cpython/Modules/_sqlite/statement.c

531 lines
16 KiB
C

/* statement.c - the statement type
*
* 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 "statement.h"
#include "cursor.h"
#include "connection.h"
#include "microprotocols.h"
#include "prepare_protocol.h"
#include "util.h"
/* prototypes */
static int pysqlite_check_remaining_sql(const char* tail);
typedef enum {
LINECOMMENT_1,
IN_LINECOMMENT,
COMMENTSTART_1,
IN_COMMENT,
COMMENTEND_1,
NORMAL
} parse_remaining_sql_state;
typedef enum {
TYPE_LONG,
TYPE_FLOAT,
TYPE_UNICODE,
TYPE_BUFFER,
TYPE_UNKNOWN
} parameter_type;
pysqlite_Statement *
pysqlite_statement_create(pysqlite_Connection *connection, PyObject *sql)
{
pysqlite_state *state = pysqlite_get_state(NULL);
assert(PyUnicode_Check(sql));
Py_ssize_t size;
const char *sql_cstr = PyUnicode_AsUTF8AndSize(sql, &size);
if (sql_cstr == NULL) {
PyErr_Format(connection->Warning,
"SQL is of wrong type ('%s'). Must be string.",
Py_TYPE(sql)->tp_name);
return NULL;
}
sqlite3 *db = connection->db;
int max_length = sqlite3_limit(db, SQLITE_LIMIT_LENGTH, -1);
if (size >= max_length) {
PyErr_SetString(connection->DataError,
"query string is too large");
return NULL;
}
if (strlen(sql_cstr) != (size_t)size) {
PyErr_SetString(PyExc_ValueError,
"the query contains a null character");
return NULL;
}
sqlite3_stmt *stmt;
const char *tail;
int rc;
Py_BEGIN_ALLOW_THREADS
rc = sqlite3_prepare_v2(db, sql_cstr, (int)size + 1, &stmt, &tail);
Py_END_ALLOW_THREADS
if (rc != SQLITE_OK) {
_pysqlite_seterror(db);
return NULL;
}
if (pysqlite_check_remaining_sql(tail)) {
PyErr_SetString(connection->Warning,
"You can only execute one statement at a time.");
goto error;
}
/* Determine if the statement is a DML statement.
SELECT is the only exception. See #9924. */
int is_dml = 0;
for (const char *p = sql_cstr; *p != 0; p++) {
switch (*p) {
case ' ':
case '\r':
case '\n':
case '\t':
continue;
}
is_dml = (PyOS_strnicmp(p, "insert", 6) == 0)
|| (PyOS_strnicmp(p, "update", 6) == 0)
|| (PyOS_strnicmp(p, "delete", 6) == 0)
|| (PyOS_strnicmp(p, "replace", 7) == 0);
break;
}
pysqlite_Statement *self = PyObject_GC_New(pysqlite_Statement,
state->StatementType);
if (self == NULL) {
goto error;
}
self->st = stmt;
self->in_use = 0;
self->is_dml = is_dml;
self->in_weakreflist = NULL;
PyObject_GC_Track(self);
return self;
error:
(void)sqlite3_finalize(stmt);
return NULL;
}
int pysqlite_statement_bind_parameter(pysqlite_Statement* self, int pos, PyObject* parameter)
{
int rc = SQLITE_OK;
const char *string;
Py_ssize_t buflen;
parameter_type paramtype;
if (parameter == Py_None) {
rc = sqlite3_bind_null(self->st, pos);
goto final;
}
if (PyLong_CheckExact(parameter)) {
paramtype = TYPE_LONG;
} else if (PyFloat_CheckExact(parameter)) {
paramtype = TYPE_FLOAT;
} else if (PyUnicode_CheckExact(parameter)) {
paramtype = TYPE_UNICODE;
} else if (PyLong_Check(parameter)) {
paramtype = TYPE_LONG;
} else if (PyFloat_Check(parameter)) {
paramtype = TYPE_FLOAT;
} else if (PyUnicode_Check(parameter)) {
paramtype = TYPE_UNICODE;
} else if (PyObject_CheckBuffer(parameter)) {
paramtype = TYPE_BUFFER;
} else {
paramtype = TYPE_UNKNOWN;
}
switch (paramtype) {
case TYPE_LONG: {
sqlite_int64 value = _pysqlite_long_as_int64(parameter);
if (value == -1 && PyErr_Occurred())
rc = -1;
else
rc = sqlite3_bind_int64(self->st, pos, value);
break;
}
case TYPE_FLOAT:
rc = sqlite3_bind_double(self->st, pos, PyFloat_AsDouble(parameter));
break;
case TYPE_UNICODE:
string = PyUnicode_AsUTF8AndSize(parameter, &buflen);
if (string == NULL)
return -1;
if (buflen > INT_MAX) {
PyErr_SetString(PyExc_OverflowError,
"string longer than INT_MAX bytes");
return -1;
}
rc = sqlite3_bind_text(self->st, pos, string, (int)buflen, SQLITE_TRANSIENT);
break;
case TYPE_BUFFER: {
Py_buffer view;
if (PyObject_GetBuffer(parameter, &view, PyBUF_SIMPLE) != 0) {
PyErr_SetString(PyExc_ValueError, "could not convert BLOB to buffer");
return -1;
}
if (view.len > INT_MAX) {
PyErr_SetString(PyExc_OverflowError,
"BLOB longer than INT_MAX bytes");
PyBuffer_Release(&view);
return -1;
}
rc = sqlite3_bind_blob(self->st, pos, view.buf, (int)view.len, SQLITE_TRANSIENT);
PyBuffer_Release(&view);
break;
}
case TYPE_UNKNOWN:
rc = -1;
}
final:
return rc;
}
/* returns 0 if the object is one of Python's internal ones that don't need to be adapted */
static int _need_adapt(PyObject* obj)
{
pysqlite_state *state = pysqlite_get_state(NULL);
if (state->BaseTypeAdapted) {
return 1;
}
if (PyLong_CheckExact(obj) || PyFloat_CheckExact(obj)
|| PyUnicode_CheckExact(obj) || PyByteArray_CheckExact(obj)) {
return 0;
} else {
return 1;
}
}
void pysqlite_statement_bind_parameters(pysqlite_Statement* self, PyObject* parameters)
{
pysqlite_state *state = pysqlite_get_state(NULL);
PyObject* current_param;
PyObject* adapted;
const char* binding_name;
int i;
int rc;
int num_params_needed;
Py_ssize_t num_params;
Py_BEGIN_ALLOW_THREADS
num_params_needed = sqlite3_bind_parameter_count(self->st);
Py_END_ALLOW_THREADS
if (PyTuple_CheckExact(parameters) || PyList_CheckExact(parameters) || (!PyDict_Check(parameters) && PySequence_Check(parameters))) {
/* parameters passed as sequence */
if (PyTuple_CheckExact(parameters)) {
num_params = PyTuple_GET_SIZE(parameters);
} else if (PyList_CheckExact(parameters)) {
num_params = PyList_GET_SIZE(parameters);
} else {
num_params = PySequence_Size(parameters);
if (num_params == -1) {
return;
}
}
if (num_params != num_params_needed) {
PyErr_Format(state->ProgrammingError,
"Incorrect number of bindings supplied. The current "
"statement uses %d, and there are %zd supplied.",
num_params_needed, num_params);
return;
}
for (i = 0; i < num_params; i++) {
if (PyTuple_CheckExact(parameters)) {
PyObject *item = PyTuple_GET_ITEM(parameters, i);
current_param = Py_NewRef(item);
} else if (PyList_CheckExact(parameters)) {
PyObject *item = PyList_GetItem(parameters, i);
current_param = Py_XNewRef(item);
} else {
current_param = PySequence_GetItem(parameters, i);
}
if (!current_param) {
return;
}
if (!_need_adapt(current_param)) {
adapted = current_param;
} else {
PyObject *protocol = (PyObject *)state->PrepareProtocolType;
adapted = pysqlite_microprotocols_adapt(current_param,
protocol,
current_param);
Py_DECREF(current_param);
if (!adapted) {
return;
}
}
rc = pysqlite_statement_bind_parameter(self, i + 1, adapted);
Py_DECREF(adapted);
if (rc != SQLITE_OK) {
if (!PyErr_Occurred()) {
PyErr_Format(state->InterfaceError,
"Error binding parameter %d - "
"probably unsupported type.", i);
}
return;
}
}
} else if (PyDict_Check(parameters)) {
/* parameters passed as dictionary */
for (i = 1; i <= num_params_needed; i++) {
PyObject *binding_name_obj;
Py_BEGIN_ALLOW_THREADS
binding_name = sqlite3_bind_parameter_name(self->st, i);
Py_END_ALLOW_THREADS
if (!binding_name) {
PyErr_Format(state->ProgrammingError,
"Binding %d has no name, but you supplied a "
"dictionary (which has only names).", i);
return;
}
binding_name++; /* skip first char (the colon) */
binding_name_obj = PyUnicode_FromString(binding_name);
if (!binding_name_obj) {
return;
}
if (PyDict_CheckExact(parameters)) {
PyObject *item = PyDict_GetItemWithError(parameters, binding_name_obj);
current_param = Py_XNewRef(item);
} else {
current_param = PyObject_GetItem(parameters, binding_name_obj);
}
Py_DECREF(binding_name_obj);
if (!current_param) {
if (!PyErr_Occurred() || PyErr_ExceptionMatches(PyExc_LookupError)) {
PyErr_Format(state->ProgrammingError,
"You did not supply a value for binding "
"parameter :%s.", binding_name);
}
return;
}
if (!_need_adapt(current_param)) {
adapted = current_param;
} else {
PyObject *protocol = (PyObject *)state->PrepareProtocolType;
adapted = pysqlite_microprotocols_adapt(current_param,
protocol,
current_param);
Py_DECREF(current_param);
if (!adapted) {
return;
}
}
rc = pysqlite_statement_bind_parameter(self, i, adapted);
Py_DECREF(adapted);
if (rc != SQLITE_OK) {
if (!PyErr_Occurred()) {
PyErr_Format(state->InterfaceError,
"Error binding parameter :%s - "
"probably unsupported type.", binding_name);
}
return;
}
}
} else {
PyErr_SetString(PyExc_ValueError, "parameters are of unsupported type");
}
}
int pysqlite_statement_finalize(pysqlite_Statement* self)
{
int rc;
rc = SQLITE_OK;
if (self->st) {
Py_BEGIN_ALLOW_THREADS
rc = sqlite3_finalize(self->st);
Py_END_ALLOW_THREADS
self->st = NULL;
}
self->in_use = 0;
return rc;
}
int pysqlite_statement_reset(pysqlite_Statement* self)
{
int rc;
rc = SQLITE_OK;
if (self->in_use && self->st) {
Py_BEGIN_ALLOW_THREADS
rc = sqlite3_reset(self->st);
Py_END_ALLOW_THREADS
if (rc == SQLITE_OK) {
self->in_use = 0;
}
}
return rc;
}
void pysqlite_statement_mark_dirty(pysqlite_Statement* self)
{
self->in_use = 1;
}
static void
stmt_dealloc(pysqlite_Statement *self)
{
PyTypeObject *tp = Py_TYPE(self);
PyObject_GC_UnTrack(self);
if (self->in_weakreflist != NULL) {
PyObject_ClearWeakRefs((PyObject*)self);
}
if (self->st) {
Py_BEGIN_ALLOW_THREADS
sqlite3_finalize(self->st);
Py_END_ALLOW_THREADS
self->st = 0;
}
tp->tp_free(self);
Py_DECREF(tp);
}
static int
stmt_traverse(pysqlite_Statement *self, visitproc visit, void *arg)
{
Py_VISIT(Py_TYPE(self));
return 0;
}
/*
* Checks if there is anything left in an SQL string after SQLite compiled it.
* This is used to check if somebody tried to execute more than one SQL command
* with one execute()/executemany() command, which the DB-API and we don't
* allow.
*
* Returns 1 if there is more left than should be. 0 if ok.
*/
static int pysqlite_check_remaining_sql(const char* tail)
{
const char* pos = tail;
parse_remaining_sql_state state = NORMAL;
for (;;) {
switch (*pos) {
case 0:
return 0;
case '-':
if (state == NORMAL) {
state = LINECOMMENT_1;
} else if (state == LINECOMMENT_1) {
state = IN_LINECOMMENT;
}
break;
case ' ':
case '\t':
break;
case '\n':
case 13:
if (state == IN_LINECOMMENT) {
state = NORMAL;
}
break;
case '/':
if (state == NORMAL) {
state = COMMENTSTART_1;
} else if (state == COMMENTEND_1) {
state = NORMAL;
} else if (state == COMMENTSTART_1) {
return 1;
}
break;
case '*':
if (state == NORMAL) {
return 1;
} else if (state == LINECOMMENT_1) {
return 1;
} else if (state == COMMENTSTART_1) {
state = IN_COMMENT;
} else if (state == IN_COMMENT) {
state = COMMENTEND_1;
}
break;
default:
if (state == COMMENTEND_1) {
state = IN_COMMENT;
} else if (state == IN_LINECOMMENT) {
} else if (state == IN_COMMENT) {
} else {
return 1;
}
}
pos++;
}
return 0;
}
static PyMemberDef stmt_members[] = {
{"__weaklistoffset__", T_PYSSIZET, offsetof(pysqlite_Statement, in_weakreflist), READONLY},
{NULL},
};
static PyType_Slot stmt_slots[] = {
{Py_tp_members, stmt_members},
{Py_tp_dealloc, stmt_dealloc},
{Py_tp_traverse, stmt_traverse},
{0, NULL},
};
static PyType_Spec stmt_spec = {
.name = MODULE_NAME ".Statement",
.basicsize = sizeof(pysqlite_Statement),
.flags = (Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC |
Py_TPFLAGS_IMMUTABLETYPE | Py_TPFLAGS_DISALLOW_INSTANTIATION),
.slots = stmt_slots,
};
int
pysqlite_statement_setup_types(PyObject *module)
{
PyObject *type = PyType_FromModuleAndSpec(module, &stmt_spec, NULL);
if (type == NULL) {
return -1;
}
pysqlite_state *state = pysqlite_get_state(module);
state->StatementType = (PyTypeObject *)type;
return 0;
}