1 files changed, 807 insertions, 0 deletions

diff --git a/src/contrib/service/conversation/gnunet-helper-audio-record.c b/src/contrib/service/conversation/gnunet-helper-audio-record.c
new file mode 100644
index 000000000..060a7c779
--- /dev/null
+++ b/src/contrib/service/conversation/gnunet-helper-audio-record.c
@@ -0,0 +1,807 @@
+/*
+     This file is part of GNUnet.
+     Copyright (C) 2013 GNUnet e.V.
+
+     GNUnet is free software: you can redistribute it and/or modify it
+     under the terms of the GNU Affero General Public License as published
+     by the Free Software Foundation, either version 3 of the License,
+     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
+     Affero General Public License for more details.
+
+     You should have received a copy of the GNU Affero General Public License
+     along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+     SPDX-License-Identifier: AGPL3.0-or-later
+ */
+/**
+ * @file conversation/gnunet-helper-audio-record.c
+ * @brief program to record audio data from the microphone
+ * @author Siomon Dieterle
+ * @author Andreas Fuchs
+ * @author Christian Grothoff
+ */
+#include "platform.h"
+#include "gnunet_util_lib.h"
+#include "gnunet_protocols.h"
+#include "conversation.h"
+#include "gnunet_constants.h"
+#include "gnunet_core_service.h"
+
+#include <pulse/simple.h>
+#include <pulse/error.h>
+#include <pulse/rtclock.h>
+
+#include <pulse/pulseaudio.h>
+#include <opus/opus.h>
+#include <opus/opus_types.h>
+#include <ogg/ogg.h>
+
+#define DEBUG_RECORD_PURE_OGG 1
+
+/**
+ * Sampling rate
+ */
+#define SAMPLING_RATE 48000
+
+/**
+ * How many ms of audio to buffer before encoding them.
+ * Possible values:
+ * 60, 40, 20, 10, 5, 2.5
+ */
+#define FRAME_SIZE_MS 40
+
+/**
+ * How many samples to buffer before encoding them.
+ */
+#define FRAME_SIZE (SAMPLING_RATE / 1000 * FRAME_SIZE_MS)
+
+/**
+ * Pages are committed when their size goes over this value.
+ * Note that in practice we flush pages VERY often (every frame),
+ * which means that pages NEVER really get to be this big.
+ * With one-packet-per-page, pages are roughly 100-300 bytes each.
+ *
+ * This value is chosen to make MAX_PAYLOAD_BYTES=1024 fit
+ * into a single page.
+ */
+#define PAGE_WATERLINE 800
+
+/**
+ * Maximum length of opus payload
+ */
+#define MAX_PAYLOAD_BYTES 1024
+
+/**
+ * Number of channels
+ */
+#define CHANNELS 1
+
+/**
+ * Configures the encoder's expected packet loss percentage.
+ *
+ * Higher values will trigger progressively more loss resistant behavior
+ * in the encoder at the expense of quality at a given bitrate
+ * in the lossless case, but greater quality under loss.
+ */
+#define CONV_OPUS_PACKET_LOSS_PERCENTAGE 1
+
+/**
+ * Configures the encoder's computational complexity.
+ *
+ * The supported range is 0-10 inclusive with 10 representing
+ * the highest complexity.
+ */
+#define CONV_OPUS_ENCODING_COMPLEXITY 10
+
+/**
+ * Configures the encoder's use of inband forward error correction (FEC).
+ *
+ * Note: This is only applicable to the LPC layer.
+ */
+#define CONV_OPUS_INBAND_FEC 1
+
+/**
+ * Configures the type of signal being encoded.
+ *
+ * This is a hint which helps the encoder's mode selection.
+ *
+ * Possible values:
+ * OPUS_AUTO - (default) Encoder detects the type automatically.
+ * OPUS_SIGNAL_VOICE - Bias thresholds towards choosing LPC or Hybrid modes.
+ * OPUS_SIGNAL_MUSIC - Bias thresholds towards choosing MDCT modes.
+ */
+#define CONV_OPUS_SIGNAL OPUS_SIGNAL_VOICE
+
+/**
+ * Coding mode.
+ *
+ * Possible values:
+ * OPUS_APPLICATION_VOIP - gives best quality at a given bitrate for voice
+ * signals. It enhances the input signal by high-pass filtering and
+ * emphasizing formants and harmonics. Optionally it includes in-band forward
+ * error correction to protect against packet loss. Use this mode for typical
+ * VoIP applications. Because of the enhancement, even at high bitrates
+ * the output may sound different from the input.
+ * OPUS_APPLICATION_AUDIO - gives best quality at a given bitrate for most
+ * non-voice signals like music. Use this mode for music and mixed
+ * (music/voice) content, broadcast, and applications requiring less than
+ * 15 ms of coding delay.
+ * OPUS_APPLICATION_RESTRICTED_LOWDELAY - configures low-delay mode that
+ * disables the speech-optimized mode in exchange for slightly reduced delay.
+ * This mode can only be set on an newly initialized or freshly reset encoder
+ * because it changes the codec delay.
+ */
+#define CONV_OPUS_APP_TYPE OPUS_APPLICATION_VOIP
+
+/**
+ * Specification for recording. May change in the future to spec negotiation.
+ */
+static pa_sample_spec sample_spec = {
+  .format = PA_SAMPLE_FLOAT32LE,
+  .rate = SAMPLING_RATE,
+  .channels = CHANNELS
+};
+
+GNUNET_NETWORK_STRUCT_BEGIN
+
+/* OggOpus spec says the numbers must be in little-endian order */
+struct OpusHeadPacket
+{
+  uint8_t magic[8];
+  uint8_t version;
+  uint8_t channels;
+  uint16_t preskip GNUNET_PACKED;
+  uint32_t sampling_rate GNUNET_PACKED;
+  uint16_t gain GNUNET_PACKED;
+  uint8_t channel_mapping;
+};
+
+struct OpusCommentsPacket
+{
+  uint8_t magic[8];
+  uint32_t vendor_length;
+  /* followed by:
+     char vendor[vendor_length];
+     uint32_t string_count;
+     followed by @a string_count pairs of:
+       uint32_t string_length;
+       char string[string_length];
+   */
+};
+
+GNUNET_NETWORK_STRUCT_END
+
+/**
+ * Pulseaudio mainloop api
+ */
+static pa_mainloop_api *mainloop_api;
+
+/**
+ * Pulseaudio mainloop
+ */
+static pa_mainloop *m;
+
+/**
+ * Pulseaudio context
+ */
+static pa_context *context;
+
+/**
+ * Pulseaudio recording stream
+ */
+static pa_stream *stream_in;
+
+/**
+ * Pulseaudio io events
+ */
+static pa_io_event *stdio_event;
+
+/**
+ * OPUS encoder
+ */
+static OpusEncoder *enc;
+
+/**
+ * Buffer for encoded data
+ */
+static unsigned char *opus_data;
+
+/**
+ * PCM data buffer for one OPUS frame
+ */
+static float *pcm_buffer;
+
+/**
+ * Length of the pcm data needed for one OPUS frame
+ */
+static int pcm_length;
+
+/**
+ * Audio buffer
+ */
+static char *transmit_buffer;
+
+/**
+ * Length of audio buffer
+ */
+static size_t transmit_buffer_length;
+
+/**
+ * Read index for transmit buffer
+ */
+static size_t transmit_buffer_index;
+
+/**
+ * Audio message skeleton
+ */
+static struct AudioMessage *audio_message;
+
+/**
+ * Ogg muxer state
+ */
+static ogg_stream_state os;
+
+/**
+ * Ogg packet id
+ */
+static int32_t packet_id;
+
+/**
+ * Ogg granule for current packet
+ */
+static int64_t enc_granulepos;
+
+#ifdef DEBUG_RECORD_PURE_OGG
+/**
+ * 1 to not to write GNUnet message headers,
+ * producing pure playable ogg output
+ */
+static int dump_pure_ogg;
+#endif
+
+/**
+ * Pulseaudio shutdown task
+ */
+static void
+quit (int ret)
+{
+  mainloop_api->quit (mainloop_api,
+                      ret);
+  exit (ret);
+}
+
+
+static void
+write_data (const char *ptr,
+            size_t msg_size)
+{
+  ssize_t ret;
+  size_t off;
+
+  off = 0;
+  while (off < msg_size)
+  {
+    ret = write (STDOUT_FILENO,
+                 &ptr[off],
+                 msg_size - off);
+    if (0 >= ret)
+    {
+      if (-1 == ret)
+        GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR,
+                             "write");
+      quit (2);
+    }
+    off += ret;
+  }
+}
+
+
+static void
+write_page (ogg_page *og)
+{
+  static unsigned long long toff;
+  size_t msg_size;
+
+  msg_size = sizeof(struct AudioMessage) + og->header_len + og->body_len;
+  audio_message->header.size = htons ((uint16_t) msg_size);
+  GNUNET_memcpy (&audio_message[1], og->header, og->header_len);
+  GNUNET_memcpy (((char *) &audio_message[1]) + og->header_len, og->body,
+                 og->body_len);
+
+  toff += msg_size;
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "Sending %u bytes of audio data (total: %llu)\n",
+              (unsigned int) msg_size,
+              toff);
+#ifdef DEBUG_RECORD_PURE_OGG
+  if (dump_pure_ogg)
+    write_data ((const char *) &audio_message[1],
+                og->header_len + og->body_len);
+  else
+#endif
+  write_data ((const char *) audio_message,
+              msg_size);
+}
+
+
+/**
+ * Creates OPUS packets from PCM data
+ */
+static void
+packetizer ()
+{
+  char *nbuf;
+  size_t new_size;
+  int32_t len;
+  ogg_packet op;
+  ogg_page og;
+
+  while (transmit_buffer_length >= transmit_buffer_index + pcm_length)
+  {
+    GNUNET_memcpy (pcm_buffer,
+                   &transmit_buffer[transmit_buffer_index],
+                   pcm_length);
+    transmit_buffer_index += pcm_length;
+    len =
+      opus_encode_float (enc, pcm_buffer, FRAME_SIZE, opus_data,
+                         MAX_PAYLOAD_BYTES);
+
+    if (len < 0)
+    {
+      GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                  _ ("opus_encode_float() failed: %s. Aborting\n"),
+                  opus_strerror (len));
+      quit (5);
+    }
+    if (((uint32_t) len) > UINT16_MAX - sizeof(struct AudioMessage))
+    {
+      GNUNET_break (0);
+      continue;
+    }
+
+    /* As per OggOpus spec, granule is calculated as if the audio
+       had 48kHz sampling rate. */
+    enc_granulepos += FRAME_SIZE * 48000 / SAMPLING_RATE;
+
+    op.packet = (unsigned char *) opus_data;
+    op.bytes = len;
+    op.b_o_s = 0;
+    op.e_o_s = 0;
+    op.granulepos = enc_granulepos;
+    op.packetno = packet_id++;
+    ogg_stream_packetin (&os, &op);
+
+    while (ogg_stream_flush_fill (&os, &og, PAGE_WATERLINE))
+    {
+      if (((unsigned long long) og.header_len)
+          + ((unsigned long long) og.body_len) >
+          UINT16_MAX - sizeof(struct AudioMessage))
+      {
+        GNUNET_assert (0);
+        continue;
+      }
+      write_page (&og);
+    }
+  }
+
+  new_size = transmit_buffer_length - transmit_buffer_index;
+  if (0 != new_size)
+  {
+    nbuf = pa_xmalloc (new_size);
+    memmove (nbuf,
+             &transmit_buffer[transmit_buffer_index],
+             new_size);
+    pa_xfree (transmit_buffer);
+    transmit_buffer = nbuf;
+  }
+  else
+  {
+    pa_xfree (transmit_buffer);
+    transmit_buffer = NULL;
+  }
+  transmit_buffer_index = 0;
+  transmit_buffer_length = new_size;
+}
+
+
+/**
+ * Pulseaudio callback when new data is available.
+ */
+static void
+stream_read_callback (pa_stream *s,
+                      size_t length,
+                      void *userdata)
+{
+  const void *data;
+
+  (void) userdata;
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "Got %u/%d bytes of PCM data\n",
+              (unsigned int) length,
+              pcm_length);
+
+  GNUNET_assert (NULL != s);
+  GNUNET_assert (length > 0);
+  if (stdio_event)
+    mainloop_api->io_enable (stdio_event, PA_IO_EVENT_OUTPUT);
+
+  if (pa_stream_peek (s, (const void **) &data, &length) < 0)
+  {
+    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                _ ("pa_stream_peek() failed: %s\n"),
+                pa_strerror (pa_context_errno (context)));
+    quit (1);
+    return;
+  }
+  GNUNET_assert (NULL != data);
+  GNUNET_assert (length > 0);
+  if (NULL != transmit_buffer)
+  {
+    transmit_buffer = pa_xrealloc (transmit_buffer,
+                                   transmit_buffer_length + length);
+    GNUNET_memcpy (&transmit_buffer[transmit_buffer_length],
+                   data,
+                   length);
+    transmit_buffer_length += length;
+  }
+  else
+  {
+    transmit_buffer = pa_xmalloc (length);
+    GNUNET_memcpy (transmit_buffer, data, length);
+    transmit_buffer_length = length;
+    transmit_buffer_index = 0;
+  }
+  pa_stream_drop (s);
+  packetizer ();
+}
+
+
+/**
+ * Exit callback for SIGTERM and SIGINT
+ */
+static void
+exit_signal_callback (pa_mainloop_api *m,
+                      pa_signal_event *e,
+                      int sig,
+                      void *userdata)
+{
+  (void) m;
+  (void) e;
+  (void) sig;
+  (void) userdata;
+  GNUNET_log (GNUNET_ERROR_TYPE_INFO,
+              _ ("Got signal, exiting.\n"));
+  quit (1);
+}
+
+
+/**
+ * Pulseaudio stream state callback
+ */
+static void
+stream_state_callback (pa_stream *s,
+                       void *userdata)
+{
+  (void) userdata;
+  GNUNET_assert (NULL != s);
+  switch (pa_stream_get_state (s))
+  {
+  case PA_STREAM_CREATING:
+  case PA_STREAM_TERMINATED:
+    break;
+
+  case PA_STREAM_READY:
+    {
+      const pa_buffer_attr *a;
+      char cmt[PA_CHANNEL_MAP_SNPRINT_MAX];
+      char sst[PA_SAMPLE_SPEC_SNPRINT_MAX];
+
+      GNUNET_log (GNUNET_ERROR_TYPE_INFO,
+                  _ ("Stream successfully created.\n"));
+
+      if (! (a = pa_stream_get_buffer_attr (s)))
+      {
+        GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                    _ ("pa_stream_get_buffer_attr() failed: %s\n"),
+                    pa_strerror (pa_context_errno
+                                   (pa_stream_get_context (s))));
+      }
+      else
+      {
+        GNUNET_log (GNUNET_ERROR_TYPE_INFO,
+                    _ ("Buffer metrics: maxlength=%u, fragsize=%u\n"),
+                    a->maxlength, a->fragsize);
+      }
+      GNUNET_log (GNUNET_ERROR_TYPE_INFO,
+                  _ ("Using sample spec '%s', channel map '%s'.\n"),
+                  pa_sample_spec_snprint (sst, sizeof(sst),
+                                          pa_stream_get_sample_spec (s)),
+                  pa_channel_map_snprint (cmt, sizeof(cmt),
+                                          pa_stream_get_channel_map (s)));
+
+      GNUNET_log (GNUNET_ERROR_TYPE_INFO,
+                  _ ("Connected to device %s (%u, %ssuspended).\n"),
+                  pa_stream_get_device_name (s),
+                  pa_stream_get_device_index (s),
+                  pa_stream_is_suspended (s) ? "" : "not ");
+    }
+    break;
+
+  case PA_STREAM_FAILED:
+  default:
+    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                _ ("Stream error: %s\n"),
+                pa_strerror (pa_context_errno (pa_stream_get_context (s))));
+    quit (1);
+  }
+}
+
+
+/**
+ * Pulseaudio context state callback
+ */
+static void
+context_state_callback (pa_context *c,
+                        void *userdata)
+{
+  (void) userdata;
+  GNUNET_assert (c);
+
+  switch (pa_context_get_state (c))
+  {
+  case PA_CONTEXT_CONNECTING:
+  case PA_CONTEXT_AUTHORIZING:
+  case PA_CONTEXT_SETTING_NAME:
+    break;
+
+  case PA_CONTEXT_READY:
+    {
+      int r;
+      pa_buffer_attr na;
+
+      GNUNET_assert (! stream_in);
+      GNUNET_log (GNUNET_ERROR_TYPE_INFO,
+                  _ ("Connection established.\n"));
+      if (! (stream_in =
+               pa_stream_new (c, "GNUNET_VoIP recorder", &sample_spec, NULL)))
+      {
+        GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                    _ ("pa_stream_new() failed: %s\n"),
+                    pa_strerror (pa_context_errno (c)));
+        goto fail;
+      }
+      pa_stream_set_state_callback (stream_in, &stream_state_callback, NULL);
+      pa_stream_set_read_callback (stream_in, &stream_read_callback, NULL);
+      memset (&na, 0, sizeof(na));
+      na.maxlength = UINT32_MAX;
+      na.fragsize = pcm_length;
+      if ((r = pa_stream_connect_record (stream_in, NULL, &na,
+                                         PA_STREAM_ADJUST_LATENCY)) < 0)
+      {
+        GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                    _ ("pa_stream_connect_record() failed: %s\n"),
+                    pa_strerror (pa_context_errno (c)));
+        goto fail;
+      }
+
+      break;
+    }
+
+  case PA_CONTEXT_TERMINATED:
+    quit (0);
+    break;
+
+  case PA_CONTEXT_FAILED:
+  default:
+    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                _ ("Connection failure: %s\n"),
+                pa_strerror (pa_context_errno (c)));
+    goto fail;
+  }
+  return;
+
+fail:
+  quit (1);
+}
+
+
+/**
+ * Pulsaudio init
+ */
+static void
+pa_init ()
+{
+  int r;
+  int i;
+
+  if (! pa_sample_spec_valid (&sample_spec))
+  {
+    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                _ ("Wrong Spec\n"));
+  }
+  /* set up main record loop */
+  if (! (m = pa_mainloop_new ()))
+  {
+    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                _ ("pa_mainloop_new() failed.\n"));
+  }
+  mainloop_api = pa_mainloop_get_api (m);
+
+  /* listen to signals */
+  r = pa_signal_init (mainloop_api);
+  GNUNET_assert (r == 0);
+  pa_signal_new (SIGINT, &exit_signal_callback, NULL);
+  pa_signal_new (SIGTERM, &exit_signal_callback, NULL);
+
+  /* connect to the main pulseaudio context */
+
+  if (! (context = pa_context_new (mainloop_api, "GNUNET VoIP")))
+  {
+    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                _ ("pa_context_new() failed.\n"));
+  }
+  pa_context_set_state_callback (context, &context_state_callback, NULL);
+  if (pa_context_connect (context, NULL, 0, NULL) < 0)
+  {
+    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                _ ("pa_context_connect() failed: %s\n"),
+                pa_strerror (pa_context_errno (context)));
+  }
+  if (pa_mainloop_run (m, &i) < 0)
+  {
+    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                _ ("pa_mainloop_run() failed.\n"));
+  }
+}
+
+
+/**
+ * OPUS init
+ */
+static void
+opus_init ()
+{
+  int err;
+
+  pcm_length = FRAME_SIZE * CHANNELS * sizeof(float);
+  pcm_buffer = pa_xmalloc (pcm_length);
+  opus_data = GNUNET_malloc (MAX_PAYLOAD_BYTES);
+  enc = opus_encoder_create (SAMPLING_RATE,
+                             CHANNELS,
+                             CONV_OPUS_APP_TYPE,
+                             &err);
+  opus_encoder_ctl (enc,
+                    OPUS_SET_PACKET_LOSS_PERC (
+                      CONV_OPUS_PACKET_LOSS_PERCENTAGE));
+  opus_encoder_ctl (enc,
+                    OPUS_SET_COMPLEXITY (CONV_OPUS_ENCODING_COMPLEXITY));
+  opus_encoder_ctl (enc,
+                    OPUS_SET_INBAND_FEC (CONV_OPUS_INBAND_FEC));
+  opus_encoder_ctl (enc,
+                    OPUS_SET_SIGNAL (CONV_OPUS_SIGNAL));
+}
+
+
+static void
+ogg_init ()
+{
+  int serialno;
+  struct OpusHeadPacket headpacket;
+  struct OpusCommentsPacket *commentspacket;
+  size_t commentspacket_len;
+
+  serialno = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_STRONG,
+                                       0x7FFFFFFF);
+  /*Initialize Ogg stream struct*/
+  if (-1 == ogg_stream_init (&os, serialno))
+  {
+    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                _ ("ogg_stream_init() failed.\n"));
+    exit (3);
+  }
+
+  packet_id = 0;
+
+  /*Write header*/
+  {
+    ogg_packet op;
+    ogg_page og;
+    const char *opusver;
+    int vendor_length;
+
+    GNUNET_memcpy (headpacket.magic, "OpusHead", 8);
+    headpacket.version = 1;
+    headpacket.channels = CHANNELS;
+    headpacket.preskip = GNUNET_htole16 (0);
+    headpacket.sampling_rate = GNUNET_htole32 (SAMPLING_RATE);
+    headpacket.gain = GNUNET_htole16 (0);
+    headpacket.channel_mapping = 0; /* Mono or stereo */
+
+    op.packet = (unsigned char *) &headpacket;
+    op.bytes = sizeof(headpacket);
+    op.b_o_s = 1;
+    op.e_o_s = 0;
+    op.granulepos = 0;
+    op.packetno = packet_id++;
+    ogg_stream_packetin (&os, &op);
+
+    /* Head packet must be alone on its page */
+    while (ogg_stream_flush (&os, &og))
+    {
+      write_page (&og);
+    }
+
+    commentspacket_len = sizeof(*commentspacket);
+    opusver = opus_get_version_string ();
+    vendor_length = strlen (opusver);
+    commentspacket_len += vendor_length;
+    commentspacket_len += sizeof(uint32_t);
+
+    commentspacket = (struct OpusCommentsPacket *) malloc (commentspacket_len);
+    if (NULL == commentspacket)
+    {
+      GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                  _ ("Failed to allocate %u bytes for second packet\n"),
+                  (unsigned int) commentspacket_len);
+      exit (5);
+    }
+
+    GNUNET_memcpy (commentspacket->magic, "OpusTags", 8);
+    commentspacket->vendor_length = GNUNET_htole32 (vendor_length);
+    GNUNET_memcpy (&commentspacket[1], opusver, vendor_length);
+    *(uint32_t *) &((char *) &commentspacket[1])[vendor_length] = \
+      GNUNET_htole32 (0);    /* no tags */
+
+    op.packet = (unsigned char *) commentspacket;
+    op.bytes = commentspacket_len;
+    op.b_o_s = 0;
+    op.e_o_s = 0;
+    op.granulepos = 0;
+    op.packetno = packet_id++;
+    ogg_stream_packetin (&os, &op);
+
+    /* Comment packets must not be mixed with audio packets on their pages */
+    while (ogg_stream_flush (&os, &og))
+    {
+      write_page (&og);
+    }
+
+    free (commentspacket);
+  }
+}
+
+
+/**
+ * The main function for the record helper.
+ *
+ * @param argc number of arguments from the command line
+ * @param argv command line arguments
+ * @return 0 ok, 1 on error
+ */
+int
+main (int argc,
+      char *argv[])
+{
+  (void) argc;
+  (void) argv;
+  GNUNET_assert (GNUNET_OK ==
+                 GNUNET_log_setup ("gnunet-helper-audio-record",
+                                   "WARNING",
+                                   NULL));
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "Audio source starts\n");
+  audio_message = GNUNET_malloc (UINT16_MAX);
+  audio_message->header.type = htons (GNUNET_MESSAGE_TYPE_CONVERSATION_AUDIO);
+
+#ifdef DEBUG_RECORD_PURE_OGG
+  dump_pure_ogg = getenv ("GNUNET_RECORD_PURE_OGG") ? 1 : 0;
+#endif
+  ogg_init ();
+  opus_init ();
+  pa_init ();
+  return 0;
+}