mcs/class/IBM.Data.DB2/IBM.Data.DB2/DB2Environment.cs

   1
   2 //
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   4 // a copy of this software and associated documentation files (the
   5 // "Software"), to deal in the Software without restriction, including
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   8 // permit persons to whom the Software is furnished to do so, subject to
   9 // the following conditions:
  10 //
  11 // The above copyright notice and this permission notice shall be
  12 // included in all copies or substantial portions of the Software.
  13 //
  14 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  15 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  16 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  17 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  18 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  19 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  20 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  21 //
  22 using System;\r
  23 using System.Collections;\r
  24 \r
  25 namespace IBM.Data.DB2\r
  26 {\r
  27 \r
  28         internal sealed class DB2Environment : IDisposable\r
  29         {\r
  30                 volatile static DB2Environment environment;
  31                 static readonly object lockobj = new object ();\r
  32                 internal Hashtable connectionPools;\r
  33                 internal IntPtr penvHandle = IntPtr.Zero;\r
  34 \r
  35                 private DB2Environment()\r
  36                 {\r
  37                         connectionPools = Hashtable.Synchronized(new Hashtable());\r
  38 \r
  39                         //                      short sqlRet = DB2CLIWrapper.SQLAllocHandle(DB2Constants.SQL_HANDLE_ENV, IntPtr.Zero, ref penvHandle);\r
  40                         short sqlRet = DB2CLIWrapper.Initialize(ref penvHandle);\r
  41                         DB2ClientUtils.DB2CheckReturn(sqlRet, 0, IntPtr.Zero, "Unable to allocate Environment handle.", null);\r
  42 \r
  43                         // SQLSetEnvAttr( hEnv=0:1, fAttribute=SQL_ATTR_APP_TYPE 2473, vParam=4, cbParam=0 )    // 4=ADO.NET apptype????\r
  44                         // SQLSetEnvAttr( hEnv=0:1, fAttribute=SQL_ATTR_OUTPUT_NTS 10001, vParam=0, cbParam=0 ) // strings not 0-terminated\r
  45                 }\r
  46 \r
  47                 public static DB2Environment Instance\r
  48                 {\r
  49                         get\r
  50                         {\r
  51                                 if(environment == null)\r
  52                                 {\r
  53                                         lock(lockobj)\r
  54                                         {\r
  55                                                 if(environment == null)\r
  56                                                 {\r
  57                                                         environment = new DB2Environment();\r
  58                                                 }\r
  59                                         }\r
  60                                 }\r
  61                                 return environment;\r
  62                         }\r
  63                 }\r
  64                 #region IDisposable Members\r
  65 \r
  66                 bool disposed;\r
  67                 public void Dispose()\r
  68                 {\r
  69                         Dispose(true);\r
  70                         GC.SuppressFinalize(this);\r
  71                 }\r
  72 \r
  73                 public void Dispose(bool disposing)\r
  74                 {\r
  75                         if(disposed)\r
  76                         {\r
  77                                 DB2CLIWrapper.SQLFreeHandle(DB2Constants.SQL_HANDLE_ENV, penvHandle);\r
  78                                 environment = null;\r
  79                         }\r
  80                         disposed = true;\r
  81                 }\r
  82 \r
  83                 ~DB2Environment()\r
  84                 {\r
  85                         Dispose(false);\r
  86                 }\r
  87 \r
  88                 #endregion\r
  89         }\r
  90 \r
  91 }