[chg] rewrite current line with timestamp prefix after newline

timestamp marks the time when the line was "sent" or "committed"

src/main.rs

@@ -1,49 +1,65 @@
-use std::io::{Write, Read, ErrorKind, stdin, stdout};
 use chrono::prelude::*;
-
+use std::io::{stdin, stdout, ErrorKind, Read, StdoutLock, Write};
 
 #[inline(always)]
-fn print_time() {
+fn print_time(output: &mut StdoutLock) -> Result<(), std::io::Error> {
     let date_now = Local::now().format("%H:%M:%S%.9f");
 
     let color_green = "\x1b\x5b\x30\x3b\x33\x32\x6d";
     let color_off = "\x1b\x5b\x30\x6d";
 
-    print!("{}[{}]{} ", color_green, &date_now, color_off);
+    write!(output, "{}[{}]{} ", color_green, &date_now, color_off)
 }
 
+#[inline(always)]
+fn print_delete_line(output: &mut StdoutLock) -> Result<(), std::io::Error> {
+    // tput dl1 und tput hpa 0
+    let bytes = "\x1b\x5b\x4d\x1b\x5b\x31\x47";
+    write!(output, "{}", bytes)
+}
 
-fn main() {
+fn run() -> Result<(), std::io::Error> {
     let out = stdout();
     let mut output = out.lock();
 
     let inp = stdin();
     let mut input = inp.lock();
 
+    let mut buf = [0; 1];
+
+    let mut linebuf = Vec::with_capacity(64 * 1024);
 
-    print_time();
     loop {
-        let mut buf = [0; 1];
-
-        let _ = input.read_exact(&mut buf).map_err(|e| {
-
-            if e.kind() != ErrorKind::UnexpectedEof {
-                println!("{}", e.to_string());
-                std::process::exit(1);
+        if let Err(e) = input.read_exact(&mut buf) {
+            if e.kind() == ErrorKind::UnexpectedEof {
+                return Err(e);
+            } else {
+                output.flush()?;
+                return Ok(());
             }
+        }
 
-            let _ = output.flush();
-            std::process::exit(0);
-        });
-
+        linebuf.push(buf[0]);
 
         if buf[0] == 0xa {
-            print!("\n");
-            print_time();
+            print_delete_line(&mut output)?;
+            print_time(&mut output)?;
+            output.write_all(&linebuf)?;
+
+            output.flush()?;
+
+            linebuf.clear();
             continue;
         }
 
-        let _ = output.write_all(&mut buf);
-        let _ = output.flush();
+        output.write_all(&buf)?;
+        output.flush()?;
+    }
+}
+
+fn main() {
+    if let Err(e) = run() {
+        println!("{:?}", e);
+        std::process::exit(1);
     }
 }