xous-log: stdout: insert \r when printing \n

When printing messages to stdout or stderr, insert `\r` whenever we
encounter `\n`.

Signed-off-by: Sean Cross <[email protected]>

services/xous-log/src/main.rs

@@ -12,32 +12,36 @@ use num_traits::FromPrimitive;
 use platform::implementation;
 
 /// A page-aligned stack allocation for connection requests (used by USB resolver)
-#[cfg(feature="usb")]
+#[cfg(feature = "usb")]
 #[repr(C, align(4096))]
 struct ConnectRequest {
     name: [u8; 64],
     len: u32,
     _padding: [u8; 4096 - 4 - 64],
 }
-#[cfg(feature="usb")]
+#[cfg(feature = "usb")]
 impl Default for ConnectRequest {
     fn default() -> Self {
-        ConnectRequest { name: [0u8; 64], len: 0, _padding: [0u8; 4096 - 4 - 64] }
+        ConnectRequest {
+            name: [0u8; 64],
+            len: 0,
+            _padding: [0u8; 4096 - 4 - 64],
+        }
     }
 }
 
-#[cfg(feature="usb")]
+#[cfg(feature = "usb")]
 #[derive(Debug, rkyv::Archive, rkyv::Serialize, rkyv::Deserialize, Copy, Clone)]
 pub struct UsbString {
-    pub s: xous_ipc::String::<4000>,
+    pub s: xous_ipc::String<4000>,
     pub sent: Option<u32>,
 }
 
-#[cfg(feature="usb")]
+#[cfg(feature = "usb")]
 fn usb_send_str(conn: xous::CID, s: &str) {
     let serializer = UsbString {
         s: xous_ipc::String::<4000>::from_str(s),
-        sent: None
+        sent: None,
     };
     let buf = xous_ipc::Buffer::into_buf(serializer).expect("usb error");
     // failures to send are silent & ignored; also, this API doesn't block.
@@ -49,10 +53,10 @@ fn reader_thread(arg: usize) {
     writeln!(output, "LOG: Xous Logging Server starting up...").ok();
     let server_addr = xous::create_server_with_address(b"xous-log-server ").expect("create server");
     writeln!(output, "LOG: Server listening on address {:?}", server_addr).ok();
-    #[cfg(feature="usb")]
+    #[cfg(feature = "usb")]
     let mut usb_serial: Option<xous::CID> = None;
     // use a stack-allocated string to ensure no heap thrashing results from String manipulations
-    #[cfg(feature="usb")]
+    #[cfg(feature = "usb")]
     let mut usb_str = xous_ipc::String::<4000>::new();
 
     println!("LOG: my PID is {}", xous::process::id());
@@ -118,9 +122,10 @@ fn reader_thread(arg: usize) {
                             write!(output, ":{}", line.get()).ok();
                         }
                         writeln!(output, ")").ok();
-                        #[cfg(feature="usb")]
+                        #[cfg(feature = "usb")]
                         if let Some(conn) = usb_serial {
-                            if usb_str.len() > 0 { // test length so we aren't constantly copying 4096 bytes of 0's clearing an already cleared structure.
+                            if usb_str.len() > 0 {
+                                // test length so we aren't constantly copying 4096 bytes of 0's clearing an already cleared structure.
                                 usb_str.clear();
                             }
                             // duplicate the above code because doing repeated calls to the USB stack is inefficient
@@ -165,10 +170,15 @@ fn reader_thread(arg: usize) {
                                 buffer_length,
                             )
                         };
-                        output.write_all(buffer).unwrap();
+                        for c in buffer {
+                            if *c == b'\n' {
+                                output.putc(b'\r');
+                            }
+                            output.putc(*c);
+                        }
                         // TODO: If the buffer is mutable, set `length` to 0.
 
-                        #[cfg(feature="usb")]
+                        #[cfg(feature = "usb")]
                         if let Some(conn) = usb_serial {
                             // safety: this routine will just blow up if you try to pass non utf-8 to it,
                             // so it's not very safe. On the other hand, it's fast and shame on you for sending