1 /*
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright © 2020 Keith Packard
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  *
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  *
13  * 2. Redistributions in binary form must reproduce the above
14  *    copyright notice, this list of conditions and the following
15  *    disclaimer in the documentation and/or other materials provided
16  *    with the distribution.
17  *
18  * 3. Neither the name of the copyright holder nor the names of its
19  *    contributors may be used to endorse or promote products derived
20  *    from this software without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
23  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
24  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
25  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
26  * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
27  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
28  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
29  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
31  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
32  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
33  * OF THE POSSIBILITY OF SUCH DAMAGE.
34  */
35 
36 #include "semihost-private.h"
37 #include <sys/types.h>
38 #include <sys/stat.h>
39 #include <fcntl.h>
40 #include <unistd.h>
41 #include <string.h>
42 #include <errno.h>
43 #include <stdbool.h>
44 
45 static int fd_stdin, fd_stdout, fd_stderr;
46 static bool _check_done;
47 
48 int
_map_stdio(int fd)49 _map_stdio(int fd)
50 {
51 	if (!_check_done) {
52 		_check_done = true;
53 		fd_stdin = sys_semihost_open(":tt", 0);
54 		fd_stdout = sys_semihost_open(":tt", 4);
55 		fd_stderr = sys_semihost_open(":tt", 8);
56 	}
57 	switch (fd) {
58 	case 0:
59 		return fd_stdin;
60 	case 1:
61 		return fd_stdout;
62 	case 2:
63 		return fd_stderr;
64 	default:
65 		return fd;
66 	}
67 }
68