2 * ARM Compatible Semihosting Console Support.
4 * Copyright (c) 2019 Linaro Ltd
6 * Currently ARM and RISC-V are unique in having support for
7 * semihosting support in linux-user. So for now we implement the
8 * common console API but just for arm and risc-v linux-user.
10 * SPDX-License-Identifier: GPL-2.0-or-later
13 #include "qemu/osdep.h"
14 #include "semihosting/console.h"
16 #include "user-internals.h"
20 * For linux-user we can safely block. However as we want to return as
21 * soon as a character is read we need to tweak the termio to disable
22 * line buffering. We restore the old mode afterwards in case the
23 * program is expecting more normal behaviour. This is slow but
24 * nothing using semihosting console reading is expecting to be fast.
26 int qemu_semihosting_console_read(CPUState *cs, void *buf, int len)
29 struct termios old_tio, new_tio;
31 /* Disable line-buffering and echo */
32 tcgetattr(STDIN_FILENO, &old_tio);
34 new_tio.c_lflag &= (~ICANON & ~ECHO);
35 new_tio.c_cc[VMIN] = 1;
36 new_tio.c_cc[VTIME] = 0;
37 tcsetattr(STDIN_FILENO, TCSANOW, &new_tio);
39 ret = fread(buf, 1, len, stdin);
42 tcsetattr(STDIN_FILENO, TCSANOW, &old_tio);
47 int qemu_semihosting_console_write(void *buf, int len)
49 return fwrite(buf, 1, len, stderr);