Implement exception safe sqlite transaction class (rollback)

3 files changed, 20 insertions, 9 deletions

diff --git a/src/sql/Sql.cpp b/src/sql/Sql.cpp
index 754a30d..4e65ddb 100644
--- a/src/sql/Sql.cpp
+++ b/src/sql/Sql.cpp
@@ -1,5 +1,7 @@
 #include "../../include/odhtdb/sql/Sql.hpp"
 #include <sqlite3.h>
+#include <exception>
+#include <cassert>
 
 namespace odhtdb
 {
@@ -18,4 +20,22 @@ namespace odhtdb
         }
         return SQLITE_OK;
     }
+    
+    SqlTransaction::SqlTransaction(sqlite3 *_db) : 
+        db(_db)
+    {
+        assert(db);
+        sqlite3_exec(db, "BEGIN", 0, 0, 0);
+    }
+    
+    SqlTransaction::~SqlTransaction()
+    {
+        if(std::uncaught_exception())
+            sqlite3_exec(db, "ROLLBACK", 0, 0, 0);
+    }
+    
+    void SqlTransaction::commit()
+    {
+        sqlite3_exec(db, "COMMIT", 0, 0, 0);
+    }
 }
diff --git a/src/sql/SqlExec.cpp b/src/sql/SqlExec.cpp
index 732b2f1..bdb0fbd 100644
--- a/src/sql/SqlExec.cpp
+++ b/src/sql/SqlExec.cpp
@@ -12,7 +12,6 @@ namespace odhtdb
         {
             std::string errMsg = "Failed to prepare sqlite statement, error: ";
             errMsg += sqlite3_errmsg(db);
-            sqlite3_exec(db, "ROLLBACK", 0, 0, 0);
             throw SqlExecException(errMsg);
         }
     }
@@ -37,7 +36,6 @@ namespace odhtdb
             errMsg += " parameters, got ";
             errMsg += std::to_string(args.size());
             errMsg += " arguments";
-            sqlite3_exec(db, "ROLLBACK", 0, 0, 0);
             throw SqlExecException(errMsg);
         }
         
@@ -49,7 +47,6 @@ namespace odhtdb
             {
                 std::string errMsg = "Failed to bind param, error code: ";
                 errMsg += std::to_string(rc);
-                sqlite3_exec(db, "ROLLBACK", 0, 0, 0);
                 throw SqlExecException(errMsg);
             }
             ++paramIndex;
@@ -60,7 +57,6 @@ namespace odhtdb
         {
             std::string errMsg = "Failed to perform sql exec, error: ";
             errMsg += sqlite3_errmsg(db);
-            sqlite3_exec(db, "ROLLBACK", 0, 0, 0);
             throw SqlExecException(errMsg);
         }
     }
diff --git a/src/sql/SqlQuery.cpp b/src/sql/SqlQuery.cpp
index b99f92d..6201332 100644
--- a/src/sql/SqlQuery.cpp
+++ b/src/sql/SqlQuery.cpp
@@ -13,7 +13,6 @@ namespace odhtdb
         {
             std::string errMsg = "Failed to prepare sqlite statement, error: ";
             errMsg += sqlite3_errmsg(db);
-            sqlite3_exec(db, "ROLLBACK", 0, 0, 0);
             throw SqlQueryException(errMsg);
         }
         
@@ -27,7 +26,6 @@ namespace odhtdb
             errMsg += " arguments";
             sqlite3_finalize(stmt);
             stmt = nullptr;
-            sqlite3_exec(db, "ROLLBACK", 0, 0, 0);
             throw SqlQueryException(errMsg);
         }
         
@@ -41,7 +39,6 @@ namespace odhtdb
                 errMsg += std::to_string(rc);
                 sqlite3_finalize(stmt);
                 stmt = nullptr;
-                sqlite3_exec(db, "ROLLBACK", 0, 0, 0);
                 throw SqlQueryException(errMsg);
             }
             ++paramIndex;
@@ -62,7 +59,6 @@ namespace odhtdb
         {
             std::string errMsg = "Failed to perform sql select, error: ";
             errMsg += sqlite3_errmsg(db);
-            sqlite3_exec(db, "ROLLBACK", 0, 0, 0);
             throw SqlQueryException(errMsg);
         }
         
@@ -88,7 +84,6 @@ namespace odhtdb
                 errMsg += " has to be between 0 and ";
                 errMsg += std::to_string(numColumns - 1);
             }
-            sqlite3_exec(db, "ROLLBACK", 0, 0, 0);
             throw SqlQueryException(errMsg);
         }
     }