LXR qemu/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 */
  41static struct termios oldtty;
  42static int old_fd0_flags;
  43static bool stdio_in_use;
  44static bool stdio_allow_signal;
  45static bool stdio_echo_state;
  46
  47static 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
  55static 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
  78static 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
  84static 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
 121static 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
 133static 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
 144static void char_stdio_finalize(Object *obj)
 145{
 146#ifndef _WIN32
 147    term_exit();
 148#endif
 149}
 150
 151static 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
 162static void register_types(void)
 163{
 164    type_register_static(&char_stdio_type_info);
 165}
 166
 167type_init(register_types);
 168