Make a new layout for the OS, rebrand to XunilOS

kernel/src/driver/framebuffer.rs

@@ -0,0 +1,53 @@
+use limine::framebuffer::Framebuffer as LimineFramebuffer;
+
+const MAX_BACKBUFFER_PIXELS: usize = 1920 * 1080;
+static mut BACK_BUFFER: [u32; MAX_BACKBUFFER_PIXELS] = [0; MAX_BACKBUFFER_PIXELS];
+
+pub struct Framebuffer {
+    addr: *mut u32,
+    back_buffer: *mut u32,
+    width: usize,
+    height: usize,
+    pitch: usize,
+    back_buffer_len: usize,
+}
+
+impl Framebuffer {
+    pub fn new(limine_fb: &LimineFramebuffer) -> Framebuffer {
+        let width = limine_fb.width() as usize;
+        let height = limine_fb.height() as usize;
+        let pitch = limine_fb.pitch() as usize / 4;
+        let needed = pitch.saturating_mul(height);
+        let back_buffer_len = core::cmp::min(needed, MAX_BACKBUFFER_PIXELS);
+
+        Framebuffer {
+            addr: limine_fb.addr().cast::<u32>(),
+            back_buffer: core::ptr::addr_of_mut!(BACK_BUFFER).cast::<u32>(),
+            width,
+            height,
+            pitch,
+            back_buffer_len,
+        }
+    }
+
+    pub fn put_pixel(&mut self, x: usize, y: usize, color: u32) {
+        if x >= self.width || y >= self.height {
+            return;
+        }
+
+        let idx = y.saturating_mul(self.pitch).saturating_add(x);
+        if idx >= self.back_buffer_len {
+            return;
+        }
+
+        unsafe {
+            *self.back_buffer.add(idx) = color;
+        }
+    }
+
+    pub fn swap(&mut self) {
+        unsafe {
+            core::ptr::copy_nonoverlapping(self.back_buffer, self.addr, self.back_buffer_len);
+        }
+    }
+}