Create panic screen module with text buffer

1 files changed, 10 insertions, 24 deletions

diff --git a/kernel/src/io/vga_text.rs b/kernel/src/io/vga_text.rs
index 281a40a..eef56bf 100644
--- a/kernel/src/io/vga_text.rs
+++ b/kernel/src/io/vga_text.rs
@@ -103,7 +103,7 @@ impl OStream {
     pub fn put_char(&mut self, c: VgaChar) {
         if c.byte == b'\n' {
             self.new_line();
-        } else if self.pos.0 >= WIDTH - 1 {
+        } else if self.pos.0 >= WIDTH {
             self.new_line();
             self.put_char(c);
         } else {
@@ -158,31 +158,17 @@ impl OStream {
     }
 
     pub fn print_centered(&mut self, s: &[u8]) {
-        let mut line = &s[..];
-        let mut n = 0;
-        if s.len() == 0 { return; }
-        let slast = s.len() - 1;
-        for (i, &b) in s.iter().enumerate() {
-            if n >= WIDTH {
-                self.set_col(0);
-                self.put_bytes(&line[..WIDTH]);
-                line = &line[WIDTH..];
-                n = 0;
-            }
-            if b == b'\n' || i == slast {
-                if b != b'\n' {
-                    n += 1
-                }
-                self.set_col(((WIDTH - n) / 2) as usize);
-                self.put_bytes(&line[..n]);
+        let mut line_start = 0;
+        let mut line_len = 0;
+        for (n, &c) in s.iter().enumerate() {
+            if line_len >= WIDTH || c == b'\n' || n == s.len() - 1 {
+                self.set_col((WIDTH - line_len) >> 1);
+                self.put_bytes(&s[line_start..(line_start+line_len+1)]);
                 self.new_line();
-                if i == slast {
-                    return;
-                }
-                line = &line[(n + 1)..];
-                n = 0;
+                line_start += line_len;
+                line_len = 0;
             }
-            n += 1;
+            line_len += 1;
         }
     }
 }