src/vnet/tcp/builtin_http_server.c - fdio/vpp - Gitiles

 /*
 * Copyright (c) 2015-2017 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/session/application.h>
 #include <vnet/session/application_interface.h>

 typedef enum
 {
   EVENT_WAKEUP = 1,
 } http_process_event_t;

 typedef struct
 {
   u64 session_handle;
   u64 node_index;
   u8 *data;
 } builtin_http_server_args;

 typedef struct
 {
   u8 *rx_buf;
   unix_shared_memory_queue_t **vpp_queue;
   u64 byte_index;

   uword *handler_by_get_request;

   u32 *free_http_cli_process_node_indices;

   /* Sever's event queue */
   unix_shared_memory_queue_t *vl_input_queue;

   /* API client handle */
   u32 my_client_index;

   u32 app_index;

   /* process node index for evnt scheduling */
   u32 node_index;
   vlib_main_t *vlib_main;
 } http_server_main_t;

 http_server_main_t http_server_main;

 static void
 free_http_process (builtin_http_server_args * args)
 {
   vlib_node_runtime_t *rt;
   vlib_main_t *vm = &vlib_global_main;
   http_server_main_t *hsm = &http_server_main;
   vlib_node_t *n;
   u32 node_index;
   builtin_http_server_args **save_args;

   node_index = args->node_index;
   ASSERT (node_index != 0);

   n = vlib_get_node (vm, node_index);
   rt = vlib_node_get_runtime (vm, n->index);
   save_args = vlib_node_get_runtime_data (vm, n->index);

   /* Reset process session pointer */
   clib_mem_free (*save_args);
   *save_args = 0;

   /* Turn off the process node */
   vlib_node_set_state (vm, rt->node_index, VLIB_NODE_STATE_DISABLED);

   /* add node index to the freelist */
   vec_add1 (hsm->free_http_cli_process_node_indices, node_index);
 }

 static const char
   *http_response = "HTTP/1.1 200 OK\r\n"
   "Content-Type: text/html\r\n"
   "Expires: Mon, 11 Jan 1970 10:10:10 GMT\r\n"
   "Connection: close\r\n"
   "Pragma: no-cache\r\n" "Content-Length: %d\r\n\r\n%s";

 static const char
   *http_error_template = "HTTP/1.1 %s\r\n"
   "Content-Type: text/html\r\n"
   "Expires: Mon, 11 Jan 1970 10:10:10 GMT\r\n"
   "Connection: close\r\n" "Pragma: no-cache\r\n" "Content-Length: 0\r\n\r\n";

 /* Header, including incantation to suppress favicon.ico requests */
 static const char
   *html_header_template = "<html><head><title>%v</title>"
   "</head><link rel=\"icon\" href=\"data:,\"><body><pre>";

 static const char *html_footer = "</pre></body></html>\r\n";

 static void
 http_cli_output (uword arg, u8 * buffer, uword buffer_bytes)
 {
   u8 **output_vecp = (u8 **) arg;
   u8 *output_vec;
   u32 offset;

   output_vec = *output_vecp;

   offset = vec_len (output_vec);
   vec_validate (output_vec, offset + buffer_bytes - 1);
   clib_memcpy (output_vec + offset, buffer, buffer_bytes);

   *output_vecp = output_vec;
 }

 void
 send_data (builtin_http_server_args * args, u8 * data)
 {
   session_fifo_event_t evt;
   u32 offset, bytes_to_send;
   f64 delay = 10e-3;
   http_server_main_t *hsm = &http_server_main;
   vlib_main_t *vm = hsm->vlib_main;
   f64 last_sent_timer = vlib_time_now (vm);
   stream_session_t *s;

   s = stream_session_get_from_handle (args->session_handle);
   ASSERT (s);
   bytes_to_send = vec_len (data);
   offset = 0;

   while (bytes_to_send > 0)
     {
       int actual_transfer;

       actual_transfer = svm_fifo_enqueue_nowait
 	(s->server_tx_fifo, bytes_to_send, data + offset);

       /* Made any progress? */
       if (actual_transfer <= 0)
 	{
 	  vlib_process_suspend (vm, delay);
 	  /* 10s deadman timer */
 	  if (vlib_time_now (vm) > last_sent_timer + 10.0)
 	    {
 	      /* $$$$ FC: reset transport session here? */
 	      break;
 	    }
 	  /* Exponential backoff, within reason */
 	  if (delay < 1.0)
 	    delay = delay * 2.0;
 	}
       else
 	{
 	  last_sent_timer = vlib_time_now (vm);
 	  offset += actual_transfer;
 	  bytes_to_send -= actual_transfer;

 	  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_APP_TX;
 	      evt.event_id = 0;

 	      unix_shared_memory_queue_add (hsm->vpp_queue[s->thread_index],
 					    (u8 *) & evt,
 					    0 /* do wait for mutex */ );
 	    }
 	  delay = 10e-3;
 	}
     }
 }

 static void
 send_error (builtin_http_server_args * args, char *str)
 {
   u8 *data;

   data = format (0, http_error_template, str);
   send_data (args, data);
   vec_free (data);
 }

 static uword
 http_cli_process (vlib_main_t * vm,
 		  vlib_node_runtime_t * rt, vlib_frame_t * f)
 {
   http_server_main_t *hsm = &http_server_main;
   u8 *request = 0, *reply = 0;
   builtin_http_server_args **save_args;
   builtin_http_server_args *args;
   unformat_input_t input;
   int i;
   u8 *http = 0, *html = 0;

   save_args = vlib_node_get_runtime_data (hsm->vlib_main, rt->node_index);
   args = *save_args;

   request = (u8 *) (void *) (args->data);
   if (vec_len (request) < 7)
     {
       send_error (args, "400 Bad Request");
       goto out;
     }

   for (i = 0; i < vec_len (request) - 4; i++)
     {
       if (request[i] == 'G' &&
 	  request[i + 1] == 'E' &&
 	  request[i + 2] == 'T' && request[i + 3] == ' ')
 	goto found;
     }
 bad_request:
   send_error (args, "400 Bad Request");
   goto out;

 found:
   /* Lose "GET " */
   vec_delete (request, i + 5, 0);

   /* Replace slashes with spaces, stop at the end of the path */
   i = 0;
   while (1)
     {
       if (request[i] == '/')
 	request[i] = ' ';
       else if (request[i] == ' ')
 	{
 	  /* vlib_cli_input is vector-based, no need for a NULL */
 	  _vec_len (request) = i;
 	  break;
 	}
       i++;
       /* Should never happen */
       if (i == vec_len (request))
 	goto bad_request;
     }

   /* Generate the html header */
   html = format (0, html_header_template, request /* title */ );

   /* Run the command */
   unformat_init_vector (&input, request);
   vlib_cli_input (vm, &input, http_cli_output, (uword) & reply);
   unformat_free (&input);
   request = 0;

   /* Generate the html page */
   html = format (html, "%v", reply);
   html = format (html, html_footer);
   /* And the http reply */
   http = format (0, http_response, vec_len (html), html);

   /* Send it */
   send_data (args, http);

 out:
   /* Cleanup */
   vec_free (request);
   vec_free (reply);
   vec_free (html);
   vec_free (http);

   free_http_process (args);
   return (0);
 }

 static void
 alloc_http_process (builtin_http_server_args * args)
 {
   char *name;
   vlib_node_t *n;
   http_server_main_t *hsm = &http_server_main;
   vlib_main_t *vm = hsm->vlib_main;
   uword l = vec_len (hsm->free_http_cli_process_node_indices);
   builtin_http_server_args **save_args;

   if (vec_len (hsm->free_http_cli_process_node_indices) > 0)
     {
       n = vlib_get_node (vm, hsm->free_http_cli_process_node_indices[l - 1]);
       vlib_node_set_state (vm, n->index, VLIB_NODE_STATE_POLLING);
       _vec_len (hsm->free_http_cli_process_node_indices) = l - 1;
     }
   else
     {
       static vlib_node_registration_t r = {
 	.function = http_cli_process,
 	.type = VLIB_NODE_TYPE_PROCESS,
 	.process_log2_n_stack_bytes = 16,
 	.runtime_data_bytes = sizeof (void *),
       };

       name = (char *) format (0, "http-cli-%d", l);
       r.name = name;
       vlib_register_node (vm, &r);
       vec_free (name);

       n = vlib_get_node (vm, r.index);
     }

   /* Save the node index in the args. It won't be zero. */
   args->node_index = n->index;

   /* Save the args (pointer) in the node runtime */
   save_args = vlib_node_get_runtime_data (vm, n->index);
   *save_args = args;

   vlib_start_process (vm, n->runtime_index);
 }

 static void
 alloc_http_process_callback (void *cb_args)
 {
   alloc_http_process ((builtin_http_server_args *) cb_args);
 }

 static int
 http_server_rx_callback (stream_session_t * s)
 {
   u32 max_dequeue;
   int actual_transfer;
   http_server_main_t *hsm = &http_server_main;
   svm_fifo_t *rx_fifo;
   builtin_http_server_args *args;

   rx_fifo = s->server_rx_fifo;
   max_dequeue = svm_fifo_max_dequeue (rx_fifo);
   svm_fifo_unset_event (rx_fifo);
   if (PREDICT_FALSE (max_dequeue == 0))
     return 0;

   vec_validate (hsm->rx_buf, max_dequeue - 1);
   _vec_len (hsm->rx_buf) = max_dequeue;

   actual_transfer = svm_fifo_dequeue_nowait (rx_fifo, max_dequeue,
 					     hsm->rx_buf);
   ASSERT (actual_transfer > 0);
   _vec_len (hsm->rx_buf) = actual_transfer;

   /* send the command to a new/recycled vlib process */
   args = clib_mem_alloc (sizeof (*args));
   args->data = vec_dup (hsm->rx_buf);
   args->session_handle = stream_session_handle (s);

   /* Send an RPC request via the thread-0 input node */
   if (vlib_get_thread_index () != 0)
     {
       session_fifo_event_t evt;
       evt.rpc_args.fp = alloc_http_process_callback;
       evt.rpc_args.arg = args;
       evt.event_type = FIFO_EVENT_RPC;
       unix_shared_memory_queue_add
 	(session_manager_get_vpp_event_queue (0 /* main thread */ ),
 	 (u8 *) & evt, 0 /* do wait for mutex */ );
     }
   else
     alloc_http_process (args);
   return 0;
 }

 static int
 builtin_session_accept_callback (stream_session_t * s)
 {
   http_server_main_t *bsm = &http_server_main;

   bsm->vpp_queue[s->thread_index] =
     session_manager_get_vpp_event_queue (s->thread_index);
   s->session_state = SESSION_STATE_READY;
   bsm->byte_index = 0;
   return 0;
 }

 static void
 builtin_session_disconnect_callback (stream_session_t * s)
 {
   http_server_main_t *bsm = &http_server_main;
   vnet_disconnect_args_t _a, *a = &_a;

   a->handle = stream_session_handle (s);
   a->app_index = bsm->app_index;
   vnet_disconnect_session (a);
 }

 static void
 builtin_session_reset_callback (stream_session_t * s)
 {
   clib_warning ("called.. ");

   stream_session_cleanup (s);
 }

 static int
 builtin_session_connected_callback (u32 app_index, u32 api_context,
 				    stream_session_t * s, u8 is_fail)
 {
   clib_warning ("called...");
   return -1;
 }

 static int
 builtin_add_segment_callback (u32 client_index,
 			      const u8 * seg_name, u32 seg_size)
 {
   clib_warning ("called...");
   return -1;
 }

 static int
 builtin_redirect_connect_callback (u32 client_index, void *mp)
 {
   clib_warning ("called...");
   return -1;
 }

 static session_cb_vft_t builtin_session_cb_vft = {
   .session_accept_callback = builtin_session_accept_callback,
   .session_disconnect_callback = builtin_session_disconnect_callback,
   .session_connected_callback = builtin_session_connected_callback,
   .add_segment_callback = builtin_add_segment_callback,
   .redirect_connect_callback = builtin_redirect_connect_callback,
   .builtin_server_rx_callback = http_server_rx_callback,
   .session_reset_callback = builtin_session_reset_callback
 };

 /* Abuse VPP's input queue */
 static int
 create_api_loopback (vlib_main_t * vm)
 {
   http_server_main_t *hsm = &http_server_main;
   api_main_t *am = &api_main;
   vl_shmem_hdr_t *shmem_hdr;

   shmem_hdr = am->shmem_hdr;
   hsm->vl_input_queue = shmem_hdr->vl_input_queue;
   hsm->my_client_index =
     vl_api_memclnt_create_internal ("tcp_test_client", hsm->vl_input_queue);
   return 0;
 }

 static int
 server_attach ()
 {
   http_server_main_t *hsm = &http_server_main;
   u8 segment_name[128];
   u64 options[SESSION_OPTIONS_N_OPTIONS];
   vnet_app_attach_args_t _a, *a = &_a;

   memset (a, 0, sizeof (*a));
   memset (options, 0, sizeof (options));

   a->api_client_index = hsm->my_client_index;
   a->session_cb_vft = &builtin_session_cb_vft;
   a->options = options;
   a->options[SESSION_OPTIONS_SEGMENT_SIZE] = 128 << 20;
   a->options[SESSION_OPTIONS_RX_FIFO_SIZE] = 8 << 10;
   a->options[SESSION_OPTIONS_TX_FIFO_SIZE] = 32 << 10;
   a->options[APP_OPTIONS_FLAGS] = APP_OPTIONS_FLAGS_BUILTIN_APP;
   a->options[APP_OPTIONS_PREALLOC_FIFO_PAIRS] = 16;
   a->segment_name = segment_name;
   a->segment_name_length = ARRAY_LEN (segment_name);

   if (vnet_application_attach (a))
     {
       clib_warning ("failed to attach server");
       return -1;
     }
   hsm->app_index = a->app_index;
   return 0;
 }

 static int
 server_listen ()
 {
   http_server_main_t *hsm = &http_server_main;
   vnet_bind_args_t _a, *a = &_a;
   memset (a, 0, sizeof (*a));
   a->app_index = hsm->app_index;
   a->uri = "tcp://0.0.0.0/80";
   return vnet_bind_uri (a);
 }

 static int
 server_create (vlib_main_t * vm)
 {
   http_server_main_t *hsm = &http_server_main;
   u32 num_threads;
   vlib_thread_main_t *vtm = vlib_get_thread_main ();

   ASSERT (hsm->my_client_index == (u32) ~ 0);
   if (create_api_loopback (vm))
     return -1;

   num_threads = 1 /* main thread */  + vtm->n_threads;
   vec_validate (http_server_main.vpp_queue, num_threads - 1);

   if (server_attach ())
     {
       clib_warning ("failed to attach server");
       return -1;
     }
   if (server_listen ())
     {
       clib_warning ("failed to start listening");
       return -1;
     }
   return 0;
 }

 static clib_error_t *
 server_create_command_fn (vlib_main_t * vm,
 			  unformat_input_t * input, vlib_cli_command_t * cmd)
 {
   http_server_main_t *hsm = &http_server_main;
   int rv;

   if (hsm->my_client_index != (u32) ~ 0)
     return clib_error_return (0, "test http server is already running");

   vnet_session_enable_disable (vm, 1 /* turn on TCP, etc. */ );
   rv = server_create (vm);
   switch (rv)
     {
     case 0:
       break;
     default:
       return clib_error_return (0, "server_create returned %d", rv);
     }
   return 0;
 }

 /* *INDENT-OFF* */
 VLIB_CLI_COMMAND (server_create_command, static) =
 {
   .path = "test http server",
   .short_help = "test http server",
   .function = server_create_command_fn,
 };
 /* *INDENT-ON* */

 static clib_error_t *
 builtin_http_server_main_init (vlib_main_t * vm)
 {
   http_server_main_t *hsm = &http_server_main;
   hsm->my_client_index = ~0;
   hsm->vlib_main = vm;

   return 0;
 }

 VLIB_INIT_FUNCTION (builtin_http_server_main_init);

 /*
 * fd.io coding-style-patch-verification: ON
 *
 * Local Variables:
 * eval: (c-set-style "gnu")
 * End:
 */
	/*
	* Copyright (c) 2015-2017 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/session/application.h>
	#include <vnet/session/application_interface.h>

	typedef enum
	{
	EVENT_WAKEUP = 1,
	} http_process_event_t;

	typedef struct
	{
	u64 session_handle;
	u64 node_index;
	u8 *data;
	} builtin_http_server_args;

	typedef struct
	{
	u8 *rx_buf;
	unix_shared_memory_queue_t **vpp_queue;
	u64 byte_index;

	uword *handler_by_get_request;

	u32 *free_http_cli_process_node_indices;

	/* Sever's event queue */
	unix_shared_memory_queue_t *vl_input_queue;

	/* API client handle */
	u32 my_client_index;

	u32 app_index;

	/* process node index for evnt scheduling */
	u32 node_index;
	vlib_main_t *vlib_main;
	} http_server_main_t;

	http_server_main_t http_server_main;

	static void
	free_http_process (builtin_http_server_args * args)
	{
	vlib_node_runtime_t *rt;
	vlib_main_t *vm = &vlib_global_main;
	http_server_main_t *hsm = &http_server_main;
	vlib_node_t *n;
	u32 node_index;
	builtin_http_server_args **save_args;

	node_index = args->node_index;
	ASSERT (node_index != 0);

	n = vlib_get_node (vm, node_index);
	rt = vlib_node_get_runtime (vm, n->index);
	save_args = vlib_node_get_runtime_data (vm, n->index);

	/* Reset process session pointer */
	clib_mem_free (*save_args);
	*save_args = 0;

	/* Turn off the process node */
	vlib_node_set_state (vm, rt->node_index, VLIB_NODE_STATE_DISABLED);

	/* add node index to the freelist */
	vec_add1 (hsm->free_http_cli_process_node_indices, node_index);
	}

	static const char
	*http_response = "HTTP/1.1 200 OK\r\n"
	"Content-Type: text/html\r\n"
	"Expires: Mon, 11 Jan 1970 10:10:10 GMT\r\n"
	"Connection: close\r\n"
	"Pragma: no-cache\r\n" "Content-Length: %d\r\n\r\n%s";

	static const char
	*http_error_template = "HTTP/1.1 %s\r\n"
	"Content-Type: text/html\r\n"
	"Expires: Mon, 11 Jan 1970 10:10:10 GMT\r\n"
	"Connection: close\r\n" "Pragma: no-cache\r\n" "Content-Length: 0\r\n\r\n";

	/* Header, including incantation to suppress favicon.ico requests */
	static const char
	*html_header_template = "<html><head><title>%v</title>"
	"</head><link rel=\"icon\" href=\"data:,\"><body><pre>";

	static const char *html_footer = "</pre></body></html>\r\n";

	static void
	http_cli_output (uword arg, u8 * buffer, uword buffer_bytes)
	{
	u8 output_vecp = (u8 ) arg;
	u8 *output_vec;
	u32 offset;

	output_vec = *output_vecp;

	offset = vec_len (output_vec);
	vec_validate (output_vec, offset + buffer_bytes - 1);
	clib_memcpy (output_vec + offset, buffer, buffer_bytes);

	*output_vecp = output_vec;
	}

	void
	send_data (builtin_http_server_args * args, u8 * data)
	{
	session_fifo_event_t evt;
	u32 offset, bytes_to_send;
	f64 delay = 10e-3;
	http_server_main_t *hsm = &http_server_main;
	vlib_main_t *vm = hsm->vlib_main;
	f64 last_sent_timer = vlib_time_now (vm);
	stream_session_t *s;

	s = stream_session_get_from_handle (args->session_handle);
	ASSERT (s);
	bytes_to_send = vec_len (data);
	offset = 0;

	while (bytes_to_send > 0)
	{
	int actual_transfer;

	actual_transfer = svm_fifo_enqueue_nowait
	(s->server_tx_fifo, bytes_to_send, data + offset);

	/* Made any progress? */
	if (actual_transfer <= 0)
	{
	vlib_process_suspend (vm, delay);
	/* 10s deadman timer */
	if (vlib_time_now (vm) > last_sent_timer + 10.0)
	{
	/* $$$$ FC: reset transport session here? */
	break;
	}
	/* Exponential backoff, within reason */
	if (delay < 1.0)
	delay = delay * 2.0;
	}
	else
	{
	last_sent_timer = vlib_time_now (vm);
	offset += actual_transfer;
	bytes_to_send -= actual_transfer;

	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_APP_TX;
	evt.event_id = 0;

	unix_shared_memory_queue_add (hsm->vpp_queue[s->thread_index],
	(u8 *) & evt,
	0 /* do wait for mutex */ );
	}
	delay = 10e-3;
	}
	}
	}

	static void
	send_error (builtin_http_server_args * args, char *str)
	{
	u8 *data;

	data = format (0, http_error_template, str);
	send_data (args, data);
	vec_free (data);
	}

	static uword
	http_cli_process (vlib_main_t * vm,
	vlib_node_runtime_t * rt, vlib_frame_t * f)
	{
	http_server_main_t *hsm = &http_server_main;
	u8 request = 0, reply = 0;
	builtin_http_server_args **save_args;
	builtin_http_server_args *args;
	unformat_input_t input;
	int i;
	u8 http = 0, html = 0;

	save_args = vlib_node_get_runtime_data (hsm->vlib_main, rt->node_index);
	args = *save_args;

	request = (u8 ) (void ) (args->data);
	if (vec_len (request) < 7)
	{
	send_error (args, "400 Bad Request");
	goto out;
	}

	for (i = 0; i < vec_len (request) - 4; i++)
	{
	if (request[i] == 'G' &&
	request[i + 1] == 'E' &&
	request[i + 2] == 'T' && request[i + 3] == ' ')
	goto found;
	}
	bad_request:
	send_error (args, "400 Bad Request");
	goto out;

	found:
	/* Lose "GET " */
	vec_delete (request, i + 5, 0);

	/* Replace slashes with spaces, stop at the end of the path */
	i = 0;
	while (1)
	{
	if (request[i] == '/')
	request[i] = ' ';
	else if (request[i] == ' ')
	{
	/* vlib_cli_input is vector-based, no need for a NULL */
	_vec_len (request) = i;
	break;
	}
	i++;
	/* Should never happen */
	if (i == vec_len (request))
	goto bad_request;
	}

	/* Generate the html header */
	html = format (0, html_header_template, request /* title */ );

	/* Run the command */
	unformat_init_vector (&input, request);
	vlib_cli_input (vm, &input, http_cli_output, (uword) & reply);
	unformat_free (&input);
	request = 0;

	/* Generate the html page */
	html = format (html, "%v", reply);
	html = format (html, html_footer);
	/* And the http reply */
	http = format (0, http_response, vec_len (html), html);

	/* Send it */
	send_data (args, http);

	out:
	/* Cleanup */
	vec_free (request);
	vec_free (reply);
	vec_free (html);
	vec_free (http);

	free_http_process (args);
	return (0);
	}

	static void
	alloc_http_process (builtin_http_server_args * args)
	{
	char *name;
	vlib_node_t *n;
	http_server_main_t *hsm = &http_server_main;
	vlib_main_t *vm = hsm->vlib_main;
	uword l = vec_len (hsm->free_http_cli_process_node_indices);
	builtin_http_server_args **save_args;

	if (vec_len (hsm->free_http_cli_process_node_indices) > 0)
	{
	n = vlib_get_node (vm, hsm->free_http_cli_process_node_indices[l - 1]);
	vlib_node_set_state (vm, n->index, VLIB_NODE_STATE_POLLING);
	_vec_len (hsm->free_http_cli_process_node_indices) = l - 1;
	}
	else
	{
	static vlib_node_registration_t r = {
	.function = http_cli_process,
	.type = VLIB_NODE_TYPE_PROCESS,
	.process_log2_n_stack_bytes = 16,
	.runtime_data_bytes = sizeof (void *),
	};

	name = (char *) format (0, "http-cli-%d", l);
	r.name = name;
	vlib_register_node (vm, &r);
	vec_free (name);

	n = vlib_get_node (vm, r.index);
	}

	/* Save the node index in the args. It won't be zero. */
	args->node_index = n->index;

	/* Save the args (pointer) in the node runtime */
	save_args = vlib_node_get_runtime_data (vm, n->index);
	*save_args = args;

	vlib_start_process (vm, n->runtime_index);
	}

	static void
	alloc_http_process_callback (void *cb_args)
	{
	alloc_http_process ((builtin_http_server_args *) cb_args);
	}

	static int
	http_server_rx_callback (stream_session_t * s)
	{
	u32 max_dequeue;
	int actual_transfer;
	http_server_main_t *hsm = &http_server_main;
	svm_fifo_t *rx_fifo;
	builtin_http_server_args *args;

	rx_fifo = s->server_rx_fifo;
	max_dequeue = svm_fifo_max_dequeue (rx_fifo);
	svm_fifo_unset_event (rx_fifo);
	if (PREDICT_FALSE (max_dequeue == 0))
	return 0;

	vec_validate (hsm->rx_buf, max_dequeue - 1);
	_vec_len (hsm->rx_buf) = max_dequeue;

	actual_transfer = svm_fifo_dequeue_nowait (rx_fifo, max_dequeue,
	hsm->rx_buf);
	ASSERT (actual_transfer > 0);
	_vec_len (hsm->rx_buf) = actual_transfer;

	/* send the command to a new/recycled vlib process */
	args = clib_mem_alloc (sizeof (*args));
	args->data = vec_dup (hsm->rx_buf);
	args->session_handle = stream_session_handle (s);

	/* Send an RPC request via the thread-0 input node */
	if (vlib_get_thread_index () != 0)
	{
	session_fifo_event_t evt;
	evt.rpc_args.fp = alloc_http_process_callback;
	evt.rpc_args.arg = args;
	evt.event_type = FIFO_EVENT_RPC;
	unix_shared_memory_queue_add
	(session_manager_get_vpp_event_queue (0 /* main thread */ ),
	(u8 ) & evt, 0 / do wait for mutex */ );
	}
	else
	alloc_http_process (args);
	return 0;
	}

	static int
	builtin_session_accept_callback (stream_session_t * s)
	{
	http_server_main_t *bsm = &http_server_main;

	bsm->vpp_queue[s->thread_index] =
	session_manager_get_vpp_event_queue (s->thread_index);
	s->session_state = SESSION_STATE_READY;
	bsm->byte_index = 0;
	return 0;
	}

	static void
	builtin_session_disconnect_callback (stream_session_t * s)
	{
	http_server_main_t *bsm = &http_server_main;
	vnet_disconnect_args_t _a, *a = &_a;

	a->handle = stream_session_handle (s);
	a->app_index = bsm->app_index;
	vnet_disconnect_session (a);
	}

	static void
	builtin_session_reset_callback (stream_session_t * s)
	{
	clib_warning ("called.. ");

	stream_session_cleanup (s);
	}

	static int
	builtin_session_connected_callback (u32 app_index, u32 api_context,
	stream_session_t * s, u8 is_fail)
	{
	clib_warning ("called...");
	return -1;
	}

	static int
	builtin_add_segment_callback (u32 client_index,
	const u8 * seg_name, u32 seg_size)
	{
	clib_warning ("called...");
	return -1;
	}

	static int
	builtin_redirect_connect_callback (u32 client_index, void *mp)
	{
	clib_warning ("called...");
	return -1;
	}

	static session_cb_vft_t builtin_session_cb_vft = {
	.session_accept_callback = builtin_session_accept_callback,
	.session_disconnect_callback = builtin_session_disconnect_callback,
	.session_connected_callback = builtin_session_connected_callback,
	.add_segment_callback = builtin_add_segment_callback,
	.redirect_connect_callback = builtin_redirect_connect_callback,
	.builtin_server_rx_callback = http_server_rx_callback,
	.session_reset_callback = builtin_session_reset_callback
	};

	/* Abuse VPP's input queue */
	static int
	create_api_loopback (vlib_main_t * vm)
	{
	http_server_main_t *hsm = &http_server_main;
	api_main_t *am = &api_main;
	vl_shmem_hdr_t *shmem_hdr;

	shmem_hdr = am->shmem_hdr;
	hsm->vl_input_queue = shmem_hdr->vl_input_queue;
	hsm->my_client_index =
	vl_api_memclnt_create_internal ("tcp_test_client", hsm->vl_input_queue);
	return 0;
	}

	static int
	server_attach ()
	{
	http_server_main_t *hsm = &http_server_main;
	u8 segment_name[128];
	u64 options[SESSION_OPTIONS_N_OPTIONS];
	vnet_app_attach_args_t _a, *a = &_a;

	memset (a, 0, sizeof (*a));
	memset (options, 0, sizeof (options));

	a->api_client_index = hsm->my_client_index;
	a->session_cb_vft = &builtin_session_cb_vft;
	a->options = options;
	a->options[SESSION_OPTIONS_SEGMENT_SIZE] = 128 << 20;
	a->options[SESSION_OPTIONS_RX_FIFO_SIZE] = 8 << 10;
	a->options[SESSION_OPTIONS_TX_FIFO_SIZE] = 32 << 10;
	a->options[APP_OPTIONS_FLAGS] = APP_OPTIONS_FLAGS_BUILTIN_APP;
	a->options[APP_OPTIONS_PREALLOC_FIFO_PAIRS] = 16;
	a->segment_name = segment_name;
	a->segment_name_length = ARRAY_LEN (segment_name);

	if (vnet_application_attach (a))
	{
	clib_warning ("failed to attach server");
	return -1;
	}
	hsm->app_index = a->app_index;
	return 0;
	}

	static int
	server_listen ()
	{
	http_server_main_t *hsm = &http_server_main;
	vnet_bind_args_t _a, *a = &_a;
	memset (a, 0, sizeof (*a));
	a->app_index = hsm->app_index;
	a->uri = "tcp://0.0.0.0/80";
	return vnet_bind_uri (a);
	}

	static int
	server_create (vlib_main_t * vm)
	{
	http_server_main_t *hsm = &http_server_main;
	u32 num_threads;
	vlib_thread_main_t *vtm = vlib_get_thread_main ();

	ASSERT (hsm->my_client_index == (u32) ~ 0);
	if (create_api_loopback (vm))
	return -1;

	num_threads = 1 /* main thread */ + vtm->n_threads;
	vec_validate (http_server_main.vpp_queue, num_threads - 1);

	if (server_attach ())
	{
	clib_warning ("failed to attach server");
	return -1;
	}
	if (server_listen ())
	{
	clib_warning ("failed to start listening");
	return -1;
	}
	return 0;
	}

	static clib_error_t *
	server_create_command_fn (vlib_main_t * vm,
	unformat_input_t * input, vlib_cli_command_t * cmd)
	{
	http_server_main_t *hsm = &http_server_main;
	int rv;

	if (hsm->my_client_index != (u32) ~ 0)
	return clib_error_return (0, "test http server is already running");

	vnet_session_enable_disable (vm, 1 /* turn on TCP, etc. */ );
	rv = server_create (vm);
	switch (rv)
	{
	case 0:
	break;
	default:
	return clib_error_return (0, "server_create returned %d", rv);
	}
	return 0;
	}

	/* INDENT-OFF */
	VLIB_CLI_COMMAND (server_create_command, static) =
	{
	.path = "test http server",
	.short_help = "test http server",
	.function = server_create_command_fn,
	};
	/* INDENT-ON */

	static clib_error_t *
	builtin_http_server_main_init (vlib_main_t * vm)
	{
	http_server_main_t *hsm = &http_server_main;
	hsm->my_client_index = ~0;
	hsm->vlib_main = vm;

	return 0;
	}

	VLIB_INIT_FUNCTION (builtin_http_server_main_init);

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