Files
pyDevSup/devsupApp/src/dbfield.c
Michael Davidsaver 864fbf531e cleanup device support
2013-03-30 16:08:14 -04:00

312 lines
7.5 KiB
C

/* python has its own ideas about which version to support */
#undef _POSIX_C_SOURCE
#undef _XOPEN_SOURCE
#include <Python.h>
#ifdef HAVE_NUMPY
#include <numpy/ndarrayobject.h>
#endif
#include <epicsVersion.h>
#include <dbCommon.h>
#include <dbAccess.h>
#include <dbStaticLib.h>
#include "pydevsup.h"
#ifdef HAVE_NUMPY
static int dbf2np_map[DBF_ENUM+1] = {
NPY_BYTE,
NPY_BYTE,
NPY_UBYTE,
NPY_INT16,
NPY_UINT16,
NPY_INT32,
NPY_UINT32,
NPY_FLOAT32,
NPY_FLOAT64,
NPY_INT16,
};
static PyArray_Descr* dbf2np[DBF_ENUM+1];
#endif
typedef struct {
PyObject_HEAD
DBADDR addr;
} pyField;
static int pyField_Init(pyField *self, PyObject *args, PyObject *kws)
{
const char *pvname;
if(!PyArg_ParseTuple(args, "s", &pvname))
return -1;
if(dbNameToAddr(pvname, &self->addr)) {
PyErr_SetString(PyExc_ValueError, "Record field not found");
return -1;
}
if(self->addr.field_type >= DBF_ENUM) {
PyErr_SetString(PyExc_ValueError, "Access to this field type is not supported");
return -1;
}
return 0;
}
static PyObject* pyField_name(pyField *self)
{
return Py_BuildValue("ss",
self->addr.precord->name,
self->addr.pfldDes->name);
}
static PyObject* pyField_fldinfo(pyField *self)
{
short dbf=self->addr.field_type;
short fsize=self->addr.field_size;
unsigned long nelm=self->addr.no_elements;
return Py_BuildValue("hhk", dbf, fsize, nelm);
}
union dbfvalue {
char dv_sval[MAX_STRING_SIZE];
epicsUInt32 dv_uval;
epicsInt32 dv_ival;
double dv_fval;
};
static PyObject* pyField_getval(pyField *self)
{
union dbfvalue buf;
long nReq = 1;
short reqtype;
switch(self->addr.field_type)
{
case DBF_CHAR:
case DBF_UCHAR:
case DBF_SHORT:
case DBF_USHORT:
case DBF_ENUM:
case DBF_LONG:
reqtype = DBF_LONG;
break;
case DBF_ULONG:
reqtype = DBF_ULONG;
break;
case DBF_FLOAT:
case DBF_DOUBLE:
reqtype = DBF_DOUBLE;
break;
case DBF_STRING:
reqtype = DBF_STRING;
break;
default:
PyErr_SetString(PyExc_ValueError, "Access to this field type is not supported");
return NULL;
}
if(dbGet(&self->addr, reqtype, buf.dv_sval, NULL, &nReq, NULL)) {
PyErr_SetString(PyExc_ValueError, "Error getting field value");
return NULL;
}
switch(reqtype) {
case DBF_LONG:
return PyInt_FromLong(buf.dv_ival);
case DBF_ULONG:
return PyInt_FromLong(buf.dv_uval);
case DBF_DOUBLE:
return PyInt_FromLong(buf.dv_fval);
case DBF_STRING:
return PyString_FromString(buf.dv_sval);
default:
Py_RETURN_NONE;
}
}
static PyObject* pyField_putval(pyField *self, PyObject* args)
{
PyObject *val;
union dbfvalue buf;
short puttype;
if(!PyArg_ParseTuple(args, "O", &val))
return NULL;
if(PyFloat_Check(val)) {
double v = PyFloat_AsDouble(val);
buf.dv_fval = v;
puttype = DBF_DOUBLE;
} else if(PyInt_Check(val)) {
long v = PyInt_AsLong(val);
if(v>0x7fffffffL) {
buf.dv_uval = v;
puttype = DBF_ULONG;
} else {
buf.dv_ival = v;
puttype = DBF_LONG;
}
} else if(PyString_Check(val)) {
const char *v = PyString_AsString(val);
strncpy(buf.dv_sval, v, MAX_STRING_SIZE);
buf.dv_sval[MAX_STRING_SIZE-1] = '\0';
puttype = DBF_STRING;
} else {
PyErr_SetString(PyExc_TypeError, "Unable to convert put type");
return NULL;
}
if(dbPut(&self->addr, puttype, buf.dv_sval, 1)){
PyErr_SetString(PyExc_ValueError, "Error putting field value");
return NULL;
}
Py_RETURN_NONE;
}
static PyObject *pyField_getarray(pyField *self)
{
#ifdef HAVE_NUMPY
int flags = NPY_CARRAY;
char *data=self->addr.pfield;
npy_int dims[1] = {self->addr.no_elements};
PyArray_Descr *desc;
if(self->addr.field_type>DBF_ENUM) {
PyErr_SetString(PyExc_TypeError, "Can not map field type to numpy type");
return NULL;
} else if(self->addr.field_type==DBF_STRING)
dims[0] *= self->addr.field_size;
desc = dbf2np[self->addr.field_type];
Py_XINCREF(desc);
return PyArray_NewFromDescr(&PyArray_Type, desc, 1, dims, NULL, data, flags, (PyObject*)self);
#else
PyErr_SetNone(PyExc_NotImplementedError);
return NULL;
#endif
}
static PyMethodDef pyField_methods[] = {
{"name", (PyCFunction)pyField_name, METH_NOARGS,
"Return Names (\"record\",\"field\")"},
{"fieldinfo", (PyCFunction)pyField_fldinfo, METH_NOARGS,
"Field type info\nReturn (type, size, #elements"},
{"getval", (PyCFunction)pyField_getval, METH_NOARGS,
"Returns scalar version of field value"},
{"putval", (PyCFunction)pyField_putval, METH_VARARGS,
"Sets field value from a scalar"},
{"getarray", (PyCFunction)pyField_getarray, METH_NOARGS,
"Return a numpy ndarray refering to this field for in-place operations."},
{NULL, NULL, 0, NULL}
};
static Py_ssize_t pyField_buf_getcount(pyField *self, Py_ssize_t *totallen)
{
if(totallen)
*totallen = self->addr.field_size * self->addr.no_elements;
return 1;
}
static Py_ssize_t pyField_buf_getbuf(pyField *self, Py_ssize_t bufid, void **data)
{
if(bufid!=0) {
PyErr_SetString(PyExc_SystemError, "Requested invalid segment");
return -1;
}
*data = self->addr.pfield;
return 0;
}
static Py_ssize_t pyField_buf_getcharbuf(pyField *self, Py_ssize_t bufid, char **data)
{
if(bufid!=0) {
PyErr_SetString(PyExc_SystemError, "Requested invalid segment");
return -1;
}
if(self->addr.field_size!=1) {
PyErr_SetString(PyExc_TypeError, "Field type must be CHAR or UCHAR");
return -1;
}
*data = self->addr.pfield;
return 0;
}
static int pyField_buf_getbufferproc(pyField *self, Py_buffer *buf, int flags)
{
return PyBuffer_FillInfo(buf, (PyObject*)self,
self->addr.pfield,
self->addr.field_size * self->addr.no_elements,
0, flags);
}
static PyBufferProcs pyField_buf_methods = {
(readbufferproc)pyField_buf_getbuf,
(writebufferproc)pyField_buf_getbuf,
(segcountproc)pyField_buf_getcount,
(charbufferproc)pyField_buf_getcharbuf,
(getbufferproc)pyField_buf_getbufferproc,
(releasebufferproc)NULL,
};
static PyTypeObject pyField_type = {
PyObject_HEAD_INIT(NULL)
0,
"_dbapi._Field",
sizeof(pyField),
};
int pyField_prepare(void)
{
size_t i;
pyField_type.tp_flags = Py_TPFLAGS_DEFAULT|Py_TPFLAGS_BASETYPE;
pyField_type.tp_flags |= Py_TPFLAGS_HAVE_GETCHARBUFFER|Py_TPFLAGS_HAVE_NEWBUFFER;
pyField_type.tp_methods = pyField_methods;
pyField_type.tp_as_buffer = &pyField_buf_methods;
pyField_type.tp_init = (initproc)pyField_Init;
pyField_type.tp_new = PyType_GenericNew;
if(PyType_Ready(&pyField_type)<0)
return -1;
import_array1(-1);
#ifdef HAVE_NUMPY
for(i=0; i<=DBF_ENUM; i++) {
dbf2np[i] = PyArray_DescrFromType(dbf2np_map[i]);
assert(dbf2np[i]);
}
#endif
return 0;
}
void pyField_setup(PyObject *module)
{
PyObject *typeobj=(PyObject*)&pyField_type;
Py_INCREF(typeobj);
PyModule_AddObject(module, "_Field", (PyObject*)&pyField_type);
}
void pyField_cleanup(void)
{
size_t i;
for(i=0; i<=DBF_ENUM; i++) {
Py_XDECREF(dbf2np[i]);
dbf2np[i] = NULL;
}
}