From 67ccf769c7b46e47e67dafe23790354b8ec146ff Mon Sep 17 00:00:00 2001
From: Maciej Suminski <maciej.suminski@cern.ch>
Date: Fri, 16 Feb 2018 11:59:22 +0100
Subject: [PATCH] Symbol Editor: fix a crash when saving/reverting a library
 not present in sym-lib-table

---
 eeschema/lib_manager.cpp | 20 ++++++++++++++++----
 eeschema/lib_manager.h   |  2 +-
 eeschema/libedit.cpp     |  3 ++-
 3 files changed, 19 insertions(+), 6 deletions(-)

diff --git a/eeschema/lib_manager.cpp b/eeschema/lib_manager.cpp
index 6a5aa1cc1f..e3f9a8a8f3 100644
--- a/eeschema/lib_manager.cpp
+++ b/eeschema/lib_manager.cpp
@@ -73,7 +73,7 @@ int LIB_MANAGER::GetLibraryHash( const wxString& aLibrary ) const
     if( libBufIt != m_libs.end() )
         return libBufIt->second.GetHash();
 
-    auto row = symTable()->FindRow( aLibrary );
+    auto row = GetLibrary( aLibrary );
 
     // return -1 if library does not exist or 0 if not modified
     return row ? std::hash<std::string>{}( aLibrary.ToStdString() + row->GetFullURI( true ).ToStdString() ) : -1;
@@ -91,9 +91,21 @@ wxArrayString LIB_MANAGER::GetLibraryNames() const
 }
 
 
-SYMBOL_LIB_TABLE_ROW* LIB_MANAGER::GetLibrary( const wxString& aLibrary )
+SYMBOL_LIB_TABLE_ROW* LIB_MANAGER::GetLibrary( const wxString& aLibrary ) const
 {
-    return symTable()->FindRow( aLibrary );
+    SYMBOL_LIB_TABLE_ROW* row = nullptr;
+
+    try
+    {
+        row = symTable()->FindRow( aLibrary );
+    }
+    catch( const IO_ERROR& e )
+    {
+        DisplayErrorMessage( &m_frame, wxString::Format( _( "Cannot find library \"%s\" in "
+                "the Symbol Library Table" ), aLibrary ), e.What() );
+    }
+
+    return row;
 }
 
 
@@ -179,7 +191,7 @@ bool LIB_MANAGER::SaveLibrary( const wxString& aLibrary, const wxString& aFileNa
 
         // clear the deleted parts buffer only if data is saved to the original file
         wxFileName original, destination( aFileName );
-        auto row = symTable()->FindRow( aLibrary );
+        auto row = GetLibrary( aLibrary );
 
         if( row )
         {
diff --git a/eeschema/lib_manager.h b/eeschema/lib_manager.h
index c8499721db..7426e6667a 100644
--- a/eeschema/lib_manager.h
+++ b/eeschema/lib_manager.h
@@ -76,7 +76,7 @@ public:
     /**
      * Finds a single library within the (aggregate) library table.
      */
-    SYMBOL_LIB_TABLE_ROW* GetLibrary( const wxString& aLibrary );
+    SYMBOL_LIB_TABLE_ROW* GetLibrary( const wxString& aLibrary ) const;
 
     /**
      * Returns a set containing all part names for a specific library.
diff --git a/eeschema/libedit.cpp b/eeschema/libedit.cpp
index a317952229..39ae033afd 100644
--- a/eeschema/libedit.cpp
+++ b/eeschema/libedit.cpp
@@ -249,7 +249,8 @@ void LIB_EDIT_FRAME::OnSaveAllLibraries( wxCommandEvent& event )
 void LIB_EDIT_FRAME::OnRevertLibrary( wxCommandEvent& aEvent )
 {
     wxString libName = getTargetLib();
-    bool currentLib = ( libName == GetCurLib() );
+    wxString curLib = GetCurLib();
+    bool currentLib = ( libName == curLib || curLib.IsEmpty() );
 
     // Save the current part name/unit to reload after revert
     wxString alias = m_aliasName;