path: root/src/main.c

/*
 * vim: set sts=2 sw=2 et foldmethod=syntax :
 *
 * License: LGPL-2.1+
 * Copyright (c) 2014-15 Nirbheek Chauhan <nirbheek@centricular.com>
 *
 * 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.
 */

#include <glib-unix.h>
#include <gst/video/video.h>
#include <json-glib/json-glib.h>

#include "lib.h"
#include "encode.h"

#ifdef PLAY_DEBUG
#include "debug/local-play.h"
#endif

#define STP_STREAM_PREFIX "/stream/"
#define STP_REST_API_PREFIX "/api/"

#define STP_REST_LIST_STREAMS STP_REST_API_PREFIX "list-streams"
#define STP_REST_ABORT_STREAM STP_REST_API_PREFIX "abort-stream"
#define STP_REST_ADD_TOKEN    STP_REST_API_PREFIX "add-token"
#define STP_REST_REVOKE_TOKEN STP_REST_API_PREFIX "revoke-token"
#define STP_REST_LIST_TOKENS  STP_REST_API_PREFIX "list-tokens"

#define STP_SESSIONID(X) &X[sizeof(STP_STREAM_PREFIX)-1]

typedef struct _STPHashTables STPHashTables;

struct _STPHashTables {
  GHashTable *ctxs;
  GHashTable *tokens;
};

static int port = 8000;
static int client_timeout = 10;
static int server_timeout = 5;
static char *token_server_addrmask = NULL;
static gboolean conflict_is_restart = FALSE;
static GInetAddressMask *stp_inet_addrmask = NULL;
static GMainLoop *loop = NULL;

static GOptionEntry entries[] =
{
  { "port", 'p', 0, G_OPTION_ARG_INT, &port, "Port to listen on (default: 8000)", "PORT" },
  { "client-timeout", 0, 0, G_OPTION_ARG_INT, &client_timeout, "Outgoing client connection timeout (default: 10s)", "SECONDS" },
  { "stream-timeout", 0, 0, G_OPTION_ARG_INT, &server_timeout, "Incoming stream connection timeout (default: 5s)", "SECONDS" },
  { "token-server", 's', 0, G_OPTION_ARG_STRING, &token_server_addrmask, "Subnet (or IP addr) for the token server (default: disabled)", "ADDR/PREFIX" },
  { "conflict-is-restart", 0, 0, G_OPTION_ARG_NONE, &conflict_is_restart, "If a new PUT stream is received at the same path as an existing one, treat it as a restart instead of reporting a 409/CONFLICT (default: no)", NULL },
  { NULL }
};

static SoupServer *server;

static void stream_finished_cb (SoupMessage  *msg,
                                STPServerCtx *ctx);

static STPServerCtx*
get_server_ctx_from_msg (SoupMessage *msg,
                         GHashTable  *ctx_table)
{
  SoupURI *uri;
  STPServerCtx *ctx;

  g_object_get (msg, "uri", &uri, NULL);
  ctx = g_hash_table_lookup (ctx_table,
                             STP_SESSIONID (soup_uri_get_path (uri)));
  soup_uri_free (uri);

  if (!ctx)
    g_critical ("No matching context found for msg!\n");

  return ctx;
}

/* Validates the query, parses it, and fetches a STPStreamToken from it */
static STPStreamToken*
stp_validate_fetch_token_from_query (GHashTable  *tokens,
                                     const char  *sessionid,
                                     GHashTable  *query,
                                     guint       *http_status_code)
{
  char *query_string, *type, *udp_clients;
  STPStreamToken *token, *perms_token;

  if (!query) {
    g_debug ("Rejecting stream: no query specified");
    *http_status_code = SOUP_STATUS_BAD_REQUEST;
    return NULL;
  }

  query_string = soup_form_encode_hash (query);
  g_debug ("Recv query string: %s\n", query_string);
  g_free (query_string);

  if (stp_inet_addrmask && 
      !g_hash_table_contains (tokens, sessionid)) {
    g_debug ("Rejecting stream: unauthorized session id");
    *http_status_code = SOUP_STATUS_FORBIDDEN;
    return NULL;
  }

  token = g_new0 (STPStreamToken, 1);

  type = g_hash_table_lookup (query, "type");
  token->stream_type = stp_get_stream_type_from_string (type);

  perms_token = g_hash_table_lookup (tokens, sessionid);
  if (stp_inet_addrmask && perms_token &&
      perms_token->stream_type != token->stream_type) {
    g_debug ("Rejecting stream: Stream type does not match");
    *http_status_code = SOUP_STATUS_FORBIDDEN;
    goto err;
  }

  if (!(token->stream_type & STP_STREAM_TYPE_RTP_UDP))
    goto out;

  /* Only needed for RTP streaming */
  udp_clients = g_hash_table_lookup (query, "udp-clients");
  token->udp_clients = g_strdup (udp_clients);

  if (!token->udp_clients) {
    g_debug ("Rejecting stream: Stream type is UDP but no UDP clients specified");
    *http_status_code = SOUP_STATUS_BAD_REQUEST;
    goto err;
  }

  if (perms_token &&
      !stp_clients_is_subset (perms_token->udp_clients,
                              token->udp_clients)) {
    g_debug ("Rejecting stream: UDP client list does not match");
    *http_status_code = SOUP_STATUS_FORBIDDEN;
    goto err;
  }

out:
  g_hash_table_destroy (query);
  return token;
err:
  g_free (token);
  token = NULL;
  goto out;
}

static void
stp_abort_server_ctx (STPServerCtx *ctx)
{
  /* Abort all processing for this stream */
  if (ctx->status == STP_STATUS_STREAMING &&
      ctx->encoding != SOUP_ENCODING_CONTENT_LENGTH) {
    /* Close the PUT stream if necessary */
    ctx->status = STP_STATUS_FINISHED;
    soup_message_set_status (ctx->msg, SOUP_STATUS_GONE);
  }
  stream_finished_cb (ctx->msg, ctx);
}

/* If it's been more than 5 seconds since the last time we got
 * a chunk for a PUT request, we timeout and drop the connection */
static gboolean
increment_read_timer (STPServerCtx *ctx)
{
  ctx->seconds_since_read += 2;
  g_debug ("Checking stream read time (%i)...", ctx->seconds_since_read);
  if (ctx->seconds_since_read < server_timeout)
    return G_SOURCE_CONTINUE;

  g_debug ("Stream timed out, sending EOS\n");
  stream_finished_cb (ctx->msg, ctx);
  return G_SOURCE_REMOVE;
}

/* If it's been more than 10 seconds since the last time we wrote
 * a chunk for a GET response, we timeout and drop the connection */
static gboolean
increment_write_timer (STPClientCtx *ctx)
{
  ctx->seconds_since_write += 2;
  if (ctx->seconds_since_write < client_timeout)
    return G_SOURCE_CONTINUE;

  g_printerr ("Client timed out, cleaning up\n");
  /* FIXME: This isn't actually setting the status for client
   * connections, and clients are just left hanging */
  soup_message_set_status (ctx->msg, SOUP_STATUS_REQUEST_TIMEOUT);
  soup_message_body_complete (ctx->msg->response_body);
  stp_client_ctx_cleanup (ctx);
  return G_SOURCE_REMOVE;
}

static void
client_eos_cb (GstElement         *appsink,
               STPClientCtx *ctx)
{
  g_debug ("Received EOS for client");
  soup_message_set_status (ctx->msg, SOUP_STATUS_OK);
  soup_message_body_complete (ctx->msg->response_body);
}

static void
can_write_next_client_chunk_cb (SoupMessage        *msg,
                                STPClientCtx *ctx)
{
  ctx->seconds_since_write = 0;
  ctx->msg = msg;
  stp_print_status ("_");
}

static gboolean
invoke_write_client_chunk (STPClientCtx *ctx)
{
  GstMapInfo info;
  GstSample *sample;
  GstBuffer *buffer;
  gboolean eos;

  stp_print_status ("*");

  /* XXX: If samples are coming in too quickly, this can get invoked
   * after the client has disconnected and the SoupMessage is invalid.
   * When the client disconnects, timeout_handler_id is set to 0. */
  if (G_UNLIKELY (ctx->timeout_handler_id == 0))
    return G_SOURCE_REMOVE;

  g_signal_emit_by_name (ctx->appsink, "pull-sample", &sample);
  if (!sample) {
    g_debug ("Null sample, ending stream");
    g_object_get (ctx->appsink, "eos", &eos, NULL);
    if (eos)
      soup_message_set_status (ctx->msg, SOUP_STATUS_OK);
    else
      soup_message_set_status (ctx->msg, SOUP_STATUS_INTERNAL_SERVER_ERROR);
    soup_message_body_complete (ctx->msg->response_body);
    return G_SOURCE_REMOVE;
  }

  buffer = gst_sample_get_buffer (sample);

  /* Skip all frames till the next keyframe */
  if (!ctx->keyframe_found &&
      GST_BUFFER_FLAG_IS_SET (buffer, GST_BUFFER_FLAG_DELTA_UNIT)) {
    gst_sample_unref (sample);
    return G_SOURCE_REMOVE;
  }
  ctx->keyframe_found = TRUE;

  gst_buffer_map (buffer, &info, GST_MAP_READ);

  soup_message_body_append (ctx->msg->response_body, SOUP_MEMORY_COPY,
                            info.data, info.size); /* copy */

  gst_buffer_unmap (buffer, &info);
  gst_sample_unref (sample);

  soup_server_unpause_message (server, ctx->msg);
  stp_print_status (".");
  return G_SOURCE_REMOVE;
}

static GstFlowReturn
write_client_chunk_cb (GstElement         *appsink,
                       STPClientCtx *ctx)
{
  g_main_context_invoke_full (NULL, G_PRIORITY_DEFAULT,
                              (GSourceFunc)invoke_write_client_chunk,
                              ctx, NULL);
  return GST_FLOW_OK;
}

static void
client_finished_cb (SoupMessage        *msg,
                    STPClientCtx *ctx)
{
  stp_print_status ("Client finished/aborted, doing cleanup...\n");
  stp_client_ctx_cleanup (ctx);
}

static void
stream_finished_cb (SoupMessage  *msg,
                    STPServerCtx *ctx)
{
  gboolean ret;

  stp_print_status ("Stream finished/aborted, queueing EOS... ");

  if (!ctx->appsrc) {
    ctx->status = STP_STATUS_FINISHED;
    stp_print_status ("No need.\n");
    return;
  }

  ctx->status = STP_STATUS_FLUSHING;
  /* Incoming stream has ended; this EOS will trigger a cleanup of ctx as well */
  g_signal_emit_by_name (ctx->appsrc, "end-of-stream", &ret);
  if (ret != GST_FLOW_OK)
    g_critical ("\nUnable to emit end-of-stream after an aborted stream");
  else
    stp_print_status ("Done.\n");
}

/* This is called when the entire request body has been read */
static void
handle_request_with_body_cb (SoupServer        *server,
                             SoupMessage       *msg,
                             const char        *path,
                             GHashTable        *query,
                             SoupClientContext *client,
                             STPHashTables     *tables)
{
  STPServerCtx *server_ctx;

  if (!msg)
    return;

  g_debug ("Handling %s request on path %s", msg->method, path);

  if (msg->method == SOUP_METHOD_PUT ||
      msg->method == SOUP_METHOD_POST)
    goto PUT;
  else if (msg->method == SOUP_METHOD_GET)
    goto GET;
  else if (msg->method == SOUP_METHOD_DELETE) {
    soup_message_set_status (msg, SOUP_STATUS_METHOD_NOT_ALLOWED);
    return;
  } else {
    soup_message_set_status (msg, SOUP_STATUS_NOT_IMPLEMENTED);
    return;
  }

PUT:
  {
    /* The PUT request has finished streaming. Cleanup
     * will be done on EOS/ERROR in the gst pipeline. */
    server_ctx = get_server_ctx_from_msg (msg, tables->ctxs);
    if (!server_ctx) {
      soup_message_set_status (msg, SOUP_STATUS_NOT_FOUND);
    } else {
      if (server_ctx->encoding != SOUP_ENCODING_CONTENT_LENGTH)
        server_ctx->status = STP_STATUS_FLUSHING;
      soup_message_set_status (msg, SOUP_STATUS_OK);
    }
    return;
  }

GET:
  {
    /* A GET request was received. We connect from the pipeline to the
     * client requesting the stream and start writing the response. */
    GstCaps *caps = NULL;
    GstEvent *event;
    GstBuffer *buffer;
    GstFlowReturn ret;
    GstStateChangeReturn state_change;
    GstElement *encodebin, *bin, *tee, *q2, *appsink;
    GstPadTemplate *template;
    GstPad *srcpad, *sinkpadq2;
    STPClientCtx *client_ctx;

    server_ctx = get_server_ctx_from_msg (msg, tables->ctxs);
    if (server_ctx == NULL ||
        server_ctx->pipeline == NULL) {
      /* There's no request streaming on this path (yet) */
      soup_message_set_status (msg, SOUP_STATUS_NOT_FOUND);
      return;
    }

    /* Check if the pipeline successfully started PLAYING */
    state_change = gst_element_get_state (server_ctx->pipeline,
                                          NULL, NULL, 100*GST_MSECOND);
    switch (state_change) {
      case GST_STATE_CHANGE_SUCCESS:
        break;
      case GST_STATE_CHANGE_FAILURE:
        /* PUT stream should've  */
        g_critical ("GET request on %s, but state change failure?", path);
        soup_message_set_status (msg, SOUP_STATUS_INTERNAL_SERVER_ERROR);
        return;
      case GST_STATE_CHANGE_ASYNC:
        soup_message_set_status (msg, SOUP_STATUS_SERVICE_UNAVAILABLE);
        return;
      default:
        g_assert_not_reached ();
    }

    g_debug ("New GET request on %s\n", path);

    /* Connect appsink to tee, and start streaming */
    client_ctx = g_new0 (STPClientCtx, 1);
    client_ctx->msg = msg;
    client_ctx->server_ctx = server_ctx;

    bin = gst_bin_new (NULL);

    /* queue ! appsink */
    q2 = gst_element_factory_make ("queue", NULL);
    appsink = gst_element_factory_make ("appsink", NULL);
    g_object_set (appsink, "drop", FALSE,
                  "emit-signals", TRUE,
                  "max-buffers", 0, NULL);
    gst_bin_add_many (GST_BIN (bin), q2, appsink, NULL);
    gst_element_link (q2, appsink);

    sinkpadq2 = gst_element_get_static_pad (q2, "sink");
    client_ctx->ghostsinkpad = gst_ghost_pad_new (NULL, sinkpadq2);
    gst_element_add_pad (bin, client_ctx->ghostsinkpad);
    gst_object_unref (sinkpadq2);

    /* Request a new src pad from the tee in the pipeline */
    tee = gst_bin_get_by_name (GST_BIN (server_ctx->pipeline), "tee");
    template = gst_pad_template_new ("teesrc", GST_PAD_SRC,
                                     GST_PAD_REQUEST, GST_CAPS_ANY);
    srcpad = gst_element_request_pad (tee, template, NULL, GST_CAPS_ANY);

    /* Add to pipeline and sync state */
    gst_bin_add (GST_BIN (server_ctx->pipeline), bin);

    if (!gst_element_sync_state_with_parent (bin)) {
      g_critical ("Unable to sync appsink bin with parent pipeline\n");
      goto err;
    }

    g_debug ("appsink bin state synced successfully");

    /* t. ! queue ! appsink */
    gst_pad_link (srcpad, client_ctx->ghostsinkpad);

    /* Send the WebM stream header through the src pad first */
    caps = gst_pad_get_current_caps (srcpad);

    buffer = stp_get_streamheader_from_caps (caps);
    if (!buffer) {
      g_critical ("Unable to get streamheader from caps");
      goto force_key_unit;
    }

    ret = gst_pad_push (srcpad, buffer);
    if (ret != GST_FLOW_OK) {
      g_critical ("Unable to push streamheader: %s",
                  gst_flow_get_name (ret));
      goto err;
    }

force_key_unit:
    encodebin = gst_bin_get_by_name (GST_BIN (server_ctx->pipeline),
                                     "encodebin");
    event = gst_video_event_new_downstream_force_key_unit (GST_CLOCK_TIME_NONE,
                                                           GST_CLOCK_TIME_NONE,
                                                           GST_CLOCK_TIME_NONE,
                                                           FALSE, 1);
    if (!gst_element_send_event (encodebin, event))
      g_critical ("Couldn't send force key unit event!");
    gst_object_unref (encodebin);

    client_ctx->appsink = appsink;

    g_signal_connect (appsink, "new-sample",
                      G_CALLBACK (write_client_chunk_cb), client_ctx);
    g_signal_connect (appsink, "eos",
                      G_CALLBACK (client_eos_cb), client_ctx);
    g_signal_connect (client_ctx->msg, "wrote-chunk",
                      G_CALLBACK (can_write_next_client_chunk_cb), client_ctx);
    client_ctx->finished_handler_id = 
      g_signal_connect (client_ctx->msg, "finished",
                        G_CALLBACK (client_finished_cb), client_ctx);
    client_ctx->timeout_handler_id = \
      g_timeout_add_seconds (2, (GSourceFunc)increment_write_timer, client_ctx);

    server_ctx->clients = g_list_prepend (server_ctx->clients, client_ctx);

    /* Since we set the response as chunked, the server will
     * automatically pause the message for us, and the response
     * won't be completed till we call soup_message_body_complete() */
    soup_message_set_status (msg, SOUP_STATUS_OK);

    /* Make sure that browsers never cache our responses */
    soup_message_headers_append (msg->response_headers,
                                 "Cache-Control", "no-cache");
    soup_message_headers_append (msg->response_headers,
                                 "Cache-Control", "no-store");
    soup_message_headers_append (msg->response_headers,
                                 "Cache-Control", "must-revalidate");
    soup_message_headers_append (msg->response_headers,
                                 "Pragma", "no-cache");
    soup_message_headers_append (msg->response_headers,
                                 "Expires", "0");
    soup_message_headers_append (msg->response_headers,
                                 "Content-Type", "video/webm");

out:
    gst_object_unref (template);
    gst_object_unref (srcpad);
    gst_object_unref (tee);
    if (caps)
      gst_caps_unref (caps);
    return;
err:
    soup_message_set_status (client_ctx->msg, SOUP_STATUS_INTERNAL_SERVER_ERROR);
    soup_message_body_complete (client_ctx->msg->response_body);
    stp_client_ctx_cleanup (client_ctx);
    goto out;
  }
}

static void
got_request_body_chunk (SoupMessage  *msg,
                        SoupBuffer   *chunk,
                        STPServerCtx *ctx)
{
  GstBuffer *buffer;
  GstFlowReturn ret;

  /* XXX: Unfortunately, there doesn't seem to be a way to cancel the
   * reception of further chunks when we've prematurely set the response
   * (say due to an error), so we check if the status code is set and skip
   * all further chunks */
  if (msg->status_code != 0 ||
      ctx->status != STP_STATUS_STREAMING)
    return;

  /* We need to update this every chunk */
  ctx->msg = msg;
  ctx->seconds_since_read = 0;
  g_debug ("Got data, resetting stream read time...");

  /* Actually just a ref */
  buffer = stp_get_gst_buffer (chunk);
  g_signal_emit_by_name (ctx->appsrc, "push-buffer", buffer, &ret);
  gst_buffer_unref (buffer);
  if (ret != GST_FLOW_OK) {
    g_critical ("Unable to push buffer\n");
    soup_message_set_status (msg, SOUP_STATUS_INTERNAL_SERVER_ERROR);
    invoke_g_hash_table_remove (ctx);
    return;
  }
}

static void
request_ended_no_body_cb (SoupMessage  *msg,
                          STPServerCtx *ctx)
{
  g_critical ("Request ended without a body!");
  invoke_g_hash_table_remove (ctx);
}

static void
got_first_request_body_chunk (SoupMessage  *msg,
                              SoupBuffer   *chunk,
                              STPServerCtx *ctx)
{
  int num;

  /* Disconnect the ctx cleanup function */
  num = g_signal_handlers_disconnect_by_func (msg,
    G_CALLBACK (request_ended_no_body_cb), ctx);
  if (num != 1)
    g_critical ("Unable to remove signal handler for cleanup function!\n");

  /* Disconnect us from got-chunk */
  num = g_signal_handlers_disconnect_by_func (msg,
    G_CALLBACK (got_first_request_body_chunk), ctx);
  if (num != 1)
    g_critical ("Unable to remove signal handler for first request chunk!\n");

  ctx->msg = msg;
  ctx->pipeline = gst_pipeline_new ("pipe");

  /* The chunked request is copied into this stream
   * for consumption by the gst pipeline */
#ifdef PLAY_DEBUG
  stp_play_from_msg (ctx);
#else
  stp_encode_from_msg (ctx);
#endif

  got_request_body_chunk (msg, chunk, ctx);

  if (gst_element_set_state (ctx->pipeline, GST_STATE_PLAYING) ==
      GST_STATE_CHANGE_FAILURE) {
    g_critical ("Unable to set pipeline to PLAYING\n");
    soup_message_set_status (msg, SOUP_STATUS_INTERNAL_SERVER_ERROR);
    invoke_g_hash_table_remove (ctx);
  } else {
    g_debug ("Set pipeline to PLAYING");
  }

  /* Connect a different method for all further chunks */
  g_signal_connect (msg, "got-chunk",
                    G_CALLBACK (got_request_body_chunk), ctx);

  if (ctx->encoding != SOUP_ENCODING_CONTENT_LENGTH)
    /* Our incoming stream ends if the stream ends only if
     * we're using a chunked request encoding.
     *
     * This will also be called when the client sending
     * the PUT request disconnects prematurely */
    g_signal_connect (msg, "finished",
                      G_CALLBACK (stream_finished_cb), ctx);
}

static void
handle_request_with_headers_cb (SoupServer        *server,
                                SoupMessage       *msg,
                                const char        *path,
                                GHashTable        *query,
                                SoupClientContext *client,
                                STPHashTables     *tables)
{
  const char *sessionid;

#ifdef HEADERS_DEBUG
  SoupMessageHeadersIter iter;
  const char *name, *value;
  soup_message_headers_iter_init (&iter, msg->request_headers);
  while (soup_message_headers_iter_next (&iter, &name, &value))
    g_debug ("%s: %s", name, value);
#endif

  g_debug ("%s on uri %s", msg->method, path);

  /* Token API methods are handled in the server callbacks,
   * so we ignore those paths here. */
  if (g_str_has_prefix (path, STP_REST_API_PREFIX))
    goto out;

  /* Reject non-stream-prefix requests */
  if (!g_str_has_prefix (path, STP_STREAM_PREFIX)) {
    soup_message_set_status (msg, SOUP_STATUS_NOT_FOUND);
    goto out;
  }
  /* Remove the leading '/stream/' to get the session id */
  sessionid = STP_SESSIONID(path);

  if (msg->method == SOUP_METHOD_PUT ||
      msg->method == SOUP_METHOD_POST)
    /* Incoming stream; do everything needed */
    goto PUT;
  else if (msg->method == SOUP_METHOD_GET)
    /* Just set response headers as appropriate */
    goto GET;
  else if (msg->method == SOUP_METHOD_DELETE) {
    soup_message_set_status (msg, SOUP_STATUS_METHOD_NOT_ALLOWED);
    goto out;
  } else {
    /* Nothing to do; server doesn't implement this method */
    soup_message_set_status (msg, SOUP_STATUS_NOT_IMPLEMENTED);
    goto out;
  }

PUT: {
    guint http_status_code;
    const char *content_range;
    SoupEncoding encoding;
    gboolean connection_exists;
    STPServerCtx *ctx;
    STPStreamToken *token;

    token = stp_validate_fetch_token_from_query (tables->tokens,
                                                 sessionid, query,
                                                 &http_status_code);
    if (!token) {
      soup_message_set_status (msg, http_status_code);
      goto out;
    }

    connection_exists = g_hash_table_contains (tables->ctxs, sessionid);

    /* Data might be sent to us in one of three ways:
     * 1. Chunked encoding with the stream (and request body) sent in chunks
     * 2. Content-Length encoding with the entire stream in one chunk
     * 3. A persistent Content-Length encoding connection, and subsequent
     *    requests can send more stream data, forever, subject to a timeout.
     *    The first request will send a Content-Length request, and
     *    subsequent ones will only have Content-Length + Content-Range set */
    encoding = soup_message_headers_get_encoding (msg->request_headers);
    switch (encoding) {
      case SOUP_ENCODING_CHUNKED:
        g_debug ("Chunked encoding detected!");
        if (connection_exists) {
          /* There's already a chunked request streaming on this path */
          g_critical ("Recv duplicate request on the same URI: %s", path);
          soup_message_set_status (msg, SOUP_STATUS_CONFLICT);
          goto PUT_out;
        }
        break;
      case SOUP_ENCODING_CONTENT_LENGTH:
        g_debug ("Content-Length encoding detected!");
        content_range = soup_message_headers_get_one (msg->request_headers,
                                                      "Content-Range");
        /* TODO: Right now, we don't check if the Content-Range is valid,
         * and just pass the data to the pipeline. */
        if (connection_exists && !content_range) {
          /* A connection already exists, and this one isn't a continuation
           * of the previous one, so it's a conflict... unless the 
           * '--conflict-is-restart' option has been specified. */
          if (conflict_is_restart) {
            g_debug ("A connection already exists; forcing a restart");
            ctx = get_server_ctx_from_msg (msg, tables->ctxs);
            stream_finished_cb (ctx->msg, ctx);
            goto new_conn;
          }
          g_critical ("Recv Content-Length PUT on '%s' without Content-Range", path);
          soup_message_set_status (msg, SOUP_STATUS_CONFLICT);
          goto PUT_out;
        }
        if (!connection_exists && content_range) {
          /* We cancelled this connection, but we got another request which is
           * a continuation of the previous one */
          soup_message_set_status (msg, SOUP_STATUS_GONE);
          goto PUT_out;
        }
        break;
      case SOUP_ENCODING_EOF:
      case SOUP_ENCODING_UNRECOGNIZED:
      case SOUP_ENCODING_NONE:
      case SOUP_ENCODING_BYTERANGES:
        g_critical ("Unknown encoding!");
        soup_message_set_status (msg, SOUP_STATUS_BAD_REQUEST);
        goto PUT_out;
      default:
        g_critical ("Unsupported encoding?");
        soup_message_set_status (msg, SOUP_STATUS_BAD_REQUEST);
        goto PUT_out;
    }

    /* Whether the incoming stream is chunked or fixed length, we want to
     * handle it chunked, so tell libsoup to not collect chunks for
     * forming a complete request body */
    soup_message_body_set_accumulate (msg->request_body, FALSE);

    if (connection_exists) {
      g_debug ("Stream already exists, connecting everything to that...");
      ctx = get_server_ctx_from_msg (msg, tables->ctxs);
      if (ctx->status != STP_STATUS_STREAMING) {
        g_critical ("Recv more data on '%s' after timeout", path);
        soup_message_set_status (msg, SOUP_STATUS_REQUEST_TIMEOUT);
        goto PUT_out;
      }
      /* The chunks we'll get are a continuation of the previous one */
      g_signal_connect (msg, "got-chunk",
                        G_CALLBACK (got_request_body_chunk), ctx);
      goto PUT_out;
    }

  new_conn:
    /* This is a new connection; treat it as such */
    ctx = g_new0 (STPServerCtx, 1);
    ctx->stream_type = token->stream_type;
    if (ctx->stream_type & STP_STREAM_TYPE_RTP_UDP)
      ctx->udp_clients = g_strdup (token->udp_clients);
    ctx->msg = msg;
    ctx->encoding = encoding;
    ctx->status = STP_STATUS_STREAMING;
    ctx->parent_ctx_table = tables->ctxs;
    ctx->sessionid = g_strdup (sessionid);
    g_hash_table_insert (tables->ctxs, ctx->sessionid, ctx);
    g_debug ("New PUT stream on %s\n", path);

    g_signal_connect (msg, "got-chunk",
                      G_CALLBACK (got_first_request_body_chunk), ctx);
    /* If we don't get any data after this, we have to cleanup ctx
     * otherwise we'll leak it */
    g_signal_connect (msg, "finished",
                      G_CALLBACK (request_ended_no_body_cb), ctx);
    if (encoding == SOUP_ENCODING_CONTENT_LENGTH)
      ctx->timeout_handler_id =
        g_timeout_add_seconds (2, (GSourceFunc)increment_read_timer, ctx);
  PUT_out:
    stp_stream_token_free (token);
    goto out;
  }

GET: {
    STPServerCtx *server_ctx;

    server_ctx = g_hash_table_lookup (tables->ctxs, sessionid);

    if (!server_ctx ||
        !(server_ctx->stream_type & STP_STREAM_TYPE_HTTP)) {
      stp_print_status ("No HTTP GET stream on URI: %s\n", path);
      soup_message_set_status (msg, SOUP_STATUS_NOT_FOUND);
      goto out;
    }

    /* Our response will be chunked, and not with a fixed Content-Length */
    soup_message_headers_set_encoding (msg->response_headers, SOUP_ENCODING_CHUNKED);
    /* The request body isn't fixed length, so tell libsoup to
     * not collect chunks for forming a complete request body */
    soup_message_body_set_accumulate (msg->response_body, FALSE);
  }

out:
  return;
}

static void
handle_add_token_cb (SoupServer        *server,
                     SoupMessage       *msg,
                     const char        *path,
                     GHashTable        *query,
                     SoupClientContext *client,
                     STPHashTables     *tables)
{
  if (msg->method == SOUP_METHOD_POST) {
    goto POST;
  } else if (g_strcmp0 (path, STP_REST_ADD_TOKEN) != 0) {
    soup_message_set_status (msg, SOUP_STATUS_NOT_FOUND);
    goto out;
  } else if (msg->method == SOUP_METHOD_PUT ||
             msg->method == SOUP_METHOD_GET ||
             msg->method == SOUP_METHOD_DELETE) {
    soup_message_set_status (msg, SOUP_STATUS_METHOD_NOT_ALLOWED);
    goto out;
  } else {
    soup_message_set_status (msg, SOUP_STATUS_NOT_IMPLEMENTED);
    goto out;
  }

POST: {
    STPStreamToken *token;
    const char *type, *sessionid, *udp_clients;

    if (!stp_validate_token_server (stp_inet_addrmask, client)) {
      g_debug ("Attempted to access token API from unauthorized host");
      soup_message_set_status (msg, SOUP_STATUS_FORBIDDEN);
      goto out;
    }

    if (!query || 
        !g_hash_table_contains (query, "sessionid") ||
        !g_hash_table_contains (query, "type")) {
      soup_message_set_status (msg, SOUP_STATUS_BAD_REQUEST);
      goto out;
    }

    sessionid = g_hash_table_lookup (query, "sessionid");
    type = g_hash_table_lookup (query, "type");
    udp_clients = g_hash_table_lookup (query, "udp-clients");

    token = g_new0 (STPStreamToken, 1);
    token->stream_type = stp_get_stream_type_from_string (type);

    if ((udp_clients == NULL) &&
        (token->stream_type & STP_STREAM_TYPE_RTP_UDP)) {
      g_free (token);
      soup_message_set_status (msg, SOUP_STATUS_BAD_REQUEST);
      goto out;
    }

    token->udp_clients = g_strdup (udp_clients);

    /* We don't care if there's already an identical token, and
     * we don't care if there's ongoing streams with this token */
    g_hash_table_insert (tables->tokens, g_strdup (sessionid), token);

    soup_message_set_status (msg, SOUP_STATUS_OK);
  }

out:
  return;
}

static void
handle_revoke_token_cb (SoupServer        *server,
                        SoupMessage       *msg,
                        const char        *path,
                        GHashTable        *query,
                        SoupClientContext *client,
                        STPHashTables     *tables)
{
  if (msg->method == SOUP_METHOD_DELETE) {
    goto DELETE;
  } else if (g_strcmp0 (path, STP_REST_REVOKE_TOKEN) != 0) {
    soup_message_set_status (msg, SOUP_STATUS_NOT_FOUND);
    goto out;
  } else if (msg->method == SOUP_METHOD_PUT ||
             msg->method == SOUP_METHOD_GET ||
             msg->method == SOUP_METHOD_POST) {
    soup_message_set_status (msg, SOUP_STATUS_METHOD_NOT_ALLOWED);
    goto out;
  } else {
    soup_message_set_status (msg, SOUP_STATUS_NOT_IMPLEMENTED);
    goto out;
  }

DELETE: {
    char *sessionid;

    if (!stp_validate_token_server (stp_inet_addrmask, client)) {
      g_debug ("Attempted to access token API from unauthorized host");
      soup_message_set_status (msg, SOUP_STATUS_FORBIDDEN);
      goto out;
    }

    if (!query ||
        !g_hash_table_contains (query, "sessionid")) {
      soup_message_set_status (msg, SOUP_STATUS_BAD_REQUEST);
      goto out;
    }

    sessionid = g_hash_table_lookup (query, "sessionid");

    if (!g_hash_table_remove (tables->tokens, sessionid)) {
      soup_message_set_status (msg, SOUP_STATUS_NOT_FOUND);
      goto out;
    }

    if (g_hash_table_contains (tables->ctxs, sessionid))
      /* If there's a stream using this session id, we remove the token,
       * but can't guarantee that the stream will stop. */
      soup_message_set_status (msg, SOUP_STATUS_ACCEPTED);
    else
      soup_message_set_status (msg, SOUP_STATUS_OK);
  }

out:
  return;
}

static void
handle_list_tokens_cb (SoupServer        *server,
                       SoupMessage       *msg,
                       const char        *path,
                       GHashTable        *query,
                       SoupClientContext *client,
                       STPHashTables     *tables)
{
  if (msg->method == SOUP_METHOD_GET) {
    goto GET;
  } else if (g_strcmp0 (path, STP_REST_LIST_TOKENS) != 0) {
    soup_message_set_status (msg, SOUP_STATUS_NOT_FOUND);
    goto out;
  } else if (msg->method == SOUP_METHOD_PUT ||
             msg->method == SOUP_METHOD_POST ||
             msg->method == SOUP_METHOD_DELETE) {
    soup_message_set_status (msg, SOUP_STATUS_METHOD_NOT_ALLOWED);
    goto out;
  } else {
    soup_message_set_status (msg, SOUP_STATUS_NOT_IMPLEMENTED);
    goto out;
  }

GET: {
    gsize length;
    char *response;
    GHashTableIter i;
    JsonBuilder *b;
    JsonNode *dict;
    JsonGenerator *gen;
    gpointer key, value;
    STPStreamToken *token;
    const char *tmp;

    if (!stp_validate_token_server (stp_inet_addrmask, client)) {
      g_debug ("Attempted to access token API from unauthorized host");
      soup_message_set_status (msg, SOUP_STATUS_FORBIDDEN);
      goto out;
    }

    g_hash_table_iter_init (&i, tables->tokens);
    b = json_builder_new ();
    json_builder_begin_array (b);
    while (g_hash_table_iter_next (&i, &key, &value)) {
      token = value;
      json_builder_begin_object (b);

      json_builder_set_member_name (b, "sessionid");
      json_builder_add_string_value (b, key);

      json_builder_set_member_name (b, "udp-clients");
      tmp = token->udp_clients;
      json_builder_add_string_value (b, tmp? tmp : "");

      json_builder_set_member_name (b, "stream-type");
      tmp = stp_get_stream_type_string (token->stream_type);
      json_builder_add_string_value (b, tmp);

      json_builder_end_object (b);
    }
    json_builder_end_array (b);
    dict = json_builder_get_root (b);
    g_object_unref (b);

    gen = json_generator_new ();
    json_generator_set_root (gen, dict);
    json_node_free (dict);

    json_generator_set_pretty (gen, TRUE);
    response = json_generator_to_data (gen, &length);
    g_object_unref (gen);

    soup_message_set_status (msg, SOUP_STATUS_OK);
    soup_message_body_append (msg->response_body,
                              SOUP_MEMORY_TAKE,
                              response, length);
  }
out:
  return;
}

static void
handle_list_streams_cb (SoupServer        *server,
                        SoupMessage       *msg,
                        const char        *path,
                        GHashTable        *query,
                        SoupClientContext *client,
                        STPHashTables     *tables)
{
  if (msg->method == SOUP_METHOD_GET) {
    goto GET;
  } else if (g_strcmp0 (path, STP_REST_LIST_STREAMS) != 0) {
    soup_message_set_status (msg, SOUP_STATUS_NOT_FOUND);
    goto out;
  } else if (msg->method == SOUP_METHOD_PUT ||
             msg->method == SOUP_METHOD_POST ||
             msg->method == SOUP_METHOD_DELETE) {
    soup_message_set_status (msg, SOUP_STATUS_METHOD_NOT_ALLOWED);
    goto out;
  } else {
    soup_message_set_status (msg, SOUP_STATUS_NOT_IMPLEMENTED);
    goto out;
  }

GET: {
    gsize length;
    const char *tmp;
    JsonBuilder *b;
    JsonNode *dict;
    JsonGenerator *gen;
    GHashTableIter i;
    gpointer key, value;
    STPServerCtx *ctx;
    char *sessionid, *response;

    if (!stp_validate_token_server (stp_inet_addrmask, client)) {
      g_debug ("Attempted to access token API from unauthorized host");
      soup_message_set_status (msg, SOUP_STATUS_FORBIDDEN);
      goto out;
    }

    g_hash_table_iter_init (&i, tables->ctxs);
    b = json_builder_new ();
    json_builder_begin_array (b);
    while (g_hash_table_iter_next (&i, &key, &value)) {
      ctx = value;
      sessionid = key;
      json_builder_begin_object (b);

      json_builder_set_member_name (b, "type");
      tmp = stp_get_stream_type_string (ctx->stream_type);
      json_builder_add_string_value (b, tmp);

      json_builder_set_member_name (b, "sessionid");
      json_builder_add_string_value (b, sessionid);

      json_builder_set_member_name (b, "udp-clients");
      tmp = ctx->udp_clients;
      json_builder_add_string_value (b, tmp? tmp : "");

      json_builder_set_member_name (b, "status");
      json_builder_add_string_value (b, ctx->status);

      json_builder_end_object (b);
    }
    json_builder_end_array (b);
    dict = json_builder_get_root (b);
    g_object_unref (b);

    gen = json_generator_new ();
    json_generator_set_root (gen, dict);
    json_node_free (dict);

    json_generator_set_pretty (gen, TRUE);
    response = json_generator_to_data (gen, &length);
    g_object_unref (gen);

    soup_message_set_status (msg, SOUP_STATUS_OK);
    soup_message_body_append (msg->response_body,
                              SOUP_MEMORY_TAKE,
                              response, length);
  }
out:
  return;
}

static void
handle_abort_stream_cb (SoupServer        *server,
                        SoupMessage       *msg,
                        const char        *path,
                        GHashTable        *query,
                        SoupClientContext *client,
                        STPHashTables     *tables)
{
  if (msg->method == SOUP_METHOD_DELETE) {
    goto DELETE;
  } else if (g_strcmp0 (path, STP_REST_ABORT_STREAM) != 0) {
    soup_message_set_status (msg, SOUP_STATUS_NOT_FOUND);
    goto out;
  } else if (msg->method == SOUP_METHOD_PUT ||
             msg->method == SOUP_METHOD_GET ||
             msg->method == SOUP_METHOD_POST) {
    soup_message_set_status (msg, SOUP_STATUS_METHOD_NOT_ALLOWED);
    goto out;
  } else {
    soup_message_set_status (msg, SOUP_STATUS_NOT_IMPLEMENTED);
    goto out;
  }

DELETE: {
    const char *sessionid;
    STPServerCtx *ctx;

    if (!stp_validate_token_server (stp_inet_addrmask, client)) {
      g_debug ("Attempted to access token API from unauthorized host");
      soup_message_set_status (msg, SOUP_STATUS_FORBIDDEN);
      goto out;
    }

    sessionid = g_hash_table_lookup (query, "sessionid");
    if (!sessionid) {
      soup_message_set_status (msg, SOUP_STATUS_BAD_REQUEST);
      goto out;
    }

    ctx = g_hash_table_lookup (tables->ctxs, sessionid);
    if (!ctx) {
      soup_message_set_status (msg, SOUP_STATUS_NOT_FOUND);
      goto out;
    }

    stp_abort_server_ctx (ctx);
    soup_message_set_status (msg, SOUP_STATUS_OK);
  }
out:
  return;
}

gboolean
exit_on_signal_cb (SoupServer *server)
{
  soup_server_disconnect (server);
  g_object_unref (server);
  g_main_loop_quit (loop);
  return G_SOURCE_REMOVE;
}

int
main (int   argc,
      char *argv[])
{
  STPHashTables *tables;
  GOptionContext *optctx;
  GError *error = NULL;

  gst_init (&argc, &argv);

  optctx = g_option_context_new ("- Soup Transcoding Proxy");
  g_option_context_add_main_entries (optctx, entries, NULL);
  g_option_context_add_group (optctx, gst_init_get_option_group ());
  if (!g_option_context_parse (optctx, &argc, &argv, &error)) {
    g_printerr ("Error parsing options: %s\n", error->message);
    return 1;
  }
  g_option_context_free (optctx);

  if (token_server_addrmask) {
    stp_inet_addrmask = g_inet_address_mask_new_from_string (token_server_addrmask,
                                                             &error);
    if (!stp_inet_addrmask) {
      g_printerr ("Error parsing token server address mask: %s\n", error->message);
      return 1;
    }
  }

  tables = g_new0 (STPHashTables, 1);
  /* Keys are paths, and values are STPServerCtxs */
  tables->ctxs = g_hash_table_new_full (g_str_hash, g_str_equal,
                                        (GDestroyNotify)g_free,
                                        (GDestroyNotify)stp_server_ctx_cleanup);
  /* Keys are "session-id:host:port", and there are no values.
   * If host or port are missing, they will be blank. */
  tables->tokens = g_hash_table_new_full (g_str_hash, g_str_equal,
                                          (GDestroyNotify)g_free,
                                          (GDestroyNotify)stp_stream_token_free);

  /* TODO: Accept command-line argument for host */
  server = soup_server_new (SOUP_SERVER_SERVER_HEADER,
                            "soup-transcode-proxy ", NULL);

  /* Handle streaming (chunked) requests when we recv headers */
  soup_server_add_early_handler (server, NULL,
                                 (SoupServerCallback)handle_request_with_headers_cb,
                                 tables, NULL);
  /* Handle completed requests; i.e. the end of POST/PUT and all GET requests */
  soup_server_add_handler (server, NULL,
                           (SoupServerCallback)handle_request_with_body_cb,
                           tables, NULL);

  /* REST API for server status query handling */
  soup_server_add_handler (server, STP_REST_ABORT_STREAM,
                           (SoupServerCallback)handle_abort_stream_cb,
                           tables, NULL);
  soup_server_add_handler (server, STP_REST_LIST_STREAMS,
                           (SoupServerCallback)handle_list_streams_cb,
                           tables, NULL);

  /* REST API for token handling, if requested */
  if (token_server_addrmask) {
    soup_server_add_handler (server, STP_REST_ADD_TOKEN,
                             (SoupServerCallback)handle_add_token_cb,
                             tables, NULL);
    soup_server_add_handler (server, STP_REST_REVOKE_TOKEN,
                             (SoupServerCallback)handle_revoke_token_cb,
                             tables, NULL);
    soup_server_add_handler (server, STP_REST_LIST_TOKENS,
                             (SoupServerCallback)handle_list_tokens_cb,
                             tables, NULL);
  }

  g_unix_signal_add (SIGINT, (GSourceFunc)exit_on_signal_cb, server);

  soup_server_listen_all (server, port, 0, &error);
  if (error) {
    g_printerr ("Error starting soup server: %s\n", error->message);
    return 1;
  }

  g_debug ("SoupServer setup, running mainloop...");
  loop = g_main_loop_new (NULL, FALSE);
  g_main_loop_run (loop);

  g_hash_table_unref (tables->tokens);
  g_hash_table_unref (tables->ctxs);
  g_free (tables);
  return 0;
}