From a16431b3acaeb066f813bfde10c589cd78c0fa12 Mon Sep 17 00:00:00 2001
From: jesus <jesus@lazarus-ide.org>
Date: Sat, 23 May 2015 22:37:52 +0000
Subject: [PATCH] LazReport, fix loading of old binary reports (older than
 version 28), modified patch from Tsvetoslav, issue #27179

git-svn-id: trunk@49154 -
---
 components/lazreport/source/lr_class.pas | 11 +++++----
 components/lazreport/source/lr_utils.pas | 29 ++++++++++++++++++++++++
 2 files changed, 35 insertions(+), 5 deletions(-)

diff --git a/components/lazreport/source/lr_class.pas b/components/lazreport/source/lr_class.pas
index 68e5fd362f..82ee82c838 100644
--- a/components/lazreport/source/lr_class.pas
+++ b/components/lazreport/source/lr_class.pas
@@ -20,7 +20,7 @@ uses
   Dialogs, Menus, Variants, DB, Graphics, Printers, osPrinters, LazUTF8, DOM,
   XMLWrite, XMLRead, XMLConf, LCLType, LCLIntf, TypInfo, LR_View, LR_Pars,
   LR_Intrp, LR_DSet, LR_DBSet, LR_DBRel, LR_Const, DbCtrls, LazUtf8Classes,
-  LazLoggerBase;
+  LCLProc;
 
 const
   lrMaxBandsInReport       = 256; //temp fix. in future need remove this limit
@@ -2727,12 +2727,13 @@ var
   i  : Integer;
 begin
   {$IFDEF DebugLR}
-  DebugLn('%s.TfrView.LoadFromStream begin StreamMode=%d ClassName=%s',
-    [name,Ord(StreamMode),ClassName]);
+  DebugLn('%s.TfrView.LoadFromStream begin StreamMode=%d ClassName=%s Stream.Position=%d',
+    [name,Ord(StreamMode),ClassName, Stream.Position]);
   {$ENDIF}
   with Stream do
   begin
-//    if StreamMode = smDesigning then
+
+    if (frVersion>27) or ((frVersion=27) and lrCanReadName(Stream)) or (StreamMode = smDesigning) then
     begin
       if frVersion >= 23 then
         fName := ReadString(Stream)
@@ -2806,7 +2807,7 @@ begin
 
   end;
   {$IFDEF DebugLR}
-  DebugLn('%s.TfrView.LoadFromStream end',[name]);
+  DebugLn('%s.TfrView.LoadFromStream end Position=%d',[name, Stream.Position]);
   {$ENDIF}
 end;
 
diff --git a/components/lazreport/source/lr_utils.pas b/components/lazreport/source/lr_utils.pas
index ac862cb4c1..390efc3c58 100644
--- a/components/lazreport/source/lr_utils.pas
+++ b/components/lazreport/source/lr_utils.pas
@@ -69,6 +69,7 @@ function lrStrToDateTime(AValue: string): TDateTime;
 function lrExpandVariables(const S:string):string;
 procedure lrNormalizeLocaleFloats(DisableLocale: boolean);
 function lrConfigFolderName(ACreatePath: boolean): string;
+function lrCanReadName(Stream: TStream): boolean;
 
 procedure CanvasTextRectJustify(const Canvas:TCanvas;
   const ARect: TRect; X1, X2, Y: integer; const Text: string;
@@ -923,6 +924,34 @@ begin
     raise EInOutError.Create(SysUtils.Format(lrsUnableToCreateConfigDirectoryS,[Result]));
 end;
 
+function lrCanReadName(Stream: TStream): boolean;
+var
+  oldPosition: Int64;
+  aName: string;
+  n: Integer;
+begin
+  // normally stream is seek-able so this should work....
+  oldPosition := stream.Position;
+  result := false;
+  try
+    try
+      n := stream.ReadWord;
+      setLength(aName, n);
+      stream.Read(aName[1], n);
+      if (n>0) and (stream.ReadByte=0) then begin
+        // unfortunately, objects names are not validated
+        // only check standard names here
+        while (n>0) and (aName[n] in ['a'..'z','A'..'Z','0'..'9','_']) do
+          dec(n);
+        result := (n=0);
+      end;
+    except
+    end;
+  finally
+    Stream.Position := oldPosition;
+  end;
+end;
+
 function UTF8Desc(S: string; var Desc: string): Integer;
 // create Desc as an array with Desc[i] is the size of the UTF-8 codepoint
 var