view Python/structmember.c @ 42817:5355337709e1

Implementation of PEP 3101, Advanced String Formatting. Known issues: The string.Formatter class, as discussed in the PEP, is incomplete. Error handling needs to conform to the PEP. Need to fix this warning that I introduced in Python/formatter_unicode.c: Objects/stringlib/unicodedefs.h:26: warning: `STRINGLIB_CMP' defined but not used Need to make sure sign formatting is correct, more tests needed. Need to remove '()' sign formatting, left over from an earlier version of the PEP.
author Eric Smith <eric@trueblade.com>
date Sat, 25 Aug 2007 02:26:07 +0000
parents 0fcc18aba385
children dd03aa741f56
line wrap: on
line source


/* Map C struct members to Python object attributes */

#include "Python.h"

#include "structmember.h"

PyObject *
PyMember_GetOne(const char *addr, PyMemberDef *l)
{
	PyObject *v;

	addr += l->offset;
	switch (l->type) {
	case T_BYTE:
		v = PyInt_FromLong(*(char*)addr);
		break;
	case T_UBYTE:
		v = PyLong_FromUnsignedLong(*(unsigned char*)addr);
		break;
	case T_SHORT:
		v = PyInt_FromLong(*(short*)addr);
		break;
	case T_USHORT:
		v = PyLong_FromUnsignedLong(*(unsigned short*)addr);
		break;
	case T_INT:
		v = PyInt_FromLong(*(int*)addr);
		break;
	case T_UINT:
		v = PyLong_FromUnsignedLong(*(unsigned int*)addr);
		break;
	case T_LONG:
		v = PyInt_FromLong(*(long*)addr);
		break;
	case T_ULONG:
		v = PyLong_FromUnsignedLong(*(unsigned long*)addr);
		break;
	case T_PYSSIZET:
		v = PyInt_FromSsize_t(*(Py_ssize_t*)addr);
		break;
	case T_FLOAT:
		v = PyFloat_FromDouble((double)*(float*)addr);
		break;
	case T_DOUBLE:
		v = PyFloat_FromDouble(*(double*)addr);
		break;
	case T_STRING:
		if (*(char**)addr == NULL) {
			Py_INCREF(Py_None);
			v = Py_None;
		}
		else
			v = PyString_FromString(*(char**)addr);
		break;
	case T_STRING_INPLACE:
		v = PyString_FromString((char*)addr);
		break;
	case T_CHAR:
		v = PyString_FromStringAndSize((char*)addr, 1);
		break;
	case T_OBJECT:
		v = *(PyObject **)addr;
		if (v == NULL)
			v = Py_None;
		Py_INCREF(v);
		break;
	case T_OBJECT_EX:
		v = *(PyObject **)addr;
		if (v == NULL)
			PyErr_SetString(PyExc_AttributeError, l->name);
		Py_XINCREF(v);
		break;
#ifdef HAVE_LONG_LONG
	case T_LONGLONG:
		v = PyLong_FromLongLong(*(PY_LONG_LONG *)addr);
		break;
	case T_ULONGLONG:
		v = PyLong_FromUnsignedLongLong(*(unsigned PY_LONG_LONG *)addr);
		break;
#endif /* HAVE_LONG_LONG */
        case T_NONE:
		v = Py_None;
		Py_INCREF(v);
		break;
	default:
		PyErr_SetString(PyExc_SystemError, "bad memberdescr type");
		v = NULL;
	}
	return v;
}

#define WARN(msg)						\
    do {							\
	if (PyErr_WarnEx(PyExc_RuntimeWarning, msg, 1) < 0)	\
		return -1;					\
    } while (0)

int
PyMember_SetOne(char *addr, PyMemberDef *l, PyObject *v)
{
	PyObject *oldv;

	if ((l->flags & READONLY) || l->type == T_STRING)
	{
		PyErr_SetString(PyExc_AttributeError, "readonly attribute");
		return -1;
	}
	if (v == NULL && l->type != T_OBJECT_EX && l->type != T_OBJECT) {
		PyErr_SetString(PyExc_TypeError,
				"can't delete numeric/char attribute");
		return -1;
	}
	addr += l->offset;
	switch (l->type) {
	case T_BYTE:{
		long long_val = PyInt_AsLong(v);
		if ((long_val == -1) && PyErr_Occurred())
			return -1;
		*(char*)addr = (char)long_val;
		/* XXX: For compatibility, only warn about truncations
		   for now. */
		if ((long_val > CHAR_MAX) || (long_val < CHAR_MIN))
			WARN("Truncation of value to char");
		break;
		}
	case T_UBYTE:{
		long long_val = PyInt_AsLong(v);
		if ((long_val == -1) && PyErr_Occurred())
			return -1;
		*(unsigned char*)addr = (unsigned char)long_val;
		if ((long_val > UCHAR_MAX) || (long_val < 0))
			WARN("Truncation of value to unsigned char");
		break;
		}
	case T_SHORT:{
		long long_val = PyInt_AsLong(v);
		if ((long_val == -1) && PyErr_Occurred())
			return -1;
		*(short*)addr = (short)long_val;
		if ((long_val > SHRT_MAX) || (long_val < SHRT_MIN))
			WARN("Truncation of value to short");
		break;
		}
	case T_USHORT:{
		long long_val = PyInt_AsLong(v);
		if ((long_val == -1) && PyErr_Occurred())
			return -1;
		*(unsigned short*)addr = (unsigned short)long_val;
		if ((long_val > USHRT_MAX) || (long_val < 0))
			WARN("Truncation of value to unsigned short");
		break;
		}
  	case T_INT:{
		long long_val = PyInt_AsLong(v);
		if ((long_val == -1) && PyErr_Occurred())
			return -1;
		*(int *)addr = (int)long_val;
		if ((long_val > INT_MAX) || (long_val < INT_MIN))
			WARN("Truncation of value to int");
		break;
		}
	case T_UINT:{
		unsigned long ulong_val = PyLong_AsUnsignedLong(v);
		if ((ulong_val == (unsigned int)-1) && PyErr_Occurred()) {
			/* XXX: For compatibility, accept negative int values
			   as well. */
			PyErr_Clear();
			ulong_val = PyLong_AsLong(v);
			if ((ulong_val == (unsigned int)-1) && PyErr_Occurred())
				return -1;
			*(unsigned int *)addr = (unsigned int)ulong_val;
			WARN("Writing negative value into unsigned field");
		} else
			*(unsigned int *)addr = (unsigned int)ulong_val;
		if (ulong_val > UINT_MAX)
			WARN("Truncation of value to unsigned int");
		break;
		}
	case T_LONG:{
		*(long*)addr = PyLong_AsLong(v);
		if ((*(long*)addr == -1) && PyErr_Occurred())
			return -1;
		break;
		}
	case T_ULONG:{
		*(unsigned long*)addr = PyLong_AsUnsignedLong(v);
		if ((*(unsigned long*)addr == (unsigned long)-1)
		    && PyErr_Occurred()) {
			/* XXX: For compatibility, accept negative int values
			   as well. */
			PyErr_Clear();
			*(unsigned long*)addr = PyLong_AsLong(v);
			if ((*(unsigned long*)addr == (unsigned int)-1)
			    && PyErr_Occurred())
				return -1;
			WARN("Writing negative value into unsigned field");
		}
		break;
		}
	case T_PYSSIZET:{
		*(Py_ssize_t*)addr = PyInt_AsSsize_t(v);
		if ((*(Py_ssize_t*)addr == (Py_ssize_t)-1)
		    && PyErr_Occurred())
				return -1;
		break;
		}
	case T_FLOAT:{
		double double_val = PyFloat_AsDouble(v);
		if ((double_val == -1) && PyErr_Occurred())
			return -1;
		*(float*)addr = (float)double_val;
		break;
		}
	case T_DOUBLE:
		*(double*)addr = PyFloat_AsDouble(v);
		if ((*(double*)addr == -1) && PyErr_Occurred())
			return -1;
		break;
	case T_OBJECT:
	case T_OBJECT_EX:
		Py_XINCREF(v);
		oldv = *(PyObject **)addr;
		*(PyObject **)addr = v;
		Py_XDECREF(oldv);
		break;
	case T_CHAR:
		if (PyString_Check(v) && PyString_Size(v) == 1) {
			*(char*)addr = PyString_AsString(v)[0];
		}
		else {
			PyErr_BadArgument();
			return -1;
		}
		break;
#ifdef HAVE_LONG_LONG
	case T_LONGLONG:{
		PY_LONG_LONG value;
		*(PY_LONG_LONG*)addr = value = PyLong_AsLongLong(v);
		if ((value == -1) && PyErr_Occurred())
			return -1;
		break;
		}
	case T_ULONGLONG:{
		unsigned PY_LONG_LONG value;
		/* ??? PyLong_AsLongLong accepts an int, but PyLong_AsUnsignedLongLong
			doesn't ??? */
		if (PyLong_Check(v))
			*(unsigned PY_LONG_LONG*)addr = value = PyLong_AsUnsignedLongLong(v);
		else
			*(unsigned PY_LONG_LONG*)addr = value = PyInt_AsLong(v);
		if ((value == (unsigned PY_LONG_LONG)-1) && PyErr_Occurred())
			return -1;
		break;
		}
#endif /* HAVE_LONG_LONG */
	default:
		PyErr_Format(PyExc_SystemError,
			     "bad memberdescr type for %s", l->name);
		return -1;
	}
	return 0;
}