From be66d708dc1d4edbfa9b3f550b33f2f5f658760b Mon Sep 17 00:00:00 2001
From: Ansgar Becker <anse@heidisql.com>
Date: Wed, 27 Jan 2021 22:41:56 +0100
Subject: [PATCH] Issue #397: simplify synchronized code calls in query
 threads, especially wrt LogFromOutside()

---
 source/apphelpers.pas   | 50 ++++++++---------------------------------
 source/dbconnection.pas | 19 ++++++++++------
 2 files changed, 21 insertions(+), 48 deletions(-)

diff --git a/source/apphelpers.pas b/source/apphelpers.pas
index 9b4490e4..4d8b3c80 100644
--- a/source/apphelpers.pas
+++ b/source/apphelpers.pas
@@ -119,12 +119,6 @@ type
     FRowsAffected: Int64;
     FRowsFound: Int64;
     FWarningCount: Int64;
-    FLogMsg: String;
-    FLogCategory: TDBLogCategory;
-    procedure BeforeQuery;
-    procedure AfterQuery;
-    procedure BatchFinished;
-    procedure Log;
   public
     property Connection: TDBConnection read FConnection;
     property Batch: TSQLBatch read FBatch;
@@ -141,7 +135,7 @@ type
     property ErrorMessage: String read FErrorMessage;
     constructor Create(Connection: TDBConnection; Batch: TSQLBatch; TabNumber: Integer);
     procedure Execute; override;
-    procedure LogFromOutside(Msg: String; Category: TDBLogCategory);
+    procedure LogFromThread(Msg: String; Category: TDBLogCategory);
   end;
 
   TAppSettingDataType = (adInt, adBool, adString);
@@ -2987,15 +2981,15 @@ begin
       end;
       FQueriesInPacket := i - FBatchPosition;
     end;
-    Synchronize(BeforeQuery);
+    Synchronize(procedure begin MainForm.BeforeQueryExecution(Self); end);
     try
       FConnection.LockedByThread := Self;
       DoStoreResult := ResultCount < AppSettings.ReadInt(asMaxQueryResults);
       if (not DoStoreResult) and (not LogMaxResultsDone) then begin
         // Inform user about preference setting for limiting result tabs
-        LogFromOutside(
-          f_('Reached maximum number of result tabs (%d). To display more results, increase setting in Preferences > SQL', [AppSettings.ReadInt(asMaxQueryResults)]),
-          lcInfo);
+        FConnection.Log(lcInfo,
+          f_('Reached maximum number of result tabs (%d). To display more results, increase setting in Preferences > SQL', [AppSettings.ReadInt(asMaxQueryResults)])
+          );
         LogMaxResultsDone := True;
       end;
       FConnection.Query(SQL, DoStoreResult, lcUserFiredSQL);
@@ -3015,46 +3009,20 @@ begin
       end;
     end;
     FConnection.LockedByThread := nil;
-    Synchronize(AfterQuery);
+    Synchronize(procedure begin MainForm.AfterQueryExecution(Self); end);
     // Check if FAborted is set by the main thread, to avoid proceeding the loop in case
     // FStopOnErrors is set to false
     if FAborted or ErrorAborted then
       break;
   end;
 
-  Synchronize(BatchFinished);
+  Synchronize(procedure begin MainForm.FinishedQueryExecution(Self); end);
 end;
 
 
-procedure TQueryThread.BeforeQuery;
+procedure TQueryThread.LogFromThread(Msg: String; Category: TDBLogCategory);
 begin
-  MainForm.BeforeQueryExecution(Self);
-end;
-
-
-procedure TQueryThread.LogFromOutside(Msg: String; Category: TDBLogCategory);
-begin
-  FLogMsg := Msg;
-  FLogCategory := Category;
-  Synchronize(Log);
-end;
-
-
-procedure TQueryThread.Log;
-begin
-  FConnection.OnLog(FLogMsg, FLogCategory, FConnection);
-end;
-
-
-procedure TQueryThread.AfterQuery;
-begin
-  MainForm.AfterQueryExecution(Self);
-end;
-
-
-procedure TQueryThread.BatchFinished;
-begin
-  MainForm.FinishedQueryExecution(Self);
+  Queue(procedure begin FConnection.Log(Category, Msg); end);
 end;
 
 
diff --git a/source/dbconnection.pas b/source/dbconnection.pas
index 8adbcd3c..83821da3 100644
--- a/source/dbconnection.pas
+++ b/source/dbconnection.pas
@@ -4247,16 +4247,21 @@ end;
   If running a thread, log to queue and let the main thread later do logging
 }
 procedure TDBConnection.Log(Category: TDBLogCategory; Msg: String);
+var
+  LogMessage,
 begin
+  // If in a thread, synchronize logging with the main thread. Logging within a thread
+  // causes SynEdit to throw exceptions left and right.
+  if (FLockedByThread <> nil) and (FLockedByThread.ThreadID = GetCurrentThreadID) then begin
+    (FLockedByThread as TQueryThread).LogFromThread(Msg, Category);
+    Exit;
+  end;
+
   if Assigned(FOnLog) then begin
+    LogMessage := Msg;
     if FLogPrefix <> '' then
-      Msg := '['+FLogPrefix+'] ' + Msg;
-    // If in a thread, synchronize logging with the main thread. Logging within a thread
-    // causes SynEdit to throw exceptions left and right.
-    if (FLockedByThread <> nil) and (FLockedByThread.ThreadID = GetCurrentThreadID) then
-      (FLockedByThread as TQueryThread).LogFromOutside(Msg, Category)
-    else
-      FOnLog(Msg, Category, Self);
+      LogMessage := '['+FLogPrefix+'] ' + LogMessage;
+    FOnLog(LogMessage, Category, Self);
   end;
 end;