gstreamer/tools/gst-play-kb.c
Antonio Ospite cfc1be0d61 tools: play: fix leaving STDIN in non-blocking mode after exit
gst-play-1.0 sets STDIN to non-blocking mode to have the input
characters read as soon as they arrive.

However, when gst_play_kb_set_key_handler() gets called from
restore_terminal() it forgets to restore the STDIN blocking status.

This can result in broken behavior for cli command executed in the same
terminal after gst-play-1.0 exited.

It turns out that putting STDIN in non-blocking mode is not even the
proper way to achieve the desired effect, instead VMIN and VTIME in
struct termios should be set to 0.

Let's do that, and don't mess with the STDIN blocking mode now that it's
not necessary.

https://bugzilla.gnome.org/show_bug.cgi?id=794591
2018-03-26 11:59:56 +01:00

140 lines
3.6 KiB
C

/* GStreamer command line playback testing utility - keyboard handling helpers
*
* Copyright (C) 2013 Tim-Philipp Müller <tim centricular net>
* Copyright (C) 2013 Centricular Ltd
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "gst-play-kb.h"
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#ifdef G_OS_UNIX
#include <unistd.h>
#include <termios.h>
#endif
#include <gst/gst.h>
/* This is all not thread-safe, but doesn't have to be really */
#ifdef G_OS_UNIX
static struct termios term_settings;
static gboolean term_settings_saved = FALSE;
static GstPlayKbFunc kb_callback;
static gpointer kb_callback_data;
static gulong io_watch_id;
static gboolean
gst_play_kb_io_cb (GIOChannel * ioc, GIOCondition cond, gpointer user_data)
{
GIOStatus status;
if (cond & G_IO_IN) {
gchar buf[16] = { 0, };
gsize read;
status = g_io_channel_read_chars (ioc, buf, sizeof (buf) - 1, &read, NULL);
if (status == G_IO_STATUS_ERROR)
return FALSE;
if (status == G_IO_STATUS_NORMAL) {
if (kb_callback)
kb_callback (buf, kb_callback_data);
}
}
return TRUE; /* call us again */
}
gboolean
gst_play_kb_set_key_handler (GstPlayKbFunc kb_func, gpointer user_data)
{
GIOChannel *ioc;
if (!isatty (STDIN_FILENO)) {
GST_INFO ("stdin is not connected to a terminal");
return FALSE;
}
if (io_watch_id > 0) {
g_source_remove (io_watch_id);
io_watch_id = 0;
}
if (kb_func == NULL && term_settings_saved) {
/* restore terminal settings */
if (tcsetattr (STDIN_FILENO, TCSAFLUSH, &term_settings) == 0)
term_settings_saved = FALSE;
else
g_warning ("could not restore terminal attributes");
setvbuf (stdin, NULL, _IOLBF, 0);
}
if (kb_func != NULL) {
struct termios new_settings;
if (!term_settings_saved) {
if (tcgetattr (STDIN_FILENO, &term_settings) != 0) {
g_warning ("could not save terminal attributes");
return FALSE;
}
term_settings_saved = TRUE;
/* Echo off, canonical mode off, extended input processing off */
new_settings = term_settings;
new_settings.c_lflag &= ~(ECHO | ICANON | IEXTEN);
new_settings.c_cc[VMIN] = 0;
new_settings.c_cc[VTIME] = 0;
if (tcsetattr (STDIN_FILENO, TCSAFLUSH, &new_settings) != 0) {
g_warning ("Could not set terminal state");
return FALSE;
}
setvbuf (stdin, NULL, _IONBF, 0);
}
}
ioc = g_io_channel_unix_new (STDIN_FILENO);
io_watch_id = g_io_add_watch_full (ioc, G_PRIORITY_DEFAULT, G_IO_IN,
(GIOFunc) gst_play_kb_io_cb, user_data, NULL);
g_io_channel_unref (ioc);
kb_callback = kb_func;
kb_callback_data = user_data;
return TRUE;
}
#else /* !G_OS_UNIX */
gboolean
gst_play_kb_set_key_handler (GstPlayKbFunc key_func, gpointer user_data)
{
GST_FIXME ("Keyboard handling for this OS needs to be implemented");
return FALSE;
}
#endif /* !G_OS_UNIX */