diff Core/SQLite/Connection.h @ 0:3959d33612cc

initial commit
author Sebastien Jodogne <s.jodogne@gmail.com>
date Thu, 19 Jul 2012 14:32:22 +0200
parents
children db4d996ea264
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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Core/SQLite/Connection.h	Thu Jul 19 14:32:22 2012 +0200
@@ -0,0 +1,159 @@
+/**
+ * Palantir - A Lightweight, RESTful DICOM Store
+ * Copyright (C) 2012 Medical Physics Department, CHU of Liege,
+ * Belgium
+ *
+ * This program is free software: you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ * 
+ * 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. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ **/
+
+
+#pragma once
+
+#include "Statement.h"
+#include "IScalarFunction.h"
+
+#include <string>
+#include <boost/noncopyable.hpp>
+#include <map>
+
+struct sqlite3;
+struct sqlite3_stmt;
+
+#define SQLITE_FROM_HERE SQLite::StatementId(__FILE__, __LINE__)
+
+namespace Palantir
+{
+  namespace SQLite
+  {
+    class Connection : boost::noncopyable
+    {
+      friend class Statement;
+      friend class Transaction;
+
+    private:
+      // All cached statements. Keeping a reference to these statements means that
+      // they'll remain active.
+      typedef std::map<StatementId, StatementReference*>  CachedStatements;
+      CachedStatements cachedStatements_;
+
+      // The actual sqlite database. Will be NULL before Init has been called or if
+      // Init resulted in an error.
+      sqlite3* db_;
+
+      // Number of currently-nested transactions.
+      int transactionNesting_;
+
+      // True if any of the currently nested transactions have been rolled back.
+      // When we get to the outermost transaction, this will determine if we do
+      // a rollback instead of a commit.
+      bool needsRollback_;
+
+      void ClearCache();
+
+      void CheckIsOpen() const;
+
+      sqlite3* GetWrappedObject()
+      {
+        return db_;
+      }
+
+      StatementReference& GetCachedStatement(const StatementId& id,
+                                             const char* sql);
+
+      bool DoesTableOrIndexExist(const char* name, 
+                                 const char* type) const;
+
+      void DoRollback();
+
+    public:
+      // The database is opened by calling Open[InMemory](). Any uncommitted
+      // transactions will be rolled back when this object is deleted.
+      Connection();
+      ~Connection();
+
+      void Open(const std::string& path);
+
+      void OpenInMemory();
+
+      void Close();
+
+      bool Execute(const char* sql);
+
+      bool Execute(const std::string& sql)
+      {
+        return Execute(sql.c_str());
+      }
+
+      IScalarFunction* Register(IScalarFunction* func);  // Takes the ownership of the function
+
+      // Info querying -------------------------------------------------------------
+
+      // Used to check a |sql| statement for syntactic validity. If the
+      // statement is valid SQL, returns true.
+      bool IsSQLValid(const char* sql);
+
+      // Returns true if the given table exists.
+      bool DoesTableExist(const char* table_name) const;
+
+      // Returns true if the given index exists.
+      bool DoesIndexExist(const char* index_name) const;
+    
+      // Returns true if a column with the given name exists in the given table.
+      bool DoesColumnExist(const char* table_name, const char* column_name) const;
+
+      // Returns sqlite's internal ID for the last inserted row. Valid only
+      // immediately after an insert.
+      int64_t GetLastInsertRowId() const;
+
+      // Returns sqlite's count of the number of rows modified by the last
+      // statement executed. Will be 0 if no statement has executed or the database
+      // is closed.
+      int GetLastChangeCount() const;
+
+      // Errors --------------------------------------------------------------------
+
+      // Returns the error code associated with the last sqlite operation.
+      int GetErrorCode() const;
+
+      // Returns the errno associated with GetErrorCode().  See
+      // SQLITE_LAST_ERRNO in SQLite documentation.
+      int GetLastErrno() const;
+
+      // Returns a pointer to a statically allocated string associated with the
+      // last sqlite operation.
+      const char* GetErrorMessage() const;
+
+
+      // Diagnostics (for unit tests) ----------------------------------------------
+
+      int ExecuteAndReturnErrorCode(const char* sql);
+    
+      bool HasCachedStatement(const StatementId& id) const
+      {
+        return cachedStatements_.find(id) != cachedStatements_.end();
+      }
+
+      int GetTransactionNesting() const
+      {
+        return transactionNesting_;
+      }
+
+      // Transactions --------------------------------------------------------------
+
+      bool BeginTransaction();
+      void RollbackTransaction();
+      bool CommitTransaction();
+    };
+  }
+}