--- a/src/console.c	Mon Dec 17 16:55:22 2018 +0900
+++ b/src/console.c	Thu Jan 17 19:11:19 2019 +0900
@@ -215,6 +215,72 @@
     release(&input.lock);
 }
 
+__code cbc_consoleread (struct inode *ip, char *dst, int n, __code(*next)(int ret))
+{
+    uint target;
+    int c;
+
+    iunlock(ip);
+
+    target = n;
+    acquire(&input.lock);
+
+    while (n > 0) {
+        while (input.r == input.w) {
+            if (proc->killed) {
+                release(&input.lock);
+                ilock(ip);
+                goto next(-1);
+            }
+
+            proc->cbc_arg.cbc_console_arg.n = n;
+	    proc->cbc_arg.cbc_console_arg.dst = dst;
+	    proc->cbc_arg.cbc_console_arg.ip = ip;
+	    proc->cbc_arg.cbc_console_arg.next = next;
+            goto cbc_sleep(&input.r, &input.lock, cbc_consoleread1);
+        }
+}
+
+__code cbc_consoleread1 (__code(*next)(int ret))
+{
+    int cont = 1;
+    proc->cbc_arg.cbc_console_arg.n = n;
+    proc->cbc_arg.cbc_console_arg.dst = dst;
+    proc->cbc_arg.cbc_console_arg.ip = ip;
+    
+    c = input.buf[input.r++ % INPUT_BUF];
+
+        if (c == C('D')) {  // EOF
+            if (n < target) {
+                // Save ^D for next time, to make sure
+                // caller gets a 0-byte result.
+                input.r--;  
+            }
+            cont = 0;
+       }
+
+        *dst++ = c;
+        --n;
+
+        if (c == '\n') {
+            cont = 0;
+        }
+    
+
+    if (cont){
+        proc->cbc_arg.cbc_console_arg.n = n;
+        proc->cbc_arg.cbc_console_arg.dst = dst;
+        proc->cbc_arg.cbc_console_arg.ip = ip;
+	proc->cbc_arg.cbc_console_arg.next = next;
+        goto cbc_sleep(&input.r, &input.lock, cbc_consoleread1);
+    }
+    
+    release(&input.lock);
+    ilock(ip);
+
+    goto next(target - n);
+}
+
 int consoleread (struct inode *ip, char *dst, int n)
 {
     uint target;
@@ -288,6 +354,8 @@
 
     devsw[CONSOLE].write = consolewrite;
     devsw[CONSOLE].read = consoleread;
+    cbc_devsw[CONSOLE].write = cbc_consolewrite;
+    cbc_devsw[CONSOLE].read = cbc_consoleread;
 
     cons.locking = 1;
 }