mcs/class/System.Data/System.Data.Odbc/OdbcConnection.cs

   1 //
   2 // System.Data.Odbc.OdbcConnection
   3 //
   4 // Authors:
   5 //  Brian Ritchie (brianlritchie@hotmail.com)
   6 //
   7 // Copyright (C) Brian Ritchie, 2002
   8 //
   9
  10 //
  11 // Copyright (C) 2004 Novell, Inc (http://www.novell.com)
  12 //
  13 // Permission is hereby granted, free of charge, to any person obtaining
  14 // a copy of this software and associated documentation files (the
  15 // "Software"), to deal in the Software without restriction, including
  16 // without limitation the rights to use, copy, modify, merge, publish,
  17 // distribute, sublicense, and/or sell copies of the Software, and to
  18 // permit persons to whom the Software is furnished to do so, subject to
  19 // the following conditions:
  20 //
  21 // The above copyright notice and this permission notice shall be
  22 // included in all copies or substantial portions of the Software.
  23 //
  24 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  25 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  26 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  27 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  28 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  29 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  30 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  31 //
  32
  33 using System.Collections;
  34 using System.ComponentModel;
  35 using System.Data;
  36 using System.Data.Common;
  37 using System.EnterpriseServices;
  38 using System.Runtime.InteropServices;
  39 using System.Text;
  40 using System.Transactions;
  41
  42 namespace System.Data.Odbc
  43 {
  44         [DefaultEvent ("InfoMessage")]
  45         public sealed class OdbcConnection : DbConnection, ICloneable
  46         {
  47                 #region Fields
  48
  49                 string connectionString;
  50                 int connectionTimeout;
  51                 internal OdbcTransaction transaction;
  52                 IntPtr henv = IntPtr.Zero;
  53                 IntPtr hdbc = IntPtr.Zero;
  54                 bool disposed;
  55                 ArrayList linkedCommands;
  56
  57                 #endregion
  58
  59                 #region Constructors
  60
  61                 public OdbcConnection () : this (String.Empty)
  62                 {
  63                 }
  64
  65                 public OdbcConnection (string connectionString)
  66                 {
  67                         connectionTimeout = 15;
  68                         ConnectionString = connectionString;
  69                 }
  70
  71                 #endregion // Constructors
  72
  73                 #region Properties
  74
  75                 internal IntPtr hDbc {
  76                         get { return hdbc; }
  77                 }
  78
  79                 internal object Generation {
  80                         // We use the linkedCommands array as a generation indicator for statement
  81                         // handles allocated in our subsiduary OdbcCommands.  The rule is that the
  82                         // statement handles are only valid if the generation matches the one
  83                         // returned when the command was linked to the connection.
  84                         get { return linkedCommands; }
  85                 }
  86
  87                 [OdbcCategoryAttribute ("DataCategory_Data")]
  88                 [DefaultValue ("")]
  89                 [OdbcDescriptionAttribute ("Information used to connect to a Data Source")]
  90                 [RefreshPropertiesAttribute (RefreshProperties.All)]
  91                 [EditorAttribute ("Microsoft.VSDesigner.Data.Odbc.Design.OdbcConnectionStringEditor, "+ Consts.AssemblyMicrosoft_VSDesigner, "System.Drawing.Design.UITypeEditor, "+ Consts.AssemblySystem_Drawing )]
  92                 [RecommendedAsConfigurableAttribute (true)]
  93                 public
  94                 override
  95                 string ConnectionString {
  96                         get {
  97                                 if (connectionString == null)
  98                                         return string.Empty;
  99                                 return connectionString;
 100                         }
 101                         set { connectionString = value; }
 102                 }
 103
 104                 [OdbcDescriptionAttribute ("Current connection timeout value, not settable  in the ConnectionString")]
 105                 [DefaultValue (15)]
 106                 [DesignerSerializationVisibility (DesignerSerializationVisibility.Hidden)]
 107                 public
 108                 new
 109                 int ConnectionTimeout {
 110                         get {
 111                                 return connectionTimeout;
 112                         }
 113                         set {
 114                                 if (value < 0)
 115                                         throw new ArgumentException("Timout should not be less than zero.");
 116                                 connectionTimeout = value;
 117                         }
 118                 }
 119
 120                 [DesignerSerializationVisibilityAttribute (DesignerSerializationVisibility.Hidden)]
 121                 [OdbcDescriptionAttribute ("Current data source Catlog value, 'Database=X' in the ConnectionString")]
 122                 public
 123                 override
 124                 string Database {
 125                         get {
 126                                 if (State == ConnectionState.Closed)
 127                                         return string.Empty;
 128                                 return GetInfo (OdbcInfo.DatabaseName);
 129                         }
 130                 }
 131
 132                 [DesignerSerializationVisibilityAttribute (DesignerSerializationVisibility.Hidden)]
 133                 [OdbcDescriptionAttribute ("The ConnectionState indicating whether the connection is open or closed")]
 134                 [BrowsableAttribute (false)]
 135                 public
 136                 override
 137                 ConnectionState State {
 138                         get {
 139                                 if (hdbc != IntPtr.Zero)
 140                                         return ConnectionState.Open;
 141                                 return ConnectionState.Closed;
 142                         }
 143                 }
 144
 145                 [DesignerSerializationVisibilityAttribute (DesignerSerializationVisibility.Hidden)]
 146                 [OdbcDescriptionAttribute ("Current data source, 'Server=X' in the ConnectionString")]
 147                 [Browsable (false)]
 148                 public
 149                 override
 150                 string DataSource {
 151                         get {
 152                                 if (State == ConnectionState.Closed)
 153                                         return string.Empty;
 154                                 return GetInfo (OdbcInfo.DataSourceName);
 155                         }
 156                 }
 157
 158                 [Browsable (false)]
 159                 [DesignerSerializationVisibilityAttribute (DesignerSerializationVisibility.Hidden)]
 160                 [OdbcDescriptionAttribute ("Current ODBC Driver")]
 161                 public string Driver {
 162                         get {
 163                                 if (State == ConnectionState.Closed)
 164                                         return string.Empty;
 165
 166                                 return GetInfo (OdbcInfo.DriverName);
 167                         }
 168                 }
 169
 170                 [DesignerSerializationVisibilityAttribute (DesignerSerializationVisibility.Hidden)]
 171                 [OdbcDescriptionAttribute ("Version of the product accessed by the ODBC Driver")]
 172                 [BrowsableAttribute (false)]
 173                 public
 174                 override
 175                 string ServerVersion {
 176                         get {
 177                                 return GetInfo (OdbcInfo.DbmsVersion);
 178                         }
 179                 }
 180
 181                 internal string SafeDriver {
 182                         get {
 183                                 string driver_name = GetSafeInfo (OdbcInfo.DriverName);
 184                                 if (driver_name == null)
 185                                         return string.Empty;
 186                                 return driver_name;
 187                         }
 188                 }
 189
 190                 #endregion // Properties
 191
 192                 #region Methods
 193
 194                 public
 195                 new
 196                 OdbcTransaction BeginTransaction ()
 197                 {
 198                         return BeginTransaction (IsolationLevel.Unspecified);
 199                 }
 200
 201
 202                 protected override DbTransaction BeginDbTransaction (IsolationLevel isolationLevel)
 203                 {
 204                         return BeginTransaction (isolationLevel);
 205                 }
 206
 207                 public
 208                 new
 209                 OdbcTransaction BeginTransaction (IsolationLevel isolevel)
 210                 {
 211                         if (State == ConnectionState.Closed)
 212                                 throw ExceptionHelper.ConnectionClosed ();
 213
 214                         if (transaction == null) {
 215                                 transaction = new OdbcTransaction (this, isolevel);
 216                                 return transaction;
 217                         } else
 218                                 throw new InvalidOperationException ();
 219                 }
 220
 221
 222                 public
 223                 override
 224                 void Close ()
 225                 {
 226                         OdbcReturn ret = OdbcReturn.Error;
 227                         if (State == ConnectionState.Open) {
 228                                 lock(this) {
 229                                         // close any associated commands
 230                                         // NOTE: we may 'miss' some if the garbage collector has
 231                                         // already started to destroy them.
 232                                         if (linkedCommands != null) {
 233                                                 for (int i = 0; i < linkedCommands.Count; i++) {
 234                                                         WeakReference wr = (WeakReference) linkedCommands [i];
 235                                                         if (wr == null)
 236                                                                 continue;
 237                                                         OdbcCommand c = (OdbcCommand) wr.Target;
 238                                                         if (c != null)
 239                                                                 c.Unlink ();
 240                                                 }
 241                                                 linkedCommands = null;
 242                                         }
 243
 244                                         // disconnect
 245                                         ret = libodbc.SQLDisconnect (hdbc);
 246
 247                                 }
 248                                 // There could be OdbcCommands outstanding (see NOTE above); their
 249                                 // hstmts will have been freed and therefore will be invalid.
 250                                 // However, they will find that their definition of Generation
 251                                 // does not match the connection's, so they won't try and free
 252                                 // those hstmt.
 253                                 if ((ret != OdbcReturn.Success) && (ret != OdbcReturn.SuccessWithInfo))
 254                                         throw CreateOdbcException (OdbcHandleType.Dbc, hdbc);
 255
 256                                 FreeHandles ();
 257                                 transaction = null;
 258                                 RaiseStateChange (ConnectionState.Open, ConnectionState.Closed);
 259                         }
 260                 }
 261
 262                 public
 263                 new
 264                 OdbcCommand CreateCommand ()
 265                 {
 266                         return new OdbcCommand (string.Empty, this, transaction);
 267                 }
 268
 269                 public
 270                 override
 271                 void ChangeDatabase (string value)
 272                 {
 273                         IntPtr ptr = IntPtr.Zero;
 274                         OdbcReturn ret = OdbcReturn.Error;
 275
 276                         try {
 277                                 ptr = Marshal.StringToHGlobalUni (value);
 278                                 ret = libodbc.SQLSetConnectAttr (hdbc, OdbcConnectionAttribute.CurrentCatalog, ptr, value.Length * 2);
 279
 280                                 if (ret != OdbcReturn.Success && ret != OdbcReturn.SuccessWithInfo)
 281                                         throw CreateOdbcException (OdbcHandleType.Dbc, hdbc);
 282                         } finally {
 283                                 if (ptr != IntPtr.Zero)
 284                                         Marshal.FreeCoTaskMem (ptr);
 285                         }
 286                 }
 287
 288                 protected override void Dispose (bool disposing)
 289                 {
 290                         if (!this.disposed) {
 291                                 try {
 292                                         // release the native unmananged resources
 293                                         this.Close ();
 294                                         this.disposed = true;
 295                                 } finally {
 296                                         // call Dispose on the base class
 297                                         base.Dispose (disposing);
 298                                 }
 299                         }
 300                 }
 301
 302                 [MonoTODO]
 303                 object ICloneable.Clone ()
 304                 {
 305                         throw new NotImplementedException ();
 306                 }
 307
 308
 309                 protected override DbCommand CreateDbCommand ()
 310                 {
 311                         return CreateCommand ();
 312                 }
 313
 314                 public
 315                 override
 316                 void Open ()
 317                 {
 318                         if (State == ConnectionState.Open)
 319                                 throw new InvalidOperationException ();
 320
 321                         OdbcReturn ret = OdbcReturn.Error;
 322                         OdbcException e = null;
 323
 324                         try {
 325                                 // allocate Environment handle
 326                                 ret = libodbc.SQLAllocHandle (OdbcHandleType.Env, IntPtr.Zero, ref henv);
 327                                 if ((ret != OdbcReturn.Success) && (ret != OdbcReturn.SuccessWithInfo)) {
 328                                         OdbcErrorCollection errors = new OdbcErrorCollection ();
 329                                         errors.Add (new OdbcError (SafeDriver, "Error in " + SafeDriver, "", 1));
 330                                         e = new OdbcException (errors);
 331                                         MessageHandler (e);
 332                                         throw e;
 333                                 }
 334
 335                                 ret = libodbc.SQLSetEnvAttr (henv, OdbcEnv.OdbcVersion, (IntPtr) libodbc.SQL_OV_ODBC3 , 0);
 336                                 if ((ret != OdbcReturn.Success) && (ret != OdbcReturn.SuccessWithInfo))
 337                                         throw CreateOdbcException (OdbcHandleType.Env, henv);
 338
 339                                 // allocate connection handle
 340                                 ret = libodbc.SQLAllocHandle (OdbcHandleType.Dbc, henv, ref hdbc);
 341                                 if ((ret != OdbcReturn.Success) && (ret != OdbcReturn.SuccessWithInfo))
 342                                         throw CreateOdbcException (OdbcHandleType.Env, henv);
 343
 344                                 // DSN connection
 345                                 if (ConnectionString.ToLower ().IndexOf ("dsn=") >= 0) {
 346                                         string _uid = string.Empty, _pwd = string.Empty, _dsn = string.Empty;
 347                                         string [] items = ConnectionString.Split (new char[1] {';'});
 348                                         foreach (string item in items)
 349                                         {
 350                                                 string [] parts = item.Split (new char[1] {'='});
 351                                                 switch (parts [0].Trim ().ToLower ()) {
 352                                                 case "dsn":
 353                                                         _dsn = parts [1].Trim ();
 354                                                         break;
 355                                                 case "uid":
 356                                                         _uid = parts [1].Trim ();
 357                                                         break;
 358                                                 case "pwd":
 359                                                         _pwd = parts [1].Trim ();
 360                                                         break;
 361                                                 }
 362                                         }
 363                                         ret = libodbc.SQLConnect(hdbc, _dsn, -3, _uid, -3, _pwd, -3);
 364                                         if ((ret != OdbcReturn.Success) && (ret != OdbcReturn.SuccessWithInfo))
 365                                                 throw CreateOdbcException (OdbcHandleType.Dbc, hdbc);
 366                                 } else {
 367                                         // DSN-less Connection
 368                                         string OutConnectionString = new String (' ',1024);
 369                                         short OutLen = 0;
 370                                         ret = libodbc.SQLDriverConnect (hdbc, IntPtr.Zero, ConnectionString, -3,
 371                                                 OutConnectionString, (short) OutConnectionString.Length, ref OutLen, 0);
 372                                         if ((ret != OdbcReturn.Success) && (ret != OdbcReturn.SuccessWithInfo))
 373                                                 throw CreateOdbcException (OdbcHandleType.Dbc, hdbc);
 374                                 }
 375
 376                                 RaiseStateChange (ConnectionState.Closed, ConnectionState.Open);
 377                         } catch {
 378                                 // free handles if any.
 379                                 FreeHandles ();
 380                                 throw;
 381                         }
 382                         disposed = false;
 383                 }
 384
 385                 [MonoTODO]
 386                 public static void ReleaseObjectPool ()
 387                 {
 388                         throw new NotImplementedException ();
 389                 }
 390
 391                 private void FreeHandles ()
 392                 {
 393                         OdbcReturn ret = OdbcReturn.Error;
 394                         if (hdbc != IntPtr.Zero) {
 395                                 ret = libodbc.SQLFreeHandle ((ushort) OdbcHandleType.Dbc, hdbc);
 396                                 if ( (ret != OdbcReturn.Success) && (ret != OdbcReturn.SuccessWithInfo))
 397                                         throw CreateOdbcException (OdbcHandleType.Dbc, hdbc);
 398                         }
 399                         hdbc = IntPtr.Zero;
 400
 401                         if (henv != IntPtr.Zero) {
 402                                 ret = libodbc.SQLFreeHandle ((ushort) OdbcHandleType.Env, henv);
 403                                 if ( (ret != OdbcReturn.Success) && (ret != OdbcReturn.SuccessWithInfo))
 404                                         throw CreateOdbcException (OdbcHandleType.Env, henv);
 405                         }
 406                         henv = IntPtr.Zero;
 407                 }
 408
 409                 public override DataTable GetSchema ()
 410                 {
 411                         if (State == ConnectionState.Closed)
 412                                 throw ExceptionHelper.ConnectionClosed ();
 413                         return MetaDataCollections.Instance;
 414                 }
 415
 416                 public override DataTable GetSchema (string collectionName)
 417                 {
 418                         return GetSchema (collectionName, null);
 419                 }
 420
 421                 public override DataTable GetSchema (string collectionName, string [] restrictionValues)
 422                 {
 423                         if (State == ConnectionState.Closed)
 424                                 throw ExceptionHelper.ConnectionClosed ();
 425                         return GetSchema (collectionName, null);
 426                 }
 427
 428                 [MonoTODO]
 429                 public override void EnlistTransaction (Transaction transaction)
 430                 {
 431                         throw new NotImplementedException ();
 432                 }
 433
 434                 [MonoTODO]
 435                 public void EnlistDistributedTransaction (ITransaction transaction)
 436                 {
 437                         throw new NotImplementedException ();
 438                 }
 439
 440                 internal string GetInfo (OdbcInfo info)
 441                 {
 442                         if (State == ConnectionState.Closed)
 443                                 throw new InvalidOperationException ("The connection is closed.");
 444
 445                         OdbcReturn ret = OdbcReturn.Error;
 446                         short max_length = 512;
 447                         byte [] buffer = new byte [512];
 448                         short actualLength = 0;
 449
 450                         ret = libodbc.SQLGetInfo (hdbc, info, buffer, max_length, ref actualLength);
 451                         if (ret != OdbcReturn.Success && ret != OdbcReturn.SuccessWithInfo)
 452                                 throw CreateOdbcException (OdbcHandleType.Dbc, hdbc);
 453                         return Encoding.Unicode.GetString (buffer, 0, actualLength);
 454                 }
 455
 456                 string GetSafeInfo (OdbcInfo info)
 457                 {
 458                         if (State == ConnectionState.Closed)
 459                                 return null;
 460
 461                         OdbcReturn ret = OdbcReturn.Error;
 462                         short max_length = 512;
 463                         byte [] buffer = new byte [512];
 464                         short actualLength = 0;
 465
 466                         ret = libodbc.SQLGetInfo (hdbc, info, buffer, max_length, ref actualLength);
 467                         if (ret != OdbcReturn.Success && ret != OdbcReturn.SuccessWithInfo)
 468                                 return null;
 469                         return Encoding.Unicode.GetString (buffer, 0, actualLength);
 470                 }
 471
 472                 private void RaiseStateChange (ConnectionState from, ConnectionState to)
 473                 {
 474                         base.OnStateChange (new StateChangeEventArgs (from, to));
 475                 }
 476
 477                 private OdbcInfoMessageEventArgs CreateOdbcInfoMessageEvent (OdbcErrorCollection errors)
 478                 {
 479                         return new OdbcInfoMessageEventArgs (errors);
 480                 }
 481
 482                 private void OnOdbcInfoMessage (OdbcInfoMessageEventArgs e)
 483                 {
 484                         if (InfoMessage != null)
 485                                 InfoMessage (this, e);
 486                 }
 487
 488                 internal OdbcException CreateOdbcException (OdbcHandleType HandleType, IntPtr Handle)
 489                 {
 490                         short buflen = 256;
 491                         short txtlen = 0;
 492                         int nativeerror = 0;
 493                         OdbcReturn ret = OdbcReturn.Success;
 494
 495                         OdbcErrorCollection errors = new OdbcErrorCollection ();
 496
 497                         while (true) {
 498                                 byte [] buf_MsgText = new byte [buflen * 2];
 499                                 byte [] buf_SqlState = new byte [buflen * 2];
 500
 501                                 switch (HandleType) {
 502                                 case OdbcHandleType.Dbc:
 503                                         ret = libodbc.SQLError (IntPtr.Zero, Handle, IntPtr.Zero, buf_SqlState,
 504                                                 ref nativeerror, buf_MsgText, buflen, ref txtlen);
 505                                         break;
 506                                 case OdbcHandleType.Stmt:
 507                                         ret = libodbc.SQLError (IntPtr.Zero, IntPtr.Zero, Handle, buf_SqlState,
 508                                                 ref nativeerror, buf_MsgText, buflen, ref txtlen);
 509                                         break;
 510                                 case OdbcHandleType.Env:
 511                                         ret = libodbc.SQLError (Handle, IntPtr.Zero, IntPtr.Zero, buf_SqlState,
 512                                                 ref nativeerror, buf_MsgText, buflen, ref txtlen);
 513                                         break;
 514                                 }
 515
 516                                 if (ret != OdbcReturn.Success)
 517                                         break;
 518
 519                                 string state = RemoveTrailingNullChar (Encoding.Unicode.GetString (buf_SqlState));
 520                                 string message = Encoding.Unicode.GetString (buf_MsgText, 0, txtlen * 2);
 521
 522                                 errors.Add (new OdbcError (SafeDriver, message, state, nativeerror));
 523                         }
 524
 525                         string source = SafeDriver;
 526                         foreach (OdbcError error in errors)
 527                                 error.SetSource (source);
 528                         return new OdbcException (errors);
 529                 }
 530
 531                 static string RemoveTrailingNullChar (string value)
 532                 {
 533                         return value.TrimEnd ('\0');
 534                 }
 535
 536                 internal object Link (OdbcCommand cmd)
 537                 {
 538                         lock(this) {
 539                                 if (linkedCommands == null)
 540                                         linkedCommands = new ArrayList ();
 541                                 linkedCommands.Add (new WeakReference (cmd));
 542                                 return linkedCommands;
 543                         }
 544                 }
 545
 546                 internal object Unlink (OdbcCommand cmd)
 547                 {
 548                         lock(this) {
 549                                 if (linkedCommands == null)
 550                                         return null;
 551
 552                                 for (int i = 0; i < linkedCommands.Count; i++) {
 553                                         WeakReference wr = (WeakReference) linkedCommands [i];
 554                                         if (wr == null)
 555                                                 continue;
 556                                         OdbcCommand c = (OdbcCommand) wr.Target;
 557                                         if (c == cmd) {
 558                                                 linkedCommands [i] = null;
 559                                                 break;
 560                                         }
 561                                 }
 562                                 return linkedCommands;
 563                         }
 564                 }
 565
 566                 #endregion
 567
 568                 #region Events and Delegates
 569
 570
 571                 [OdbcDescription ("DbConnection_InfoMessage")]
 572                 [OdbcCategory ("DataCategory_InfoMessage")]
 573                 public event OdbcInfoMessageEventHandler InfoMessage;
 574
 575                 private void MessageHandler (OdbcException e)
 576                 {
 577                         OnOdbcInfoMessage (CreateOdbcInfoMessageEvent (e.Errors));
 578                 }
 579
 580                 #endregion
 581         }
 582 }