QConsoleInput.cpp

   1 /* ***** BEGIN LICENSE BLOCK *****
   2  *
   3  * The MIT License
   4  *
   5  * Copyright (c) 2008 BBC Research
   6  *
   7  * Permission is hereby granted, free of charge, to any person obtaining a copy
   8  * of this software and associated documentation files (the "Software"), to deal
   9  * in the Software without restriction, including without limitation the rights
  10  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  11  * copies of the Software, and to permit persons to whom the Software is
  12  * furnished to do so, subject to the following conditions:
  13  *
  14  * The above copyright notice and this permission notice shall be included in
  15  * all copies or substantial portions of the Software.
  16  *
  17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  20  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  21  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  22  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  23  * THE SOFTWARE.
  24  *
  25  * ***** END LICENSE BLOCK ***** */
  26
  27 #include <QtGlobal>
  28 #include <QApplication>
  29 #include <QObject>
  30 #include <QKeyEvent>
  31
  32 #ifdef Q_OS_UNIX
  33 #include <signal.h>
  34 #include <termios.h>
  35 #include <unistd.h>
  36 #endif
  37
  38 #include "QConsoleInput.h"
  39
  40 QConsoleInput::QConsoleInput(QObject* in_event_handler)
  41 {
  42         event_handler = in_event_handler;
  43         start();
  44 }
  45
  46 int
  47 asciiToKey(char c)
  48 {
  49         if (!isprint(c))
  50                 return 0;
  51         return toupper(c);
  52 }
  53
  54 Qt::KeyboardModifiers
  55 asciiToMod(char c)
  56 {
  57         Qt::KeyboardModifiers mod = Qt::NoModifier;
  58         if (isupper(c))
  59                 mod |= Qt::ShiftModifier;
  60         return mod;
  61 }
  62
  63 void
  64 QConsoleInput::run()
  65 {
  66         if (!isatty(STDIN_FILENO))
  67                 /* we can only do this if we are on a tty */
  68                 return;
  69
  70         /* Protect against reading while backgrounded
  71          * (causes read to return -EIO) */
  72         signal(SIGTTIN, SIG_IGN);
  73         /* hack: flag set when we get -EIO on read */
  74         /* No signal is generated to inform a process if it suddenly
  75          * becomes the foreground process, so some hack is required */
  76         bool hack_got_eio;
  77
  78         /* put the terminal into cbreak mode, aka character mode, so that read()
  79          * doesn't block waiting for a newline before returning */
  80         struct termios tio;
  81         tio_orig = new termios;
  82         tcgetattr(STDIN_FILENO, tio_orig);
  83         tcgetattr(STDIN_FILENO, &tio);
  84         tio.c_lflag &= ~(ICANON | ECHO);
  85         tcsetattr(STDIN_FILENO, TCSANOW, &tio);
  86
  87         while (1) {
  88                 if (hack_got_eio && tcgetpgrp(STDIN_FILENO) == getpid()) {
  89                         tcgetattr(STDIN_FILENO, &tio);
  90                         tio.c_lflag &= ~(ICANON | ECHO);
  91                         tcsetattr(STDIN_FILENO, TCSANOW, &tio);
  92                         hack_got_eio = 0;
  93                 }
  94
  95                 char c = 'a';
  96                 if (read(STDIN_FILENO, &c, 1) <= 0) {
  97                         sleep(1);
  98                         hack_got_eio = 1;
  99                         continue;
 100                 }
 101
 102                 Qt::KeyboardModifiers mods = asciiToMod(c);
 103                 int key = asciiToKey(c);
 104
 105                 QKeyEvent *ev = new QKeyEvent(QEvent::KeyPress, key, mods);
 106 #if QT_VERSION >= 0x040400
 107                 if (event_handler->isWidgetType())
 108                         QApplication::setActiveWindow(reinterpret_cast<QWidget*>(event_handler));
 109 #endif
 110                 QCoreApplication::postEvent(event_handler, ev);
 111         }
 112 }
 113
 114 QConsoleInput::~QConsoleInput()
 115 {
 116         terminate();
 117         wait();
 118
 119         signal(SIGTTIN, SIG_DFL);
 120
 121         /* restore tty mode at exit */
 122         if (!isatty(STDIN_FILENO))
 123                 return;
 124
 125         tcsetattr(STDIN_FILENO, TCSANOW, tio_orig);
 126
 127         delete tio_orig;
 128 }