Defined EOF as -1 in stdio.h.

Implemented the sprintf() library function in lib/stdio.c which uses the
vsprintf() function.

Implemented a very primative controlling TTY for each process. This is
achieved by a switch in the sys_puts system call which uses the 'ctty'
element of the process' task structure to determine an appropriate I/O
channel. A negative ctty value doesn't equate to any I/O channel
effectively disabling the process' output.

Added the sys_ctty system call which allows a process to set it's own
ctty value.

Removed the sys_rsputs system call. Output to serial is now performed by
the process first setting it's ctty value to 1, then invoking sys_puts.

1 files changed, 13 insertions, 7 deletions

diff --git a/kernel/serial.c b/kernel/serial.c
index 7f23298..86bbd87 100644
--- a/kernel/serial.c
+++ b/kernel/serial.c
@@ -15,10 +15,20 @@
 #define RSMODEMS  (RSBASE + 6)
 #define RSSCRATCH (RSBASE + 7)
 
-static int rsputs(char *s) {
+#define rswait()\
+  while((inb(RSLINES) & 0x20) == 0);
+
+int rsputs(char *s) {
   while(*s) {
-    while((inb(RSLINES) & 0x20) == 0);
-    outb(RSDATA, *s++);
+    rswait();
+    if(*s == '\n') {
+      outb(RSDATA, '\n');
+      rswait();
+      outb(RSDATA, '\r');
+      s++;
+    } else {
+      outb(RSDATA, *s++);
+    }
   }
 
   return 0;
@@ -46,7 +56,3 @@ void serial_init(void) {
   rsputs("[kernel] Serial monitor initialized!\n\r");
   printk("[rs] Serial port COM0 initialized!\n");
 }
-
-int sys_rsputs(char *s) {
-  return rsputs(s);
-}