/* util.c - various utility functions
 *
 * Copyright (C) 2005-2010 Gerhard Häring <gh@ghaering.de>
 *
 * This file is part of pysqlite.
 *
 * This software is provided 'as-is', without any express or implied
 * warranty. In no event will the authors be held liable for any damages
 * arising from the use of this software.
 *
 * Permission is granted to anyone to use this software for any purpose,
 * including commercial applications, and to alter it and redistribute it
 * freely, subject to the following restrictions:
 *
 * 1. The origin of this software must not be misrepresented; you must not
 * claim that you wrote the original software. If you use this software
 * in a product, an acknowledgment in the product documentation would be
 * appreciated but is not required.
 * 2. Altered source versions must be plainly marked as such, and must not be
 * misrepresented as being the original software.
 * 3. This notice may not be removed or altered from any source distribution.
 */

#include "module.h"
#include "connection.h"

int pysqlite_step(sqlite3_stmt* statement, pysqlite_Connection* connection)
{
 int rc;

 if (statement == NULL) {
 /* this is a workaround for SQLite 3.5 and later. it now apparently
 * returns NULL for "no-operation" statements */
 rc = SQLITE_OK;
 } else {
 Py_BEGIN_ALLOW_THREADS
 rc = sqlite3_step(statement);
 Py_END_ALLOW_THREADS
 }

 return rc;
}

/**
 * Checks the SQLite error code and sets the appropriate DB-API exception.
 * Returns the error code (0 means no error occurred).
 */
int _pysqlite_seterror(sqlite3* db, sqlite3_stmt* st)
{
 int errorcode = sqlite3_errcode(db);

 switch (errorcode)
 {
 case SQLITE_OK:
 PyErr_Clear();
 break;
 case SQLITE_INTERNAL:
 case SQLITE_NOTFOUND:
 PyErr_SetString(pysqlite_InternalError, sqlite3_errmsg(db));
 break;
 case SQLITE_NOMEM:
 (void)PyErr_NoMemory();
 break;
 case SQLITE_ERROR:
 case SQLITE_PERM:
 case SQLITE_ABORT:
 case SQLITE_BUSY:
 case SQLITE_LOCKED:
 case SQLITE_READONLY:
 case SQLITE_INTERRUPT:
 case SQLITE_IOERR:
 case SQLITE_FULL:
 case SQLITE_CANTOPEN:
 case SQLITE_PROTOCOL:
 case SQLITE_EMPTY:
 case SQLITE_SCHEMA:
 PyErr_SetString(pysqlite_OperationalError, sqlite3_errmsg(db));
 break;
 case SQLITE_CORRUPT:
 PyErr_SetString(pysqlite_DatabaseError, sqlite3_errmsg(db));
 break;
 case SQLITE_TOOBIG:
 PyErr_SetString(pysqlite_DataError, sqlite3_errmsg(db));
 break;
 case SQLITE_CONSTRAINT:
 case SQLITE_MISMATCH:
 PyErr_SetString(pysqlite_IntegrityError, sqlite3_errmsg(db));
 break;
 case SQLITE_MISUSE:
 PyErr_SetString(pysqlite_ProgrammingError, sqlite3_errmsg(db));
 break;
 default:
 PyErr_SetString(pysqlite_DatabaseError, sqlite3_errmsg(db));
 break;
 }

 return errorcode;
}

#ifdef WORDS_BIGENDIAN
# define IS_LITTLE_ENDIAN 0
#else
# define IS_LITTLE_ENDIAN 1
#endif

PyObject *
_pysqlite_long_from_int64(sqlite_int64 value)
{
# if SIZEOF_LONG_LONG < 8
 if (value > PY_LLONG_MAX || value < PY_LLONG_MIN) {
 return _PyLong_FromByteArray(&value, sizeof(value),
 IS_LITTLE_ENDIAN, 1 /* signed */);
 }
# endif
# if SIZEOF_LONG < SIZEOF_LONG_LONG
 if (value > LONG_MAX || value < LONG_MIN)
 return PyLong_FromLongLong(value);
# endif
 return PyLong_FromLong(Py_SAFE_DOWNCAST(value, sqlite_int64, long));
}

sqlite_int64
_pysqlite_long_as_int64(PyObject * py_val)
{
 int overflow;
 long long value = PyLong_AsLongLongAndOverflow(py_val, &overflow);
 if (value == -1 && PyErr_Occurred())
 return -1;
 if (!overflow) {
# if SIZEOF_LONG_LONG > 8
 if (-0x8000000000000000LL <= value && value <= 0x7FFFFFFFFFFFFFFFLL)
# endif
 return value;
 }
 else if (sizeof(value) < sizeof(sqlite_int64)) {
 sqlite_int64 int64val;
 if (_PyLong_AsByteArray((PyLongObject *)py_val,
 (unsigned char *)&int64val, sizeof(int64val),
 IS_LITTLE_ENDIAN, 1 /* signed */) >= 0) {
 return int64val;
 }
 }
 PyErr_SetString(PyExc_OverflowError,
 "Python int too large to convert to SQLite INTEGER");
 return -1;
}