ADDED: A new IPC API based on protobuf and nng

Details, documentation, and language bindings are works in
progress and will be evolving over the course of KiCad 9
development.

scripting/python_manager.cpp

@@ -0,0 +1,73 @@
+/*
+ * This program source code file is part of KiCad, a free EDA CAD application.
+ *
+ * Copyright (C) 2023 Jon Evans <jon@craftyjon.com>
+ * Copyright (C) 2023 KiCad Developers, see AUTHORS.txt for contributors.
+ *
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or (at your
+ * option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <wx/process.h>
+
+#include <utility>
+
+#include "python_manager.h"
+
+class PYTHON_PROCESS : public wxProcess
+{
+public:
+    PYTHON_PROCESS( std::function<void(int, const wxString&)> aCallback ) :
+            wxProcess(),
+            m_callback( std::move( aCallback ) )
+    {}
+
+    void OnTerminate( int aPid, int aStatus ) override
+    {
+        if( m_callback )
+        {
+            wxString output;
+            wxInputStream* processOut = GetInputStream();
+            size_t bytesRead = 0;
+
+            while( processOut->CanRead() && bytesRead < MAX_OUTPUT_LEN )
+            {
+                char buffer[4096];
+                buffer[ processOut->Read( buffer, sizeof( buffer ) - 1 ).LastRead() ] = '\0';
+                output.append( buffer, sizeof( buffer ) );
+                bytesRead += processOut->LastRead();
+            }
+
+            m_callback( aStatus, output );
+        }
+    }
+
+    static constexpr size_t MAX_OUTPUT_LEN = 1024L * 1024L;
+
+private:
+    std::function<void(int, const wxString&)> m_callback;
+};
+
+
+void PYTHON_MANAGER::Execute( const wxString& aArgs,
+                              const std::function<void( int, const wxString& )>& aCallback )
+{
+    PYTHON_PROCESS* process = new PYTHON_PROCESS( aCallback );
+    process->Redirect();
+
+    wxString cmd = wxString::Format( wxS( "%s %s" ), m_interpreterPath, aArgs );
+    long     pid = wxExecute( cmd, wxEXEC_ASYNC, process );
+
+    if( pid == 0 )
+        aCallback( -1, wxEmptyString );
+}