-implement speaker library

4 files changed, 208 insertions, 5 deletions

diff --git a/src/conversation/Makefile.am b/src/conversation/Makefile.am
index ac2f47612..10fd26014 100644
--- a/src/conversation/Makefile.am
+++ b/src/conversation/Makefile.am
@@ -16,6 +16,7 @@ AM_CPPFLAGS = \
 
 lib_LTLIBRARIES = \
  libgnunetmicrophone.la \
+ libgnunetspeaker.la \
  libgnunetconversation.la
 
 pkgcfgdir= $(prefix)/share/gnunet/config.d/
@@ -30,12 +31,21 @@ libgnunetmicrophone_la_LDFLAGS = \
   $(GNUNET_LDFLAGS)  $(WINFLAGS) \
   -version-info 0:0:0
 
+libgnunetspeaker_la_SOURCES = \
+  speaker.c 
+libgnunetspeaker_la_LIBADD = \
+  -lgnunetutil
+libgnunetspeaker_la_LDFLAGS = \
+  $(GNUNET_LDFLAGS)  $(WINFLAGS) \
+  -version-info 0:0:0
+
 
 libgnunetconversation_la_SOURCES = \
   conversation_api.c \
   conversation_api2.c 
 libgnunetconversation_la_LIBADD = \
   libgnunetmicrophone.la \
+  libgnunetspeaker.la \
   $(top_builddir)/src/gns/libgnunetgns.la \
   $(top_builddir)/src/namestore/libgnunetnamestore.la \
   $(top_builddir)/src/util/libgnunetutil.la 
diff --git a/src/conversation/microphone.c b/src/conversation/microphone.c
index 8e9b9e241..53ac5cb86 100644
--- a/src/conversation/microphone.c
+++ b/src/conversation/microphone.c
@@ -101,11 +101,12 @@ enable (void *cls,
         void *rdc_cls)
 {
   struct Microphone *mic = cls;  
-  char * const record_helper_argv[] = 
+  static char * const record_helper_argv[] = 
   {
     "gnunet-helper-audio-record",
     NULL
   };
+
   mic->rdc = rdc;
   mic->rdc_cls = rdc_cls;
   mic->record_helper = GNUNET_HELPER_start (GNUNET_NO,
diff --git a/src/conversation/speaker.c b/src/conversation/speaker.c
new file mode 100644
index 000000000..255b79ee3
--- /dev/null
+++ b/src/conversation/speaker.c
@@ -0,0 +1,190 @@
+/*
+  This file is part of GNUnet
+  (C) 2013 Christian Grothoff (and other contributing authors)
+  
+  GNUnet is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published
+  by the Free Software Foundation; either version 3, or (at your
+  option) any later version.
+  
+  GNUnet 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
+  General Public License for more details.
+  
+  You should have received a copy of the GNU General Public License
+  along with GNUnet; see the file COPYING.  If not, write to the
+  Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+  Boston, MA 02111-1307, USA.
+ */
+
+/**
+ * @file conversation/speaker.c
+ * @brief API to access an audio speaker; provides access to hardware speakers
+ * @author Simon Dieterle
+ * @author Andreas Fuchs
+ * @author Christian Grothoff
+ */
+#include "platform.h"
+#include "gnunet_speaker_lib.h"
+#include "conversation.h"
+
+
+/**
+ * Internal data structures for the speaker.
+ */
+struct Speaker
+{
+  /**
+   * Our configuration.
+   */
+  const struct GNUNET_CONFIGURATION_Handle *cfg;
+
+  /**
+   * Handle for the playback helper
+   */
+  struct GNUNET_HELPER_Handle *playback_helper;
+
+};
+
+
+/**
+ * Function that enables a speaker.
+ *
+ * @param cls closure with the `struct Speaker`
+ * @return #GNUNET_OK on success, #GNUNET_SYSERR on error
+ */
+static int
+enable (void *cls)
+{
+  struct Speaker *spe = cls;  
+  static char *playback_helper_argv[] = 
+  {
+    "gnunet-helper-audio-playback",
+    NULL
+  };
+  
+  spe->playback_helper = GNUNET_HELPER_start (GNUNET_NO,
+                                              "gnunet-helper-audio-playback",
+                                              playback_helper_argv,
+                                              NULL, 
+                                              NULL, spe);
+  if (NULL == spe->playback_helper)
+  {
+    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                _("Could not start playback audio helper.\n"));
+    return GNUNET_SYSERR;
+  }
+  return GNUNET_OK;
+}
+
+
+/**
+ * Function that disables a speaker.
+ *
+ * @param cls closure with the `struct Speaker`
+ */
+static void
+disable (void *cls)
+{
+  struct Speaker *spe = cls;
+
+  if (NULL == spe->playback_helper)
+  {
+    GNUNET_break (0);
+    return;
+  }
+  GNUNET_break (GNUNET_OK ==
+                GNUNET_HELPER_kill (spe->playback_helper, GNUNET_NO));
+  GNUNET_HELPER_destroy (spe->playback_helper);
+  spe->playback_helper = NULL;
+}
+
+
+/**
+ * Function to destroy a speaker.
+ *
+ * @param cls closure with the `struct Speaker`
+ */
+static void
+destroy (void *cls)
+{
+  struct Speaker *spe = cls;
+
+  if (NULL != spe->playback_helper)
+    disable (spe);
+}
+
+
+/**
+ * Function to cause a speaker to play audio data.
+ *
+ * @param cls clsoure with the `struct Speaker`
+ * @param data_size number of bytes in @a data
+ * @param data audio data to play, format is
+ *        opaque to the API but should be OPUS.
+ */
+static void
+play (void *cls,
+      size_t data_size,
+      const void *data)
+{
+  struct Speaker *spe = cls;
+  const struct AudioMessage *am;
+
+  if (NULL == spe->playback_helper)
+  {
+    GNUNET_break (0);
+    return;
+  }
+  if (sizeof (struct AudioMessage) != data_size)
+  {
+    GNUNET_break (0);
+    return;
+  }
+  am = (const struct AudioMessage *) data;
+  (void) GNUNET_HELPER_send (spe->playback_helper,
+                             &am->header, 
+                             GNUNET_YES, 
+                             NULL, NULL);
+}
+
+
+/**
+ * Create a speaker that corresponds to the speaker hardware
+ * of our system.
+ *
+ * @param cfg configuration to use
+ * @return NULL on error
+ */
+struct GNUNET_SPEAKER_Handle *
+GNUNET_SPEAKER_create_from_hardware (const struct GNUNET_CONFIGURATION_Handle *cfg)
+{
+  struct GNUNET_SPEAKER_Handle *speaker;
+  struct Speaker *spe;
+
+  spe = GNUNET_new (struct Speaker);
+  spe->cfg = cfg;
+  speaker = GNUNET_new (struct GNUNET_SPEAKER_Handle);
+  speaker->cls = spe;
+  speaker->enable_speaker = &enable;
+  speaker->play = &play;
+  speaker->disable_speaker = &disable;
+  speaker->destroy_speaker = &destroy;
+  return speaker;
+}
+
+
+/**
+ * Destroy a speaker.
+ *
+ * @param speaker speaker to destroy
+ */
+void
+GNUNET_SPEAKER_destroy (struct GNUNET_SPEAKER_Handle *speaker)
+{
+  speaker->destroy_speaker (speaker->cls);
+  GNUNET_free (speaker);
+}
+
+/* end of speaker.c */
diff --git a/src/include/gnunet_speaker_lib.h b/src/include/gnunet_speaker_lib.h
index 7a6eb028b..bdb91d6a1 100644
--- a/src/include/gnunet_speaker_lib.h
+++ b/src/include/gnunet_speaker_lib.h
@@ -36,10 +36,12 @@ extern "C"
 #endif
 #endif
 
+#include "gnunet_util_lib.h"
+
 /**
  * Function that enables a speaker.
  *
- * @param cls clsoure
+ * @param cls closure
  * @return #GNUNET_OK on success, #GNUNET_SYSERR on error
  */
 typedef int (*GNUNET_SPEAKER_EnableCallback)(void *cls);
@@ -47,21 +49,21 @@ typedef int (*GNUNET_SPEAKER_EnableCallback)(void *cls);
 /**
  * Function that disables a speaker.
  *
- * @param cls clsoure
+ * @param cls closure
  */
 typedef void (*GNUNET_SPEAKER_DisableCallback)(void *cls);
 
 /**
  * Function to destroy a speaker.
  *
- * @param cls clsoure
+ * @param cls closure
  */
 typedef void (*GNUNET_SPEAKER_DestroyCallback)(void *cls);
 
 /**
  * Function to cause a speaker to play audio data.
  *
- * @param cls clsoure
+ * @param cls closure
  * @param data_size number of bytes in @a data
  * @param data audio data to play, format is
  *        opaque to the API but should be OPUS.