--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/app/django/contrib/gis/geos/prototypes/coordseq.py	Tue Oct 14 16:00:59 2008 +0000
@@ -0,0 +1,82 @@
+from ctypes import c_double, c_int, c_uint, POINTER
+from django.contrib.gis.geos.libgeos import lgeos, GEOM_PTR, CS_PTR
+from django.contrib.gis.geos.prototypes.errcheck import last_arg_byref, GEOSException
+
+## Error-checking routines specific to coordinate sequences. ##
+def check_cs_ptr(result, func, cargs):
+    "Error checking on routines that return Geometries."
+    if not result:
+        raise GEOSException('Error encountered checking Coordinate Sequence returned from GEOS C function "%s".' % func.__name__)
+    return result
+
+def check_cs_op(result, func, cargs):
+    "Checks the status code of a coordinate sequence operation."
+    if result == 0:
+        raise GEOSException('Could not set value on coordinate sequence')
+    else:
+        return result
+
+def check_cs_get(result, func, cargs):
+    "Checking the coordinate sequence retrieval."
+    check_cs_op(result, func, cargs)
+    # Object in by reference, return its value.
+    return last_arg_byref(cargs)
+
+## Coordinate sequence prototype generation functions. ##
+def cs_int(func):
+    "For coordinate sequence routines that return an integer."
+    func.argtypes = [CS_PTR, POINTER(c_uint)]
+    func.restype = c_int
+    func.errcheck = check_cs_get
+    return func
+
+def cs_operation(func, ordinate=False, get=False):
+    "For coordinate sequence operations."
+    if get:
+        # Get routines get double parameter passed-in by reference.
+        func.errcheck = check_cs_get
+        dbl_param = POINTER(c_double)
+    else:
+        func.errcheck = check_cs_op
+        dbl_param = c_double
+
+    if ordinate:
+        # Get/Set ordinate routines have an extra uint parameter.
+        func.argtypes = [CS_PTR, c_uint, c_uint, dbl_param]
+    else:
+        func.argtypes = [CS_PTR, c_uint, dbl_param]
+
+    func.restype = c_int
+    return func
+
+def cs_output(func, argtypes):
+    "For routines that return a coordinate sequence."
+    func.argtypes = argtypes
+    func.restype = CS_PTR
+    func.errcheck = check_cs_ptr
+    return func
+
+## Coordinate Sequence ctypes prototypes ##
+
+# Coordinate Sequence constructors & cloning.
+cs_clone = cs_output(lgeos.GEOSCoordSeq_clone, [CS_PTR])
+create_cs = cs_output(lgeos.GEOSCoordSeq_create, [c_uint, c_uint])
+get_cs = cs_output(lgeos.GEOSGeom_getCoordSeq, [GEOM_PTR])
+
+# Getting, setting ordinate
+cs_getordinate = cs_operation(lgeos.GEOSCoordSeq_getOrdinate, ordinate=True, get=True)
+cs_setordinate = cs_operation(lgeos.GEOSCoordSeq_setOrdinate, ordinate=True)
+
+# For getting, x, y, z
+cs_getx = cs_operation(lgeos.GEOSCoordSeq_getX, get=True)
+cs_gety = cs_operation(lgeos.GEOSCoordSeq_getY, get=True)
+cs_getz = cs_operation(lgeos.GEOSCoordSeq_getZ, get=True)
+
+# For setting, x, y, z
+cs_setx = cs_operation(lgeos.GEOSCoordSeq_setX)
+cs_sety = cs_operation(lgeos.GEOSCoordSeq_setY)
+cs_setz = cs_operation(lgeos.GEOSCoordSeq_setZ)
+
+# These routines return size & dimensions.
+cs_getsize = cs_int(lgeos.GEOSCoordSeq_getSize)
+cs_getdims = cs_int(lgeos.GEOSCoordSeq_getDimensions)