Tools/bgen/bgen/bgenObjectDefinition.py

   1 from bgenOutput import *
   2 from bgenGeneratorGroup import GeneratorGroup
   3
   4 class ObjectDefinition(GeneratorGroup):
   5         "Spit out code that together defines a new Python object type"
   6
   7         def __init__(self, name, prefix, itselftype):
   8                 """ObjectDefinition constructor.  May be extended, but do not override.
   9
  10                 - name: the object's official name, e.g. 'SndChannel'.
  11                 - prefix: the prefix used for the object's functions and data, e.g. 'SndCh'.
  12                 - itselftype: the C type actually contained in the object, e.g. 'SndChannelPtr'.
  13
  14                 XXX For official Python data types, rules for the 'Py' prefix are a problem.
  15                 """
  16
  17                 GeneratorGroup.__init__(self, prefix or name)
  18                 self.name = name
  19                 self.itselftype = itselftype
  20                 self.objecttype = name + 'Object'
  21                 self.typename = name + '_Type'
  22                 self.argref = ""        # set to "*" if arg to <type>_New should be pointer
  23                 self.static = "static " # set to "" to make <type>_New and <type>_Convert public
  24                 self.basechain = "NULL" # set to &<basetype>_chain to chain methods
  25
  26         def add(self, g):
  27                 g.setselftype(self.objecttype, self.itselftype)
  28                 GeneratorGroup.add(self, g)
  29
  30         def reference(self):
  31                 # In case we are referenced from a module
  32                 pass
  33
  34         def generate(self):
  35                 # XXX This should use long strings and %(varname)s substitution!
  36
  37                 OutHeader2("Object type " + self.name)
  38
  39                 sf = self.static and "staticforward "
  40                 Output("%sPyTypeObject %s;", sf, self.typename)
  41                 Output()
  42                 Output("#define %s_Check(x) ((x)->ob_type == &%s)",
  43                        self.prefix, self.typename)
  44                 Output()
  45                 Output("typedef struct %s {", self.objecttype)
  46                 IndentLevel()
  47                 Output("PyObject_HEAD")
  48                 self.outputStructMembers()
  49                 DedentLevel()
  50                 Output("} %s;", self.objecttype)
  51
  52                 self.outputNew()
  53
  54                 self.outputConvert()
  55
  56                 self.outputDealloc()
  57
  58                 GeneratorGroup.generate(self)
  59
  60                 Output()
  61                 Output("%sPyMethodChain %s_chain = { %s_methods, %s };",
  62                         self.static,    self.prefix, self.prefix, self.basechain)
  63
  64                 self.outputGetattr()
  65
  66                 self.outputSetattr()
  67
  68                 self.outputTypeObject()
  69
  70                 OutHeader2("End object type " + self.name)
  71
  72         def outputStructMembers(self):
  73                 Output("%s ob_itself;", self.itselftype)
  74
  75         def outputNew(self):
  76                 Output()
  77                 Output("%sPyObject *%s_New(itself)", self.static, self.prefix)
  78                 IndentLevel()
  79                 Output("%s %sitself;", self.itselftype, self.argref)
  80                 DedentLevel()
  81                 OutLbrace()
  82                 Output("%s *it;", self.objecttype)
  83                 self.outputCheckNewArg()
  84                 Output("it = PyObject_NEW(%s, &%s);", self.objecttype, self.typename)
  85                 Output("if (it == NULL) return NULL;")
  86                 self.outputInitStructMembers()
  87                 Output("return (PyObject *)it;")
  88                 OutRbrace()
  89
  90         def outputInitStructMembers(self):
  91                 Output("it->ob_itself = %sitself;", self.argref)
  92
  93         def outputCheckNewArg(self):
  94                         "Override this method to apply additional checks/conversions"
  95
  96         def outputConvert(self):
  97                 Output("%s%s_Convert(v, p_itself)", self.static, self.prefix)
  98                 IndentLevel()
  99                 Output("PyObject *v;")
 100                 Output("%s *p_itself;", self.itselftype)
 101                 DedentLevel()
 102                 OutLbrace()
 103                 self.outputCheckConvertArg()
 104                 Output("if (!%s_Check(v))", self.prefix)
 105                 OutLbrace()
 106                 Output('PyErr_SetString(PyExc_TypeError, "%s required");', self.name)
 107                 Output("return 0;")
 108                 OutRbrace()
 109                 Output("*p_itself = ((%s *)v)->ob_itself;", self.objecttype)
 110                 Output("return 1;")
 111                 OutRbrace()
 112
 113         def outputCheckConvertArg(self):
 114                 "Override this method to apply additional conversions"
 115
 116         def outputDealloc(self):
 117                 Output()
 118                 Output("static void %s_dealloc(self)", self.prefix)
 119                 IndentLevel()
 120                 Output("%s *self;", self.objecttype)
 121                 DedentLevel()
 122                 OutLbrace()
 123                 self.outputCleanupStructMembers()
 124                 Output("PyMem_DEL(self);")
 125                 OutRbrace()
 126
 127         def outputCleanupStructMembers(self):
 128                 self.outputFreeIt("self->ob_itself")
 129
 130         def outputFreeIt(self, name):
 131                 Output("/* Cleanup of %s goes here */", name)
 132
 133         def outputGetattr(self):
 134                 Output()
 135                 Output("static PyObject *%s_getattr(self, name)", self.prefix)
 136                 IndentLevel()
 137                 Output("%s *self;", self.objecttype)
 138                 Output("char *name;")
 139                 DedentLevel()
 140                 OutLbrace()
 141                 self.outputGetattrBody()
 142                 OutRbrace()
 143
 144         def outputGetattrBody(self):
 145                 self.outputGetattrHook()
 146                 Output("return Py_FindMethodInChain(&%s_chain, (PyObject *)self, name);",
 147                        self.prefix)
 148
 149         def outputGetattrHook(self):
 150                 pass
 151
 152         def outputSetattr(self):
 153                 Output()
 154                 Output("#define %s_setattr NULL", self.prefix)
 155
 156         def outputTypeObject(self):
 157                 sf = self.static and "staticforward "
 158                 Output()
 159                 Output("%sPyTypeObject %s = {", sf, self.typename)
 160                 IndentLevel()
 161                 Output("PyObject_HEAD_INIT(&PyType_Type)")
 162                 Output("0, /*ob_size*/")
 163                 Output("\"%s\", /*tp_name*/", self.name)
 164                 Output("sizeof(%s), /*tp_basicsize*/", self.objecttype)
 165                 Output("0, /*tp_itemsize*/")
 166                 Output("/* methods */")
 167                 Output("(destructor) %s_dealloc, /*tp_dealloc*/", self.prefix)
 168                 Output("0, /*tp_print*/")
 169                 Output("(getattrfunc) %s_getattr, /*tp_getattr*/", self.prefix)
 170                 Output("(setattrfunc) %s_setattr, /*tp_setattr*/", self.prefix)
 171                 DedentLevel()
 172                 Output("};")
 173
 174
 175 class GlobalObjectDefinition(ObjectDefinition):
 176         """Like ObjectDefinition but exports some parts.
 177
 178         XXX Should also somehow generate a .h file for them.
 179         """
 180
 181         def __init__(self, name, prefix = None, itselftype = None):
 182                 ObjectDefinition.__init__(self, name, prefix or name, itselftype or name)
 183                 self.static = ""