theme

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

+/* theme_loader.c - Theme file loader for gfxmenu.  */
+/*
+ *  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/file.h>
+#include <grub/misc.h>
+#include <grub/mm.h>
+#include <grub/err.h>
+#include <grub/dl.h>
+#include <grub/video.h>
+#include <grub/gui_string_util.h>
+#include <grub/bitmap.h>
+#include <grub/bitmap_scale.h>
+#include <grub/gfxwidgets.h>
+#include <grub/gfxmenu_view.h>
+#include <grub/gui.h>
+#include <grub/color.h>
+#include <grub/env.h>
+
+static grub_err_t
+parse_proportional_spec (const char *value, signed *abs, grub_fixed_signed_t *prop);
+
+/* Construct a new box widget using ABSPATTERN to find the pixmap files for
+   it, storing the new box instance at *BOXPTR.
+   PATTERN should be of the form: "(hd0,0)/somewhere/style*.png".
+   The '*' then gets substituted with the various pixmap names that the
+   box uses.  */
+static grub_err_t
+recreate_box_absolute (grub_gfxmenu_box_t *boxptr, const char *abspattern)
+{
+  char *prefix;
+  char *suffix;
+  char *star;
+  grub_gfxmenu_box_t box;
+
+  star = grub_strchr (abspattern, '*');
+  if (! star)
+    return grub_error (GRUB_ERR_BAD_ARGUMENT,
+                       "missing `*' in box pixmap pattern `%s'", abspattern);
+
+  /* Prefix:  Get the part before the '*'.  */
+  prefix = grub_malloc (star - abspattern + 1);
+  if (! prefix)
+    return grub_errno;
+
+  grub_memcpy (prefix, abspattern, star - abspattern);
+  prefix[star - abspattern] = '\0';
+
+  /* Suffix:  Everything after the '*' is the suffix.  */
+  suffix = star + 1;
+
+  box = grub_gfxmenu_create_box (prefix, suffix);
+  grub_free (prefix);
+  if (! box)
+    return grub_errno;
+
+  if (*boxptr)
+    (*boxptr)->destroy (*boxptr);
+  *boxptr = box;
+  return grub_errno;
+}
+
+
+/* Construct a new box widget using PATTERN to find the pixmap files for it,
+   storing the new widget at *BOXPTR.  PATTERN should be of the form:
+   "somewhere/style*.png".  The '*' then gets substituted with the various
+   pixmap names that the widget uses.
+
+   Important!  The value of *BOXPTR must be initialized!  It must either
+   (1) Be 0 (a NULL pointer), or
+   (2) Be a pointer to a valid 'grub_gfxmenu_box_t' instance.
+   In this case, the previous instance is destroyed.  */
+grub_err_t
+grub_gui_recreate_box (grub_gfxmenu_box_t *boxptr,
+                       const char *pattern, const char *theme_dir)
+{
+  char *abspattern;
+
+  /* Check arguments.  */
+  if (! pattern)
+    {
+      /* If no pixmap pattern is given, then just create an empty box.  */
+      if (*boxptr)
+        (*boxptr)->destroy (*boxptr);
+      *boxptr = grub_gfxmenu_create_box (0, 0);
+      return grub_errno;
+    }
+
+  if (! theme_dir)
+    return grub_error (GRUB_ERR_BAD_ARGUMENT,
+                       "styled box missing theme directory");
+
+  /* Resolve to an absolute path.  */
+  abspattern = grub_resolve_relative_path (theme_dir, pattern);
+  if (! abspattern)
+    return grub_errno;
+
+  /* Create the box.  */
+  recreate_box_absolute (boxptr, abspattern);
+  grub_free (abspattern);
+  return grub_errno;
+}
+
+static grub_err_t
+theme_get_unsigned_int_from_proportional (const char *value,
+                                          unsigned absolute_value,
+                                          unsigned int *parsed_value)
+{
+  grub_err_t err;
+  grub_fixed_signed_t frac;
+  signed pixels;
+  err = parse_proportional_spec (value, &pixels, &frac);
+  if (err != GRUB_ERR_NONE)
+    return err;
+  int result = grub_fixed_sfs_multiply (absolute_value, frac) + pixels;
+  if (result < 0)
+    result = 0;
+  *parsed_value = result;
+  return GRUB_ERR_NONE;
+}
+
+/* Set the specified property NAME on the view to the given string VALUE.
+   The caller is responsible for the lifetimes of NAME and VALUE.  */
+static grub_err_t
+theme_set_string (grub_gfxmenu_view_t view,
+                  const char *name,
+                  const char *value,
+                  const char *theme_dir,
+                  const char *filename,
+                  int line_num,
+                  int col_num)
+{
+  if (! grub_strcmp ("title-font", name))
+    view->title_font = grub_font_get (value);
+  else if (! grub_strcmp ("message-font", name))
+    view->message_font = grub_font_get (value);
+  else if (! grub_strcmp ("terminal-font", name))
+    {
+      grub_free (view->terminal_font_name);
+      view->terminal_font_name = grub_strdup (value);
+      if (! view->terminal_font_name)
+        return grub_errno;
+    }
+  else if (! grub_strcmp ("title-color", name))
+    grub_video_parse_color (value, &view->title_color);
+  else if (! grub_strcmp ("message-color", name))
+    grub_video_parse_color (value, &view->message_color);
+  else if (! grub_strcmp ("message-bg-color", name))
+    grub_video_parse_color (value, &view->message_bg_color);
+  else if (! grub_strcmp ("desktop-image", name))
+    {
+      struct grub_video_bitmap *raw_bitmap;
+      char *path;
+      path = grub_resolve_relative_path (theme_dir, value);
+      if (! path)
+        return grub_errno;
+      if (grub_video_bitmap_load (&raw_bitmap, path) != GRUB_ERR_NONE)
+        {
+          grub_free (path);
+          return grub_errno;
+        }
+      grub_free(path);
+      grub_video_bitmap_destroy (view->raw_desktop_image);
+      view->raw_desktop_image = raw_bitmap;
+    }
+  else if (! grub_strcmp ("desktop-image-scale-method", name))
+    {
+      if (! value || ! grub_strcmp ("stretch", value))
+        view->desktop_image_scale_method =
+            GRUB_VIDEO_BITMAP_SELECTION_METHOD_STRETCH;
+      else if (! grub_strcmp ("crop", value))
+        view->desktop_image_scale_method =
+            GRUB_VIDEO_BITMAP_SELECTION_METHOD_CROP;
+      else if (! grub_strcmp ("padding", value))
+        view->desktop_image_scale_method =
+            GRUB_VIDEO_BITMAP_SELECTION_METHOD_PADDING;
+      else if (! grub_strcmp ("fitwidth", value))
+        view->desktop_image_scale_method =
+            GRUB_VIDEO_BITMAP_SELECTION_METHOD_FITWIDTH;
+      else if (! grub_strcmp ("fitheight", value))
+        view->desktop_image_scale_method =
+            GRUB_VIDEO_BITMAP_SELECTION_METHOD_FITHEIGHT;
+      else
+        return grub_error (GRUB_ERR_BAD_ARGUMENT,
+                           "Unsupported scale method: %s",
+                           value);
+    }
+  else if (! grub_strcmp ("desktop-image-h-align", name))
+    {
+      if (! grub_strcmp ("left", value))
+        view->desktop_image_h_align = GRUB_VIDEO_BITMAP_H_ALIGN_LEFT;
+      else if (! grub_strcmp ("center", value))
+        view->desktop_image_h_align = GRUB_VIDEO_BITMAP_H_ALIGN_CENTER;
+      else if (! grub_strcmp ("right", value))
+        view->desktop_image_h_align = GRUB_VIDEO_BITMAP_H_ALIGN_RIGHT;
+      else
+        return grub_error (GRUB_ERR_BAD_ARGUMENT,
+                           "Unsupported horizontal align method: %s",
+                           value);
+    }
+  else if (! grub_strcmp ("desktop-image-v-align", name))
+    {
+      if (! grub_strcmp ("top", value))
+        view->desktop_image_v_align = GRUB_VIDEO_BITMAP_V_ALIGN_TOP;
+      else if (! grub_strcmp ("center", value))
+        view->desktop_image_v_align = GRUB_VIDEO_BITMAP_V_ALIGN_CENTER;
+      else if (! grub_strcmp ("bottom", value))
+        view->desktop_image_v_align = GRUB_VIDEO_BITMAP_V_ALIGN_BOTTOM;
+      else
+        return grub_error (GRUB_ERR_BAD_ARGUMENT,
+                           "Unsupported vertical align method: %s",
+                           value);
+    }
+  else if (! grub_strcmp ("desktop-color", name))
+     grub_video_parse_color (value, &view->desktop_color);
+  else if (! grub_strcmp ("terminal-box", name))
+    {
+        grub_err_t err;
+        err = grub_gui_recreate_box (&view->terminal_box, value, theme_dir);
+        if (err != GRUB_ERR_NONE)
+          return err;
+    }
+  else if (! grub_strcmp ("terminal-border", name))
+    {
+      view->terminal_border = grub_strtoul (value, 0, 10);
+      if (grub_errno)
+        return grub_errno;
+    }
+  else if (! grub_strcmp ("terminal-left", name))
+    {
+      unsigned int tmp;
+      int err = theme_get_unsigned_int_from_proportional (value,
+                                                          view->screen.width,
+                                                          &tmp);
+      if (err != GRUB_ERR_NONE)
+        return err;
+      view->terminal_rect.x = tmp;
+    }
+  else if (! grub_strcmp ("terminal-top", name))
+    {
+      unsigned int tmp;
+      int err = theme_get_unsigned_int_from_proportional (value,
+                                                          view->screen.height,
+                                                          &tmp);
+      if (err != GRUB_ERR_NONE)
+        return err;
+      view->terminal_rect.y = tmp;
+    }
+  else if (! grub_strcmp ("terminal-width", name))
+    {
+      unsigned int tmp;
+      int err = theme_get_unsigned_int_from_proportional (value,
+                                                          view->screen.width,
+                                                          &tmp);
+      if (err != GRUB_ERR_NONE)
+        return err;
+      view->terminal_rect.width = tmp;
+    }
+  else if (! grub_strcmp ("terminal-height", name))
+    {
+      unsigned int tmp;
+      int err = theme_get_unsigned_int_from_proportional (value,
+                                                          view->screen.height,
+                                                          &tmp);
+      if (err != GRUB_ERR_NONE)
+        return err;
+      view->terminal_rect.height = tmp;
+    }
+  else if (! grub_strcmp ("title-text", name))
+    {
+      grub_free (view->title_text);
+      view->title_text = grub_strdup (value);
+      if (! view->title_text)
+        return grub_errno;
+    }
+  else
+    {
+      return grub_error (GRUB_ERR_BAD_ARGUMENT,
+                         "%s:%d:%d unknown property `%s'",
+                         filename, line_num, col_num, name);
+    }
+  return grub_errno;
+}
+
+struct parsebuf
+{
+  char *buf;
+  int pos;
+  int len;
+  int line_num;
+  int col_num;
+  const char *filename;
+  char *theme_dir;
+  grub_gfxmenu_view_t view;
+};
+
+static int
+has_more (struct parsebuf *p)
+{
+  return p->pos < p->len;
+}
+
+static int
+read_char (struct parsebuf *p)
+{
+  if (has_more (p))
+    {
+      char c;
+      c = p->buf[p->pos++];
+      if (c == '\n')
+        {
+          p->line_num++;
+          p->col_num = 1;
+        }
+      else
+        {
+          p->col_num++;
+        }
+      return c;
+    }
+  else
+    return -1;
+}
+
+static int
+peek_char (struct parsebuf *p)
+{
+  if (has_more (p))
+    return p->buf[p->pos];
+  else
+    return -1;
+}
+
+static int
+is_whitespace (char c)
+{
+  return (c == ' '
+          || c == '\t'
+          || c == '\r'
+          || c == '\n'
+          || c == '\f');
+}
+
+static void
+skip_whitespace (struct parsebuf *p)
+{
+  while (has_more (p) && is_whitespace(peek_char (p)))
+    read_char (p);
+}
+
+static void
+advance_to_next_line (struct parsebuf *p)
+{
+  int c;
+
+  /* Eat characters up to the newline.  */
+  do
+    {
+      c = read_char (p);
+    }
+  while (c != -1 && c != '\n');
+}
+
+static int
+is_identifier_char (int c)
+{
+  return (c != -1
+          && (grub_isalpha(c)
+              || grub_isdigit(c)
+              || c == '_'
+              || c == '-'));
+}
+
+static char *
+read_identifier (struct parsebuf *p)
+{
+  /* Index of the first character of the identifier in p->buf.  */
+  int start;
+  /* Next index after the last character of the identifer in p->buf.  */
+  int end;
+
+  skip_whitespace (p);
+
+  /* Capture the start of the identifier.  */
+  start = p->pos;
+
+  /* Scan for the end.  */
+  while (is_identifier_char (peek_char (p)))
+    read_char (p);
+  end = p->pos;
+
+  if (end - start < 1)
+    return 0;
+
+  return grub_new_substring (p->buf, start, end);
+}
+
+static char *
+read_expression (struct parsebuf *p)
+{
+  int start;
+  int end;
+
+  skip_whitespace (p);
+  if (peek_char (p) == '"')
+    {
+      /* Read as a quoted string.  
+         The quotation marks are not included in the expression value.  */
+      /* Skip opening quotation mark.  */
+      read_char (p);
+      start = p->pos;
+      while (has_more (p) && peek_char (p) != '"')
+        read_char (p);
+      end = p->pos;
+      /* Skip the terminating quotation mark.  */
+      read_char (p);
+    }
+  else if (peek_char (p) == '(')
+    {
+      /* Read as a parenthesized string -- for tuples/coordinates.  */
+      /* The parentheses are included in the expression value.  */
+      int c;
+
+      start = p->pos;
+      do
+        {
+          c = read_char (p);
+        }
+      while (c != -1 && c != ')');
+      end = p->pos;
+    }
+  else if (has_more (p))
+    {
+      /* Read as a single word -- for numeric values or words without
+         whitespace.  */
+      start = p->pos;
+      while (has_more (p) && ! is_whitespace (peek_char (p)))
+        read_char (p);
+      end = p->pos;
+    }
+  else
+    {
+      /* The end of the theme file has been reached.  */
+      grub_error (GRUB_ERR_IO, "%s:%d:%d expression expected in theme file",
+                  p->filename, p->line_num, p->col_num);
+      return 0;
+    }
+
+  return grub_new_substring (p->buf, start, end);
+}
+
+static grub_err_t
+parse_proportional_spec (const char *value, signed *abs, grub_fixed_signed_t *prop)
+{
+  signed num;
+  const char *ptr;
+  int sig = 0;
+  *abs = 0;
+  *prop = 0;
+  ptr = value;
+  while (*ptr)
+    {
+      sig = 0;
+
+      while (*ptr == '-' || *ptr == '+')
+	{
+	  if (*ptr == '-')
+	    sig = !sig;
+	  ptr++;
+	}
+
+      num = grub_strtoul (ptr, (char **) &ptr, 0);
+      if (grub_errno)
+	return grub_errno;
+      if (sig)
+	num = -num;
+      if (*ptr == '%')
+	{
+	  *prop += grub_fixed_fsf_divide (grub_signed_to_fixed (num), 100);
+	  ptr++;
+	}
+      else
+	*abs += num;
+    }
+  return GRUB_ERR_NONE;
+}
+
+
+/* Read a GUI object specification from the theme file.
+   Any components created will be added to the GUI container PARENT.  */
+static grub_err_t
+read_object (struct parsebuf *p, grub_gui_container_t parent)
+{
+  grub_video_rect_t bounds;
+
+  char *name;
+  name = read_identifier (p);
+  if (! name)
+    goto cleanup;
+
+  grub_gui_component_t component = 0;
+  if (grub_strcmp (name, "label") == 0)
+    {
+      component = grub_gui_label_new ();
+    }
+  else if (grub_strcmp (name, "image") == 0)
+    {
+      component = grub_gui_image_new ();
+    }
+  else if (grub_strcmp (name, "vbox") == 0)
+    {
+      component = (grub_gui_component_t) grub_gui_vbox_new ();
+    }
+  else if (grub_strcmp (name, "hbox") == 0)
+    {
+      component = (grub_gui_component_t) grub_gui_hbox_new ();
+    }
+  else if (grub_strcmp (name, "canvas") == 0)
+    {
+      component = (grub_gui_component_t) grub_gui_canvas_new ();
+    }
+  else if (grub_strcmp (name, "progress_bar") == 0)
+    {
+      component = grub_gui_progress_bar_new ();
+    }
+  else if (grub_strcmp (name, "circular_progress") == 0)
+    {
+      component = grub_gui_circular_progress_new ();
+    }
+  else if (grub_strcmp (name, "boot_menu") == 0)
+    {
+      component = grub_gui_list_new ();
+    }
+  else
+    {
+      /* Unknown type.  */
+      grub_error (GRUB_ERR_IO, "%s:%d:%d unknown object type `%s'",
+                  p->filename, p->line_num, p->col_num, name);
+      goto cleanup;
+    }
+
+  if (! component)
+    goto cleanup;
+
+  /* Inform the component about the theme so it can find its resources.  */
+  component->ops->set_property (component, "theme_dir", p->theme_dir);
+  component->ops->set_property (component, "theme_path", p->filename);
+
+  /* Add the component as a child of PARENT.  */
+  bounds.x = 0;
+  bounds.y = 0;
+  bounds.width = -1;
+  bounds.height = -1;
+  component->ops->set_bounds (component, &bounds);
+  parent->ops->add (parent, component);
+
+  skip_whitespace (p);
+  if (read_char (p) != '{')
+    {
+      grub_error (GRUB_ERR_IO,
+                  "%s:%d:%d expected `{' after object type name `%s'",
+                  p->filename, p->line_num, p->col_num, name);
+      goto cleanup;
+    }
+
+  while (has_more (p))
+    {
+      skip_whitespace (p);
+
+      /* Check whether the end has been encountered.  */
+      if (peek_char (p) == '}')
+        {
+          /* Skip the closing brace.  */
+          read_char (p);
+          break;
+        }
+
+      if (peek_char (p) == '#')
+        {
+          /* Skip comments.  */
+          advance_to_next_line (p);
+          continue;
+        }
+
+      if (peek_char (p) == '+')
+        {
+          /* Skip the '+'.  */
+          read_char (p);
+
+          /* Check whether this component is a container.  */
+          if (component->ops->is_instance (component, "container"))
+            {
+              /* Read the sub-object recursively and add it as a child.  */
+              if (read_object (p, (grub_gui_container_t) component) != 0)
+                goto cleanup;
+              /* After reading the sub-object, resume parsing, expecting
+                 another property assignment or sub-object definition.  */
+              continue;
+            }
+          else
+            {
+              grub_error (GRUB_ERR_IO,
+                          "%s:%d:%d attempted to add object to non-container",
+                          p->filename, p->line_num, p->col_num);
+              goto cleanup;
+            }
+        }
+
+      char *property;
+      property = read_identifier (p);
+      if (! property)
+        {
+          grub_error (GRUB_ERR_IO, "%s:%d:%d identifier expected in theme file",
+                      p->filename, p->line_num, p->col_num);
+          goto cleanup;
+        }
+
+      skip_whitespace (p);
+      if (read_char (p) != '=')
+        {
+          grub_error (GRUB_ERR_IO,
+                      "%s:%d:%d expected `=' after property name `%s'",
+                      p->filename, p->line_num, p->col_num, property);
+          grub_free (property);
+          goto cleanup;
+        }
+      skip_whitespace (p);
+
+      char *value;
+      value = read_expression (p);
+      if (! value)
+        {
+          grub_free (property);
+          goto cleanup;
+        }
+
+      /* Handle the property value.  */
+      if (grub_strcmp (property, "left") == 0)
+	parse_proportional_spec (value, &component->x, &component->xfrac);
+      else if (grub_strcmp (property, "top") == 0)
+	parse_proportional_spec (value, &component->y, &component->yfrac);
+      else if (grub_strcmp (property, "width") == 0)
+	parse_proportional_spec (value, &component->w, &component->wfrac);
+      else if (grub_strcmp (property, "height") == 0)
+	parse_proportional_spec (value, &component->h, &component->hfrac);
+      else
+	/* General property handling.  */
+	component->ops->set_property (component, property, value);
+
+      grub_free (value);
+      grub_free (property);
+      if (grub_errno != GRUB_ERR_NONE)
+        goto cleanup;
+    }
+
+cleanup:
+  grub_free (name);
+  return grub_errno;
+}
+
+static grub_err_t
+read_property (struct parsebuf *p)
+{
+  char *name;
+
+  /* Read the property name.  */
+  name = read_identifier (p);
+  if (! name)
+    {
+      advance_to_next_line (p);
+      return grub_errno;
+    }
+
+  /* Skip whitespace before separator.  */
+  skip_whitespace (p);
+
+  /* Read separator.  */
+  if (read_char (p) != ':')
+    {
+      grub_error (GRUB_ERR_IO,
+                  "%s:%d:%d missing separator after property name `%s'",
+                  p->filename, p->line_num, p->col_num, name);
+      goto done;
+    }
+
+  /* Skip whitespace after separator.  */
+  skip_whitespace (p);
+
+  /* Get the value based on its type.  */
+  if (peek_char (p) == '"')
+    {
+      /* String value (e.g., '"My string"').  */
+      char *value = read_expression (p);
+      if (! value)
+        {
+          grub_error (GRUB_ERR_IO, "%s:%d:%d missing property value",
+                      p->filename, p->line_num, p->col_num);
+          goto done;
+        }
+      /* If theme_set_string results in an error, grub_errno will be returned
+         below.  */
+      theme_set_string (p->view, name, value, p->theme_dir,
+                        p->filename, p->line_num, p->col_num);
+      grub_free (value);
+    }
+  else
+    {
+      grub_error (GRUB_ERR_IO,
+                  "%s:%d:%d property value invalid; "
+                  "enclose literal values in quotes (\")",
+                  p->filename, p->line_num, p->col_num);
+      goto done;
+    }
+
+done:
+  grub_free (name);
+  return grub_errno;
+}
+
+/* Set properties on the view based on settings from the specified
+   theme file.  */
+grub_err_t
+grub_gfxmenu_view_load_theme (grub_gfxmenu_view_t view, const char *theme_path)
+{
+  grub_file_t file;
+  struct parsebuf p;
+
+  p.view = view;
+  p.theme_dir = grub_get_dirname (theme_path);
+
+  file = grub_file_open (theme_path, GRUB_FILE_TYPE_THEME);
+  if (! file)
+    {
+      grub_free (p.theme_dir);
+      return grub_errno;
+    }
+
+  p.len = grub_file_size (file);
+  p.buf = grub_malloc (p.len + 4096);
+  p.pos = 0;
+  p.line_num = 1;
+  p.col_num = 1;
+  p.filename = theme_path;
+  if (! p.buf)
+    {
+      grub_file_close (file);
+      grub_free (p.theme_dir);
+      return grub_errno;
+    }
+  if (grub_file_read (file, p.buf, p.len) != p.len)
+    {
+      grub_free (p.buf);
+      grub_file_close (file);
+      grub_free (p.theme_dir);
+      return grub_errno;
+    }
+
+{
+  const char *checkret = grub_env_get("VTOY_CHKDEV_RESULT_STRING");
+  if (checkret == NULL || checkret[0] != '0')
+  {
+    p.len += grub_snprintf(p.buf + p.len, 4096, "\n+ hbox{\n    left = 1%%\n    top = 90%%\n"
+      "    + label {text = \"[Unofficial Ventoy]\" color = \"red\" align = \"left\"}\n"
+      "}\n");    
+  }
+}
+
+  if (view->canvas)
+    view->canvas->component.ops->destroy (view->canvas);
+
+  view->canvas = grub_gui_canvas_new ();
+  if (!view->canvas)
+    goto fail;
+  ((grub_gui_component_t) view->canvas)
+    ->ops->set_bounds ((grub_gui_component_t) view->canvas,
+                       &view->screen);
+
+  while (has_more (&p))
+    {
+      /* Skip comments (lines beginning with #).  */
+      if (peek_char (&p) == '#')
+        {
+          advance_to_next_line (&p);
+          continue;
+        }
+
+      /* Find the first non-whitespace character.  */
+      skip_whitespace (&p);
+
+      /* Handle the content.  */
+      if (peek_char (&p) == '+')
+        {
+          /* Skip the '+'.  */
+          read_char (&p);
+          read_object (&p, view->canvas);
+        }
+      else
+        {
+          read_property (&p);
+        }
+
+      if (grub_errno != GRUB_ERR_NONE)
+        goto fail;
+    }
+
+  /* Set the new theme path.  */
+  grub_free (view->theme_path);
+  view->theme_path = grub_strdup (theme_path);
+  goto cleanup;
+
+fail:
+  if (view->canvas)
+    {
+      view->canvas->component.ops->destroy (view->canvas);
+      view->canvas = 0;
+    }
+
+cleanup:
+  grub_free (p.buf);
+  grub_file_close (file);
+  grub_free (p.theme_dir);
+  return grub_errno;
+}