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