Reduce peak memory use

Only allow ~1MB of mail data to be buffered by qmailmessagebuffer.

2 files changed, 18 insertions, 1 deletions

diff --git a/src/libraries/qmfmessageserver/qmailmessagebuffer.cpp b/src/libraries/qmfmessageserver/qmailmessagebuffer.cpp
index 61eb5361..1d48f647 100644
--- a/src/libraries/qmfmessageserver/qmailmessagebuffer.cpp
+++ b/src/libraries/qmfmessageserver/qmailmessagebuffer.cpp
@@ -221,8 +221,24 @@ int QMailMessageBuffer::messagePending() {
     return d->waitingForFlush.size();
 }
 
+int QMailMessageBuffer::maximumBufferSize() const
+{
+    // 1MB buffer = 900KB + 100KB for largest message (default 100KB body limit)
+    return 1024*900;
+}
+
 bool QMailMessageBuffer::isFull() {
-    return messagePending() >= d->maxPending;
+    if (messagePending() >= d->maxPending) {
+        return true;
+    }
+    int totalSize = 0;
+    foreach (BufferItem *item, d->waitingForFlush) {
+        totalSize += item->message->body().length();
+        if (totalSize > maximumBufferSize()) {
+            return true;
+        }
+    }
+    return false;
 }
 
 void QMailMessageBuffer::readConfig()
diff --git a/src/libraries/qmfmessageserver/qmailmessagebuffer.h b/src/libraries/qmfmessageserver/qmailmessagebuffer.h
index c9e4bd09..3d556074 100644
--- a/src/libraries/qmfmessageserver/qmailmessagebuffer.h
+++ b/src/libraries/qmfmessageserver/qmailmessagebuffer.h
@@ -72,6 +72,7 @@ public:
     bool addMessage(QMailMessage *message);
     bool updateMessage(QMailMessage *message);
     bool setCallback(QMailMessage *message, QMailMessageBufferFlushCallback *callback);
+    int maximumBufferSize() const;
 
     void flush();