psycopg2/psycopg/typecast_basic.c

/* pgcasts_basic.c - basic typecasting functions to python types
 *
 * Copyright (C) 2001-2010 Federico Di Gregorio <fog@debian.org>
 *
 * This file is part of psycopg.
 *
 * psycopg2 is free software: you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as published
 * by the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * In addition, as a special exception, the copyright holders give
 * permission to link this program with the OpenSSL library (or with
 * modified versions of OpenSSL that use the same license as OpenSSL),
 * and distribute linked combinations including the two.
 *
 * You must obey the GNU Lesser General Public License in all respects for
 * all of the code used other than OpenSSL.
 *
 * psycopg2 is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
 * License for more details.
 */

/** INTEGER - cast normal integers (4 bytes) to python int **/

static PyObject *
typecast_INTEGER_cast(const char *s, Py_ssize_t len, PyObject *curs)
{
    char buffer[12];

    if (s == NULL) {Py_INCREF(Py_None); return Py_None;}
    if (s[len] != '\0') {
        strncpy(buffer, s, (size_t) len); buffer[len] = '\0';
        s = buffer;
    }
    return PyInt_FromString((char *)s, NULL, 0);
}

/** LONGINTEGER - cast long integers (8 bytes) to python long **/

static PyObject *
typecast_LONGINTEGER_cast(const char *s, Py_ssize_t len, PyObject *curs)
{
    char buffer[24];

    if (s == NULL) {Py_INCREF(Py_None); return Py_None;}
    if (s[len] != '\0') {
        strncpy(buffer, s, (size_t) len); buffer[len] = '\0';
        s = buffer;
    }
    return PyLong_FromString((char *)s, NULL, 0);
}

/** FLOAT - cast floating point numbers to python float **/

static PyObject *
typecast_FLOAT_cast(const char *s, Py_ssize_t len, PyObject *curs)
{
    PyObject *str = NULL, *flo = NULL;
    char *pend;

    if (s == NULL) {Py_INCREF(Py_None); return Py_None;}
    str = PyString_FromStringAndSize(s, len);
    flo = PyFloat_FromString(str, &pend);
    Py_DECREF(str);
    return flo;
}

/** STRING - cast strings of any type to python string **/

static PyObject *
typecast_STRING_cast(const char *s, Py_ssize_t len, PyObject *curs)
{
    if (s == NULL) {Py_INCREF(Py_None); return Py_None;}
    return PyString_FromStringAndSize(s, len);
}

/** UNICODE - cast strings of any type to a python unicode object **/

static PyObject *
typecast_UNICODE_cast(const char *s, Py_ssize_t len, PyObject *curs)
{
    PyObject *enc;

    if (s == NULL) {Py_INCREF(Py_None); return Py_None;}

    enc = PyDict_GetItemString(psycoEncodings,
                               ((cursorObject*)curs)->conn->encoding);
    if (enc) {
        return PyUnicode_Decode(s, len, PyString_AsString(enc), NULL);
    }
    else {
       PyErr_Format(InterfaceError,
                    "can't decode into unicode string from %s",
                    ((cursorObject*)curs)->conn->encoding);
       return NULL;
    }
}

/** BOOLEAN - cast boolean value into right python object **/

static PyObject *
typecast_BOOLEAN_cast(const char *s, Py_ssize_t len, PyObject *curs)
{
    PyObject *res;

    if (s == NULL) {Py_INCREF(Py_None); return Py_None;}

    if (s[0] == 't')
        res = Py_True;
    else
        res = Py_False;

    Py_INCREF(res);
    return res;
}

/** DECIMAL - cast any kind of number into a Python Decimal object **/

static PyObject *
typecast_DECIMAL_cast(const char *s, Py_ssize_t len, PyObject *curs)
{
    PyObject *res = NULL;
    PyObject *decimalType;
    char *buffer;

    if (s == NULL) {Py_INCREF(Py_None); return Py_None;}

    if ((buffer = PyMem_Malloc(len+1)) == NULL)
        return PyErr_NoMemory();
    strncpy(buffer, s, (size_t) len); buffer[len] = '\0';
    decimalType = psyco_GetDecimalType();
    /* Fall back on float if decimal is not available */
    if (decimalType != NULL) {
        res = PyObject_CallFunction(decimalType, "s", buffer);
        Py_DECREF(decimalType);
    }
    else {
        res = PyObject_CallFunction((PyObject*)&PyFloat_Type, "s", buffer);
    }
    PyMem_Free(buffer);

    return res;
}

/* some needed aliases */
#define typecast_NUMBER_cast   typecast_FLOAT_cast
#define typecast_ROWID_cast    typecast_INTEGER_cast