    f.write("set histfile = %s\n" % os.path.join(os.getenv('HOME'), ".history"))
    
    f.write("set prompt = '\\\n")
    f.write("Mapset <%s> in Location <%s> \\\n" % (mapset, location_name))
    f.write("GRASS %s > '\n" % grass_version)
    f.write("set BOGUS=``;unset BOGUS\n")
    
    path = os.path.join(userhome, ".grass.cshrc") # left for backward compatibility
    if os.access(path, os.R_OK):
        f.write(readfile(path) + '\n')
    if os.access(grass_env_file, os.R_OK):
        f.write(readfile(grass_env_file) + '\n')
    
    mail_re = re.compile(r"^ *set  *mail *= *")
    
    for filename in [".cshrc", ".tcshrc", ".login"]:
        path = os.path.join(userhome, filename)
        if os.access(path, os.R_OK):
            s = readfile(path)
            lines = s.splitlines()
            for l in lines:
                if mail_re.match(l):
                    f.write(l)
    
    path = os.getenv('PATH').split(':')
    f.write("set path = ( %s ) \n" % ' '.join(path))
    
    f.close()
    writefile(tcshrc, readfile(cshrc))
    
    exit_val = call([gfile("etc", "run"), os.getenv('SHELL')])
    
    os.environ['HOME'] = userhome
    
def bash_startup():
    global exit_val
    
    # save command history in mapset dir and remember more
    os.environ['HISTFILE'] = os.path.join(location, ".bash_history")
    if not os.getenv('HISTSIZE') and not os.getenv('HISTFILESIZE'):
        os.environ['HISTSIZE'] = "3000"
    
    # instead of changing $HOME, start bash with: --rcfile "$LOCATION/.bashrc" ?
    #   if so, must care be taken to explicity call .grass.bashrc et al for
    #   non-interactive bash batch jobs?
    userhome = os.getenv('HOME')      # save original home
    home = location                   # save .bashrc in $LOCATION
    os.environ['HOME'] = home
    
    bashrc = os.path.join(home, ".bashrc")
    try_remove(bashrc)
    
    f = open(bashrc, 'w')
    f.write("test -r ~/.alias && . ~/.alias\n")
    f.write("PS1='GRASS %s (%s):\w > '\n" % (grass_version, location_name))
    f.write("PROMPT_COMMAND=\"'%s'\"\n" % os.path.join(gisbase, 'etc', 'prompt.py'))
    
    # read environmental variables
    path = os.path.join(userhome, ".grass.bashrc") # left for backward compatibility
    if os.access(path, os.R_OK):
        f.write(readfile(path) + '\n')
    if os.access(grass_env_file, os.R_OK):
        f.write(readfile(grass_env_file) + '\n')
    
    f.write("export PATH=\"%s\"\n" % os.getenv('PATH'))
    f.write("export HOME=\"%s\"\n" % userhome) # restore user home path
    
    f.close()

    exit_val = call([gfile("etc", "run"), os.getenv('SHELL')])
    
    os.environ['HOME'] = userhome

def default_startup():
    global exit_val
    
    if windows:
        os.environ['PS1'] = "GRASS %s> " % (grass_version)
        # "$ETC/run" doesn't work at all???
        exit_val = subprocess.call([os.getenv('SHELL')])
        cleanup_dir(os.path.join(location, ".tmp"))  # remove GUI session files from .tmp
    else:
        os.environ['PS1'] = "GRASS %s (%s):\w > " % (grass_version, location_name)
        exit_val = call([gfile("etc", "run"), os.getenv('SHELL')])
    
    if exit_val != 0:
        fatal(_("Failed to start shell '%s'") % os.getenv('SHELL'))
    
def done_message():
    if batch_job and os.access(batch_job, os.X_OK):
        message(_("Batch job '%s' (defined in GRASS_BATCH_JOB variable) was executed.") % batch_job)
        message(_("Goodbye from GRASS GIS"))
        sys.exit(exit_val)
    else:
        message(_("Done."))
        message("")
        message(_("Goodbye from GRASS GIS"))
        message("")
    
def clean_temp():
    message(_("Cleaning up temporary files..."))
    nul = open(os.devnull, 'w')
    call([gfile("etc", "clean_temp")], stdout = nul, stderr = nul)
    nul.close()

def grep(string,list):
    expr = re.compile(string)
    return [elem for elem in list if expr.match(elem)]

def print_params():
    plat = gfile(gisbase, 'include', 'Make', 'Platform.make')
    fileplat = open(plat)
    linesplat = fileplat.readlines()
    fileplat.close()
    
    params = sys.argv[2:]
    if not params:
        params = ['arch', 'build', 'compiler', 'path', 'revision']
        
    for arg in params:
        if arg == 'path':
            sys.stdout.write("%s\n" % gisbase)
        elif arg == 'arch':
            val = grep('ARCH',linesplat)
            sys.stdout.write("%s\n" % val[0].split('=')[1].strip())
        elif arg == 'build':
            build = os.path.join(gisbase,'include','grass','confparms.h')
            filebuild = open(build)
            val = filebuild.readline()
            filebuild.close()
            sys.stdout.write("%s\n" % val.strip().strip('"').strip())
        elif arg == 'compiler':
            val = grep('CC',linesplat)
            sys.stdout.write("%s\n" % val[0].split('=')[1].strip())
        elif arg == 'revision':
            rev = os.path.join(gisbase,'include','grass','gis.h')
            filerev = open(rev)
            linesrev = filerev.readlines()
            val = grep('#define GIS_H_VERSION', linesrev)
            filerev.close()
            sys.stdout.write("%s\n" % val[0].split(':')[1].rstrip('$"\n').strip())
        else:
            message(_("Parameter <%s> not supported") % arg)
    
def get_username():
    global user
    if windows:
        user = os.getenv('USERNAME')
        if not user:
            user = "user_name"
    else:
        user = os.getenv('USER')
        if not user:
            user = os.getenv('LOGNAME')
        if not user:
            try:
                p = Popen(['whoami'], stdout = subprocess.PIPE)
                s = p.stdout.read()
                p.wait()
                user = s.strip()
            except:
                pass
        if not user:
            user = "user_%d" % os.getuid()
    
def parse_cmdline():
    global args, grass_gui, create_new
    args = []
    for i in sys.argv[1:]:
        # Check if the user asked for the version
        if i in ["-v", "--version"]:
            message('\n' + readfile(gfile("etc", "license")))
            sys.exit()
        # Check if the user asked for help
        elif i in ["help", "-h", "-help", "--help"]:
            help_message()
            sys.exit()
        # Check if the -text flag was given
        elif i in ["-text", "--text"]:
            grass_gui = 'text'
        # Check if the -gui flag was given
        elif i in ["-gui", "--gui"]:
            grass_gui = default_gui
        # Check if the -wxpython flag was given
        elif i in ["-wxpython", "-wx", "--wxpython", "--wx"]:
            grass_gui = 'wxpython'
        # Check if the user wants to create a new mapset
        elif i == "-c":
            create_new = True
        elif i == "--config":
            print_params()
            sys.exit()
        else:
            args.append(i)

### MAIN script starts here

# Get the system name
windows = sys.platform == 'win32'
cygwin = "cygwin" in sys.platform
macosx = "darwin" in sys.platform

# Set GISBASE
os.environ['GISBASE'] = gisbase

# set HOME
if windows and not os.getenv('HOME'):
    os.environ['HOME'] = os.path.join(os.getenv('HOMEDRIVE'), os.getenv('HOMEPATH'))

# set SHELL
if windows:
    if os.getenv('GRASS_SH'):
        os.environ['SHELL'] = os.getenv('GRASS_SH')
    if not os.getenv('SHELL'):
        os.environ['SHELL'] = os.getenv('COMSPEC', 'cmd.exe')

atexit.register(cleanup)

# Set default GUI
default_gui = "wxpython"

# the following is only meant to be an internal variable for debugging this script.
#  use 'g.gisenv set="DEBUG=[0-5]"' to turn GRASS debug mode on properly.
grass_debug = os.getenv('GRASS_DEBUG')

# Set GRASS version number for R interface etc (must be an env_var for MS-Windows)
os.environ['GRASS_VERSION'] = grass_version

# Set the GIS_LOCK variable to current process id
gis_lock = str(os.getpid())
os.environ['GIS_LOCK'] = gis_lock

# Set the global grassrc file
batch_job = os.getenv('GRASS_BATCH_JOB')
if batch_job:
    gisrcrc = os.path.join(grass_config_dir, "rc.%s" % platform.node())
    if not os.access(gisrcrc, os.R_OK):
        gisrcrc = os.path.join(grass_config_dir, "rc")
else:
    gisrcrc = os.path.join(grass_config_dir, "rc")

# Set the username and working directory
get_username()

# Parse the command-line options
parse_cmdline()

# Create the temporary directory and session grassrc file
create_tmp()

# Create the session grassrc file
create_gisrc()

# Set shell (needs to be called before load_env())
check_shell()

# Load environmental variables from the file
load_env()

# Ensure GUI is set
read_gui()

# Set PATH, PYTHONPATH
set_paths()

# Set LD_LIBRARY_PATH (etc) to find GRASS shared libraries
path_prepend(gfile("lib"), ld_library_path_var)

# Set GRASS_PAGER, GRASS_WISH, GRASS_PYTHON, GRASS_GNUPLOT, GRASS_PROJSHARE
set_defaults()

# Set GRASS_HTML_BROWSER
set_browser()

#predefine monitor size for certain architectures
if os.getenv('HOSTTYPE') == 'arm':
    # small monitor on ARM (iPAQ, zaurus... etc)
    os.environ['GRASS_HEIGHT'] = "320"
    os.environ['GRASS_WIDTH']  = "240"

# First time user - GISRC is defined in the GRASS script
if not os.access(gisrc, os.F_OK):
    if grass_gui == 'text' and len(args) == 0:
        fatal(_("Unable to start GRASS. You can:\n"
                " - Launch GRASS with '-gui' switch (`grass70 -gui`)\n"
                " - Create manually GISRC file (%s)\n"
                " - Launch GRASS with path to "
                "the location/mapset as an argument (`grass70 /path/to/location/mapset`)") % gisrcrc)
    grass_intro()
else:
    clean_temp()

message(_("Starting GRASS GIS..."))

# Check that the GUI works
check_gui()

# Parsing argument to get LOCATION
if not args:
    # Try interactive startup
    location = None
else:
    if create_new:
        if len(args) > 1:
            non_interactive(args[1], args[0])
        else:
            non_interactive(args[0])
    else:
        non_interactive(args[0])

# Set language
set_language()

# User selects LOCATION and MAPSET if not set
set_data()

# Set GISDBASE, LOCATION_NAME, MAPSET, LOCATION from $GISRC
load_gisrc()

# Check .gislock file
check_lock()

# build user fontcap if specified but not present
make_fontcap()

# predefine default driver if DB connection not defined
#  is this really needed?? Modules should call this when/if required.
if not os.access(os.path.join(location, "VAR"), os.F_OK):
    call(['db.connect', '-c', '--quiet'])

check_batch_job()

if not batch_job:       
    start_gui()

clear_screen()

# Display the version and license info
if batch_job:
    say_hello()
    grass_gui = 'text'
    clear_screen()
    clean_temp()
    try_remove(lockfile)
    sys.exit(0)
else:
    show_banner()
    say_hello()
    show_info()
    if grass_gui == "wxpython":
        message(_("Launching <%s> GUI in the background, please wait...") % grass_gui)

if sh in ['csh', 'tcsh']:
    csh_startup()
elif sh in ['bash', 'msh', 'cygwin']:
    bash_startup()
else:
    default_startup()

clear_screen()

clean_env()
clean_temp()

try_remove(lockfile)

# Save GISRC
s = readfile(gisrc)
if not os.path.exists(grass_config_dir):
    os.mkdir(grass_config_dir)
writefile(gisrcrc, s)

cleanup()

# After this point no more grass modules may be called

done_message()