update v2

kernel/src/console.rs

@@ -0,0 +1,130 @@
+//! Simple VGA console for AIOS v2
+//! No external crates, pure Rust implementation
+
+use core::fmt::{self, Write};
+
+const VGA_BUFFER: *mut u16 = 0xb8000 as *mut u16;
+const VGA_WIDTH: usize = 80;
+const VGA_HEIGHT: usize = 25;
+
+static mut CONSOLE: Console = Console {
+    col: 0,
+    row: 0,
+    color: 0x0f, // White on black
+};
+
+struct Console {
+    col: usize,
+    row: usize,
+    color: u8,
+}
+
+impl Console {
+    fn clear(&mut self) {
+        for i in 0..(VGA_WIDTH * VGA_HEIGHT) {
+            unsafe {
+                VGA_BUFFER.add(i).write_volatile(0x0f00); // Clear with white on black
+            }
+        }
+        self.col = 0;
+        self.row = 0;
+    }
+    
+    fn write_byte(&mut self, byte: u8) {
+        match byte {
+            b'\n' => {
+                self.col = 0;
+                self.row += 1;
+                if self.row >= VGA_HEIGHT {
+                    self.scroll_up();
+                }
+            }
+            byte => {
+                if self.col >= VGA_WIDTH {
+                    self.col = 0;
+                    self.row += 1;
+                    if self.row >= VGA_HEIGHT {
+                        self.scroll_up();
+                    }
+                }
+                
+                let pos = self.row * VGA_WIDTH + self.col;
+                let entry = (self.color as u16) << 8 | byte as u16;
+                
+                unsafe {
+                    VGA_BUFFER.add(pos).write_volatile(entry);
+                }
+                
+                self.col += 1;
+            }
+        }
+    }
+    
+    fn scroll_up(&mut self) {
+        // Move all lines up by one
+        for row in 1..VGA_HEIGHT {
+            for col in 0..VGA_WIDTH {
+                let pos = row * VGA_WIDTH + col;
+                let prev_pos = (row - 1) * VGA_WIDTH + col;
+                unsafe {
+                    let entry = VGA_BUFFER.add(pos).read_volatile();
+                    VGA_BUFFER.add(prev_pos).write_volatile(entry);
+                }
+            }
+        }
+        
+        // Clear last line
+        for col in 0..VGA_WIDTH {
+            let pos = (VGA_HEIGHT - 1) * VGA_WIDTH + col;
+            unsafe {
+                VGA_BUFFER.add(pos).write_volatile(0x0f00);
+            }
+        }
+        
+        self.row = VGA_HEIGHT - 1;
+    }
+}
+
+impl Write for Console {
+    fn write_str(&mut self, s: &str) -> fmt::Result {
+        for byte in s.bytes() {
+            self.write_byte(byte);
+        }
+        Ok(())
+    }
+}
+
+pub fn init() {
+    unsafe {
+        CONSOLE.clear();
+    }
+}
+
+pub fn print(s: &str) {
+    unsafe {
+        CONSOLE.write_str(s).unwrap();
+    }
+}
+
+#[macro_export]
+macro_rules! kprint {
+    ($($arg:tt)*) => {
+        $crate::console::_print(format_args!($($arg)*))
+    };
+}
+
+#[macro_export]
+macro_rules! kprintln {
+    () => ($crate::console::print("\n"));
+    ($($arg:tt)*) => ({
+        $crate::console::_print(format_args!($($arg)*));
+        $crate::console::print("\n");
+    })
+}
+
+#[doc(hidden)]
+pub fn _print(args: fmt::Arguments) {
+    unsafe {
+        CONSOLE.write_fmt(args).unwrap();
+    }
+}