cpython/Python/structmember.c

330 lines
7.6 KiB
C

/* 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;
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;
}
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;
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;
}