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