tools: play: add --interactive switch and basic keyboard handling

Only pause/play with spacebar for now.

tools/Makefile.am

@@ -8,7 +8,9 @@ bin_PROGRAMS = \
 
 gst_discoverer_@GST_API_VERSION@_SOURCES = gst-discoverer.c
 
-gst_play_@GST_API_VERSION@_SOURCES = gst-play.c
+gst_play_@GST_API_VERSION@_SOURCES = gst-play.c gst-play-kb.c gst-play-kb.h
+
+noinst_HEADERS = gst-play-kb.h
 
 CLEANFILES = $(bin_SCRIPTS) $(bin_PROGRAMS)
 

tools/gst-play-kb.c

@@ -0,0 +1,142 @@
+/* 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;
+  int flags;
+
+  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);
+
+      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);
+
+  /* make non-blocking */
+  flags = g_io_channel_get_flags (ioc);
+  g_io_channel_set_flags (ioc, flags | G_IO_FLAG_NONBLOCK, NULL);
+
+  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");
+}
+
+#endif /* !G_OS_UNIX */

tools/gst-play-kb.h

@@ -0,0 +1,35 @@
+/* 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.
+ */
+#ifndef __GST_PLAY_KB_INCLUDED__
+#define __GST_PLAY_KB_INCLUDED__
+
+#include <glib.h>
+
+#define GST_PLAY_KB_KEY_UP    "\033[A"
+#define GST_PLAY_KB_KEY_DOWN  "\033[B"
+#define GST_PLAY_KB_KEY_RIGHT "\033[C"
+#define GST_PLAY_KB_KEY_LEFT  "\033[D"
+
+typedef void (*GstPlayKbFunc) (const gchar * kb_input, gpointer user_data);
+
+gboolean gst_play_kb_set_key_handler (GstPlayKbFunc kb_func, gpointer user_data);
+
+#endif /* __GST_PLAY_KB_INCLUDED__ */

tools/gst-play.c

@@ -27,6 +27,10 @@
 #include <gst/gst-i18n-app.h>
 #include <gst/pbutils/pbutils.h>
 #include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+
+#include "gst-play-kb.h"
 
 GST_DEBUG_CATEGORY (play_debug);
 #define GST_CAT_DEFAULT play_debug
@@ -49,6 +53,8 @@ typedef struct
   gboolean buffering;
   gboolean is_live;
 
+  GstState desired_state;       /* as per user interaction, PAUSED or PLAYING */
+
   /* configuration */
   gboolean gapless;
 } GstPlay;
@@ -101,6 +107,8 @@ play_new (gchar ** uris, const gchar * audio_sink, const gchar * video_sink,
   play->buffering = FALSE;
   play->is_live = FALSE;
 
+  play->desired_state = GST_STATE_PLAYING;
+
   play->gapless = gapless;
   if (gapless) {
     g_signal_connect (play->playbin, "about-to-finish",
@@ -177,7 +185,7 @@ play_bus_msg (GstBus * bus, GstMessage * msg, gpointer user_data)
         /* a 100% message means buffering is done */
         if (play->buffering) {
           play->buffering = FALSE;
-          gst_element_set_state (play->playbin, GST_STATE_PLAYING);
+          gst_element_set_state (play->playbin, play->desired_state);
         }
       } else {
         /* buffering... */
@@ -276,6 +284,7 @@ play_timeout (gpointer user_data)
 {
   GstPlay *play = user_data;
   gint64 pos = -1, dur = -1;
+  gchar status[64] = { 0, };
 
   if (play->buffering)
     return TRUE;
@@ -283,6 +292,11 @@ play_timeout (gpointer user_data)
   gst_element_query_position (play->playbin, GST_FORMAT_TIME, &pos);
   gst_element_query_duration (play->playbin, GST_FORMAT_TIME, &dur);
 
+  if (play->desired_state == GST_STATE_PAUSED)
+    g_snprintf (status, sizeof (status), "Paused");
+  else
+    memset (status, ' ', sizeof (status) - 1);
+
   if (pos >= 0 && dur > 0) {
     gchar dstr[32], pstr[32];
 
@@ -291,7 +305,7 @@ play_timeout (gpointer user_data)
     pstr[9] = '\0';
     g_snprintf (dstr, 32, "%" GST_TIME_FORMAT, GST_TIME_ARGS (dur));
     dstr[9] = '\0';
-    g_print ("%s / %s\r", pstr, dstr);
+    g_print ("%s / %s %s\r", pstr, dstr, status);
   }
 
   return TRUE;
@@ -335,7 +349,7 @@ play_next (GstPlay * play)
 
   g_object_set (play->playbin, "uri", next_uri, NULL);
 
-  sret = gst_element_set_state (play->playbin, GST_STATE_PLAYING);
+  sret = gst_element_set_state (play->playbin, play->desired_state);
   switch (sret) {
     case GST_STATE_CHANGE_FAILURE:
       /* ignore, we should get an error message posted on the bus */
@@ -445,12 +459,52 @@ shuffle_uris (gchar ** uris, guint num)
   }
 }
 
+static void
+restore_terminal (void)
+{
+  gst_play_kb_set_key_handler (NULL, NULL);
+}
+
+static void
+toggle_paused (GstPlay * play)
+{
+  if (play->desired_state == GST_STATE_PLAYING)
+    play->desired_state = GST_STATE_PAUSED;
+  else
+    play->desired_state = GST_STATE_PLAYING;
+
+  if (!play->buffering) {
+    gst_element_set_state (play->playbin, play->desired_state);
+  } else if (play->desired_state == GST_STATE_PLAYING) {
+    g_print ("\nWill play as soon as buffering finishes)\n");
+  }
+}
+
+static void
+keyboard_cb (const gchar * key_input, gpointer user_data)
+{
+  GstPlay *play = (GstPlay *) user_data;
+
+  switch (g_ascii_tolower (key_input[0])) {
+    case ' ':
+      toggle_paused (play);
+      break;
+    case 27:                   /* ESC */
+    default:
+      GST_INFO ("keyboard input:");
+      while (*key_input)
+        GST_INFO ("  code %3d", *key_input++);
+      break;
+  }
+}
+
 int
 main (int argc, char **argv)
 {
   GstPlay *play;
   GPtrArray *playlist;
   gboolean print_version = FALSE;
+  gboolean interactive = FALSE; /* FIXME: maybe enable by default? */
   gboolean gapless = FALSE;
   gboolean shuffle = FALSE;
   gchar **filenames = NULL;
@@ -471,6 +525,8 @@ main (int argc, char **argv)
         N_("Enable gapless playback"), NULL},
     {"shuffle", 0, 0, G_OPTION_ARG_NONE, &shuffle,
         N_("Shuffle playlist"), NULL},
+    {"interactive", 0, 0, G_OPTION_ARG_NONE, &interactive,
+        N_("interactive"), NULL},
     {G_OPTION_REMAINING, 0, 0, G_OPTION_ARG_FILENAME_ARRAY, &filenames, NULL},
     {NULL}
   };
@@ -532,9 +588,18 @@ main (int argc, char **argv)
   if (shuffle)
     shuffle_uris (uris, num);
 
-  /* play */
+  /* prepare */
   play = play_new (uris, audio_sink, video_sink, gapless);
 
+  if (interactive) {
+    if (gst_play_kb_set_key_handler (keyboard_cb, play)) {
+      atexit (restore_terminal);
+    } else {
+      g_print ("Interactive keyboard handling in terminal not available.\n");
+    }
+  }
+
+  /* play */
   do_play (play);
 
   /* clean up */