Add additional AOS and LOS functionality

configure.ac

@@ -52,6 +52,16 @@ else
     AC_MSG_ERROR(Gpredict requires libgoocanvas-2.0-dev)
 fi
 
+# check for gstreamer (optional)
+if pkg-config --atleast-version=1.0 gstreamer-1.0; then
+    CFLAGS="$CFLAGS `pkg-config --cflags gstreamer-1.0`"
+    LIBS="$LIBS `pkg-config --libs gstreamer-1.0`"
+    havelibgstreamer=true;
+    AC_DEFINE(HAS_LIBGSTREAMER, 1, [Define if libgstreamer is available])
+else
+    havelibgstreamer=false;
+fi
+
 # check for libgps (optional)
 if pkg-config --atleast-version=2.90 libgps; then
     CFLAGS="$CFLAGS `pkg-config --cflags libgps`"
@@ -94,6 +104,11 @@ GTHR_V=`pkg-config --modversion gthread-2.0`
 GDK_V=`pkg-config --modversion gdk-3.0`
 GTK_V=`pkg-config --modversion gtk+-3.0`
 GOOC_V=`pkg-config --modversion goocanvas-2.0`
+if test "$havelibgstreamer" = true ; then
+   GST_V=`pkg-config --modversion gstreamer-1.0`
+else
+   GST_V='Not found'
+fi
 CURL_V=`pkg-config --modversion libcurl`
 if test "$havelibgps" = true ; then
    GPS_V=`pkg-config --modversion libgps`
@@ -132,6 +147,7 @@ echo Gthread version.... : $GTHR_V
 echo Gdk version........ : $GDK_V
 echo Gtk+ version....... : $GTK_V
 echo GooCanvas version.. : $GOOC_V
+echo gstreamer version.. : $GST_V
 echo Libcurl version.... : $CURL_V
 if test "$havelibgps" = true ; then
    echo Libgps version..... : $GPS_V

src/Makefile.am

@@ -37,6 +37,7 @@ gpredict_SOURCES = \
     first-time.c first-time.h \
     gpredict-help.c gpredict-help.h \
     gpredict-utils.c gpredict-utils.h \
+    gtk-audio.c gtk-audio.h \
     gtk-azel-plot.c gtk-azel-plot.h \
     gtk-event-list.c gtk-event-list.h \
     gtk-event-list-popup.c gtk-event-list-popup.h \

src/gtk-audio.c

@@ -0,0 +1,81 @@
+/* Functions to play audio files (.wav etc).
+ *
+ * This uses the gstreamer library & requires the playbin and wav plugins.
+ * On Windows/msys2, these can be installed with:
+ * pacman -S mingw-w64-i686-gstreamer mingw-w64-i686-gst-plugins-base mingw-w64-i686-gst-plugins-good
+ * On Centos 8:
+ * yum install gstreamer1 streamer1-plugins-good gstreamer1-devel
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <build-config.h>
+#endif
+
+#include <glib.h>
+#include <glib/gi18n.h>
+#ifdef HAS_LIBGSTREAMER
+#include <gst/gst.h>
+#endif
+
+#include "gtk-audio.h"
+#include "sat-log.h"
+
+/* Convert path to absolute path */
+gchar *
+absolute_path (const gchar *filename)
+{
+    gchar *abs_path;
+
+    if (!g_path_is_absolute (filename))
+    {
+        gchar *cwd = NULL;
+
+        cwd = g_get_current_dir();
+        abs_path = g_build_filename(cwd, filename, NULL);
+        g_free(cwd);
+    }
+    else
+        abs_path = g_strdup(filename);
+
+    return abs_path;
+}
+
+#ifdef HAS_LIBGSTREAMER
+void audio_play_uri(gchar *uri)
+{
+    GstElement *pipeline;
+
+    /* playbin requires an absolute URI. E.g. file:///absolute/path.
+       We try to see if the input uri is actually a file path. If so, we make it
+       into a uri.
+     */
+    if (g_file_test(uri, G_FILE_TEST_EXISTS))
+    {
+        gchar *filename;
+        GError *error = NULL;
+
+        filename = absolute_path(uri);
+        uri = g_filename_to_uri(filename, NULL, &error);
+        g_free(filename);
+    }
+
+    /* Play audio using playbin plugin. */
+    pipeline = gst_element_factory_make("playbin", NULL);
+    if (!pipeline) {
+        /* This will fail if the playbin plugin isn't found. */
+        sat_log_log(SAT_LOG_LEVEL_ERROR,
+                    _("%s: Failed to create playbin pipeline. Are gst plugins installed?"),
+                    __func__);
+        return;
+    }
+    g_object_set(pipeline, "uri", uri, NULL);
+    gst_element_set_state(pipeline, GST_STATE_PLAYING);
+}
+#else
+void audio_play_uri(gchar *uri)
+{
+    sat_log_log(SAT_LOG_LEVEL_WARN,
+        _("%s: Request to play audio \"%s\", but gpredict was compiled without libgstreamer"),
+        __func__, uri);
+}
+#endif

src/gtk-audio.h

@@ -0,0 +1,21 @@
+#ifndef __GTK_AUDIO_H
+#define __GTK_AUDIO_H 1
+
+#include <glib.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**< Play audio file. E.g. .wav 
+     uri can be a relative pathname or URI.   
+     E.g. ../path/file.wav, file:///path/something.wav or http://server/file.wav
+     Supported file formats depend on which plugins are installed. 
+     */  
+void audio_play_uri(gchar *uri);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif