mcs/class/Mono.Data.SqliteClient/Mono.Data.SqliteClient/SqliteDataReader.cs

   1 //
   2 // Mono.Data.SqliteClient.SqliteDataReader.cs
   3 //
   4 // Provides a means of reading a forward-only stream of rows from a Sqlite
   5 // database file.
   6 //
   7 // Author(s): Vladimir Vukicevic  <vladimir@pobox.com>
   8 //            Everaldo Canuto  <everaldo_canuto@yahoo.com.br>
   9 //
  10 // Copyright (C) 2002  Vladimir Vukicevic
  11 //
  12 // Permission is hereby granted, free of charge, to any person obtaining
  13 // a copy of this software and associated documentation files (the
  14 // "Software"), to deal in the Software without restriction, including
  15 // without limitation the rights to use, copy, modify, merge, publish,
  16 // distribute, sublicense, and/or sell copies of the Software, and to
  17 // permit persons to whom the Software is furnished to do so, subject to
  18 // the following conditions:
  19 //
  20 // The above copyright notice and this permission notice shall be
  21 // included in all copies or substantial portions of the Software.
  22 //
  23 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  24 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  25 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  26 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  27 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  28 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  29 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  30 //
  31
  32 using System;
  33 using System.Runtime.InteropServices;
  34 using System.Collections;
  35 using System.Data;
  36 using System.Data.Common;
  37
  38 namespace Mono.Data.SqliteClient
  39 {
  40         public class SqliteDataReader : MarshalByRefObject, IEnumerable, IDataReader, IDisposable, IDataRecord
  41         {
  42
  43                 #region Fields
  44
  45                 private SqliteCommand command;
  46                 private ArrayList rows;
  47                 private ArrayList columns;
  48                 private Hashtable column_names;
  49                 private int current_row;
  50                 private bool closed;
  51                 private bool reading;
  52                 private int records_affected;
  53
  54                 #endregion
  55
  56                 #region Constructors and destructors
  57
  58                 internal SqliteDataReader (SqliteCommand cmd, IntPtr pVm, int version)
  59                 {
  60                         command = cmd;
  61                         rows = new ArrayList ();
  62                         columns = new ArrayList ();
  63                         column_names = new Hashtable ();
  64                         closed = false;
  65                         current_row = -1;
  66                         reading = true;
  67                         ReadpVm (pVm, version);
  68                         ReadingDone ();
  69                 }
  70
  71                 #endregion
  72
  73                 #region Properties
  74
  75                 public int Depth {
  76                         get { return 0; }
  77                 }
  78
  79                 public int FieldCount {
  80                         get { return columns.Count; }
  81                 }
  82
  83                 public object this[string name] {
  84                         get { return ((ArrayList) rows[current_row])[(int) column_names[name]]; }
  85                 }
  86
  87                 public object this[int i] {
  88                         get { return ((ArrayList) rows[current_row])[i]; }
  89                 }
  90
  91                 public bool IsClosed {
  92                         get { return closed; }
  93                 }
  94
  95                 public int RecordsAffected {
  96                         get { return records_affected; }
  97                 }
  98
  99                 #endregion
 100
 101                 #region Internal Methods
 102
 103                 internal void ReadpVm (IntPtr pVm, int version)
 104                 {
 105                         int pN = 0;
 106                         IntPtr pazValue = IntPtr.Zero;
 107                         IntPtr pazColName = IntPtr.Zero;
 108                         SqliteError res;
 109
 110                         while (true) {
 111                                 if (version == 3) {
 112                                         res = Sqlite.sqlite3_step (pVm);
 113                                         pN = Sqlite.sqlite3_column_count (pVm);
 114                                 } else
 115                                         res = Sqlite.sqlite_step (pVm, out pN, out pazValue, out pazColName);
 116                                 if (res == SqliteError.ERROR) {
 117                                         throw new ApplicationException ("Sqlite error");
 118                                 }
 119                                 if (res == SqliteError.DONE) {
 120                                         break;
 121                                 }
 122                                 // We have some data; lets read it
 123                                 if (column_names.Count == 0) {
 124                                         for (int i = 0; i < pN; i++) {
 125                                                 string colName = "";
 126                                                 if (version == 2) {
 127                                                         IntPtr fieldPtr = (IntPtr)Marshal.ReadInt32 (pazColName, i*IntPtr.Size);
 128                                                         colName = Marshal.PtrToStringAnsi (fieldPtr);
 129                                                 } else {
 130                                                         colName = Marshal.PtrToStringAnsi (Sqlite.sqlite3_column_name (pVm, i));
 131                                                 }
 132                                                 columns.Add (colName);
 133                                                 column_names [colName] = i;
 134                                         }
 135                                 }
 136                                 ArrayList data_row = new ArrayList (pN);
 137                                 for (int i = 0; i < pN; i++) {
 138                                         string colData = "";
 139                                         if (version == 2) {
 140                                                 IntPtr fieldPtr = (IntPtr)Marshal.ReadInt32 (pazValue, i*IntPtr.Size);
 141                                                 colData = Marshal.PtrToStringAnsi (fieldPtr);
 142                                                 data_row.Add (Marshal.PtrToStringAnsi (fieldPtr));
 143                                         } else {
 144                                                 switch (Sqlite.sqlite3_column_type (pVm, i)) {
 145                                                         case 1:
 146                                                                 Int64 sqliteint64 = Sqlite.sqlite3_column_int64 (pVm, i);
 147                                                                 data_row.Add (sqliteint64.ToString ());
 148                                                                 break;
 149                                                         case 2:
 150                                                                 double sqlitedouble = Sqlite.sqlite3_column_double (pVm, i);
 151                                                                 data_row.Add (sqlitedouble.ToString ());
 152                                                                 break;
 153                                                         case 3:
 154                                                                 colData = Marshal.PtrToStringAnsi (Sqlite.sqlite3_column_text (pVm, i));
 155                                                                 data_row.Add (colData);
 156                                                                 break;
 157                                                         case 4:
 158                                                                 int blobbytes = Sqlite.sqlite3_column_bytes (pVm, i);
 159                                                                 IntPtr blobptr = Sqlite.sqlite3_column_blob (pVm, i);
 160                                                                 byte[] blob = new byte[blobbytes];
 161                                                                 Marshal.Copy (blobptr, blob, 0, blobbytes);
 162                                                                 data_row.Add (blob);
 163                                                                 break;
 164                                                         case 5:
 165                                                                 data_row.Add (null);
 166                                                                 break;
 167                                                         default:
 168                                                                 throw new ApplicationException ("FATAL: Unknown sqlite3_column_type");
 169                                                 }
 170                                         }
 171                                 }
 172                                 rows.Add (data_row);
 173                         }
 174                 }
 175                 internal void ReadingDone ()
 176                 {
 177                         records_affected = command.NumChanges ();
 178                         reading = false;
 179                 }
 180
 181                 #endregion
 182
 183                 #region  Public Methods
 184
 185                 public void Close ()
 186                 {
 187                         closed = true;
 188                 }
 189
 190                 public void Dispose ()
 191                 {
 192                         Close ();
 193                 }
 194
 195                 IEnumerator IEnumerable.GetEnumerator ()
 196                 {
 197                         return new DbEnumerator (this);
 198                 }
 199
 200                 public DataTable GetSchemaTable ()
 201                 {
 202                         DataTable dataTableSchema = new DataTable ();
 203
 204                         dataTableSchema.Columns.Add ("ColumnName", typeof (String));
 205                         dataTableSchema.Columns.Add ("ColumnOrdinal", typeof (Int32));
 206                         dataTableSchema.Columns.Add ("ColumnSize", typeof (Int32));
 207                         dataTableSchema.Columns.Add ("NumericPrecision", typeof (Int32));
 208                         dataTableSchema.Columns.Add ("NumericScale", typeof (Int32));
 209                         dataTableSchema.Columns.Add ("IsUnique", typeof (Boolean));
 210                         dataTableSchema.Columns.Add ("IsKey", typeof (Boolean));
 211                         dataTableSchema.Columns.Add ("BaseCatalogName", typeof (String));
 212                         dataTableSchema.Columns.Add ("BaseColumnName", typeof (String));
 213                         dataTableSchema.Columns.Add ("BaseSchemaName", typeof (String));
 214                         dataTableSchema.Columns.Add ("BaseTableName", typeof (String));
 215                         dataTableSchema.Columns.Add ("DataType", typeof(Type));
 216                         dataTableSchema.Columns.Add ("AllowDBNull", typeof (Boolean));
 217                         dataTableSchema.Columns.Add ("ProviderType", typeof (Int32));
 218                         dataTableSchema.Columns.Add ("IsAliased", typeof (Boolean));
 219                         dataTableSchema.Columns.Add ("IsExpression", typeof (Boolean));
 220                         dataTableSchema.Columns.Add ("IsIdentity", typeof (Boolean));
 221                         dataTableSchema.Columns.Add ("IsAutoIncrement", typeof (Boolean));
 222                         dataTableSchema.Columns.Add ("IsRowVersion", typeof (Boolean));
 223                         dataTableSchema.Columns.Add ("IsHidden", typeof (Boolean));
 224                         dataTableSchema.Columns.Add ("IsLong", typeof (Boolean));
 225                         dataTableSchema.Columns.Add ("IsReadOnly", typeof (Boolean));
 226
 227                         dataTableSchema.BeginLoadData();
 228                         for (int i = 0; i < this.FieldCount; i += 1 ) {
 229
 230                                 DataRow schemaRow = dataTableSchema.NewRow ();
 231
 232                                 schemaRow["ColumnName"] = columns[i];
 233                                 schemaRow["ColumnOrdinal"] = i;
 234                                 schemaRow["ColumnSize"] = 0;
 235                                 schemaRow["NumericPrecision"] = 0;
 236                                 schemaRow["NumericScale"] = 0;
 237                                 schemaRow["IsUnique"] = false;
 238                                 schemaRow["IsKey"] = false;
 239                                 schemaRow["BaseCatalogName"] = "";
 240                                 schemaRow["BaseColumnName"] = columns[i];
 241                                 schemaRow["BaseSchemaName"] = "";
 242                                 schemaRow["BaseTableName"] = "";
 243                                 schemaRow["DataType"] = typeof(string);
 244                                 schemaRow["AllowDBNull"] = true;
 245                                 schemaRow["ProviderType"] = 0;
 246                                 schemaRow["IsAliased"] = false;
 247                                 schemaRow["IsExpression"] = false;
 248                                 schemaRow["IsIdentity"] = false;
 249                                 schemaRow["IsAutoIncrement"] = false;
 250                                 schemaRow["IsRowVersion"] = false;
 251                                 schemaRow["IsHidden"] = false;
 252                                 schemaRow["IsLong"] = false;
 253                                 schemaRow["IsReadOnly"] = false;
 254
 255                                 dataTableSchema.Rows.Add (schemaRow);
 256                                 schemaRow.AcceptChanges();
 257                         }
 258                         dataTableSchema.EndLoadData();
 259
 260                         return dataTableSchema;
 261                 }
 262
 263                 public bool NextResult ()
 264                 {
 265                         current_row++;
 266
 267                         return (current_row < rows.Count);
 268                 }
 269
 270                 public bool Read ()
 271                 {
 272                         return NextResult ();
 273                 }
 274
 275                 #endregion
 276
 277                 #region IDataRecord getters
 278
 279                 public bool GetBoolean (int i)
 280                 {
 281                         return Convert.ToBoolean ((string) ((ArrayList) rows[current_row])[i]);
 282                 }
 283
 284                 public byte GetByte (int i)
 285                 {
 286                         return Convert.ToByte ((string) ((ArrayList) rows[current_row])[i]);
 287                 }
 288
 289                 public long GetBytes (int i, long fieldOffset, byte[] buffer, int bufferOffset, int length)
 290                 {
 291                         throw new NotImplementedException ();
 292                 }
 293
 294                 public char GetChar (int i)
 295                 {
 296                         return Convert.ToChar ((string) ((ArrayList) rows[current_row])[i]);
 297                 }
 298
 299                 public long GetChars (int i, long fieldOffset, char[] buffer, int bufferOffset, int length)
 300                 {
 301                         throw new NotImplementedException ();
 302                 }
 303
 304                 public IDataReader GetData (int i)
 305                 {
 306                         throw new NotImplementedException ();
 307                 }
 308
 309                 public string GetDataTypeName (int i)
 310                 {
 311                         return "text"; // SQL Lite data type
 312                 }
 313
 314                 public DateTime GetDateTime (int i)
 315                 {
 316                         return Convert.ToDateTime ((string) ((ArrayList) rows[current_row])[i]);
 317                 }
 318
 319                 public decimal GetDecimal (int i)
 320                 {
 321                         return Convert.ToDecimal ((string) ((ArrayList) rows[current_row])[i]);
 322                 }
 323
 324                 public double GetDouble (int i)
 325                 {
 326                         return Convert.ToDouble ((string) ((ArrayList) rows[current_row])[i]);
 327                 }
 328
 329                 public Type GetFieldType (int i)
 330                 {
 331                         return System.Type.GetType ("System.String"); // .NET data type
 332                 }
 333
 334                 public float GetFloat (int i)
 335                 {
 336                         return Convert.ToSingle ((string) ((ArrayList) rows[current_row])[i]);
 337                 }
 338
 339                 public Guid GetGuid (int i)
 340                 {
 341                         throw new NotImplementedException ();
 342                 }
 343
 344                 public short GetInt16 (int i)
 345                 {
 346                         return Convert.ToInt16 ((string) ((ArrayList) rows[current_row])[i]);
 347                 }
 348
 349                 public int GetInt32 (int i)
 350                 {
 351                         return Convert.ToInt32 ((string) ((ArrayList) rows[current_row])[i]);
 352                 }
 353
 354                 public long GetInt64 (int i)
 355                 {
 356                         return Convert.ToInt64 ((string) ((ArrayList) rows[current_row])[i]);
 357                 }
 358
 359                 public string GetName (int i)
 360                 {
 361                         return (string) columns[i];
 362                 }
 363
 364                 public int GetOrdinal (string name)
 365                 {
 366                         return (int) column_names[name];
 367                 }
 368
 369                 public string GetString (int i)
 370                 {
 371                         return ((string) ((ArrayList) rows[current_row])[i]);
 372                 }
 373
 374                 public object GetValue (int i)
 375                 {
 376                         return ((ArrayList) rows[current_row])[i];
 377                 }
 378
 379                 public int GetValues (object[] values)
 380                 {
 381                         int num_to_fill = System.Math.Min (values.Length, columns.Count);
 382                         for (int i = 0; i < num_to_fill; i++) {
 383                                 if (((ArrayList) rows[current_row])[i] != null) {
 384                                         values[i] = ((ArrayList) rows[current_row])[i];
 385                                 } else {
 386                                         values[i] = DBNull.Value;
 387                                 }
 388                         }
 389                         return num_to_fill;
 390                 }
 391
 392                 public bool IsDBNull (int i)
 393                 {
 394                         return (((ArrayList) rows[current_row])[i] == null);
 395                 }
 396
 397                 #endregion
 398         }
 399 }