update Find_file_in_fileselector() to return -1 when not found

src/buttons.c

@@ -1314,7 +1314,8 @@ void Button_Skins(int btn)
   Sort_list_of_files(&Font_files_list);
 
   selected_font = Find_file_in_fileselector(&Font_files_list, Config.Font_file);
-
+  if (selected_font < 0)
+    selected_font = 0;
 
   // --------------------------------------------------------------
 
@@ -1340,6 +1341,8 @@ void Button_Skins(int btn)
     Draw_one_skin_name, 2); // 4
 
   skin_list->Cursor_position = Find_file_in_fileselector(&Skin_files_list, Config.Skin_file);
+  if (skin_list->Cursor_position < 0)
+    skin_list->Cursor_position = 0;
 
   // Buttons to choose a font
   font_dropdown = Window_set_dropdown_button(172, 43, 104, 11, 0, Get_item_by_index(&Font_files_list,selected_font)->Short_name,1,0,1,RIGHT_SIDE|LEFT_SIDE,0); // 5

src/factory.c

@@ -2309,6 +2309,8 @@ void Highlight_script(T_Fileselector *selector, T_List_button *list, const char
   short index;
 
   index=Find_file_in_fileselector(selector, selected_file);
+  if (index < 0)
+    index = 0;  // 1st item if selected_file is not found
   Locate_list_item(list, index);
 }
 

src/filesel.c

@@ -1386,13 +1386,13 @@ short Find_file_in_fileselector(T_Fileselector *list, const char * fname)
 {
   T_Fileselector_item * item;
   short  index;
-  short  close_match=0;
+  short  close_match = -1;
 
   index=0;
   for (item=list->First; item!=NULL; item=item->Next)
   {
     if (strcmp(item->Full_name,fname)==0)
-      return index;
+      return index; // exact match
     if (strcasecmp(item->Full_name,fname)==0)
       close_match=index;
       
@@ -1402,7 +1402,10 @@ short Find_file_in_fileselector(T_Fileselector *list, const char * fname)
   return close_match;
 }
 
-void Highlight_file(short index)
+/// Set the position and index of the file list according
+/// to the selected index
+/// @param index index of selected file
+static void Highlight_file(short index)
 {
 
   if ((Filelist.Nb_elements<=10) || (index<5))
@@ -1685,7 +1688,8 @@ byte Button_Load_or_Save(T_Selector_settings *settings, byte load, T_IO_Context
 
   if (!load)
   {
-    Highlight_file(Find_file_in_fileselector(&Filelist, context->File_name));
+    short pos = Find_file_in_fileselector(&Filelist, context->File_name);
+    Highlight_file((pos >= 0) ? pos : 0);
     Prepare_and_display_filelist(Selector->Position,Selector->Offset,file_scroller);
 
     // On initialise le nom de fichier à celui en cours et non pas celui sous
@@ -1885,15 +1889,15 @@ byte Button_Load_or_Save(T_Selector_settings *settings, byte load, T_IO_Context
           if (savename != NULL)
           {
             // attempt to find the file name in new list
-            int pos=Find_file_in_fileselector(&Filelist, savename);
-            if (pos!=0)
+            short pos=Find_file_in_fileselector(&Filelist, savename);
+            if (pos >= 0)
             {
               Highlight_file(pos);
               Prepare_and_display_filelist(Selector->Position,Selector->Offset,file_scroller);
             }
             // If the file is (still present) or it's a name with new
             // extension, set it as the proposed file name.
-            if (pos!=0 || !load)
+            if (pos >= 0 || !load)
             {
               strcpy(Selector_filename, savename);
               memcpy(Selector_filename_unicode, Selector_filename_unicode_save, sizeof(Selector_filename_unicode_save));
@@ -2265,7 +2269,8 @@ byte Button_Load_or_Save(T_Selector_settings *settings, byte load, T_IO_Context
           Read_list_of_files(&Filelist, Selector->Format_filter);
           Sort_list_of_files(&Filelist);
           // Set the fileselector bar on the directory we're coming from
-          Highlight_file(Find_file_in_fileselector(&Filelist, previous_directory));
+          pos = Find_file_in_fileselector(&Filelist, previous_directory);
+          Highlight_file((pos >= 0) ? pos : 0);
           // display the 1st visible files
           Prepare_and_display_filelist(Selector->Position,Selector->Offset,file_scroller);
           Display_cursor();

src/filesel.h

@@ -72,6 +72,11 @@ T_Fileselector_item * Get_item_by_index(T_Fileselector *list, unsigned short ind
 
 void Read_list_of_drives(T_Fileselector *list, byte name_length);
 
+/// Look for a file name in a file selector list
+/// @param list  The file selector list
+/// @param fname The file name to search for
+/// @return the index of the file
+/// @return -1 if the file name was not found
 short Find_file_in_fileselector(T_Fileselector *list, const char * fname);
 
 void Locate_list_item(T_List_button * list, short selected_item);