Tests

src/lib.rs

@@ -0,0 +1,69 @@
+#![no_std]
+#![cfg_attr(test, no_main)]
+#![feature(custom_test_frameworks)]
+#![test_runner(crate::test_runner)]
+#![reexport_test_harness_main = "test_main"]
+
+use core::panic::PanicInfo;
+pub mod serial;
+pub mod vga_buffer;
+
+pub trait Testable {
+    fn run(&self) -> ();
+}
+
+impl<T> Testable for T
+where
+    T: Fn(),
+{
+    fn run(&self) {
+        serial_print!("{}...\t", core::any::type_name::<T>());  // 打印函数名
+        self();     // 执行这个函数。由于 T 具有 Fn() trait 所以它能够作为一个函数被直接调用
+        serial_println!("[ok]");    // 打印 "[ok]"
+    }
+}
+
+pub fn test_runner(tests: &[&dyn Testable]) {
+    serial_println!("Running {} tests", tests.len());
+    for test in tests {
+        test.run();
+    }
+    exit_qemu(QemuExitCode::Success);
+}
+
+pub fn test_panic_handler(info: &PanicInfo) -> ! {
+    serial_println!("[failed]\n");
+    serial_println!("Error: {}\n", info);
+    exit_qemu(QemuExitCode::Failed);
+    loop {}
+}
+
+#[cfg(test)]
+#[no_mangle]
+pub extern "C" fn _start() -> ! {
+    test_main();
+    loop {}
+}
+
+#[cfg(test)]
+#[panic_handler]
+fn panic(info: &PanicInfo) -> ! {
+    test_panic_handler(info)
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+#[repr(u32)]
+pub enum QemuExitCode {
+    Success = 0x10,
+    Failed = 0x11,
+}
+
+pub fn exit_qemu(exit_code: QemuExitCode) {
+    use x86_64::instructions::port::Port;
+
+    unsafe {
+        let mut port = Port::new(0xf4);     // iobase port
+        port.write(exit_code as u32);
+    }
+}
+

src/main.rs

@@ -1,12 +1,11 @@
 #![no_std]      // 不链接 Rust 标准库
 #![no_main]     // 禁用 main 入口点，因为没有运行时
+#![feature(custom_test_frameworks)]
+#![test_runner(anos::test_runner)]
+#![reexport_test_harness_main = "test_main"]
 
 use core::panic::PanicInfo;
-
-mod vga_buffer;
-
-// 定义一个 byte string 类型的静态变量
-static HELLO: &[u8] = b"Hello World!";
+use anos::println;
 
 #[no_mangle]    // 不重整函数名，否则编译器可能会生成名为 _ZN3blog_os4_start7hb173fedf945531caE 的函数
 // extern "C" 告诉编译器这个函数应当使用 C 语言的调用约定
@@ -15,9 +14,14 @@ static HELLO: &[u8] = b"Hello World!";
 pub extern "C" fn _start() -> ! {
     println!("Hello World{}", "!");
 
+    #[cfg(test)]
+    test_main();
+
     loop {}
 }
 
+// 在非测试模式下，将 panic 信息打印到 VGA 缓冲区
+#[cfg(not(test))]
 #[panic_handler]
 // panic! 时将会进行栈展开，执行各种 drop 函数来回收垃圾
 // 禁用标准库之后，这些东西就都没有了，我们需要把它重写一遍
@@ -25,3 +29,9 @@ fn panic(info: &PanicInfo) -> ! {
     println!("{}", info);
     loop {}
 }
+
+#[cfg(test)]
+#[panic_handler]
+fn panic(info: &PanicInfo) -> ! {
+    anos::test_panic_handler(info)
+}

src/serial.rs

@@ -0,0 +1,32 @@
+use uart_16550::SerialPort;
+use spin::Mutex;
+use lazy_static::lazy_static;
+
+lazy_static! {
+    pub static ref SERIAL1: Mutex<SerialPort> = {
+        let mut serial_port = unsafe { SerialPort::new(0x3F8) };
+        serial_port.init();
+        Mutex::new(serial_port)
+    };
+}
+
+#[doc(hidden)]
+pub fn _print(args: ::core::fmt::Arguments) {
+    use core::fmt::Write;
+    SERIAL1.lock().write_fmt(args).expect("Printing to serial failed");
+}
+
+#[macro_export]
+macro_rules! serial_print {
+    ($($arg:tt)*) => {
+        $crate::serial::_print(format_args!($($arg)*));
+    };
+}
+
+#[macro_export]
+macro_rules! serial_println {
+    () => ($crate::serial_print!("\n"));
+    ($fmt:expr) => ($crate::serial_print!(concat!($fmt, "\n")));
+    ($fmt:expr, $($arg:tt)*) => ($crate::serial_print!(
+        concat!($fmt, "\n"), $($arg)*));
+}

src/vga_buffer.rs

@@ -125,38 +125,25 @@ impl fmt::Write for Writer {
     }
 }
 
-lazy_static! {
-    pub static ref WRITER: Mutex<Writer> = Mutex::new(Writer {
+// 将 Writer 设置为静态以便调用
+lazy_static! {  // 内置的 static 会用到标准库里的一些东西，所以这里用 lazy_static
+    pub static ref WRITER: Mutex<Writer> = Mutex::new(Writer {  // 用互斥锁来防止冲突
         column_position: 0,
         color_code: ColorCode::new(Color::Yellow, Color::Black),
         buffer: unsafe { &mut *(0xb8000 as *mut Buffer) }
     });
 }
 
-pub fn print_something() {
-    use core::fmt::Write;
-    let mut writer = Writer {
-        column_position: 0,
-        color_code: ColorCode::new(Color::Yellow, Color::Black),
-        // VGA Buffer 从 0xb8000 开始
-        buffer: unsafe { &mut *(0xb8000 as *mut Buffer) },
-    };
-    writer.write_byte(b'H');
-    writer.write_string("ello ");
-    writer.write_string("Wörld!");
-    write!(writer, "The numbers are {} and {}", 42, 1.0/3.0).unwrap();
-}
-
 // 将宏导出到 crate 的根，这样我们就可以用
 // use crate::println
 // 来使用它
 #[macro_export]
-macro_rules! print {
+macro_rules! print {    // print!()
     ($($arg:tt)*) => ($crate::vga_buffer::_print(format_args!($($arg)*)));
 }
 
 #[macro_export]
-macro_rules! println {
+macro_rules! println {  // println!()
     () => ($crate::print!("\n"));
     ($($arg:tt)*) => ($crate::print!("{}\n", format_args!($($arg)*)));
 }
@@ -168,3 +155,25 @@ pub fn _print(args: fmt::Arguments) {
     use core::fmt::Write;
     WRITER.lock().write_fmt(args).unwrap();
 }
+
+#[test_case]
+fn test_println_simple() {  // 测试单行 println!
+    println!("test_println_simple output");
+}
+
+#[test_case]
+fn test_println_many() {    // 测试多行 println!
+    for _ in 0..100 {
+        println!("test_println_many output");
+    }
+}
+
+#[test_case]
+fn test_println_output() {  // 测试字符是否真的打印到了屏幕上
+    let s = "Some test string that fits on a single line";
+    println!("{}", s);
+    for (i, c) in s.chars().enumerate() {
+        let screen_char = WRITER.lock().buffer.chars[BUFFER_HEIGHT - 2][i].read();
+        assert_eq!(char::from(screen_char.ascii_character), c);
+    }
+}