libwidget: Add initial window drawing + cleanups

Introduce the initial logic to draw windows as well as tidying up the
interface a bit.

- All callbacks must now have a state arguments
- The libwidget state is now kept internally
- Add helper to get pixel index
- Add initial window drawing

Signed-off-by: Ian Moffett <ian@osmora.org>

4 files changed, 43 insertions, 13 deletions

diff --git a/src/lib/libwidget/include/libwidget/core.h b/src/lib/libwidget/include/libwidget/core.h
index 85b33d4..074edc4 100644
--- a/src/lib/libwidget/include/libwidget/core.h
+++ b/src/lib/libwidget/include/libwidget/core.h
@@ -30,12 +30,14 @@
 #ifndef LIBWIDGET_CORE_H
 #define LIBWIDGET_CORE_H 1
 
+#include <sys/fbdev.h>
 #include <stdint.h>
 
 /* Forward declarations */
 struct widget;
 
 struct libwidget_state {
+    struct fb_info fbinfo;
     uint32_t *fbdev;
 };
 
@@ -82,8 +84,8 @@ struct blueprint {
  * @draw: Draw the widget
  */
 struct widget_ops {
-    int(*init)(struct widget *wp);
-    int(*draw)(struct widget *wp);
+    int(*init)(struct libwidget_state *lws, struct widget *wp);
+    int(*draw)(struct libwidget_state *lws, struct widget *wp);
 };
 
 /*
@@ -106,12 +108,10 @@ struct widget {
 /*
  * Initialize the library
  *
- * @lwsp: Libwidget state pointer
- *
  * Returns zero on success, otherwise a less than zero
  * value on failure.
  */
-int libwidget_init(struct libwidget_state *lwsp);
+int libwidget_init(void);
 
 /*
  * Initialize a widget
diff --git a/src/lib/libwidget/include/libwidget/window.h b/src/lib/libwidget/include/libwidget/window.h
index 2dc58b1..8823eba 100644
--- a/src/lib/libwidget/include/libwidget/window.h
+++ b/src/lib/libwidget/include/libwidget/window.h
@@ -30,6 +30,7 @@
 #ifndef LIBWIDGET_WINDOW_H
 #define LIBWIDGET_WINDOW_H
 
+#include <sys/cdefs.h>
 #include <libwidget/core.h>
 
 /*
@@ -41,6 +42,12 @@ struct window {
     struct widget *wp;
 };
 
+__always_inline static inline size_t
+get_pix_index(struct fb_info *info, uint32_t x, uint32_t y)
+{
+    return x + y * (info->pitch / 4);
+}
+
 extern struct widget_ops g_winops;
 
 #endif  /* !LIBWIDGET_WINDOW_H */
diff --git a/src/lib/libwidget/src/core/parts/window.c b/src/lib/libwidget/src/core/parts/window.c
index 7425407..236b272 100644
--- a/src/lib/libwidget/src/core/parts/window.c
+++ b/src/lib/libwidget/src/core/parts/window.c
@@ -45,7 +45,7 @@ static uint8_t next_window = 0;
  *       and using a window array, change this when we can
  */
 static int
-window_init(struct widget *wp)
+window_init(struct libwidget_state *lws, struct widget *wp)
 {
     struct window *win;
 
@@ -59,12 +59,31 @@ window_init(struct widget *wp)
 }
 
 static int
-window_draw(struct widget *wp)
+window_draw(struct libwidget_state *lws, struct widget *wp)
 {
-    if (wp == NULL) {
+    struct fb_info *fbinfo;
+    struct blueprint *bp;
+    const struct bp_color *color;
+    uint32_t x, y, idx;
+
+    if (lws == NULL || wp == NULL) {
         return -EINVAL;
     }
 
+    bp = &wp->bp;
+    color = &bp->color;
+    fbinfo = &lws->fbinfo;
+
+    /* Draw a square */
+    for (uint32_t cy = 0; cy < bp->height; ++cy) {
+        for (uint32_t cx = 0; cx < bp->width; ++cx) {
+            x = bp->x + cx;
+            y = bp->y + cy;
+            idx = get_pix_index(&lws->fbinfo, x, y);
+            lws->fbdev[idx] = color->bg;
+        }
+    }
+
     return 0;
 }
 
diff --git a/src/lib/libwidget/src/core/widget_core.c b/src/lib/libwidget/src/core/widget_core.c
index 9501067..a217e87 100644
--- a/src/lib/libwidget/src/core/widget_core.c
+++ b/src/lib/libwidget/src/core/widget_core.c
@@ -32,25 +32,29 @@
 #include <stddef.h>
 #include <string.h>
 #include <sys/mac.h>
+#include <sys/fbdev.h>
 #include <libwidget/window.h>
 #include <libwidget/core.h>
 
 static struct widget backends[];
+static struct libwidget_state lws;
 
 /*
  * Initialize lib widget
  */
 int
-libwidget_init(struct libwidget_state *lwsp)
+libwidget_init(void)
 {
     int error;
 
-    if (lwsp == NULL) {
-        return -EINVAL;
+    /* Grab framebuffer information */
+    error = query(BORDER_FBDEV, &lws.fbinfo, sizeof(lws.fbinfo), 0);
+    if (error < 0) {
+        return error;
     }
 
     /* Grab the whole framebuffer, directly mapped */
-    error = cross(BORDER_FBDEV, -1, 0, 0, &lwsp->fbdev);
+    error = cross(BORDER_FBDEV, -1, 0, 0, &lws.fbdev);
     if (error < 0) {
         return error;
     }
@@ -109,7 +113,7 @@ widget_update(struct widget *wp)
     struct widget_ops *ops;
 
     ops = wp->ops;
-    return ops->draw(wp);
+    return ops->draw(&lws, wp);
 }
 
 static struct widget backends[] = {