From 4385c6bae1a66aa94beb703dcc16e12bdf0ebb0e Mon Sep 17 00:00:00 2001
From: Christian Mollekopf <chrigi_1@fastmail.fm>
Date: Thu, 13 Aug 2015 22:43:36 +0200
Subject: Autocommit for the transaction

---
 common/storage.h        |  2 ++
 common/storage_lmdb.cpp | 44 ++++++++++++++++++++++++++++++++++++++++----
 2 files changed, 42 insertions(+), 4 deletions(-)

(limited to 'common')

diff --git a/common/storage.h b/common/storage.h
index 9fe4e99..da225ef 100644
--- a/common/storage.h
+++ b/common/storage.h
@@ -59,6 +59,8 @@ public:
         bool commit(const std::function<void(const Storage::Error &error)> &errorHandler = std::function<void(const Storage::Error &error)>());
         void abort();
 
+        void setAutocommit(int interval);
+
         /**
          * Write a value
          */
diff --git a/common/storage_lmdb.cpp b/common/storage_lmdb.cpp
index 983d0e2..86d76a0 100644
--- a/common/storage_lmdb.cpp
+++ b/common/storage_lmdb.cpp
@@ -52,14 +52,17 @@ int getErrorCode(int e)
 class Storage::Transaction::Private
 {
 public:
-    Private(MDB_txn *_txn, MDB_dbi _dbi, bool _allowDuplicates, const std::function<void(const Storage::Error &error)> &_defaultErrorHandler, const QString &_name)
-        : transaction(_txn),
+    Private(MDB_txn *_txn, MDB_dbi _dbi, bool _allowDuplicates, const std::function<void(const Storage::Error &error)> &_defaultErrorHandler, const QString &_name, MDB_env *_env)
+        : env(_env),
+        transaction(_txn),
         dbi(_dbi),
         allowDuplicates(_allowDuplicates),
         defaultErrorHandler(_defaultErrorHandler),
         name(_name),
         implicitCommit(false),
-        error(false)
+        error(false),
+        autoCommitInterval(0),
+        modificationCounter(0)
     {
 
     }
@@ -68,6 +71,7 @@ public:
 
     }
 
+    MDB_env *env;
     MDB_txn *transaction;
     MDB_dbi dbi;
     bool allowDuplicates;
@@ -75,6 +79,8 @@ public:
     QString name;
     bool implicitCommit;
     bool error;
+    int autoCommitInterval;
+    int modificationCounter;
 };
 
 Storage::Transaction::Transaction()
@@ -128,6 +134,13 @@ void Storage::Transaction::abort()
     d->transaction = nullptr;
 }
 
+void Storage::Transaction::setAutocommit(int interval)
+{
+    if (d) {
+        d->autoCommitInterval = interval;
+    }
+}
+
 bool Storage::Transaction::write(const QByteArray &sKey, const QByteArray &sValue, const std::function<void(const Storage::Error &error)> &errorHandler)
 {
     if (!d || !d->transaction) {
@@ -160,6 +173,29 @@ bool Storage::Transaction::write(const QByteArray &sKey, const QByteArray &sValu
         d->implicitCommit = true;
     }
 
+    if (d->autoCommitInterval > 0) {
+        d->modificationCounter++;
+        if (d->modificationCounter >= d->autoCommitInterval) {
+            commit();
+
+            MDB_txn *txn;
+            rc = mdb_txn_begin(d->env, NULL, 0, &txn);
+            if (!rc) {
+                //TODO: Move opening of dbi into Transaction for different named databases
+                MDB_dbi dbi;
+                rc = mdb_dbi_open(txn, NULL, d->allowDuplicates ? MDB_DUPSORT : 0, &dbi);
+                if (rc) {
+                    errorHandler(Error(d->name.toLatin1(), ErrorCodes::GenericError, "Error while opening transaction: " + QByteArray(mdb_strerror(rc))));
+                } else {
+                    d->transaction = txn;
+                    d->dbi = dbi;
+                }
+            }
+
+            d->modificationCounter = 0;
+        }
+    }
+
     return !rc;
 }
 
@@ -387,7 +423,7 @@ Storage::Transaction Storage::createTransaction(AccessMode type, const std::func
             errorHandler(Error(d->name.toLatin1(), ErrorCodes::GenericError, "Error while opening transaction: " + QByteArray(mdb_strerror(rc))));
             return Transaction();
         }
-        return Transaction(new Transaction::Private(txn, dbi, d->allowDuplicates, defaultErrorHandler(), d->name));
+        return Transaction(new Transaction::Private(txn, dbi, d->allowDuplicates, defaultErrorHandler(), d->name, d->env));
     } else {
         if (rc) {
             errorHandler(Error(d->name.toLatin1(), ErrorCodes::GenericError, "Error while beginning transaction: " + QByteArray(mdb_strerror(rc))));
-- 
cgit v1.2.3