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/option.h"
  27 #include "qemu/sockets.h"
  28 #include "qapi/error.h"
  29 #include "chardev/char.h"
  30
  31 #ifdef _WIN32
  32 #include "chardev/char-win.h"
  33 #include "chardev/char-win-stdio.h"
  34 #else
  35 #include <termios.h>
  36 #include "chardev/char-fd.h"
  37 #endif
  38
  39 #ifndef _WIN32
  40 /* init terminal so that we can grab keys */
  41 static struct termios oldtty;
  42 static int old_fd0_flags;
  43 static bool stdio_in_use;
  44 static bool stdio_allow_signal;
  45 static bool stdio_echo_state;
  46
  47 static void term_exit(void)
  48 {
  49     if (stdio_in_use) {
  50         tcsetattr(0, TCSANOW, &oldtty);
  51         fcntl(0, F_SETFL, old_fd0_flags);
  52     }
  53 }
  54
  55 static void qemu_chr_set_echo_stdio(Chardev *chr, bool echo)
  56 {
  57     struct termios tty;
  58
  59     stdio_echo_state = echo;
  60     tty = oldtty;
  61     if (!echo) {
  62         tty.c_iflag &= ~(IGNBRK | BRKINT | PARMRK | ISTRIP
  63                          | INLCR | IGNCR | ICRNL | IXON);
  64         tty.c_oflag |= OPOST;
  65         tty.c_lflag &= ~(ECHO | ECHONL | ICANON | IEXTEN);
  66         tty.c_cflag &= ~(CSIZE | PARENB);
  67         tty.c_cflag |= CS8;
  68         tty.c_cc[VMIN] = 1;
  69         tty.c_cc[VTIME] = 0;
  70     }
  71     if (!stdio_allow_signal) {
  72         tty.c_lflag &= ~ISIG;
  73     }
  74
  75     tcsetattr(0, TCSANOW, &tty);
  76 }
  77
  78 static void term_stdio_handler(int sig)
  79 {
  80     /* restore echo after resume from suspend. */
  81     qemu_chr_set_echo_stdio(NULL, stdio_echo_state);
  82 }
  83
  84 static void qemu_chr_open_stdio(Chardev *chr,
  85                                 ChardevBackend *backend,
  86                                 bool *be_opened,
  87                                 Error **errp)
  88 {
  89     ChardevStdio *opts = backend->u.stdio.data;
  90     struct sigaction act;
  91
  92     if (is_daemonized()) {
  93         error_setg(errp, "cannot use stdio with -daemonize");
  94         return;
  95     }
  96
  97     if (stdio_in_use) {
  98         error_setg(errp, "cannot use stdio by multiple character devices");
  99         return;
 100     }
 101
 102     stdio_in_use = true;
 103     old_fd0_flags = fcntl(0, F_GETFL);
 104     tcgetattr(0, &oldtty);
 105     qemu_set_nonblock(0);
 106     atexit(term_exit);
 107
 108     memset(&act, 0, sizeof(act));
 109     act.sa_handler = term_stdio_handler;
 110     sigaction(SIGCONT, &act, NULL);
 111
 112     qemu_chr_open_fd(chr, 0, 1);
 113
 114     if (opts->has_signal) {
 115         stdio_allow_signal = opts->signal;
 116     }
 117     qemu_chr_set_echo_stdio(chr, false);
 118 }
 119 #endif
 120
 121 static void qemu_chr_parse_stdio(QemuOpts *opts, ChardevBackend *backend,
 122                                  Error **errp)
 123 {
 124     ChardevStdio *stdio;
 125
 126     backend->type = CHARDEV_BACKEND_KIND_STDIO;
 127     stdio = backend->u.stdio.data = g_new0(ChardevStdio, 1);
 128     qemu_chr_parse_common(opts, qapi_ChardevStdio_base(stdio));
 129     stdio->has_signal = true;
 130     stdio->signal = qemu_opt_get_bool(opts, "signal", true);
 131 }
 132
 133 static void char_stdio_class_init(ObjectClass *oc, void *data)
 134 {
 135     ChardevClass *cc = CHARDEV_CLASS(oc);
 136
 137     cc->parse = qemu_chr_parse_stdio;
 138 #ifndef _WIN32
 139     cc->open = qemu_chr_open_stdio;
 140     cc->chr_set_echo = qemu_chr_set_echo_stdio;
 141 #endif
 142 }
 143
 144 static void char_stdio_finalize(Object *obj)
 145 {
 146 #ifndef _WIN32
 147     term_exit();
 148 #endif
 149 }
 150
 151 static const TypeInfo char_stdio_type_info = {
 152     .name = TYPE_CHARDEV_STDIO,
 153 #ifdef _WIN32
 154     .parent = TYPE_CHARDEV_WIN_STDIO,
 155 #else
 156     .parent = TYPE_CHARDEV_FD,
 157 #endif
 158     .instance_finalize = char_stdio_finalize,
 159     .class_init = char_stdio_class_init,
 160 };
 161
 162 static void register_types(void)
 163 {
 164     type_register_static(&char_stdio_type_info);
 165 }
 166
 167 type_init(register_types);