1. change some directory structure for the build script

2. add build script and document
   see DOC/BuildVentoyFromSource.txt for detail

GRUB2/MOD_SRC/grub-2.04/grub-core/gfxmenu/gfxmenu.c

+/* gfxmenu.c - Graphical menu interface controller. */
+/*
+ *  GRUB  --  GRand Unified Bootloader
+ *  Copyright (C) 2008  Free Software Foundation, Inc.
+ *
+ *  GRUB 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.
+ *
+ *  GRUB 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 GRUB.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <grub/types.h>
+#include <grub/misc.h>
+#include <grub/mm.h>
+#include <grub/err.h>
+#include <grub/dl.h>
+#include <grub/command.h>
+#include <grub/video.h>
+#include <grub/gfxterm.h>
+#include <grub/bitmap.h>
+#include <grub/bitmap_scale.h>
+#include <grub/term.h>
+#include <grub/env.h>
+#include <grub/normal.h>
+#include <grub/gfxwidgets.h>
+#include <grub/menu.h>
+#include <grub/menu_viewer.h>
+#include <grub/gfxmenu_model.h>
+#include <grub/gfxmenu_view.h>
+#include <grub/time.h>
+#include <grub/env.h>
+#include <grub/i18n.h>
+
+GRUB_MOD_LICENSE ("GPLv3+");
+
+extern int g_ventoy_menu_refresh;
+
+static grub_gfxmenu_view_t cached_view;
+
+static void 
+grub_gfxmenu_viewer_fini (void *data __attribute__ ((unused)))
+{
+}
+
+/* FIXME: Previously 't' changed to text menu is it necessary?  */
+static grub_err_t
+grub_gfxmenu_try (int entry, grub_menu_t menu, int nested)
+{
+  int force_refresh = 0;
+  grub_gfxmenu_view_t view = NULL;
+  const char *theme_path;
+  char *full_theme_path = 0;
+  struct grub_menu_viewer *instance;
+  grub_err_t err;
+  struct grub_video_mode_info mode_info;
+
+  theme_path = grub_env_get ("theme");
+  if (! theme_path)
+    return grub_error (GRUB_ERR_FILE_NOT_FOUND, N_("variable `%s' isn't set"),
+		       "theme");
+
+  err = grub_video_get_info (&mode_info);
+  if (err)
+    return err;
+
+  instance = grub_zalloc (sizeof (*instance));
+  if (!instance)
+    return grub_errno;
+
+  if (theme_path[0] != '/' && theme_path[0] != '(')
+    {
+      const char *prefix;
+      prefix = grub_env_get ("prefix");
+      full_theme_path = grub_xasprintf ("%s/themes/%s",
+					prefix,
+					theme_path);
+    }
+
+  if (g_ventoy_menu_refresh)
+  {
+      g_ventoy_menu_refresh = 0;
+      force_refresh = 1;
+  }
+
+  if (force_refresh ||
+      !cached_view || grub_strcmp (cached_view->theme_path,
+				   full_theme_path ? : theme_path) != 0
+      || cached_view->screen.width != mode_info.width
+      || cached_view->screen.height != mode_info.height)
+    {
+      grub_gfxmenu_view_destroy (cached_view);
+      /* Create the view.  */
+      cached_view = grub_gfxmenu_view_new (full_theme_path ? : theme_path,
+					   mode_info.width,
+					   mode_info.height);
+    }
+  grub_free (full_theme_path);
+
+  if (! cached_view)
+    {
+      grub_free (instance);
+      return grub_errno;
+    }
+
+  view = cached_view;
+
+  view->double_repaint = (mode_info.mode_type
+			  & GRUB_VIDEO_MODE_TYPE_DOUBLE_BUFFERED)
+    && !(mode_info.mode_type & GRUB_VIDEO_MODE_TYPE_UPDATING_SWAP);
+  view->selected = entry;
+  view->menu = menu;
+  view->nested = nested;
+  view->first_timeout = -1;
+
+  grub_video_set_viewport (0, 0, mode_info.width, mode_info.height);
+  if (view->double_repaint)
+    {
+      grub_video_swap_buffers ();
+      grub_video_set_viewport (0, 0, mode_info.width, mode_info.height);
+    }
+
+  grub_gfxmenu_view_draw (view);
+
+  instance->data = view;
+  instance->set_chosen_entry = grub_gfxmenu_set_chosen_entry;
+  instance->fini = grub_gfxmenu_viewer_fini;
+  instance->print_timeout = grub_gfxmenu_print_timeout;
+  instance->clear_timeout = grub_gfxmenu_clear_timeout;
+
+  grub_menu_register_viewer (instance);
+
+  return GRUB_ERR_NONE;
+}
+
+GRUB_MOD_INIT (gfxmenu)
+{
+  struct grub_term_output *term;
+
+  FOR_ACTIVE_TERM_OUTPUTS(term)
+    if (grub_gfxmenu_try_hook && term->fullscreen)
+      {
+	term->fullscreen ();
+	break;
+      }
+
+  grub_gfxmenu_try_hook = grub_gfxmenu_try;
+}
+
+GRUB_MOD_FINI (gfxmenu)
+{
+  grub_gfxmenu_view_destroy (cached_view);
+  grub_gfxmenu_try_hook = NULL;
+}

GRUB2/MOD_SRC/grub-2.04/grub-core/gfxmenu/gui_label.c

+/* gui_label.c - GUI component to display a line of text.  */
+/*
+ *  GRUB  --  GRand Unified Bootloader
+ *  Copyright (C) 2008,2009  Free Software Foundation, Inc.
+ *
+ *  GRUB 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.
+ *
+ *  GRUB 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 GRUB.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <grub/mm.h>
+#include <grub/misc.h>
+#include <grub/gui.h>
+#include <grub/font.h>
+#include <grub/gui_string_util.h>
+#include <grub/i18n.h>
+#include <grub/color.h>
+#include <grub/env.h>
+
+extern int g_ventoy_memdisk_mode;
+extern int g_ventoy_iso_raw;
+extern int g_ventoy_iso_uefi_drv;
+
+static const char *align_options[] =
+{
+  "left",
+  "center",
+  "right",
+  0
+};
+
+enum align_mode {
+  align_left,
+  align_center,
+  align_right
+};
+
+struct grub_gui_label
+{
+  struct grub_gui_component comp;
+
+  grub_gui_container_t parent;
+  grub_video_rect_t bounds;
+  char *id;
+  int visible;
+  char *text;
+  char *template;
+  grub_font_t font;
+  grub_video_rgba_color_t color;
+  int value;
+  enum align_mode align;
+};
+
+typedef struct grub_gui_label *grub_gui_label_t;
+
+static void
+label_destroy (void *vself)
+{
+  grub_gui_label_t self = vself;
+  grub_gfxmenu_timeout_unregister ((grub_gui_component_t) self);
+  grub_free (self->text);
+  grub_free (self->template);
+  grub_free (self);
+}
+
+static const char *
+label_get_id (void *vself)
+{
+  grub_gui_label_t self = vself;
+  return self->id;
+}
+
+static int
+label_is_instance (void *vself __attribute__((unused)), const char *type)
+{
+  return grub_strcmp (type, "component") == 0;
+}
+
+static void
+label_paint (void *vself, const grub_video_rect_t *region)
+{
+  grub_gui_label_t self = vself;
+
+  if (! self->visible)
+    return;
+
+  if (!grub_video_have_common_points (region, &self->bounds))
+    return;
+
+  /* Calculate the starting x coordinate.  */
+  int left_x;
+  if (self->align == align_left)
+    left_x = 0;
+  else if (self->align == align_center)
+    left_x = (self->bounds.width
+	      - grub_font_get_string_width (self->font, self->text)) / 2;
+  else if (self->align == align_right)
+    left_x = (self->bounds.width
+              - grub_font_get_string_width (self->font, self->text));
+  else
+    return;   /* Invalid alignment.  */
+
+  if (left_x < 0 || left_x > (int) self->bounds.width)
+    left_x = 0;
+
+  grub_video_rect_t vpsave;
+  grub_gui_set_viewport (&self->bounds, &vpsave);
+  grub_font_draw_string (self->text,
+                         self->font,
+                         grub_video_map_rgba_color (self->color),
+                         left_x,
+                         grub_font_get_ascent (self->font));
+  grub_gui_restore_viewport (&vpsave);
+}
+
+static void
+label_set_parent (void *vself, grub_gui_container_t parent)
+{
+  grub_gui_label_t self = vself;
+  self->parent = parent;
+}
+
+static grub_gui_container_t
+label_get_parent (void *vself)
+{
+  grub_gui_label_t self = vself;
+  return self->parent;
+}
+
+static void
+label_set_bounds (void *vself, const grub_video_rect_t *bounds)
+{
+  grub_gui_label_t self = vself;
+  self->bounds = *bounds;
+}
+
+static void
+label_get_bounds (void *vself, grub_video_rect_t *bounds)
+{
+  grub_gui_label_t self = vself;
+  *bounds = self->bounds;
+}
+
+static void
+label_get_minimal_size (void *vself, unsigned *width, unsigned *height)
+{
+  grub_gui_label_t self = vself;
+  *width = grub_font_get_string_width (self->font, self->text);
+  *height = (grub_font_get_ascent (self->font)
+             + grub_font_get_descent (self->font));
+}
+
+#pragma GCC diagnostic ignored "-Wformat-nonliteral"
+
+static void
+label_set_state (void *vself, int visible, int start __attribute__ ((unused)),
+		 int current, int end __attribute__ ((unused)))
+{
+  grub_gui_label_t self = vself;  
+  self->value = -current;
+  self->visible = visible;
+  grub_free (self->text);
+  self->text = grub_xasprintf (self->template ? : "%d", self->value);
+}
+
+static grub_err_t
+label_set_property (void *vself, const char *name, const char *value)
+{
+  grub_gui_label_t self = vself;
+  if (grub_strcmp (name, "text") == 0)
+    {
+      grub_free (self->text);
+      grub_free (self->template);
+      if (! value)
+	{
+	  self->template = NULL;
+	  self->text = grub_strdup ("");
+	}
+      else
+	{
+	   if (grub_strcmp (value, "@KEYMAP_LONG@") == 0)
+	    value = _("Press enter to boot the selected OS, "
+	       "`e' to edit the commands before booting "
+	       "or `c' for a command-line. ESC to return previous menu.");
+           else if (grub_strcmp (value, "@KEYMAP_MIDDLE@") == 0)
+	    value = _("Press enter to boot the selected OS, "
+	       "`e' to edit the commands before booting "
+	       "or `c' for a command-line.");
+	   else if (grub_strcmp (value, "@KEYMAP_SHORT@") == 0)
+	    value = _("enter: boot, `e': options, `c': cmd-line");
+	   /* FIXME: Add more templates here if needed.  */
+       
+       else if (grub_strcmp (value, "@VTOY_MEM_DISK@") == 0) {
+            value = g_ventoy_memdisk_mode ? grub_env_get("VTOY_MEM_DISK_STR") : " ";
+       }
+       else if (grub_strcmp (value, "@VTOY_ISO_RAW@") == 0) {
+            value = g_ventoy_iso_raw ? grub_env_get("VTOY_ISO_RAW_STR") : " ";
+       }
+       else if (grub_strcmp (value, "@VTOY_ISO_UEFI_DRV@") == 0) {
+            value = g_ventoy_iso_uefi_drv ? grub_env_get("VTOY_ISO_UEFI_DRV_STR") : " ";
+       }
+       else if (grub_strcmp (value, "@VTOY_HOTKEY_TIP@") == 0) {
+            value = grub_env_get("VTOY_HOTKEY_TIP");
+            if (value == NULL) {
+                value = _(" ");
+            }
+       }
+       
+	  self->template = grub_strdup (value);
+	  self->text = grub_xasprintf (value, self->value);
+	}
+    }
+  else if (grub_strcmp (name, "font") == 0)
+    {
+      self->font = grub_font_get (value);
+    }
+  else if (grub_strcmp (name, "color") == 0)
+    {
+      grub_video_parse_color (value, &self->color);
+    }
+  else if (grub_strcmp (name, "align") == 0)
+    {
+      int i;
+      for (i = 0; align_options[i]; i++)
+        {
+          if (grub_strcmp (align_options[i], value) == 0)
+            {
+              self->align = i;   /* Set the alignment mode.  */
+              break;
+            }
+        }
+    }
+  else if (grub_strcmp (name, "visible") == 0)
+    {
+      self->visible = grub_strcmp (value, "false") != 0;
+    }
+  else if (grub_strcmp (name, "id") == 0)
+    {
+      grub_gfxmenu_timeout_unregister ((grub_gui_component_t) self);
+      grub_free (self->id);
+      if (value)
+        self->id = grub_strdup (value);
+      else
+        self->id = 0;
+      if (self->id && grub_strcmp (self->id, GRUB_GFXMENU_TIMEOUT_COMPONENT_ID)
+	  == 0)
+	grub_gfxmenu_timeout_register ((grub_gui_component_t) self,
+				       label_set_state);
+    }
+  return GRUB_ERR_NONE;
+}
+
+#pragma GCC diagnostic error "-Wformat-nonliteral"
+
+static struct grub_gui_component_ops label_ops =
+{
+  .destroy = label_destroy,
+  .get_id = label_get_id,
+  .is_instance = label_is_instance,
+  .paint = label_paint,
+  .set_parent = label_set_parent,
+  .get_parent = label_get_parent,
+  .set_bounds = label_set_bounds,
+  .get_bounds = label_get_bounds,
+  .get_minimal_size = label_get_minimal_size,
+  .set_property = label_set_property
+};
+
+grub_gui_component_t
+grub_gui_label_new (void)
+{
+  grub_gui_label_t label;
+  label = grub_zalloc (sizeof (*label));
+  if (! label)
+    return 0;
+  label->comp.ops = &label_ops;
+  label->visible = 1;
+  label->text = grub_strdup ("");
+  label->font = grub_font_get ("Unknown Regular 16");
+  label->color.red = 0;
+  label->color.green = 0;
+  label->color.blue = 0;
+  label->color.alpha = 255;
+  label->align = align_left;
+  return (grub_gui_component_t) label;
+}