src/plugins/hs_apps/sapi/vpp_echo_proto_quic.c

   1 /*
   2  * Copyright (c) 2019 Cisco and/or its affiliates.
   3  * Licensed under the Apache License, Version 2.0 (the "License");
   4  * you may not use this file except in compliance with the License.
   5  * You may obtain a copy of the License at:
   6  *
   7  *     http://www.apache.org/licenses/LICENSE-2.0
   8  *
   9  * Unless required by applicable law or agreed to in writing, software
  10  * distributed under the License is distributed on an "AS IS" BASIS,
  11  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12  * See the License for the specific language governing permissions and
  13  * limitations under the License.
  14  */
  15
  16 #include <stdio.h>
  17 #include <signal.h>
  18
  19 #include <hs_apps/sapi/vpp_echo_common.h>
  20
  21 typedef struct _quic_echo_cb_vft
  22 {
  23   void (*quic_connected_cb) (session_connected_msg_t * mp, u32 session_index);
  24   void (*client_stream_connected_cb) (session_connected_msg_t * mp,
  25                                       u32 session_index);
  26   void (*server_stream_connected_cb) (session_connected_msg_t * mp,
  27                                       u32 session_index);
  28   void (*quic_accepted_cb) (session_accepted_msg_t * mp, u32 session_index);
  29   void (*client_stream_accepted_cb) (session_accepted_msg_t * mp,
  30                                      u32 session_index);
  31   void (*server_stream_accepted_cb) (session_accepted_msg_t * mp,
  32                                      u32 session_index);
  33 } quic_echo_cb_vft_t;
  34
  35 typedef struct
  36 {
  37   quic_echo_cb_vft_t cb_vft;    /* cb vft for QUIC scenarios */
  38   u8 send_quic_disconnects;     /* actively send disconnect */
  39   u32 n_stream_clients;         /* Target Number of STREAM sessions per QUIC session */
  40   volatile u32 n_quic_clients_connected;        /* Number of connected QUIC sessions */
  41 } quic_echo_proto_main_t;
  42
  43 quic_echo_proto_main_t quic_echo_proto_main;
  44
  45 /*
  46  *
  47  *  ECHO Callback definitions
  48  *
  49  */
  50
  51 static void
  52 quic_echo_on_connected_connect (session_connected_msg_t * mp,
  53                                 u32 session_index)
  54 {
  55   echo_main_t *em = &echo_main;
  56   quic_echo_proto_main_t *eqm = &quic_echo_proto_main;
  57   echo_connect_args_t _a, *a = &_a;
  58   u64 i;
  59
  60   a->parent_session_handle = mp->handle;
  61   a->context = session_index;
  62   clib_memcpy_fast (&a->lcl_ip, &em->lcl_ip, sizeof (ip46_address_t));
  63   clib_memcpy_fast (&a->ip, &em->uri_elts.ip, sizeof (ip46_address_t));
  64
  65   echo_notify_event (em, ECHO_EVT_FIRST_SCONNECT);
  66   for (i = 0; i < eqm->n_stream_clients; i++)
  67     echo_send_rpc (em, echo_send_connect, (echo_rpc_args_t *) a);
  68
  69   ECHO_LOG (1, "Qsession 0x%llx S[%d] connected to %U:%d",
  70             mp->handle, session_index, format_ip46_address, &mp->lcl.ip,
  71             mp->lcl.is_ip4, clib_net_to_host_u16 (mp->lcl.port));
  72 }
  73
  74 static void
  75 quic_echo_on_connected_send (session_connected_msg_t * mp, u32 session_index)
  76 {
  77   static u32 client_index = 0;
  78   echo_main_t *em = &echo_main;
  79   echo_session_t *session;
  80
  81   session = pool_elt_at_index (em->sessions, session_index);
  82   session->bytes_to_send = em->bytes_to_send;
  83   session->bytes_to_receive = em->bytes_to_receive;
  84   session->session_state = ECHO_SESSION_STATE_READY;
  85   em->data_thread_args[client_index++] = session->session_index;
  86 }
  87
  88 static void
  89 quic_echo_on_connected_error (session_connected_msg_t * mp, u32 session_index)
  90 {
  91   ECHO_FAIL (ECHO_FAIL_QUIC_WRONG_CONNECT,
  92              "Got a wrong connected on session %u [%lx]", session_index,
  93              mp->handle);
  94 }
  95
  96 static void
  97 quic_echo_on_accept_recv (session_accepted_msg_t * mp, u32 session_index)
  98 {
  99   static u32 client_index = 0;
 100   echo_main_t *em = &echo_main;
 101   echo_session_t *session;
 102
 103   session = pool_elt_at_index (em->sessions, session_index);
 104   session->bytes_to_send = em->bytes_to_send;
 105   session->bytes_to_receive = em->bytes_to_receive;
 106   em->data_thread_args[client_index++] = session->session_index;
 107   session->session_state = ECHO_SESSION_STATE_READY;
 108 }
 109
 110 static void
 111 quic_echo_on_accept_connect (session_accepted_msg_t * mp, u32 session_index)
 112 {
 113   echo_main_t *em = &echo_main;
 114   quic_echo_proto_main_t *eqm = &quic_echo_proto_main;
 115   ECHO_LOG (2, "Accept on QSession 0x%lx S[%u]", mp->handle, session_index);
 116   echo_connect_args_t _a, *a = &_a;
 117   u32 i;
 118
 119   a->parent_session_handle = mp->handle;
 120   a->context = session_index;
 121   clib_memcpy_fast (&a->lcl_ip, &em->lcl_ip, sizeof (ip46_address_t));
 122   clib_memcpy_fast (&a->ip, &em->uri_elts.ip, sizeof (ip46_address_t));
 123
 124   echo_notify_event (em, ECHO_EVT_FIRST_SCONNECT);
 125   for (i = 0; i < eqm->n_stream_clients; i++)
 126     echo_send_rpc (em, echo_send_connect, (echo_rpc_args_t *) a);
 127 }
 128
 129 static void
 130 quic_echo_on_accept_error (session_accepted_msg_t * mp, u32 session_index)
 131 {
 132   ECHO_FAIL (ECHO_FAIL_QUIC_WRONG_ACCEPT,
 133              "Got a wrong accept on session 0x%lx S[%u]", mp->handle,
 134              session_index);
 135 }
 136
 137 static void
 138 quic_echo_on_accept_log_ip (session_accepted_msg_t * mp, u32 session_index)
 139 {
 140   u8 *ip_str;
 141   ip_str = format (0, "%U", format_ip46_address, &mp->rmt.ip, mp->rmt.is_ip4);
 142   ECHO_LOG (1, "Accepted session from: %s:%d", ip_str,
 143             clib_net_to_host_u16 (mp->rmt.port));
 144
 145 }
 146
 147 static const quic_echo_cb_vft_t default_cb_vft = {
 148   /* Qsessions */
 149   .quic_accepted_cb = quic_echo_on_accept_log_ip,
 150   .quic_connected_cb = quic_echo_on_connected_connect,
 151   /* client initiated streams */
 152   .server_stream_accepted_cb = quic_echo_on_accept_recv,
 153   .client_stream_connected_cb = quic_echo_on_connected_send,
 154   /* server initiated streams */
 155   .client_stream_accepted_cb = quic_echo_on_accept_error,
 156   .server_stream_connected_cb = quic_echo_on_connected_error,
 157 };
 158
 159 static const quic_echo_cb_vft_t server_stream_cb_vft = {
 160   /* Qsessions */
 161   .quic_accepted_cb = quic_echo_on_accept_connect,
 162   .quic_connected_cb = NULL,
 163   /* client initiated streams */
 164   .server_stream_accepted_cb = quic_echo_on_accept_error,
 165   .client_stream_connected_cb = quic_echo_on_connected_error,
 166   /* server initiated streams */
 167   .client_stream_accepted_cb = quic_echo_on_accept_recv,
 168   .server_stream_connected_cb = quic_echo_on_connected_send,
 169 };
 170
 171 static void quic_echo_cleanup_cb (echo_session_t * s, u8 parent_died);
 172
 173 static inline void
 174 quic_echo_cleanup_listener (u32 listener_index, echo_main_t * em,
 175                             quic_echo_proto_main_t * eqm)
 176 {
 177   echo_session_t *ls;
 178   ls = pool_elt_at_index (em->sessions, listener_index);
 179   if (ls->session_type != ECHO_SESSION_TYPE_QUIC)
 180     {
 181       ECHO_LOG (2, "%U: Invalid listener session type",
 182                 echo_format_session, ls);
 183       return;
 184     }
 185   if (!clib_atomic_sub_fetch (&ls->accepted_session_count, 1))
 186     {
 187       if (eqm->send_quic_disconnects == ECHO_CLOSE_F_ACTIVE)
 188         {
 189           echo_send_rpc (em, echo_send_disconnect_session,
 190                          (echo_rpc_args_t *) & ls->vpp_session_handle);
 191           clib_atomic_fetch_add (&em->stats.active_count.q, 1);
 192         }
 193       else if (eqm->send_quic_disconnects == ECHO_CLOSE_F_NONE)
 194         {
 195           quic_echo_cleanup_cb (ls, 0 /* parent_died */ );
 196           clib_atomic_fetch_add (&em->stats.clean_count.q, 1);
 197         }
 198     }
 199 }
 200
 201 static void
 202 quic_echo_cleanup_cb (echo_session_t * s, u8 parent_died)
 203 {
 204   echo_main_t *em = &echo_main;
 205   quic_echo_proto_main_t *eqm = &quic_echo_proto_main;
 206   if ((em->state == STATE_DATA_DONE) ||
 207       !(s->session_state < ECHO_SESSION_STATE_CLOSED))
 208     return;
 209   ECHO_LOG (3, "%U cleanup (parent_died %d)", echo_format_session, s,
 210             parent_died);
 211   s->session_state = ECHO_SESSION_STATE_CLOSED;
 212   if (s->session_type == ECHO_SESSION_TYPE_QUIC)
 213     {
 214       if (parent_died)
 215         clib_atomic_fetch_add (&em->stats.clean_count.q, 1);
 216       /* Don't cleanup listener as it's handled by main() */
 217       clib_atomic_sub_fetch (&eqm->n_quic_clients_connected, 1);
 218     }
 219   else if (s->session_type == ECHO_SESSION_TYPE_STREAM)
 220     {
 221       if (parent_died)
 222         clib_atomic_fetch_add (&em->stats.clean_count.s, 1);
 223       else
 224         quic_echo_cleanup_listener (s->listener_index, em, eqm);
 225       clib_atomic_sub_fetch (&em->n_clients_connected, 1);
 226     }
 227   if (!em->n_clients_connected && !eqm->n_quic_clients_connected)
 228     em->state = STATE_DATA_DONE;
 229   ECHO_LOG (2, "Cleanup sessions (still %uQ %uS): app %U",
 230             eqm->n_quic_clients_connected, em->n_clients_connected,
 231             echo_format_app_state, em->state);
 232 }
 233
 234 static void
 235 quic_echo_initiate_qsession_close_no_stream (echo_main_t * em)
 236 {
 237   quic_echo_proto_main_t *eqm = &quic_echo_proto_main;
 238   ECHO_LOG (2, "Closing Qsessions");
 239   /* Close Quic session without streams */
 240   echo_session_t *s;
 241
 242   pool_foreach (s, em->sessions)
 243    {
 244     if (s->session_type == ECHO_SESSION_TYPE_QUIC)
 245       {
 246         if (eqm->send_quic_disconnects == ECHO_CLOSE_F_ACTIVE)
 247           {
 248             ECHO_LOG (2,"%U: ACTIVE close", echo_format_session, s);
 249             echo_send_rpc (em, echo_send_disconnect_session,
 250                            (echo_rpc_args_t *) &s->vpp_session_handle);
 251             clib_atomic_fetch_add (&em->stats.active_count.q, 1);
 252           }
 253         else if (eqm->send_quic_disconnects == ECHO_CLOSE_F_NONE)
 254           {
 255             ECHO_LOG (2,"%U: CLEAN close", echo_format_session, s);
 256             quic_echo_cleanup_cb (s, 0 /* parent_died */);
 257             clib_atomic_fetch_add (&em->stats.clean_count.q, 1);
 258           }
 259         else
 260           ECHO_LOG (2,"%U: PASSIVE close", echo_format_session, s);
 261       }
 262   }
 263 }
 264
 265 static void
 266 quic_echo_on_connected (session_connected_msg_t * mp, u32 session_index)
 267 {
 268   echo_main_t *em = &echo_main;
 269   quic_echo_proto_main_t *eqm = &quic_echo_proto_main;
 270   echo_session_t *listen_session;
 271   echo_session_t *session = pool_elt_at_index (em->sessions, session_index);
 272
 273   if (session->listener_index == SESSION_INVALID_INDEX)
 274     {
 275       clib_atomic_fetch_add (&em->stats.connected_count.q, 1);
 276       session->session_type = ECHO_SESSION_TYPE_QUIC;
 277       ECHO_LOG (2, "Connected %U -> URI", echo_format_session, session);
 278       session->accepted_session_count = 0;
 279       if (eqm->cb_vft.quic_connected_cb)
 280         eqm->cb_vft.quic_connected_cb (mp, session->session_index);
 281       clib_atomic_fetch_add (&eqm->n_quic_clients_connected, 1);
 282
 283       if (em->stats.connected_count.q % LOGGING_BATCH == 0)
 284         ECHO_LOG (0, "Connected Q %d / %d", em->stats.connected_count.q,
 285                   em->n_connects);
 286     }
 287   else
 288     {
 289       clib_atomic_fetch_add (&em->stats.connected_count.s, 1);
 290       listen_session =
 291         pool_elt_at_index (em->sessions, session->listener_index);
 292       session->session_type = ECHO_SESSION_TYPE_STREAM;
 293       clib_atomic_fetch_add (&listen_session->accepted_session_count, 1);
 294       ECHO_LOG (2, "Connected %U -> %U", echo_format_session, session,
 295                 echo_format_session, listen_session);
 296       if (em->i_am_master && eqm->cb_vft.server_stream_connected_cb)
 297         eqm->cb_vft.server_stream_connected_cb (mp, session->session_index);
 298       if (!em->i_am_master && eqm->cb_vft.client_stream_connected_cb)
 299         eqm->cb_vft.client_stream_connected_cb (mp, session->session_index);
 300       clib_atomic_fetch_add (&em->n_clients_connected, 1);
 301
 302       if (em->stats.connected_count.s % LOGGING_BATCH == 0)
 303         ECHO_LOG (0, "Connected S %d / %d", em->stats.connected_count.s,
 304                   em->n_clients);
 305     }
 306
 307
 308   if (em->n_clients_connected == em->n_clients
 309       && em->n_clients_connected != 0)
 310     echo_notify_event (em, ECHO_EVT_LAST_SCONNECTED);
 311
 312   if (eqm->n_quic_clients_connected == em->n_connects
 313       && em->state < STATE_READY)
 314     {
 315       echo_notify_event (em, ECHO_EVT_LAST_QCONNECTED);
 316       em->state = STATE_READY;
 317       if (eqm->n_stream_clients == 0)
 318         quic_echo_initiate_qsession_close_no_stream (em);
 319     }
 320 }
 321
 322 static void
 323 quic_echo_connected_cb (session_connected_bundled_msg_t * mp,
 324                         u32 session_index, u8 is_failed)
 325 {
 326   if (is_failed)
 327     {
 328       ECHO_FAIL (ECHO_FAIL_QUIC_WRONG_CONNECT, "Echo connect failed");
 329       return;
 330     }
 331   return quic_echo_on_connected ((session_connected_msg_t *) mp,
 332                                  session_index);
 333 }
 334
 335 static void
 336 quic_echo_accepted_cb (session_accepted_msg_t * mp, echo_session_t * session)
 337 {
 338   echo_main_t *em = &echo_main;
 339   quic_echo_proto_main_t *eqm = &quic_echo_proto_main;
 340   echo_session_t *ls;
 341   ls = pool_elt_at_index (em->sessions, session->listener_index);
 342   if (ls->session_type == ECHO_SESSION_TYPE_LISTEN)
 343     {
 344       clib_atomic_fetch_add (&em->stats.accepted_count.q, 1);
 345       echo_notify_event (em, ECHO_EVT_FIRST_QCONNECT);
 346       session->session_type = ECHO_SESSION_TYPE_QUIC;
 347       session->accepted_session_count = 0;
 348       if (eqm->cb_vft.quic_accepted_cb)
 349         eqm->cb_vft.quic_accepted_cb (mp, session->session_index);
 350       clib_atomic_fetch_add (&eqm->n_quic_clients_connected, 1);
 351
 352       if (em->stats.accepted_count.q % LOGGING_BATCH == 0)
 353         ECHO_LOG (0, "Accepted Q %d / %d", em->stats.accepted_count.q,
 354                   em->n_connects);
 355     }
 356   else
 357     {
 358       clib_atomic_fetch_add (&em->stats.accepted_count.s, 1);
 359       session->session_type = ECHO_SESSION_TYPE_STREAM;
 360       echo_notify_event (em, ECHO_EVT_FIRST_SCONNECT);
 361       clib_atomic_fetch_add (&ls->accepted_session_count, 1);
 362       if (em->i_am_master && eqm->cb_vft.server_stream_accepted_cb)
 363         eqm->cb_vft.server_stream_accepted_cb (mp, session->session_index);
 364       if (!em->i_am_master && eqm->cb_vft.client_stream_accepted_cb)
 365         eqm->cb_vft.client_stream_accepted_cb (mp, session->session_index);
 366       clib_atomic_fetch_add (&em->n_clients_connected, 1);
 367
 368       if (em->stats.accepted_count.s % LOGGING_BATCH == 0)
 369         ECHO_LOG (0, "Accepted S %d / %d", em->stats.accepted_count.s,
 370                   em->n_clients);
 371
 372       if (em->connect_flag && !(mp->flags & em->connect_flag))
 373         {
 374           ECHO_FAIL (ECHO_FAIL_UNIDIRECTIONAL,
 375                      "expected unidirectional streams");
 376         }
 377     }
 378
 379   if (em->n_clients_connected == em->n_clients
 380       && em->n_clients_connected != 0)
 381     echo_notify_event (em, ECHO_EVT_LAST_SCONNECTED);
 382
 383   if (eqm->n_quic_clients_connected == em->n_connects
 384       && em->state < STATE_READY)
 385     {
 386       echo_notify_event (em, ECHO_EVT_LAST_QCONNECTED);
 387       em->state = STATE_READY;
 388       if (eqm->n_stream_clients == 0)
 389         quic_echo_initiate_qsession_close_no_stream (em);
 390     }
 391 }
 392
 393 static void
 394 quic_echo_sent_disconnect_cb (echo_session_t * s)
 395 {
 396   if (s->session_type == ECHO_SESSION_TYPE_STREAM)
 397     s->session_state = ECHO_SESSION_STATE_CLOSING;
 398   else
 399     quic_echo_cleanup_cb (s, 0 /* parent_died */ );     /* We can clean Q/Lsessions right away */
 400 }
 401
 402 static void
 403 quic_echo_disconnected_cb (session_disconnected_msg_t * mp,
 404                            echo_session_t * s)
 405 {
 406   echo_main_t *em = &echo_main;
 407   if (s->session_type == ECHO_SESSION_TYPE_STREAM)
 408     {
 409       echo_session_print_stats (em, s);
 410       if (s->bytes_to_receive || s->bytes_to_send)
 411         s->session_state = ECHO_SESSION_STATE_AWAIT_DATA;
 412       else
 413         s->session_state = ECHO_SESSION_STATE_CLOSING;
 414       clib_atomic_fetch_add (&em->stats.close_count.s, 1);
 415     }
 416   else
 417     {
 418       quic_echo_cleanup_cb (s, 0 /* parent_died */ );   /* We can clean Q/Lsessions right away */
 419       clib_atomic_fetch_add (&em->stats.close_count.q, 1);
 420     }
 421 }
 422
 423 static void
 424 quic_echo_reset_cb (session_reset_msg_t * mp, echo_session_t * s)
 425 {
 426   echo_main_t *em = &echo_main;
 427   if (s->session_type == ECHO_SESSION_TYPE_STREAM)
 428     {
 429       clib_atomic_fetch_add (&em->stats.reset_count.s, 1);
 430       s->session_state = ECHO_SESSION_STATE_CLOSING;
 431     }
 432   else
 433     {
 434       clib_atomic_fetch_add (&em->stats.reset_count.q, 1);
 435       quic_echo_cleanup_cb (s, 0 /* parent_died */ );   /* We can clean Q/Lsessions right away */
 436     }
 437 }
 438
 439 static uword
 440 quic_echo_unformat_setup_vft (unformat_input_t * input, va_list * args)
 441 {
 442   quic_echo_proto_main_t *eqm = &quic_echo_proto_main;
 443   if (unformat (input, "serverstream"))
 444     eqm->cb_vft = server_stream_cb_vft;
 445   else if (unformat (input, "default"))
 446     ;
 447   else
 448     return 0;
 449   return 1;
 450 }
 451
 452 static int
 453 quic_echo_process_opts_cb (unformat_input_t * a)
 454 {
 455   echo_main_t *em = &echo_main;
 456   quic_echo_proto_main_t *eqm = &quic_echo_proto_main;
 457   if (unformat (a, "quic-streams %d", &eqm->n_stream_clients))
 458     ;
 459   else if (unformat (a, "quic-setup %U", quic_echo_unformat_setup_vft))
 460     ;
 461   else if (unformat (a, "uni"))
 462     em->connect_flag = TRANSPORT_CFG_F_UNIDIRECTIONAL;
 463   else if (unformat (a, "qclose=%U",
 464                      echo_unformat_close, &eqm->send_quic_disconnects))
 465     ;
 466   else
 467     return 0;
 468   return 1;
 469 }
 470
 471 static void
 472 quic_echo_set_defaults_before_opts_cb ()
 473 {
 474   quic_echo_proto_main_t *eqm = &quic_echo_proto_main;
 475   eqm->cb_vft = default_cb_vft;
 476   eqm->n_stream_clients = 1;
 477 }
 478
 479 static void
 480 quic_echo_set_defaults_after_opts_cb ()
 481 {
 482   quic_echo_proto_main_t *eqm = &quic_echo_proto_main;
 483   echo_main_t *em = &echo_main;
 484   u8 default_f_active;
 485
 486   em->n_connects = em->n_clients;
 487   em->n_sessions =
 488     clib_max (1,
 489               eqm->n_stream_clients) * em->n_clients + em->n_clients +
 490     em->n_uris;
 491   em->n_clients = eqm->n_stream_clients * em->n_clients;
 492
 493   if (em->i_am_master)
 494     default_f_active =
 495       em->bytes_to_send == 0 ? ECHO_CLOSE_F_ACTIVE : ECHO_CLOSE_F_PASSIVE;
 496   else
 497     default_f_active =
 498       em->bytes_to_receive == 0 ? ECHO_CLOSE_F_PASSIVE : ECHO_CLOSE_F_ACTIVE;
 499   if (eqm->send_quic_disconnects == ECHO_CLOSE_F_INVALID)
 500     eqm->send_quic_disconnects = default_f_active;
 501 }
 502
 503 static void
 504 quic_echo_print_usage_cb ()
 505 {
 506   fprintf (stderr,
 507            "-- QUIC specific options -- \n"
 508            "  quic-setup OPT      OPT=serverstream : Client open N connections. \n"
 509            "                       On each one server opens M streams\n"
 510            "                      OPT=default : Client open N connections.\n"
 511            "                       On each one client opens M streams\n"
 512            "  qclose=[Y|N|W]      When connection is done send[Y]|nop[N]|wait[W] for close\n"
 513            "  uni                 Use unidirectional streams\n"
 514            "\n"
 515            "  quic-streams N      Open N QUIC streams (defaults to 1)\n");
 516 }
 517
 518 echo_proto_cb_vft_t quic_echo_proto_cb_vft = {
 519   .disconnected_cb = quic_echo_disconnected_cb,
 520   .connected_cb = quic_echo_connected_cb,
 521   .accepted_cb = quic_echo_accepted_cb,
 522   .reset_cb = quic_echo_reset_cb,
 523   .sent_disconnect_cb = quic_echo_sent_disconnect_cb,
 524   .cleanup_cb = quic_echo_cleanup_cb,
 525   .process_opts_cb = quic_echo_process_opts_cb,
 526   .print_usage_cb = quic_echo_print_usage_cb,
 527   .set_defaults_before_opts_cb = quic_echo_set_defaults_before_opts_cb,
 528   .set_defaults_after_opts_cb = quic_echo_set_defaults_after_opts_cb,
 529 };
 530
 531 ECHO_REGISTER_PROTO (TRANSPORT_PROTO_QUIC, quic_echo_proto_cb_vft);
 532
 533 /*
 534  * fd.io coding-style-patch-verification: ON
 535  *
 536  * Local Variables:
 537  * eval: (c-set-style "gnu")
 538  * End:
 539  */