chardev/char-stdio.c

   1 /*
   2  * QEMU System Emulator
   3  *
   4  * Copyright (c) 2003-2008 Fabrice Bellard
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a copy
   7  * of this software and associated documentation files (the "Software"), to deal
   8  * in the Software without restriction, including without limitation the rights
   9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  10  * copies of the Software, and to permit persons to whom the Software is
  11  * furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice shall be included in
  14  * all copies or substantial portions of the Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  22  * THE SOFTWARE.
  23  */
  24
  25 #include "qemu/osdep.h"
  26 #include "qemu/module.h"
  27 #include "qemu/option.h"
  28 #include "qemu/sockets.h"
  29 #include "qapi/error.h"
  30 #include "chardev/char.h"
  31
  32 #ifdef _WIN32
  33 #include "chardev/char-win.h"
  34 #include "chardev/char-win-stdio.h"
  35 #else
  36 #include <termios.h>
  37 #include "chardev/char-fd.h"
  38 #endif
  39
  40 #ifndef _WIN32
  41 /* init terminal so that we can grab keys */
  42 static struct termios oldtty;
  43 static int old_fd0_flags;
  44 static int old_fd1_flags;
  45 static bool stdio_in_use;
  46 static bool stdio_allow_signal;
  47 static bool stdio_echo_state;
  48
  49 static void term_exit(void)
  50 {
  51     if (stdio_in_use) {
  52         tcsetattr(0, TCSANOW, &oldtty);
  53         fcntl(0, F_SETFL, old_fd0_flags);
  54         fcntl(1, F_SETFL, old_fd1_flags);
  55         stdio_in_use = false;
  56     }
  57 }
  58
  59 static void qemu_chr_set_echo_stdio(Chardev *chr, bool echo)
  60 {
  61     struct termios tty;
  62
  63     stdio_echo_state = echo;
  64     tty = oldtty;
  65     if (!echo) {
  66         tty.c_iflag &= ~(IGNBRK | BRKINT | PARMRK | ISTRIP
  67                          | INLCR | IGNCR | ICRNL | IXON);
  68         tty.c_oflag |= OPOST;
  69         tty.c_lflag &= ~(ECHO | ECHONL | ICANON | IEXTEN);
  70         tty.c_cflag &= ~(CSIZE | PARENB);
  71         tty.c_cflag |= CS8;
  72         tty.c_cc[VMIN] = 1;
  73         tty.c_cc[VTIME] = 0;
  74     }
  75     if (!stdio_allow_signal) {
  76         tty.c_lflag &= ~ISIG;
  77     }
  78
  79     tcsetattr(0, TCSANOW, &tty);
  80 }
  81
  82 static void term_stdio_handler(int sig)
  83 {
  84     /* restore echo after resume from suspend. */
  85     qemu_chr_set_echo_stdio(NULL, stdio_echo_state);
  86 }
  87
  88 static void qemu_chr_open_stdio(Chardev *chr,
  89                                 ChardevBackend *backend,
  90                                 bool *be_opened,
  91                                 Error **errp)
  92 {
  93     ChardevStdio *opts = backend->u.stdio.data;
  94     struct sigaction act;
  95
  96     if (is_daemonized()) {
  97         error_setg(errp, "cannot use stdio with -daemonize");
  98         return;
  99     }
 100
 101     if (stdio_in_use) {
 102         error_setg(errp, "cannot use stdio by multiple character devices");
 103         return;
 104     }
 105
 106     stdio_in_use = true;
 107     old_fd0_flags = fcntl(0, F_GETFL);
 108     old_fd1_flags = fcntl(1, F_GETFL);
 109     tcgetattr(0, &oldtty);
 110     if (!g_unix_set_fd_nonblocking(0, true, NULL)) {
 111         error_setg_errno(errp, errno, "Failed to set FD nonblocking");
 112         return;
 113     }
 114     atexit(term_exit);
 115
 116     memset(&act, 0, sizeof(act));
 117     act.sa_handler = term_stdio_handler;
 118     sigaction(SIGCONT, &act, NULL);
 119
 120     qemu_chr_open_fd(chr, 0, 1);
 121
 122     stdio_allow_signal = !opts->has_signal || opts->signal;
 123     qemu_chr_set_echo_stdio(chr, false);
 124 }
 125 #endif
 126
 127 static void qemu_chr_parse_stdio(QemuOpts *opts, ChardevBackend *backend,
 128                                  Error **errp)
 129 {
 130     ChardevStdio *stdio;
 131
 132     backend->type = CHARDEV_BACKEND_KIND_STDIO;
 133     stdio = backend->u.stdio.data = g_new0(ChardevStdio, 1);
 134     qemu_chr_parse_common(opts, qapi_ChardevStdio_base(stdio));
 135     stdio->has_signal = true;
 136     stdio->signal = qemu_opt_get_bool(opts, "signal", true);
 137 }
 138
 139 static void char_stdio_class_init(ObjectClass *oc, void *data)
 140 {
 141     ChardevClass *cc = CHARDEV_CLASS(oc);
 142
 143     cc->parse = qemu_chr_parse_stdio;
 144 #ifndef _WIN32
 145     cc->open = qemu_chr_open_stdio;
 146     cc->chr_set_echo = qemu_chr_set_echo_stdio;
 147 #endif
 148 }
 149
 150 static void char_stdio_finalize(Object *obj)
 151 {
 152 #ifndef _WIN32
 153     term_exit();
 154 #endif
 155 }
 156
 157 static const TypeInfo char_stdio_type_info = {
 158     .name = TYPE_CHARDEV_STDIO,
 159 #ifdef _WIN32
 160     .parent = TYPE_CHARDEV_WIN_STDIO,
 161 #else
 162     .parent = TYPE_CHARDEV_FD,
 163 #endif
 164     .instance_finalize = char_stdio_finalize,
 165     .class_init = char_stdio_class_init,
 166 };
 167
 168 static void register_types(void)
 169 {
 170     type_register_static(&char_stdio_type_info);
 171 }
 172
 173 type_init(register_types);