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