"""ctypes abstraction layer
We keep rewriting functions as the main entry points change,
so let's just localise the changes here...
"""
import ctypes, logging, os
log = logging.getLogger( 'OpenGL.platform.ctypesloader' )
#log.setLevel( logging.DEBUG )
ctypes_version = [
int(x) for x in ctypes.__version__.split('.')
]
from ctypes import util
import OpenGL
DLL_DIRECTORY = os.path.join( os.path.dirname( OpenGL.__file__ ), 'DLLS' )
def loadLibrary( dllType, name, mode = ctypes.RTLD_GLOBAL ):
"""Load a given library by name with the given mode
dllType -- the standard ctypes pointer to a dll type, such as
ctypes.cdll or ctypes.windll or the underlying ctypes.CDLL or
ctypes.WinDLL classes.
name -- a short module name, e.g. 'GL' or 'GLU'
mode -- ctypes.RTLD_GLOBAL or ctypes.RTLD_LOCAL,
controls whether the module resolves names via other
modules already loaded into this process. GL modules
generally need to be loaded with GLOBAL flags
returns the ctypes C-module object
"""
if ctypes_version <= [0,9,9,3]:
raise RuntimeError(
"""Unsupported ctypes version (%s), please upgrade to ctypes 1.x or above"""%(
".".join( [str(x) for x in ctypes_version] ),
)
)
if isinstance( dllType, ctypes.LibraryLoader ):
dllType = dllType._dlltype
fullName = None
try:
fullName = util.find_library( name )
if fullName is not None:
name = fullName
elif os.path.isfile( os.path.join( DLL_DIRECTORY, name + '.dll' )):
name = os.path.join( DLL_DIRECTORY, name + '.dll' )
except Exception, err:
log.info( '''Failed on util.find_library( %r ): %s''', name, err )
# Should the call fail, we just try to load the base filename...
pass
try:
return dllType( name, mode )
except Exception, err:
err.args += (name,fullName)
raise
def buildFunction( functionType, name, dll ):
"""Abstract away the ctypes function-creation operation"""
if ctypes_version <= [0,9,9,3]:
raise RuntimeError(
"""Unsupported ctypes version (%s), please upgrade to 1.x or above"""%(
".".join( [str(x) for x in ctypes_version] ),
)
)
return functionType( (name, dll), )
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