+
−import os, sys
+
−from ctypes import c_char_p, CDLL
+
−from ctypes.util import find_library
+
−from django.contrib.gis.gdal.error import OGRException
+
−
+
−# Custom library path set?
+
−try:
+
−    from django.conf import settings
+
−    lib_path = settings.GDAL_LIBRARY_PATH
+
−except (AttributeError, EnvironmentError, ImportError):
+
−    lib_path = None
+
−
+
−if lib_path:
+
−    lib_names = None
+
−elif os.name == 'nt':
+
−    # Windows NT shared library
+
−    lib_names = ['gdal15']
+
−elif os.name == 'posix':
+
−    # *NIX library names.
+
−    lib_names = ['gdal', 'gdal1.5.0']
+
−else:
+
−    raise OGRException('Unsupported OS "%s"' % os.name)
+
−
+
−# Using the ctypes `find_library` utility  to find the 
+
−# path to the GDAL library from the list of library names.
+
−if lib_names:
+
−    for lib_name in lib_names:
+
−        lib_path = find_library(lib_name)
+
−        if not lib_path is None: break
+
−        
+
−if lib_path is None:
+
−    raise OGRException('Could not find the GDAL library (tried "%s"). '
+
−                       'Try setting GDAL_LIBRARY_PATH in your settings.' % 
+
−                       '", "'.join(lib_names))
+
−
+
−# This loads the GDAL/OGR C library
+
−lgdal = CDLL(lib_path)
+
−
+
−# On Windows, the GDAL binaries have some OSR routines exported with 
+
−# STDCALL, while others are not.  Thus, the library will also need to 
+
−# be loaded up as WinDLL for said OSR functions that require the 
+
−# different calling convention.
+
−if os.name == 'nt':
+
−    from ctypes import WinDLL
+
−    lwingdal = WinDLL(lib_path)
+
−
+
−def std_call(func):
+
−    """
+
−    Returns the correct STDCALL function for certain OSR routines on Win32
+
−    platforms.
+
−    """
+
−    if os.name == 'nt':
+
−        return lwingdal[func]
+
−    else:
+
−        return lgdal[func]
+
−
+
−#### Version-information functions. ####
+
−
+
−# Returns GDAL library version information with the given key.
+
−_version_info = std_call('GDALVersionInfo')
+
−_version_info.argtypes = [c_char_p]
+
−_version_info.restype = c_char_p
+
−
+
−def gdal_version():
+
−    "Returns only the GDAL version number information."
+
−    return _version_info('RELEASE_NAME')
+
−
+
−def gdal_full_version(): 
+
−    "Returns the full GDAL version information."
+
−    return _version_info('')
+
−
+
−def gdal_release_date(date=False): 
+
−    """
+
−    Returns the release date in a string format, e.g, "2007/06/27".
+
−    If the date keyword argument is set to True, a Python datetime object
+
−    will be returned instead.
+
−    """
+
−    from datetime import date as date_type
+
−    rel = _version_info('RELEASE_DATE')
+
−    yy, mm, dd = map(int, (rel[0:4], rel[4:6], rel[6:8]))
+
−    d = date_type(yy, mm, dd)
+
−    if date: return d
+
−    else: return d.strftime('%Y/%m/%d')