Python/symtable.c

#include "Python.h"
#include "compile.h"
#include "symtable.h"
#include "graminit.h"
#include "structmember.h"

PyObject *
PySymtableEntry_New(struct symtable *st, char *name, int type, int lineno)
{
	PySymtableEntryObject *ste = NULL;
	PyObject *k, *v;

	k = PyInt_FromLong(st->st_nscopes++);
	if (k == NULL)
		goto fail;
	v = PyDict_GetItem(st->st_symbols, k);
	if (v) /* XXX could check that name, type, lineno match */ {
		Py_INCREF(v);
		return v;
	}
	
	ste = (PySymtableEntryObject *)PyObject_New(PySymtableEntryObject,
						    &PySymtableEntry_Type);
	ste->ste_table = st;
	ste->ste_id = k;

	v = PyString_FromString(name);
	if (v == NULL)
		goto fail;
	ste->ste_name = v;
	
	v = PyDict_New();
	if (v == NULL)
	    goto fail;
	ste->ste_symbols = v;

	v = PyList_New(0);
	if (v == NULL)
	    goto fail;
	ste->ste_varnames = v;

	v = PyList_New(0);
	if (v == NULL)
	    goto fail;
	ste->ste_children = v;

	ste->ste_optimized = 0;
	ste->ste_lineno = lineno;
	switch (type) {
	case funcdef:
	case lambdef:
		ste->ste_type = TYPE_FUNCTION;
		break;
	case classdef:
		ste->ste_type = TYPE_CLASS;
		break;
	case single_input:
	case eval_input:
	case file_input:
		ste->ste_type = TYPE_MODULE;
		break;
	}

	if (st->st_cur == NULL)
		ste->ste_nested = 0;
	else if (st->st_cur->ste_nested 
		 || st->st_cur->ste_type == TYPE_FUNCTION)
		ste->ste_nested = 1;
	else
		ste->ste_nested = 0;
	ste->ste_child_free = 0;

	if (PyDict_SetItem(st->st_symbols, ste->ste_id, (PyObject *)ste) < 0)
	    goto fail;
	
	return (PyObject *)ste;
 fail:
	Py_XDECREF(ste);
	return NULL;
}

static PyObject *
ste_repr(PySymtableEntryObject *ste)
{
	char buf[256];

	sprintf(buf, "<symtable entry %.100s(%ld), line %d>",
		PyString_AS_STRING(ste->ste_name),
		PyInt_AS_LONG(ste->ste_id),
		ste->ste_lineno);
	return PyString_FromString(buf);
}

static void
ste_dealloc(PySymtableEntryObject *ste)
{
	ste->ste_table = NULL;
	Py_XDECREF(ste->ste_id);
	Py_XDECREF(ste->ste_name);
	Py_XDECREF(ste->ste_symbols);
	Py_XDECREF(ste->ste_varnames);
	Py_XDECREF(ste->ste_children);
	PyObject_Del(ste);
}

#define OFF(x) offsetof(PySymtableEntryObject, x)

static struct memberlist ste_memberlist[] = {
	{"id",       T_OBJECT, OFF(ste_id), READONLY},
	{"name",     T_OBJECT, OFF(ste_name), READONLY},
	{"symbols",  T_OBJECT, OFF(ste_symbols), READONLY},
	{"varnames", T_OBJECT, OFF(ste_varnames), READONLY},
	{"children", T_OBJECT, OFF(ste_children), READONLY},
	{"type",     T_INT,    OFF(ste_type), READONLY},
	{"lineno",   T_INT,    OFF(ste_lineno), READONLY},
	{"optimized",T_INT,    OFF(ste_optimized), READONLY},
	{"nested",   T_INT,    OFF(ste_nested), READONLY},
	{NULL}
};

static PyObject *
ste_getattr(PySymtableEntryObject *ste, char *name)
{
	return PyMember_Get((char *)ste, ste_memberlist, name);
}

PyTypeObject PySymtableEntry_Type = {
	PyObject_HEAD_INIT(&PyType_Type)
	0,
	"symtable entry",
	sizeof(PySymtableEntryObject),
	0,
	(destructor)ste_dealloc,                /* tp_dealloc */
	0,                                      /* tp_print */
	(getattrfunc)ste_getattr,               /* tp_getattr */
	0,					/* tp_setattr */
	0,			                /* tp_compare */
	(reprfunc)ste_repr,			/* tp_repr */
	0,					/* tp_as_number */
	0,			                /* tp_as_sequence */
	0,					/* tp_as_mapping */
	0,					/* tp_hash */
	0,					/* tp_call */
	0,					/* tp_str */
	0,					/* tp_getattro */
	0,					/* tp_setattro */
	0,					/* tp_as_buffer */
	Py_TPFLAGS_DEFAULT,	                /* tp_flags */
 	0,					/* tp_doc */
};