From d44e55451f9303da93d2f5ac29a3f7c1b58dfdc6 Mon Sep 17 00:00:00 2001
From: Ansgar Becker <ansgarbecker@users.noreply.github.com>
Date: Mon, 26 Dec 2011 22:40:32 +0000
Subject: [PATCH] Creating an ADO handle throws exception if MDAC is missing,
 especially on Wine. Create that handle in TAdoDBConnection.SetActive, not in
 TAdoDBConnection.Create, and turn the exception into an EDatabaseError, so
 the caller gets a handled error. Additionally, display a possible solution in
 that error popup, which I found on
 http://forum.winehq.org/viewtopic.php?p=30653 . Fixes issue #2660.

---
 source/dbconnection.pas | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/source/dbconnection.pas b/source/dbconnection.pas
index a68fb57a..ed94a4c9 100644
--- a/source/dbconnection.pas
+++ b/source/dbconnection.pas
@@ -747,7 +747,6 @@ var
   i: Integer;
 begin
   inherited;
-  FAdoHandle := TAdoConnection.Create(AOwner);
   FQuoteChar := '"';
   SetLength(FDatatypes, Length(MSSQLDatatypes));
   for i:=0 to High(MSSQLDatatypes) do
@@ -997,6 +996,19 @@ var
 begin
   if Value then begin
     DoBeforeConnect;
+    try
+      // Creating the ADO object throws exceptions if MDAC is missing, especially on Wine
+      FAdoHandle := TAdoConnection.Create(Owner);
+    except
+      on E:Exception do begin
+        if Pos('Data Access Components', E.Message) > 0 then
+          raise EDatabaseError.Create(E.Message+CRLF+CRLF+
+            'On Wine, you can try to install these:'+CRLF+
+            'sh winetricks mdac28')
+        else
+          raise;
+      end;
+    end;
     NetLib := '';
     case Parameters.NetType of
       ntMSSQL_NamedPipe: NetLib := 'DBNMPNTW';