Eeschema: Add CheckHeader function to SCH_PLUGIN and cycle through plugins when loading files.

eeschema/files-io.cpp

@@ -47,6 +47,7 @@
 #include <project_rescue.h>
 #include <eeschema_config.h>
 #include <sch_legacy_plugin.h>
+#include <sch_eagle_plugin.h>
 
 
 //#define USE_SCH_LEGACY_IO_PLUGIN
@@ -315,30 +316,13 @@ bool SCH_EDIT_FRAME::OpenProjectFiles( const std::vector<wxString>& aFileSet, in
         delete g_RootSheet;   // Delete the current project.
         g_RootSheet = NULL;   // Force CreateScreens() to build new empty project on load failure.
 
-        // Open file and guess at filetype Kicad/Eagle
-        wxTextFile tempFile;
-        tempFile.Open( fullFileName );
-        wxString firstline;
-        // read the first line
-        firstline = tempFile.GetFirstLine();
-        tempFile.Close();
+        SCH_PLUGIN::SCH_PLUGIN_RELEASER pi( SCH_IO_MGR::FindPlugin( SCH_IO_MGR::SCH_LEGACY ) );
 
-        SCH_IO_MGR::SCH_FILE_T filetype;
-
-        if( firstline.StartsWith( "<?xml" ) )
+        // cycle through plugins as they are added to Eeschema
+        if( !pi->CheckHeader( fullFileName ) )
         {
-            filetype = SCH_IO_MGR::SCH_EAGLE;
+            pi.set( SCH_IO_MGR::FindPlugin( SCH_IO_MGR::SCH_EAGLE ) );
         }
-        else if( firstline.StartsWith( "(schematic" ) )
-        {
-            filetype = SCH_IO_MGR::SCH_KICAD;
-        }
-        else
-        {
-            filetype = SCH_IO_MGR::SCH_LEGACY;
-        }
-
-        SCH_PLUGIN::SCH_PLUGIN_RELEASER pi( SCH_IO_MGR::FindPlugin( filetype ) );
 
         try
         {

eeschema/sch_eagle_plugin.cpp

@@ -835,6 +835,21 @@ LIB_TEXT* SCH_EAGLE_PLUGIN::loadSymboltext( LIB_PART* aPart, wxXmlNode* aLibText
 }
 
 
+bool SCH_EAGLE_PLUGIN::CheckHeader( const wxString& aFileName )
+{
+    // Open file and check first line
+    wxTextFile tempFile;
+
+    tempFile.Open( aFileName );
+    wxString firstline;
+    // read the first line
+    firstline = tempFile.GetFirstLine();
+    tempFile.Close();
+
+    return firstline.StartsWith( "<?xml" );
+}
+
+
 void SCH_EAGLE_PLUGIN::Save( const wxString& aFileName, SCH_SCREEN* aSchematic, KIWAY* aKiway,
                              const PROPERTIES* aProperties )
 {

eeschema/sch_eagle_plugin.h

@@ -108,6 +108,7 @@ public:
 
     void SymbolLibOptions( PROPERTIES* aListToAppendTo ) const override;
 
+    bool CheckHeader( const wxString& aFileName ) override; 
 
 private:
     void loadDrawing( wxXmlNode* aDrawingNode );

eeschema/sch_io_mgr.h

@@ -484,6 +484,16 @@ public:
      */
     virtual void SymbolLibOptions( PROPERTIES* aListToAppendTo ) const;
 
+    /**
+     * Function CheckHeader
+     * returns true if the first line in @a aFileName begins with the expected header
+     * system libraries are read only because of where they are installed.)
+     *
+     * @param aFileName is the name of the file to use as input
+     *
+     */
+    virtual bool CheckHeader( const wxString& aFileName );
+
     //-----</PUBLIC SCH_PLUGIN API>------------------------------------------------
 
 

eeschema/sch_legacy_plugin.cpp

@@ -3604,5 +3604,19 @@ void SCH_LEGACY_PLUGIN::SaveLibrary( const wxString& aLibraryPath, const PROPERT
 }
 
 
+bool SCH_LEGACY_PLUGIN::CheckHeader( const wxString& aFileName )
+{
+    // Open file and check first line
+    wxTextFile tempFile;
+
+    tempFile.Open( aFileName );
+    wxString firstline;
+    // read the first line
+    firstline = tempFile.GetFirstLine();
+    tempFile.Close();
+
+    return firstline.StartsWith( "EESchema" );
+}
+
 const char* SCH_LEGACY_PLUGIN::PropBuffering = "buffering";
 const char* SCH_LEGACY_PLUGIN::PropNoDocFile = "no_doc_file";

eeschema/sch_legacy_plugin.h

@@ -124,6 +124,8 @@ public:
                           const PROPERTIES* aProperties = NULL ) override;
     void SaveLibrary( const wxString& aLibraryPath, const PROPERTIES* aProperties = NULL ) override;
 
+    bool CheckHeader(const wxString& aFileName) override;
+
 private:
     void loadHierarchy( SCH_SHEET* aSheet );
     void loadHeader( FILE_LINE_READER& aReader, SCH_SCREEN* aScreen );

eeschema/sch_plugin.cpp

@@ -188,3 +188,11 @@ void SCH_PLUGIN::SymbolLibOptions( PROPERTIES* aListToAppendTo ) const
         ) );
 #endif
 }
+
+
+bool SCH_PLUGIN::CheckHeader( const wxString& aFileName )
+{
+    // not pure virtual so that plugins only have to implement subset of the SCH_PLUGIN interface.
+    not_implemented( this, __FUNCTION__ );
+    return NULL;
+}