From 07018064bbc27a4b8aad99832fbe3a0e608775d9 Mon Sep 17 00:00:00 2001
From: rsc <rsc>
Date: Wed, 8 Aug 2007 08:04:02 +0000
Subject: [PATCH] add EOF handling to console_read - works with cat
---
console.c | 31 ++++++++++++++++++-------------
1 file changed, 18 insertions(+), 13 deletions(-)
diff --git a/console.c b/console.c
index 449c03f..00aa775 100644
--- a/console.c
+++ b/console.c
@@ -316,7 +316,7 @@ static uchar *charcode[4] = {
};
#define KBD_BUF 64
-char kbd_buf[KBD_BUF];
+uchar kbd_buf[KBD_BUF];
int kbd_r;
int kbd_w;
struct spinlock kbd_lock;
@@ -389,24 +389,29 @@ out:
int
console_read(int minor, char *dst, int n)
{
- uint target = n;
+ uint target;
+ int c;
+ target = n;
acquire(&kbd_lock);
-
- while(kbd_w == kbd_r) {
- sleep(&kbd_r, &kbd_lock);
- }
-
- while(n > 0 && kbd_w != kbd_r){
- *dst = (kbd_buf[kbd_r]) & 0xff;
- cons_putc(*dst & 0xff);
- dst++;
+ while(n > 0){
+ while(kbd_r == kbd_w)
+ sleep(&kbd_r, &kbd_lock);
+ c = kbd_buf[kbd_r++];
+ if(c == C('D')){ // EOF
+ if(n < target){
+ // Save ^D for next time, to make sure
+ // caller gets a 0-byte result.
+ kbd_r--;
+ }
+ break;
+ }
+ *dst++ = c;
+ cons_putc(c);
--n;
- kbd_r++;
if(kbd_r >= KBD_BUF)
kbd_r = 0;
}
-
release(&kbd_lock);
return target - n;