[TD-2598] feature: C# taosdemo. add TDengineDriver.cs

tests/examples/C#/taosdemo/TDengineDriver.cs

+/*
+ * Copyright (c) 2019 TAOS Data, Inc. <jhtao@taosdata.com>
+ *
+ * This program is free software: you can use, redistribute, and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3
+ * or later ("AGPL"), as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+using System;
+using System.Collections.Generic;
+using System.Runtime.InteropServices;
+
+namespace TDengineDriver
+{
+    enum TDengineDataType
+    {
+        TSDB_DATA_TYPE_NULL = 0,     // 1 bytes
+        TSDB_DATA_TYPE_BOOL = 1,     // 1 bytes
+        TSDB_DATA_TYPE_TINYINT = 2,  // 1 bytes
+        TSDB_DATA_TYPE_SMALLINT = 3, // 2 bytes
+        TSDB_DATA_TYPE_INT = 4,      // 4 bytes
+        TSDB_DATA_TYPE_BIGINT = 5,   // 8 bytes
+        TSDB_DATA_TYPE_FLOAT = 6,    // 4 bytes
+        TSDB_DATA_TYPE_DOUBLE = 7,   // 8 bytes
+        TSDB_DATA_TYPE_BINARY = 8,   // string
+        TSDB_DATA_TYPE_TIMESTAMP = 9,// 8 bytes
+        TSDB_DATA_TYPE_NCHAR = 10    // unicode string
+    }
+
+    enum TDengineInitOption
+    {
+        TSDB_OPTION_LOCALE = 0,
+        TSDB_OPTION_CHARSET = 1,
+        TSDB_OPTION_TIMEZONE = 2,
+        TDDB_OPTION_CONFIGDIR = 3,
+        TDDB_OPTION_SHELL_ACTIVITY_TIMER = 4
+    }
+
+    class TDengineMeta
+    {
+        public string name;
+        public short size;
+        public byte type;
+        public string TypeName()
+        {
+            switch ((TDengineDataType)type)
+            {
+                case TDengineDataType.TSDB_DATA_TYPE_BOOL:
+                    return "BOOLEAN";
+                case TDengineDataType.TSDB_DATA_TYPE_TINYINT:
+                    return "BYTE";
+                case TDengineDataType.TSDB_DATA_TYPE_SMALLINT:
+                    return "SHORT";
+                case TDengineDataType.TSDB_DATA_TYPE_INT:
+                    return "INT";
+                case TDengineDataType.TSDB_DATA_TYPE_BIGINT:
+                    return "LONG";
+                case TDengineDataType.TSDB_DATA_TYPE_FLOAT:
+                    return "FLOAT";
+                case TDengineDataType.TSDB_DATA_TYPE_DOUBLE:
+                    return "DOUBLE";
+                case TDengineDataType.TSDB_DATA_TYPE_BINARY:
+                    return "STRING";
+                case TDengineDataType.TSDB_DATA_TYPE_TIMESTAMP:
+                    return "TIMESTAMP";
+                case TDengineDataType.TSDB_DATA_TYPE_NCHAR:
+                    return "NCHAR";
+                default:
+                    return "undefine";
+            }
+        }
+    }
+
+    class TDengine
+    {
+        public const int TSDB_CODE_SUCCESS = 0;
+
+        [DllImport("taos", EntryPoint = "taos_init", CallingConvention = CallingConvention.Cdecl)]
+        static extern public void Init();
+
+        [DllImport("taos", EntryPoint = "taos_cleanup", CallingConvention = CallingConvention.Cdecl)]
+        static extern public void Cleanup();
+
+        [DllImport("taos", EntryPoint = "taos_options", CallingConvention = CallingConvention.Cdecl)]
+        static extern public void Options(int option, string value);
+
+        [DllImport("taos", EntryPoint = "taos_connect", CallingConvention = CallingConvention.Cdecl)]
+        static extern public IntPtr Connect(string ip, string user, string password, string db, short port);
+
+        [DllImport("taos", EntryPoint = "taos_errstr", CallingConvention = CallingConvention.Cdecl)]
+        static extern private IntPtr taos_errstr(IntPtr res);
+        static public string Error(IntPtr res)
+        {
+            IntPtr errPtr = taos_errstr(res);
+            return Marshal.PtrToStringAnsi(errPtr);
+        }
+
+        [DllImport("taos", EntryPoint = "taos_errno", CallingConvention = CallingConvention.Cdecl)]
+        static extern public int ErrorNo(IntPtr res);
+
+        [DllImport("taos", EntryPoint = "taos_query", CallingConvention = CallingConvention.Cdecl)]
+        static extern public IntPtr Query(IntPtr conn, string sqlstr);
+
+        [DllImport("taos", EntryPoint = "taos_affected_rows", CallingConvention = CallingConvention.Cdecl)]
+        static extern public int AffectRows(IntPtr res);
+
+        [DllImport("taos", EntryPoint = "taos_field_count", CallingConvention = CallingConvention.Cdecl)]
+        static extern public int FieldCount(IntPtr res);
+
+        [DllImport("taos", EntryPoint = "taos_fetch_fields", CallingConvention = CallingConvention.Cdecl)]
+        static extern private IntPtr taos_fetch_fields(IntPtr res);
+        static public List<TDengineMeta> FetchFields(IntPtr res)
+        {
+            const int fieldSize = 68;
+
+            List<TDengineMeta> metas = new List<TDengineMeta>();
+            if (res == IntPtr.Zero)
+            {
+                return metas;
+            }
+
+            int fieldCount = FieldCount(res);
+            IntPtr fieldsPtr = taos_fetch_fields(res);
+
+            for (int i = 0; i < fieldCount; ++i)
+            {
+                int offset = i * fieldSize;
+
+                TDengineMeta meta = new TDengineMeta();
+                meta.name = Marshal.PtrToStringAnsi(fieldsPtr + offset);
+                meta.type = Marshal.ReadByte(fieldsPtr + offset + 65);
+                meta.size = Marshal.ReadInt16(fieldsPtr + offset + 66);
+                metas.Add(meta);
+            }
+
+            return metas;
+        }
+
+        [DllImport("taos", EntryPoint = "taos_fetch_row", CallingConvention = CallingConvention.Cdecl)]
+        static extern public IntPtr FetchRows(IntPtr res);
+
+        [DllImport("taos", EntryPoint = "taos_free_result", CallingConvention = CallingConvention.Cdecl)]
+        static extern public IntPtr FreeResult(IntPtr res);
+
+        [DllImport("taos", EntryPoint = "taos_close", CallingConvention = CallingConvention.Cdecl)]
+        static extern public int Close(IntPtr taos);
+    }
+}