From 6c30e4f90b8fb1d5ef38629a051106bb6f5e13c0 Mon Sep 17 00:00:00 2001
From: jean-pierre charras <jp.charras@wanadoo.fr>
Date: Mon, 28 Apr 2025 17:39:53 +0200
Subject: [PATCH] Gerbview: fix a maximum number (50) of Error messages in
 report list.

Having a lot of errors can happen when trying to open a non gerber files
(this is easy when loading a zip archive).
With a *lot* of errors (if a large .step file is found) Gerbview can hang.

Fixes https://gitlab.com/kicad/code/kicad/-/issues/20799

(cherry picked from commit d5cf54197468a825ba8cf09b46d228d9f425f7d1)
---
 gerbview/gerber_file_image.cpp | 14 ++++++++++++++
 gerbview/gerber_file_image.h   |  5 +----
 gerbview/readgerb.cpp          |  2 +-
 3 files changed, 16 insertions(+), 5 deletions(-)

diff --git a/gerbview/gerber_file_image.cpp b/gerbview/gerber_file_image.cpp
index a5e6b1be0d..020544da91 100644
--- a/gerbview/gerber_file_image.cpp
+++ b/gerbview/gerber_file_image.cpp
@@ -112,6 +112,20 @@ GERBER_FILE_IMAGE::~GERBER_FILE_IMAGE()
 }
 
 
+void GERBER_FILE_IMAGE::AddMessageToList( const wxString& aMessage )
+{
+    /* Add a message to the message list, but only if there are less than max_messages
+     * to avoid very long list (can happens if trying to read a non gerber file)
+     */
+    const int max_messages = 50;    // Arbitrary but reasonable value.
+
+    if( m_messagesList.size() < max_messages )
+        m_messagesList.Add( aMessage );
+    else if( m_messagesList.size() == max_messages )
+        m_messagesList.Add( _( "Too many messages, some are skipped" ) );
+}
+
+
 void GERBER_FILE_IMAGE::SetDrawOffetAndRotation( VECTOR2D aOffsetMM, EDA_ANGLE aRotation )
 {
     m_DisplayOffset.x = KiROUND( aOffsetMM.x * gerbIUScale.IU_PER_MM );
diff --git a/gerbview/gerber_file_image.h b/gerbview/gerber_file_image.h
index 3e87fbdfe1..0c86ff0867 100644
--- a/gerbview/gerber_file_image.h
+++ b/gerbview/gerber_file_image.h
@@ -212,10 +212,7 @@ public:
     /**
      * Add a message to the message list
      */
-    void AddMessageToList( const wxString& aMessage )
-    {
-        m_messagesList.Add( aMessage );
-    }
+    void AddMessageToList( const wxString& aMessage );
 
     /**
      * Return the current coordinate type pointed to by XnnYnn Text (XnnnnYmmmm).
diff --git a/gerbview/readgerb.cpp b/gerbview/readgerb.cpp
index dc8c05026f..f44f2a0537 100644
--- a/gerbview/readgerb.cpp
+++ b/gerbview/readgerb.cpp
@@ -323,7 +323,7 @@ bool GERBER_FILE_IMAGE::LoadGerberFile( const wxString& aFullFileName )
                 break;
 
             default:
-                msg.Printf( wxT( "Unexpected char 0x%2.2X" ), *text );
+                msg.Printf( wxT( "Unexpected char 0x%2.2X (%c)" ), *text, *text );
                 AddMessageToList( msg );
                 text++;
                 break;