text: /* 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;
  
  int pysqlite_statement_create(pysqlite_Statement* self, pysqlite_Connection* connection, PyObject* sql)
  {
      const char* tail;
      int rc;
      const char* sql_cstr;
      Py_ssize_t sql_cstr_len;
      const char* p;
  
      self->st = NULL;
      self->in_use = 0;
  
      sql_cstr = PyUnicode_AsUTF8AndSize(sql, &sql_cstr_len);
      if (sql_cstr == NULL) {
          rc = PYSQLITE_SQL_WRONG_TYPE;
          return rc;
      }
      if (strlen(sql_cstr) != (size_t)sql_cstr_len) {
          PyErr_SetString(PyExc_ValueError, "the query contains a null character");
          return PYSQLITE_SQL_WRONG_TYPE;
      }
  
      self->in_weakreflist = NULL;
      Py_INCREF(sql);
      self->sql = sql;
  
      /* Determine if the statement is a DML statement.
         SELECT is the only exception. See #9924. */
      self->is_dml = 0;
      for (p = sql_cstr; *p != 0; p++) {
          switch (*p) {
              case ' ':
              case '\r':
              case '\n':
              case '\t':
                  continue;
          }
  
          self->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;
      }
  
      Py_BEGIN_ALLOW_THREADS
      rc = sqlite3_prepare_v2(connection->db,
                              sql_cstr,
                              -1,
                              &self->st,
                              &tail);
      Py_END_ALLOW_THREADS
  
      self->db = connection->db;
  
      if (rc == SQLITE_OK && pysqlite_check_remaining_sql(tail)) {
          (void)sqlite3_finalize(self->st);
          self->st = NULL;
          rc = PYSQLITE_TOO_MUCH_SQL;
      }
  
      return rc;
  }
  
  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)
  {
      if (pysqlite_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)
  {
      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 != num_params_needed) {
              PyErr_Format(pysqlite_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)) {
                  current_param = PyTuple_GET_ITEM(parameters, i);
                  Py_XINCREF(current_param);
              } else if (PyList_CheckExact(parameters)) {
                  current_param = PyList_GET_ITEM(parameters, i);
                  Py_XINCREF(current_param);
              } else {
                  current_param = PySequence_GetItem(parameters, i);
              }
              if (!current_param) {
                  return;
              }
  
              if (!_need_adapt(current_param)) {
                  adapted = current_param;
              } else {
                  adapted = pysqlite_microprotocols_adapt(current_param, (PyObject*)&pysqlite_PrepareProtocolType, NULL);
                  if (adapted) {
                      Py_DECREF(current_param);
                  } else {
                      PyErr_Clear();
                      adapted = current_param;
                  }
              }
  
              rc = pysqlite_statement_bind_parameter(self, i + 1, adapted);
              Py_DECREF(adapted);
  
              if (rc != SQLITE_OK) {
                  if (!PyErr_Occurred()) {
                      PyErr_Format(pysqlite_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++) {
              Py_BEGIN_ALLOW_THREADS
              binding_name = sqlite3_bind_parameter_name(self->st, i);
              Py_END_ALLOW_THREADS
              if (!binding_name) {
                  PyErr_Format(pysqlite_ProgrammingError, "Binding %d has no name, but you supplied a dictionary (which has only names).", i);
                  return;
              }
  
              binding_name++; /* skip first char (the colon) */
              if (PyDict_CheckExact(parameters)) {
                  current_param = PyDict_GetItemString(parameters, binding_name);
                  Py_XINCREF(current_param);
              } else {
                  current_param = PyMapping_GetItemString(parameters, binding_name);
              }
              if (!current_param) {
                  PyErr_Format(pysqlite_ProgrammingError, "You did not supply a value for binding %d.", i);
                  return;
              }
  
              if (!_need_adapt(current_param)) {
                  adapted = current_param;
              } else {
                  adapted = pysqlite_microprotocols_adapt(current_param, (PyObject*)&pysqlite_PrepareProtocolType, NULL);
                  if (adapted) {
                      Py_DECREF(current_param);
                  } else {
                      PyErr_Clear();
                      adapted = current_param;
                  }
              }
  
              rc = pysqlite_statement_bind_parameter(self, i, adapted);
              Py_DECREF(adapted);
  
              if (rc != SQLITE_OK) {
                  if (!PyErr_Occurred()) {
                      PyErr_Format(pysqlite_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;
  }
  
  void pysqlite_statement_dealloc(pysqlite_Statement* self)
  {
      if (self->st) {
          Py_BEGIN_ALLOW_THREADS
          sqlite3_finalize(self->st);
          Py_END_ALLOW_THREADS
      }
  
      self->st = NULL;
  
      Py_XDECREF(self->sql);
  
      if (self->in_weakreflist != NULL) {
          PyObject_ClearWeakRefs((PyObject*)self);
      }
  
      Py_TYPE(self)->tp_free((PyObject*)self);
  }
  
  /*
   * 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;
  }
  
  PyTypeObject pysqlite_StatementType = {
          PyVarObject_HEAD_INIT(NULL, 0)
          MODULE_NAME ".Statement",                       /* tp_name */
          sizeof(pysqlite_Statement),                     /* tp_basicsize */
          0,                                              /* tp_itemsize */
          (destructor)pysqlite_statement_dealloc,         /* tp_dealloc */
          0,                                              /* tp_print */
          0,                                              /* tp_getattr */
          0,                                              /* tp_setattr */
          0,                                              /* tp_reserved */
          0,                                              /* tp_repr */
          0,                                              /* tp_as_number */
          0,                                              /* tp_as_sequence */
          0,                                              /* tp_as_mapping */
          0,                                              /* tp_hash */
          0,                                              /* tp_call */
          0,                                              /* tp_str */
          0,                                              /* tp_getattro */
          0,                                              /* tp_setattro */
          0,                                              /* tp_as_buffer */
          Py_TPFLAGS_DEFAULT,                             /* tp_flags */
          0,                                              /* tp_doc */
          0,                                              /* tp_traverse */
          0,                                              /* tp_clear */
          0,                                              /* tp_richcompare */
          offsetof(pysqlite_Statement, in_weakreflist),   /* tp_weaklistoffset */
          0,                                              /* tp_iter */
          0,                                              /* tp_iternext */
          0,                                              /* tp_methods */
          0,                                              /* tp_members */
          0,                                              /* tp_getset */
          0,                                              /* tp_base */
          0,                                              /* tp_dict */
          0,                                              /* tp_descr_get */
          0,                                              /* tp_descr_set */
          0,                                              /* tp_dictoffset */
          (initproc)0,                                    /* tp_init */
          0,                                              /* tp_alloc */
          0,                                              /* tp_new */
          0                                               /* tp_free */
  };
  
  extern int pysqlite_statement_setup_types(void)
  {
      pysqlite_StatementType.tp_new = PyType_GenericNew;
      return PyType_Ready(&pysqlite_StatementType);
  }
  