Add exit on enter press

wtfstopw.asm

 mov rdx, rcx
 syscall
 
-sleep:
-mov rax, 35
-mov rdi, ts_sleep
-mov rsi, 0
+; Attempt to read from stdin
+; if something read, enter has been pressed
+mov rax, 0
+mov rdi, 0
+mov rsi, buf
+mov rdx, 1
 syscall
-jmp print_time
+cmp rax, 0
+jge flush_stdin ; flush stdin and exit
+
+sleep:
+	mov rax, 35
+	mov rdi, ts_sleep
+	mov rsi, 0
+	syscall
+
+jmp print_time ; main loop
+
+flush_stdin:
+	mov rax, 0
+	mov rdi, 0
+	mov rsi, buf
+	mov rdx, 1
+	syscall
+	cmp rax, 0
+	je newline
+	jg flush_stdin
 
 exit:
 	mov rax, 60 ; sys_exit
 	mov rdi, 1 ; failure
 	syscall
 
-
-dumprax:
-	push rax
-	loopdump:
-		push rax
-		mov rbx, rax
-		and rbx, 0x0F
-		cmp bl, 0xA
-		jge hexdigit
-		add bl, 0x30
-		jmp loopcont
-		hexdigit:
-		sub bl, 10
-		add bl, 0x41
-		loopcont:
-dbg:
-		mov byte [digit], bl
-		mov rax, 1
-		mov rdi, 1
-		mov rsi, digit
-		mov rdx, 1
-		syscall
-	pop rax
-	mov rdi, 10
-	xor rdx, rdx
-	mov rsi, rax
-	div rdi
-	cmp rax, 10
-	jge loopdump
-
-	mov al, 10
-	mov al, [digit]
+newline:
 	mov rax, 1
 	mov rdi, 1
 	mov rsi, nl
 	mov rdx, 1
 	syscall
+	jmp exit
 
-	pop rax
-ret
 
 section .data
-foobar: ISTRUC timespec
+
 ts_start:
 	tv_start_s dq 0
 	tv_start_us dq 0
 msglen: equ $ - msg
 
 hours: db "000000000"
-timestr: db ":00:00.0000", 0x0D
+timestr: db ":00:00.0000    ", 0x0D
 timestrlen: equ $ - timestr
 
-digit: db "0"
 nl: db 10
+buf: db 0
 
 ts_cur:
 	tv_cur_s dq 0