view Python/structmember.c @ 58707:76cf60e2d005 legacy-trunk

normalize exceptions passed to the __exit__ method #7853 In Python 2.x, exceptions in finally blocks are not normalized. Since with statements are implemented using finally blocks, ceval.c had to be tweaked to distinguish between with finally blocks and normal ones. A test for the finalization of generators containing with statements was also added.
author Benjamin Peterson <benjamin@python.org>
date Fri, 05 Feb 2010 02:12:14 +0000
parents 96a2371b114b
children 66b60a6e8198 e808fc548cd6
line wrap: on
line source


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

#include "Python.h"

#include "structmember.h"

static PyObject *
listmembers(struct memberlist *mlist)
{
	int i, n;
	PyObject *v;
	for (n = 0; mlist[n].name != NULL; n++)
		;
	v = PyList_New(n);
	if (v != NULL) {
		for (i = 0; i < n; i++)
			PyList_SetItem(v, i,
				       PyString_FromString(mlist[i].name));
		if (PyErr_Occurred()) {
			Py_DECREF(v);
			v = NULL;
		}
		else {
			PyList_Sort(v);
		}
	}
	return v;
}

PyObject *
PyMember_Get(const char *addr, struct memberlist *mlist, const char *name)
{
	struct memberlist *l;

	if (strcmp(name, "__members__") == 0)
		return listmembers(mlist);
	for (l = mlist; l->name != NULL; l++) {
		if (strcmp(l->name, name) == 0) {
			PyMemberDef copy;
			copy.name = l->name;
			copy.type = l->type;
			copy.offset = l->offset;
			copy.flags = l->flags;
			copy.doc = NULL;
			return PyMember_GetOne(addr, &copy);
		}
	}
	PyErr_SetString(PyExc_AttributeError, name);
	return NULL;
}

PyObject *
PyMember_GetOne(const char *addr, PyMemberDef *l)
{
	PyObject *v;
	if ((l->flags & READ_RESTRICTED) &&
	    PyEval_GetRestricted()) {
		PyErr_SetString(PyExc_RuntimeError, "restricted attribute");
		return NULL;
	}
	addr += l->offset;
	switch (l->type) {
	case T_BOOL:
		v = PyBool_FromLong(*(char*)addr);
		break;
	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 */
	default:
		PyErr_SetString(PyExc_SystemError, "bad memberdescr type");
		v = NULL;
	}
	return v;
}

int
PyMember_Set(char *addr, struct memberlist *mlist, const char *name, PyObject *v)
{
	struct memberlist *l;

	for (l = mlist; l->name != NULL; l++) {
		if (strcmp(l->name, name) == 0) {
			PyMemberDef copy;
			copy.name = l->name;
			copy.type = l->type;
			copy.offset = l->offset;
			copy.flags = l->flags;
			copy.doc = NULL;
			return PyMember_SetOne(addr, &copy, v);
		}
	}

	PyErr_SetString(PyExc_AttributeError, name);
	return -1;
}

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

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

	addr += l->offset;

	if ((l->flags & READONLY) || l->type == T_STRING)
	{
		PyErr_SetString(PyExc_TypeError, "readonly attribute");
		return -1;
	}
	if ((l->flags & PY_WRITE_RESTRICTED) && PyEval_GetRestricted()) {
		PyErr_SetString(PyExc_RuntimeError, "restricted attribute");
		return -1;
	}
	if (v == NULL) {
		if (l->type == T_OBJECT_EX) {
			/* Check if the attribute is set. */
			if (*(PyObject **)addr == NULL) {
				PyErr_SetString(PyExc_AttributeError, l->name);
				return -1;
			}
		}
		else if (l->type != T_OBJECT) {
			PyErr_SetString(PyExc_TypeError,
					"can't delete numeric/char attribute");
			return -1;
		}
	}
	switch (l->type) {
	case T_BOOL:{
		if (!PyBool_Check(v)) {
			PyErr_SetString(PyExc_TypeError,
					"attribute value type must be bool");
			return -1;
		}
		if (v == Py_True)
			*(char*)addr = (char) 1;
		else
			*(char*)addr = (char) 0;
		break;
		}
	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;
}