1 files changed, 87 insertions, 0 deletions
diff --git a/src/fb.c b/src/fb.c
new file mode 100644
index 0000000..7e5bf1f
--- /dev/null
+++ b/src/fb.c
@@ -0,0 +1,87 @@
+#include "fb.h"
+#include <memory.h>
+
+volatile static fb_t *current, *head, *tail;
+
+static void fb_add(fb_t *new, fb_t *prev, fb_t *next)
+{
+	next->prev = new;
+	new->next = next;
+	new->prev = prev;
+	prev->next = new;
+}
+
+fb_t *fblist_insert(fb_t *at, fb_t *new) 
+{
+	fb_add(new, at, at->next);
+	return new;
+}
+
+fb_t *fblist_append(fb_t *new) 
+{
+	fblist_insert(new, tail);
+	tail = new;
+	return new;
+}
+
+fb_t *fblist_gonext() 
+{
+	current = current->next;
+	current->scroll = 0;
+	return current;
+}
+
+fb_t *fblist_goprev() 
+{
+	current = current->prev;
+	current->scroll = 0;
+	return current;
+}
+
+fb_t *fblist_gohead()
+{
+	current = head;
+	current->scroll = 0;
+	return current;
+}
+
+fb_t *fblist_currentfb()
+{
+	return current;
+}
+
+static void list_del(fb_t *prev, fb_t *next)
+{
+	prev->next = next;
+	next->prev = prev;
+}
+
+fb_t *fblist_drop(fb_t *fb)
+{
+	list_del(fb->prev, fb->next);
+	return fb->next;
+}
+
+fb_t *fb_new(uint16_t width)
+{
+	fb_t *fb = malloc(sizeof(fb_t));
+	memset(fb, 0, sizeof(fb_t));
+
+	fb->width = width;
+	fb->buf = malloc(width * sizeof(uint16_t));
+	memset(fb->buf, 0, width * sizeof(uint16_t));
+
+	fb->modes = FIXED;
+
+	fb->next = fb;
+	fb->prev = fb;
+
+	return fb;
+}
+
+void fblist_init(uint16_t first_fb_width)
+{
+	current = fb_new(first_fb_width);
+	head = current;
+	tail = current;
+}