/*
 * builtin_client.c - vpp built-in tcp client/connect code
 *
 * Copyright (c) 2017 by Cisco and/or its affiliates.
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at:
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include <vnet/vnet.h>
#include <vnet/plugin/plugin.h>
#include <vnet/tcp/builtin_client.h>

#include <vlibapi/api.h>
#include <vlibmemory/api.h>
#include <vlibsocket/api.h>
#include <vpp/app/version.h>

/* define message IDs */
#include <vpp/api/vpe_msg_enum.h>

/* define message structures */
#define vl_typedefs
#include <vpp/api/vpe_all_api_h.h>
#undef vl_typedefs

/* define generated endian-swappers */
#define vl_endianfun
#include <vpp/api/vpe_all_api_h.h>
#undef vl_endianfun

/* instantiate all the print functions we know about */
#define vl_print(handle, ...) vlib_cli_output (handle, __VA_ARGS__)
#define vl_printfun
#include <vpp/api/vpe_all_api_h.h>
#undef vl_printfun

static void
send_test_chunk (tclient_main_t * tm, session_t * s)
{
  u8 *test_data = tm->connect_test_data;
  int test_buf_offset;
  u32 bytes_this_chunk;
  session_fifo_event_t evt;
  static int serial_number = 0;
  int rv;

  while (s->bytes_to_send > 0)
    {

      test_buf_offset = s->bytes_sent % vec_len (test_data);
      bytes_this_chunk = vec_len (test_data) - test_buf_offset;

      bytes_this_chunk = bytes_this_chunk < s->bytes_to_send
	? bytes_this_chunk : s->bytes_to_send;

      rv = svm_fifo_enqueue_nowait (s->server_tx_fifo, 0 /*pid */ ,
				    bytes_this_chunk,
				    test_data + test_buf_offset);

      if (rv > 0)
	{
	  s->bytes_to_send -= rv;
	  s->bytes_sent += rv;

	  if (svm_fifo_set_event (s->server_tx_fifo))
	    {
	      /* Fabricate TX event, send to vpp */
	      evt.fifo = s->server_tx_fifo;
	      evt.event_type = FIFO_EVENT_SERVER_TX;
	      evt.event_id = serial_number++;

	      unix_shared_memory_queue_add (tm->vpp_event_queue, (u8 *) & evt,
					    0 /* do wait for mutex */ );
	    }
	}
    }
}

static void
receive_test_chunk (tclient_main_t * tm, session_t * s)
{
  svm_fifo_t *rx_fifo = s->server_rx_fifo;
  int n_read, bytes, i;

  bytes = svm_fifo_max_dequeue (rx_fifo);
  /* Allow enqueuing of new event */
  svm_fifo_unset_event (rx_fifo);

  /* Read the bytes */
  do
    {
      n_read = svm_fifo_dequeue_nowait (rx_fifo, 0, vec_len (tm->rx_buf),
					tm->rx_buf);
      if (n_read > 0)
	{
	  bytes -= n_read;
	  for (i = 0; i < n_read; i++)
	    {
	      if (tm->rx_buf[i] != ((s->bytes_received + i) & 0xff))
		{
		  clib_warning ("read %d error at byte %lld, 0x%x not 0x%x",
				n_read, s->bytes_received + i,
				tm->rx_buf[i],
				((s->bytes_received + i) & 0xff));
		}
	    }
	  s->bytes_to_receive -= n_read;
	  s->bytes_received += n_read;
	}

    }
  while (n_read < 0 || bytes > 0);
}

static void *
tclient_thread_fn (void *arg)
{
  tclient_main_t *tm = &tclient_main;
  vl_api_disconnect_session_t *dmp;
  session_t *sp;
  struct timespec ts, tsrem;
  int i;
  int try_tx, try_rx;
  u32 *session_indices = 0;

  /* stats thread wants no signals. */
  {
    sigset_t s;
    sigfillset (&s);
    pthread_sigmask (SIG_SETMASK, &s, 0);
  }

  while (1)
    {
      /* Wait until we're told to get busy */
      while (tm->run_test == 0
	     || (tm->ready_connections != tm->expected_connections))
	{
	  ts.tv_sec = 0;
	  ts.tv_nsec = 100000000;
	  while (nanosleep (&ts, &tsrem) < 0)
	    ts = tsrem;
	}
      tm->run_test = 0;

      clib_warning ("Run %d iterations", tm->n_iterations);

      for (i = 0; i < tm->n_iterations; i++)
	{
	  session_t *sp;

	  do
	    {
	      try_tx = try_rx = 0;

	      /* *INDENT-OFF* */
	      pool_foreach (sp, tm->sessions, ({
                if (sp->bytes_to_send > 0)
                  {
                    send_test_chunk (tm, sp);
                    try_tx = 1;
                  }
	      }));
	      pool_foreach (sp, tm->sessions, ({
		if (sp->bytes_to_receive > 0)
                  {
                    receive_test_chunk (tm, sp);
                    try_rx = 1;
                  }
              }));
	      /* *INDENT-ON* */

	    }
	  while (try_tx || try_rx);
	}
      clib_warning ("Done %d iterations", tm->n_iterations);

      /* Disconnect sessions... */
      vec_reset_length (session_indices);
      pool_foreach (sp, tm->sessions, (
					{
					vec_add1 (session_indices,
						  sp - tm->sessions);
					}
		    ));

      for (i = 0; i < vec_len (session_indices); i++)
	{
	  sp = pool_elt_at_index (tm->sessions, session_indices[i]);
	  dmp = vl_msg_api_alloc_as_if_client (sizeof (*dmp));
	  memset (dmp, 0, sizeof (*dmp));
	  dmp->_vl_msg_id = ntohs (VL_API_DISCONNECT_SESSION);
	  dmp->client_index = tm->my_client_index;
	  dmp->session_index = sp->vpp_session_index;
	  dmp->session_thread_index = sp->vpp_session_thread;
	  vl_msg_api_send_shmem (tm->vl_input_queue, (u8 *) & dmp);
	  pool_put (tm->sessions, sp);
	}
    }
  /* NOTREACHED */
  return 0;
}

/* So we don't get "no handler for... " msgs */
static void
vl_api_memclnt_create_reply_t_handler (vl_api_memclnt_create_reply_t * mp)
{
  tclient_main_t *tm = &tclient_main;

  tm->my_client_index = mp->index;
}

static void
vl_api_connect_uri_reply_t_handler (vl_api_connect_uri_reply_t * mp)
{
  tclient_main_t *tm = &tclient_main;
  session_t *session;
  u32 session_index;
  u64 key;
  i32 retval = /* clib_net_to_host_u32 ( */ mp->retval /*) */ ;

  if (retval < 0)
    {
      clib_warning ("connection failed: retval %d", retval);
      return;
    }

  tm->our_event_queue = (unix_shared_memory_queue_t *)
    mp->vpp_event_queue_address;

  tm->vpp_event_queue = (unix_shared_memory_queue_t *)
    mp->vpp_event_queue_address;

  /*
   * Setup session
   */
  pool_get (tm->sessions, session);
  memset (session, 0, sizeof (*session));
  session_index = session - tm->sessions;
  session->bytes_to_receive = session->bytes_to_send = tm->bytes_to_send;

  session->server_rx_fifo = (svm_fifo_t *) mp->server_rx_fifo;
  session->server_rx_fifo->client_session_index = session_index;
  session->server_tx_fifo = (svm_fifo_t *) mp->server_tx_fifo;
  session->server_tx_fifo->client_session_index = session_index;

  session->vpp_session_index = mp->session_index;
  session->vpp_session_thread = mp->session_thread_index;

  /* Add it to the session lookup table */
  key = (((u64) mp->session_thread_index) << 32) | (u64) mp->session_index;
  hash_set (tm->session_index_by_vpp_handles, key, session_index);

  tm->ready_connections++;
}

static void
create_api_loopback (tclient_main_t * tm)
{
  vl_api_memclnt_create_t _m, *mp = &_m;
  extern void vl_api_memclnt_create_t_handler (vl_api_memclnt_create_t *);
  api_main_t *am = &api_main;
  vl_shmem_hdr_t *shmem_hdr;

  /*
   * Create a "loopback" API client connection
   * Don't do things like this unless you know what you're doing...
   */

  shmem_hdr = am->shmem_hdr;
  tm->vl_input_queue = shmem_hdr->vl_input_queue;
  memset (mp, 0, sizeof (*mp));
  mp->_vl_msg_id = VL_API_MEMCLNT_CREATE;
  mp->context = 0xFEEDFACE;
  mp->input_queue = (u64) tm->vl_input_queue;
  strncpy ((char *) mp->name, "tcp_tester", sizeof (mp->name) - 1);

  vl_api_memclnt_create_t_handler (mp);
}

#define foreach_tclient_static_api_msg       	\
_(MEMCLNT_CREATE_REPLY, memclnt_create_reply)   \
_(CONNECT_URI_REPLY, connect_uri_reply)

static clib_error_t *
tclient_api_hookup (vlib_main_t * vm)
{
  tclient_main_t *tm = &tclient_main;
  vl_msg_api_msg_config_t _c, *c = &_c;
  int i;

  /* Init test data */
  vec_validate (tm->connect_test_data, 64 * 1024 - 1);
  for (i = 0; i < vec_len (tm->connect_test_data); i++)
    tm->connect_test_data[i] = i & 0xff;

  tm->session_index_by_vpp_handles = hash_create (0, sizeof (uword));
  vec_validate (tm->rx_buf, vec_len (tm->connect_test_data) - 1);

  /* Hook up client-side static APIs to our handlers */
#define _(N,n) do {                                             \
    c->id = VL_API_##N;                                         \
    c->name = #n;                                               \
    c->handler = vl_api_##n##_t_handler;                        \
    c->cleanup = vl_noop_handler;                               \
    c->endian = vl_api_##n##_t_endian;                          \
    c->print = vl_api_##n##_t_print;                            \
    c->size = sizeof(vl_api_##n##_t);                           \
    c->traced = 1; /* trace, so these msgs print */             \
    c->replay = 0; /* don't replay client create/delete msgs */ \
    c->message_bounce = 0; /* don't bounce this message */	\
    vl_msg_api_config(c);} while (0);

  foreach_tclient_static_api_msg;
#undef _

  return 0;
}

VLIB_API_INIT_FUNCTION (tclient_api_hookup);

static clib_error_t *
test_tcp_clients_command_fn (vlib_main_t * vm,
			     unformat_input_t * input,
			     vlib_cli_command_t * cmd)
{
  u8 *connect_uri = (u8 *) "tcp://6.0.1.2/1234";
  u8 *uri;
  tclient_main_t *tm = &tclient_main;
  int i;
  u32 n_clients = 1;

  tm->bytes_to_send = 8192;
  tm->n_iterations = 1;
  vec_free (tm->connect_uri);

  while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
    {
      if (unformat (input, "nclients %d", &n_clients))
	;
      else if (unformat (input, "iterations %d", &tm->n_iterations))
	;
      else if (unformat (input, "bytes %d", &tm->bytes_to_send))
	;
      else if (unformat (input, "uri %s", &tm->connect_uri))
	;
      else
	return clib_error_return (0, "unknown input `%U'",
				  format_unformat_error, input);
    }

  tm->ready_connections = 0;
  tm->expected_connections = n_clients;
  uri = connect_uri;
  if (tm->connect_uri)
    uri = tm->connect_uri;

  create_api_loopback (tm);

  /* Start a transmit thread */
  if (tm->client_thread_handle == 0)
    {
      int rv = pthread_create (&tm->client_thread_handle,
			       NULL /*attr */ , tclient_thread_fn, 0);
      if (rv)
	{
	  tm->client_thread_handle = 0;
	  return clib_error_return (0, "pthread_create returned %d", rv);
	}
    }

  /* Fire off connect requests, in something approaching a normal manner */
  for (i = 0; i < n_clients; i++)
    {
      vl_api_connect_uri_t *cmp;
      cmp = vl_msg_api_alloc_as_if_client (sizeof (*cmp));
      memset (cmp, 0, sizeof (*cmp));

      cmp->_vl_msg_id = ntohs (VL_API_CONNECT_URI);
      cmp->client_index = tm->my_client_index;
      cmp->context = ntohl (0xfeedface);
      memcpy (cmp->uri, uri, strlen ((char *) uri) + 1);
      vl_msg_api_send_shmem (tm->vl_input_queue, (u8 *) & cmp);
    }

  tm->run_test = 1;

  return 0;
}

/* *INDENT-OFF* */
VLIB_CLI_COMMAND (test_clients_command, static) =
{
  .path = "test tcp clients",
  .short_help = "test tcp clients",
  .function = test_tcp_clients_command_fn,
};
/* *INDENT-ON* */

/*
 * fd.io coding-style-patch-verification: ON
 *
 * Local Variables:
 * eval: (c-set-style "gnu")
 * End:
 */