Adapt exception messages

3 files changed, 31 insertions, 11 deletions

diff --git a/kernel/src/interrupts/exceptions.rs b/kernel/src/interrupts/exceptions.rs
index b6fb5a6..88c78a7 100644
--- a/kernel/src/interrupts/exceptions.rs
+++ b/kernel/src/interrupts/exceptions.rs
@@ -1,11 +1,19 @@
 use x86_64::structures::idt::{InterruptStackFrame, PageFaultErrorCode};
 
+macro_rules! exception_default {
+    ($stack_frame: expr) => {
+        format_args!("instruction addr: 0x{:08x}\nstack addr: 0x{:08x}\nflags: 0x{:x}",
+                    $stack_frame.instruction_pointer.as_u64(),
+                    $stack_frame.cpu_flags,
+                    $stack_frame.stack_pointer.as_u64()
+             )
+    }
+}
+
 pub extern "x86-interrupt" fn breakpoint_handler(stack_frame: &mut InterruptStackFrame) {
     panic!(
-        "BREAKPOINT at {:x} Flags: {:b} Stack: {:x}",
-        stack_frame.instruction_pointer.as_u64(),
-        stack_frame.cpu_flags,
-        stack_frame.stack_pointer.as_u64()
+        "BREAKPOINT exception thrown\n\n{}",
+        exception_default!(stack_frame)
     );
 }
 
@@ -16,11 +24,11 @@ pub extern "x86-interrupt" fn page_fault_handler(
     use x86_64::registers::control::Cr2;
 
     panic!(
-        "PAGE FAULT while accessing address: {:x}{:?}Flags: {:b} Stack: {:x}",
+        "PAGE FAULT while accessing address: 0x{:08x}\nerror code: {:?}(0x{:x})\n{}",
         Cr2::read().as_u64(),
         error_code,
-        stack_frame.cpu_flags,
-        stack_frame.stack_pointer.as_u64()
+        error_code.bits(),
+        exception_default!(stack_frame)
     );
 }
 
diff --git a/kernel/src/io/vga_text.rs b/kernel/src/io/vga_text.rs
index 833c191..277db73 100644
--- a/kernel/src/io/vga_text.rs
+++ b/kernel/src/io/vga_text.rs
@@ -160,10 +160,11 @@ impl OStream {
     pub fn print_centered(&mut self, s: &[u8]) {
         let mut line_start = 0;
         let mut line_len = 0;
-        for chunk in s.chunks(WIDTH) {
-            for line in chunk.split(|&c| c == b'\n') {
-                self.set_col((WIDTH - line.len()) >> 1);
-                self.put_bytes(line);
+        for line in s.split(|&c| c == b'\n') {
+            if line.is_empty() { self.new_line() }
+            for chunk in line.chunks(WIDTH) {
+                self.set_col((WIDTH - chunk.len()) >> 1);
+                self.put_bytes(chunk);
                 self.new_line()
             }
         }
diff --git a/kernel/src/lib.rs b/kernel/src/lib.rs
index d18ca6f..e18c22c 100644
--- a/kernel/src/lib.rs
+++ b/kernel/src/lib.rs
@@ -33,6 +33,17 @@ pub extern "C" fn _start() -> ! {
         test_main();
         qemu::exit_qemu(qemu::QemuExitCode::Success);
     }
+
+    fn _loop(i: u64) -> u64 {
+        if i > 0b1010101001101101 {
+             return i;
+        }
+        let n = i;
+        let mut stdout = OStream::new();
+        write!(&mut stdout, "{:x}", &n as *const u64 as u64).unwrap();
+        _loop(i + 1)
+    }
+    _loop(0);
     x86_64::instructions::interrupts::int3();
 
     let stdout = OStream::new();