usr/src/psm/promif/ieee1275/common/prom_getchar.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License, Version 1.0 only
   6  * (the "License").  You may not use this file except in compliance
   7  * with the License.
   8  *
   9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
  10  * or http://www.opensolaris.org/os/licensing.
  11  * See the License for the specific language governing permissions
  12  * and limitations under the License.
  13  *
  14  * When distributing Covered Code, include this CDDL HEADER in each
  15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  16  * If applicable, add the following below this CDDL HEADER, with the
  17  * fields enclosed by brackets "[]" replaced with your own identifying
  18  * information: Portions Copyright [yyyy] [name of copyright owner]
  19  *
  20  * CDDL HEADER END
  21  */
  22 /*
  23  * Copyright (c) 1991-1994, by Sun Microsystems, Inc.
  24  * All rights reserved.
  25  */
  26
  27 #pragma ident   "%Z%%M% %I%     %E% SMI"
  28
  29 #include <sys/promif.h>
  30 #include <sys/promimpl.h>
  31
  32 u_char
  33 prom_getchar(void)
  34 {
  35         int c;
  36
  37         while ((c = prom_mayget()) == -1)
  38                 ;
  39
  40         return ((u_char)c);
  41 }
  42
  43 int
  44 prom_mayget(void)
  45 {
  46         ssize_t rv;
  47         char c;
  48
  49         rv = prom_read(prom_stdin_ihandle(), &c, 1, 0, BYTE);
  50         return (rv == 1 ? (int)c : -1);
  51 }