gfxmenu import

gfxmenu/gui_canvas.c

@@ -0,0 +1,268 @@
+/* gui_canvas.c - GUI container allowing manually placed components. */
+/*
+ *  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/gui_string_util.h>
+
+/* TODO Add layering so that components can be properly overlaid. */
+
+struct component_node
+{
+  grub_gui_component_t component;
+  struct component_node *next;
+};
+
+struct grub_gui_canvas
+{
+  struct grub_gui_container_ops *container;
+
+  grub_gui_container_t parent;
+  grub_video_rect_t bounds;
+  char *id;
+  int preferred_width;
+  int preferred_height;
+  /* Component list (dummy head node).  */
+  struct component_node components;
+};
+
+typedef struct grub_gui_canvas *grub_gui_canvas_t;
+
+static void
+canvas_destroy (void *vself)
+{
+  grub_gui_canvas_t self = vself;
+  struct component_node *cur;
+  struct component_node *next;
+  for (cur = self->components.next; cur; cur = next)
+    {
+      /* Copy the 'next' pointer, since we need it for the next iteration,
+         and we're going to free the memory it is stored in.  */
+      next = cur->next;
+      /* Destroy the child component.  */
+      cur->component->ops->destroy (cur->component);
+      /* Free the linked list node.  */
+      grub_free (cur);
+    }
+  grub_free (self);
+}
+
+static const char *
+canvas_get_id (void *vself)
+{
+  grub_gui_canvas_t self = vself;
+  return self->id;
+}
+
+static int
+canvas_is_instance (void *vself __attribute__((unused)), const char *type)
+{
+  return (grub_strcmp (type, "component") == 0
+          || grub_strcmp (type, "container") == 0);
+}
+
+static void
+canvas_paint (void *vself)
+{
+  grub_gui_canvas_t self = vself;
+  struct component_node *cur;
+  grub_video_rect_t vpsave;
+
+  grub_gui_set_viewport (&self->bounds, &vpsave);
+  for (cur = self->components.next; cur; cur = cur->next)
+    {
+      int pw;
+      int ph;
+      grub_video_rect_t r;
+      grub_gui_component_t comp;
+
+      comp = cur->component;
+
+      /* Give the child its preferred size.  */
+      comp->ops->get_preferred_size (comp, &pw, &ph);
+      comp->ops->get_bounds (comp, &r);
+      if (r.width != pw || r.height != ph)
+        {
+          r.width = pw;
+          r.height = ph;
+          comp->ops->set_bounds (comp, &r);
+        }
+
+      /* Paint the child.  */
+      comp->ops->paint (comp);
+    }
+  grub_gui_restore_viewport (&vpsave);
+}
+
+static void
+canvas_set_parent (void *vself, grub_gui_container_t parent)
+{
+  grub_gui_canvas_t self = vself;
+  self->parent = parent;
+}
+
+static grub_gui_container_t
+canvas_get_parent (void *vself)
+{
+  grub_gui_canvas_t self = vself;
+  return self->parent;
+}
+
+static void
+canvas_set_bounds (void *vself, const grub_video_rect_t *bounds)
+{
+  grub_gui_canvas_t self = vself;
+  self->bounds = *bounds;
+}
+
+static void
+canvas_get_bounds (void *vself, grub_video_rect_t *bounds)
+{
+  grub_gui_canvas_t self = vself;
+  *bounds = self->bounds;
+}
+
+static void
+canvas_get_preferred_size (void *vself, int *width, int *height)
+{
+  grub_gui_canvas_t self = vself;
+  *width = 0;
+  *height = 0;
+
+  /* Allow preferred dimensions to override the empty dimensions.  */
+  if (self->preferred_width >= 0)
+    *width = self->preferred_width;
+  if (self->preferred_height >= 0)
+    *height = self->preferred_height;
+}
+
+static grub_err_t
+canvas_set_property (void *vself, const char *name, const char *value)
+{
+  grub_gui_canvas_t self = vself;
+  if (grub_strcmp (name, "id") == 0)
+    {
+      grub_free (self->id);
+      if (value)
+        {
+          self->id = grub_strdup (value);
+          if (! self->id)
+            return grub_errno;
+        }
+      else
+        self->id = 0;
+    }
+  else if (grub_strcmp (name, "preferred_size") == 0)
+    {
+      int w;
+      int h;
+      if (grub_gui_parse_2_tuple (value, &w, &h) != GRUB_ERR_NONE)
+        return grub_errno;
+      self->preferred_width = w;
+      self->preferred_height = h;
+    }
+  return grub_errno;
+}
+
+static void
+canvas_add (void *vself, grub_gui_component_t comp)
+{
+  grub_gui_canvas_t self = vself;
+  struct component_node *node;
+  node = grub_malloc (sizeof (*node));
+  if (! node)
+    return;   /* Note: probably should handle the error.  */
+  node->component = comp;
+  node->next = self->components.next;
+  self->components.next = node;
+  comp->ops->set_parent (comp, (grub_gui_container_t) self);
+}
+
+static void
+canvas_remove (void *vself, grub_gui_component_t comp)
+{
+  grub_gui_canvas_t self = vself;
+  struct component_node *cur;
+  struct component_node *prev;
+  prev = &self->components;
+  for (cur = self->components.next; cur; prev = cur, cur = cur->next)
+    {
+      if (cur->component == comp)
+        {
+          /* Unlink 'cur' from the list.  */
+          prev->next = cur->next;
+          /* Free the node's memory (but don't destroy the component).  */
+          grub_free (cur);
+          /* Must not loop again, since 'cur' would be dereferenced!  */
+          return;
+        }
+    }
+}
+
+static void
+canvas_iterate_children (void *vself,
+                         grub_gui_component_callback cb, void *userdata)
+{
+  grub_gui_canvas_t self = vself;
+  struct component_node *cur;
+  for (cur = self->components.next; cur; cur = cur->next)
+    cb (cur->component, userdata);
+}
+
+static struct grub_gui_container_ops canvas_ops =
+{
+  .component =
+    {
+      .destroy = canvas_destroy,
+      .get_id = canvas_get_id,
+      .is_instance = canvas_is_instance,
+      .paint = canvas_paint,
+      .set_parent = canvas_set_parent,
+      .get_parent = canvas_get_parent,
+      .set_bounds = canvas_set_bounds,
+      .get_bounds = canvas_get_bounds,
+      .get_preferred_size = canvas_get_preferred_size,
+      .set_property = canvas_set_property
+    },
+  .add = canvas_add,
+  .remove = canvas_remove,
+  .iterate_children = canvas_iterate_children
+};
+
+grub_gui_container_t
+grub_gui_canvas_new (void)
+{
+  grub_gui_canvas_t canvas;
+  canvas = grub_malloc (sizeof (*canvas));
+  if (! canvas)
+    return 0;
+  canvas->container = &canvas_ops;
+  canvas->parent = 0;
+  canvas->bounds.x = 0;
+  canvas->bounds.y = 0;
+  canvas->bounds.width = 0;
+  canvas->bounds.height = 0;
+  canvas->id = 0;
+  canvas->preferred_width = -1;
+  canvas->preferred_height = -1;
+  canvas->components.component = 0;
+  canvas->components.next = 0;
+  return (grub_gui_container_t) canvas;
+}