api: refactor vlibmemory

- separate client/server code for both memory and socket apis
- separate memory api code from generic vlib api code
- move unix_shared_memory_fifo to svm and rename to svm_fifo_t
- overall declutter

Change-Id: I90cdd98ff74d0787d58825b914b0f1eafcfa4dc2
Signed-off-by: Florin Coras <fcoras@cisco.com>

1 files changed, 804 insertions, 0 deletions

diff --git a/src/vlibmemory/socket_api.c b/src/vlibmemory/socket_api.c
new file mode 100644
index 00000000000..3d505359d3b
--- /dev/null
+++ b/src/vlibmemory/socket_api.c
@@ -0,0 +1,804 @@
+/*
+ *------------------------------------------------------------------
+ * socksvr_vlib.c
+ *
+ * Copyright (c) 2009 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 <sys/types.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <sys/ioctl.h>
+#include <fcntl.h>
+#include <sys/stat.h>
+
+#include <vppinfra/byte_order.h>
+#include <svm/memfd.h>
+#include <vlibmemory/api.h>
+
+#include <vlibmemory/vl_memory_msg_enum.h>
+
+#define vl_typedefs		/* define message structures */
+#include <vlibmemory/vl_memory_api_h.h>
+#undef vl_typedefs
+
+/* instantiate all the print functions we know about */
+#define vl_print(handle, ...) vlib_cli_output (handle, __VA_ARGS__)
+#define vl_printfun
+#include <vlibmemory/vl_memory_api_h.h>
+#undef vl_printfun
+
+/* instantiate all the endian swap functions we know about */
+#define vl_endianfun
+#include <vlibmemory/vl_memory_api_h.h>
+#undef vl_endianfun
+
+socket_main_t socket_main;
+
+void
+vl_sock_api_dump_clients (vlib_main_t * vm, api_main_t * am)
+{
+  vl_api_registration_t *reg;
+  socket_main_t *sm = &socket_main;
+  clib_file_main_t *fm = &file_main;
+  clib_file_t *f;
+
+  /*
+   * Must have at least one active client, not counting the
+   * REGISTRATION_TYPE_SOCKET_LISTEN bind/accept socket
+   */
+  if (pool_elts (sm->registration_pool) < 2)
+    return;
+
+  vlib_cli_output (vm, "Socket clients");
+  vlib_cli_output (vm, "%20s %8s", "Name", "Fildesc");
+    /* *INDENT-OFF* */
+    pool_foreach (reg, sm->registration_pool,
+    ({
+        if (reg->registration_type == REGISTRATION_TYPE_SOCKET_SERVER) {
+            f = pool_elt_at_index (fm->file_pool, reg->clib_file_index);
+            vlib_cli_output (vm, "%20s %8d",
+                             reg->name, f->file_descriptor);
+        }
+    }));
+/* *INDENT-ON* */
+}
+
+void
+vl_socket_api_send (vl_api_registration_t * rp, u8 * elem)
+{
+#if CLIB_DEBUG > 1
+  u32 output_length;
+#endif
+  socket_main_t *sm = &socket_main;
+  u16 msg_id = ntohs (*(u16 *) elem);
+  api_main_t *am = &api_main;
+  msgbuf_t *mb = (msgbuf_t *) (elem - offsetof (msgbuf_t, data));
+  clib_file_t *cf = clib_file_get (&file_main, rp->clib_file_index);
+  vl_api_registration_t *sock_rp;
+
+  ASSERT (rp->registration_type > REGISTRATION_TYPE_SHMEM);
+
+  if (msg_id >= vec_len (am->api_trace_cfg))
+    {
+      clib_warning ("id out of range: %d", msg_id);
+      vl_msg_api_free ((void *) elem);
+      return;
+    }
+
+  sock_rp = pool_elt_at_index (sm->registration_pool,
+			       rp->vl_api_registration_pool_index);
+  ASSERT (sock_rp);
+
+  /* Add the msgbuf_t to the output vector */
+  vl_socket_add_pending_output_no_flush (cf, sock_rp, (u8 *) mb,
+					 sizeof (*mb));
+  /* Send the message */
+  vl_socket_add_pending_output (cf, sock_rp, elem, ntohl (mb->data_len));
+
+#if CLIB_DEBUG > 1
+  output_length = sizeof (*mb) + ntohl (mb->data_len);
+  clib_warning ("wrote %u bytes to fd %d", output_length,
+		cf->file_descriptor);
+#endif
+
+  vl_msg_api_free ((void *) elem);
+}
+
+void
+vl_socket_free_registration_index (u32 pool_index)
+{
+  int i;
+  vl_api_registration_t *rp;
+  if (pool_is_free_index (socket_main.registration_pool, pool_index))
+    {
+      clib_warning ("main pool index %d already free", pool_index);
+      return;
+    }
+  rp = pool_elt_at_index (socket_main.registration_pool, pool_index);
+
+  ASSERT (rp->registration_type != REGISTRATION_TYPE_FREE);
+  for (i = 0; i < vec_len (rp->additional_fds_to_close); i++)
+    if (close (rp->additional_fds_to_close[i]) < 0)
+      clib_unix_warning ("close");
+  vec_free (rp->additional_fds_to_close);
+  vec_free (rp->name);
+  vec_free (rp->unprocessed_input);
+  vec_free (rp->output_vector);
+  rp->registration_type = REGISTRATION_TYPE_FREE;
+  pool_put (socket_main.registration_pool, rp);
+}
+
+void
+vl_socket_process_api_msg (clib_file_t * uf, vl_api_registration_t * rp,
+			   i8 * input_v)
+{
+  msgbuf_t *mbp = (msgbuf_t *) input_v;
+
+  u8 *the_msg = (u8 *) (mbp->data);
+  socket_main.current_uf = uf;
+  socket_main.current_rp = rp;
+  vl_msg_api_socket_handler (the_msg);
+  socket_main.current_uf = 0;
+  socket_main.current_rp = 0;
+}
+
+clib_error_t *
+vl_socket_read_ready (clib_file_t * uf)
+{
+  clib_file_main_t *fm = &file_main;
+  vlib_main_t *vm = vlib_get_main ();
+  vl_api_registration_t *rp;
+  int n;
+  i8 *msg_buffer = 0;
+  u8 *data_for_process;
+  u32 msg_len;
+  u32 save_input_buffer_length = vec_len (socket_main.input_buffer);
+  vl_socket_args_for_process_t *a;
+  msgbuf_t *mbp;
+  int mbp_set = 0;
+
+  rp = pool_elt_at_index (socket_main.registration_pool, uf->private_data);
+
+  n = read (uf->file_descriptor, socket_main.input_buffer,
+	    vec_len (socket_main.input_buffer));
+
+  if (n <= 0 && errno != EAGAIN)
+    {
+      clib_file_del (fm, uf);
+
+      if (!pool_is_free (socket_main.registration_pool, rp))
+	{
+	  u32 index = rp - socket_main.registration_pool;
+	  vl_socket_free_registration_index (index);
+	}
+      else
+	{
+	  clib_warning ("client index %d already free?",
+			rp->vl_api_registration_pool_index);
+	}
+      return 0;
+    }
+
+  _vec_len (socket_main.input_buffer) = n;
+
+  /*
+   * Look for bugs here. This code is tricky because
+   * data read from a stream socket does not honor message
+   * boundaries. In the case of a long message (>4K bytes)
+   * we have to do (at least) 2 reads, etc.
+   */
+  do
+    {
+      if (vec_len (rp->unprocessed_input))
+	{
+	  vec_append (rp->unprocessed_input, socket_main.input_buffer);
+	  msg_buffer = rp->unprocessed_input;
+	}
+      else
+	{
+	  msg_buffer = socket_main.input_buffer;
+	  mbp_set = 0;
+	}
+
+      if (mbp_set == 0)
+	{
+	  /* Any chance that we have a complete message? */
+	  if (vec_len (msg_buffer) <= sizeof (msgbuf_t))
+	    goto save_and_split;
+
+	  mbp = (msgbuf_t *) msg_buffer;
+	  msg_len = ntohl (mbp->data_len);
+	  mbp_set = 1;
+	}
+
+      /* We don't have the entire message yet. */
+      if (mbp_set == 0
+	  || (msg_len + sizeof (msgbuf_t)) > vec_len (msg_buffer))
+	{
+	save_and_split:
+	  /* if we were using the input buffer save the fragment */
+	  if (msg_buffer == socket_main.input_buffer)
+	    {
+	      ASSERT (vec_len (rp->unprocessed_input) == 0);
+	      vec_validate (rp->unprocessed_input, vec_len (msg_buffer) - 1);
+	      clib_memcpy (rp->unprocessed_input, msg_buffer,
+			   vec_len (msg_buffer));
+	      _vec_len (rp->unprocessed_input) = vec_len (msg_buffer);
+	    }
+	  _vec_len (socket_main.input_buffer) = save_input_buffer_length;
+	  return 0;
+	}
+
+      data_for_process = (u8 *) vec_dup (msg_buffer);
+      _vec_len (data_for_process) = (msg_len + sizeof (msgbuf_t));
+      pool_get (socket_main.process_args, a);
+      a->clib_file = uf;
+      a->regp = rp;
+      a->data = data_for_process;
+
+      vlib_process_signal_event (vm, vl_api_clnt_node.index,
+				 SOCKET_READ_EVENT,
+				 a - socket_main.process_args);
+      if (n > (msg_len + sizeof (*mbp)))
+	vec_delete (msg_buffer, msg_len + sizeof (*mbp), 0);
+      else
+	_vec_len (msg_buffer) = 0;
+      n -= msg_len + sizeof (msgbuf_t);
+      msg_len = 0;
+      mbp_set = 0;
+    }
+  while (n > 0);
+
+  _vec_len (socket_main.input_buffer) = save_input_buffer_length;
+
+  return 0;
+}
+
+void
+vl_socket_add_pending_output (clib_file_t * uf,
+			      vl_api_registration_t * rp,
+			      u8 * buffer, uword buffer_bytes)
+{
+  clib_file_main_t *fm = &file_main;
+
+  vec_add (rp->output_vector, buffer, buffer_bytes);
+  if (vec_len (rp->output_vector) > 0)
+    {
+      int skip_update = 0 != (uf->flags & UNIX_FILE_DATA_AVAILABLE_TO_WRITE);
+      uf->flags |= UNIX_FILE_DATA_AVAILABLE_TO_WRITE;
+      if (!skip_update)
+	fm->file_update (uf, UNIX_FILE_UPDATE_MODIFY);
+    }
+}
+
+void
+vl_socket_add_pending_output_no_flush (clib_file_t * uf,
+				       vl_api_registration_t * rp,
+				       u8 * buffer, uword buffer_bytes)
+{
+  vec_add (rp->output_vector, buffer, buffer_bytes);
+}
+
+static void
+socket_del_pending_output (clib_file_t * uf,
+			   vl_api_registration_t * rp, uword n_bytes)
+{
+  clib_file_main_t *fm = &file_main;
+
+  vec_delete (rp->output_vector, n_bytes, 0);
+  if (vec_len (rp->output_vector) <= 0)
+    {
+      int skip_update = 0 == (uf->flags & UNIX_FILE_DATA_AVAILABLE_TO_WRITE);
+      uf->flags &= ~UNIX_FILE_DATA_AVAILABLE_TO_WRITE;
+      if (!skip_update)
+	fm->file_update (uf, UNIX_FILE_UPDATE_MODIFY);
+    }
+}
+
+clib_error_t *
+vl_socket_write_ready (clib_file_t * uf)
+{
+  clib_file_main_t *fm = &file_main;
+  vl_api_registration_t *rp;
+  int n;
+
+  rp = pool_elt_at_index (socket_main.registration_pool, uf->private_data);
+
+  /* Flush output vector. */
+  n = write (uf->file_descriptor,
+	     rp->output_vector, vec_len (rp->output_vector));
+  if (n < 0)
+    {
+#if DEBUG > 2
+      clib_warning ("write error, close the file...\n");
+#endif
+      clib_file_del (fm, uf);
+
+      vl_socket_free_registration_index (rp - socket_main.registration_pool);
+      return 0;
+    }
+
+  else if (n > 0)
+    socket_del_pending_output (uf, rp, n);
+
+  return 0;
+}
+
+clib_error_t *
+vl_socket_error_ready (clib_file_t * uf)
+{
+  vl_api_registration_t *rp;
+  clib_file_main_t *fm = &file_main;
+
+  rp = pool_elt_at_index (socket_main.registration_pool, uf->private_data);
+  clib_file_del (fm, uf);
+  vl_socket_free_registration_index (rp - socket_main.registration_pool);
+
+  return 0;
+}
+
+void
+socksvr_file_add (clib_file_main_t * fm, int fd)
+{
+  vl_api_registration_t *rp;
+  clib_file_t template = { 0 };
+
+  pool_get (socket_main.registration_pool, rp);
+  memset (rp, 0, sizeof (*rp));
+
+  template.read_function = vl_socket_read_ready;
+  template.write_function = vl_socket_write_ready;
+  template.error_function = vl_socket_error_ready;
+  template.file_descriptor = fd;
+  template.private_data = rp - socket_main.registration_pool;
+
+  rp->registration_type = REGISTRATION_TYPE_SOCKET_SERVER;
+  rp->vl_api_registration_pool_index = rp - socket_main.registration_pool;
+  rp->clib_file_index = clib_file_add (fm, &template);
+}
+
+static clib_error_t *
+socksvr_accept_ready (clib_file_t * uf)
+{
+  clib_file_main_t *fm = &file_main;
+  socket_main_t *sm = &socket_main;
+  clib_socket_t *sock = &sm->socksvr_listen_socket;
+  clib_socket_t client;
+  clib_error_t *error;
+
+  error = clib_socket_accept (sock, &client);
+
+  if (error)
+    return error;
+
+  socksvr_file_add (fm, client.fd);
+  return 0;
+}
+
+static clib_error_t *
+socksvr_bogus_write (clib_file_t * uf)
+{
+  clib_warning ("why am I here?");
+  return 0;
+}
+
+/*
+ * vl_api_sockclnt_create_t_handler
+ */
+void
+vl_api_sockclnt_create_t_handler (vl_api_sockclnt_create_t * mp)
+{
+  vl_api_registration_t *regp;
+  vl_api_sockclnt_create_reply_t *rp;
+  int rv = 0;
+
+  regp = socket_main.current_rp;
+
+  ASSERT (regp->registration_type == REGISTRATION_TYPE_SOCKET_SERVER);
+
+  regp->name = format (0, "%s%c", mp->name, 0);
+
+  rp = vl_msg_api_alloc (sizeof (*rp));
+  rp->_vl_msg_id = htons (VL_API_SOCKCLNT_CREATE_REPLY);
+  rp->handle = (uword) regp;
+  rp->index = (uword) regp->vl_api_registration_pool_index;
+  rp->context = mp->context;
+  rp->response = htonl (rv);
+
+  vl_api_send_msg (regp, (u8 *) rp);
+}
+
+/*
+ * vl_api_sockclnt_delete_t_handler
+ */
+void
+vl_api_sockclnt_delete_t_handler (vl_api_sockclnt_delete_t * mp)
+{
+  vl_api_registration_t *regp;
+  vl_api_sockclnt_delete_reply_t *rp;
+
+  if (!pool_is_free_index (socket_main.registration_pool, mp->index))
+    {
+      regp = pool_elt_at_index (socket_main.registration_pool, mp->index);
+
+      rp = vl_msg_api_alloc (sizeof (*rp));
+      rp->_vl_msg_id = htons (VL_API_SOCKCLNT_DELETE_REPLY);
+      rp->handle = mp->handle;
+      rp->response = htonl (1);
+
+      vl_api_send_msg (regp, (u8 *) rp);
+
+      clib_file_del (&file_main, file_main.file_pool + regp->clib_file_index);
+
+      vl_socket_free_registration_index (mp->index);
+    }
+  else
+    {
+      clib_warning ("unknown client ID %d", mp->index);
+    }
+}
+
+static clib_error_t *
+send_fd_msg (int socket_fd, int fd_to_share)
+{
+  struct msghdr mh = { 0 };
+  struct iovec iov[1];
+  char ctl[CMSG_SPACE (sizeof (int))];
+  char *msg = "memfd";
+  int rv;
+
+  iov[0].iov_base = msg;
+  iov[0].iov_len = strlen (msg);
+  mh.msg_iov = iov;
+  mh.msg_iovlen = 1;
+
+  struct cmsghdr *cmsg;
+  memset (&ctl, 0, sizeof (ctl));
+  mh.msg_control = ctl;
+  mh.msg_controllen = sizeof (ctl);
+  cmsg = CMSG_FIRSTHDR (&mh);
+  cmsg->cmsg_len = CMSG_LEN (sizeof (int));
+  cmsg->cmsg_level = SOL_SOCKET;
+  cmsg->cmsg_type = SCM_RIGHTS;
+  memcpy (CMSG_DATA (cmsg), &fd_to_share, sizeof (int));
+
+  rv = sendmsg (socket_fd, &mh, 0);
+  if (rv < 0)
+    return clib_error_return_unix (0, "sendmsg");
+  return 0;
+}
+
+vl_api_shm_elem_config_t *
+vl_api_make_shm_config (vl_api_sock_init_shm_t * mp)
+{
+  vl_api_shm_elem_config_t *config = 0, *c;
+  u64 cfg;
+  int i;
+
+  if (!mp->nitems)
+    {
+      vec_validate (config, 3);
+      config[0].type = VL_API_VLIB_RING;
+      config[0].count = 128;
+      config[0].size = 256;
+      config[1].type = VL_API_CLIENT_RING;
+      config[1].count = 128;
+      config[1].size = 1024;
+      config[2].type = VL_API_CLIENT_RING;
+      config[2].count = 8;
+      config[2].size = 4096;
+      config[3].type = VL_API_QUEUE;
+      config[3].count = 128;
+      config[3].size = sizeof (uword);
+    }
+  else
+    {
+      vec_validate (config, mp->nitems - 1);
+      for (i = 0; i < mp->nitems; i++)
+	{
+	  cfg = mp->configs[i];
+	  /* Pretty much a hack but it avoids defining our own api type
+	   * in memclnt.api */
+	  c = (vl_api_shm_elem_config_t *) & cfg;
+	  config[i].type = c->type;
+	  config[i].count = c->count;
+	  config[i].size = c->size;
+	}
+    }
+  return config;
+}
+
+/*
+ * Bootstrap shm api using the socket api
+ */
+void
+vl_api_sock_init_shm_t_handler (vl_api_sock_init_shm_t * mp)
+{
+  vl_api_sock_init_shm_reply_t *rmp;
+  memfd_private_t _memfd_private, *memfd = &_memfd_private;
+  svm_map_region_args_t _args, *a = &_args;
+  vl_api_registration_t *regp;
+  api_main_t *am = &api_main;
+  svm_region_t *vlib_rp;
+  clib_file_t *cf;
+  vl_api_shm_elem_config_t *config = 0;
+  int rv;
+
+  regp = vl_api_client_index_to_registration (mp->client_index);
+  if (regp == 0)
+    {
+      clib_warning ("API client disconnected");
+      return;
+    }
+  if (regp->registration_type != REGISTRATION_TYPE_SOCKET_SERVER)
+    {
+      rv = -31;			/* VNET_API_ERROR_INVALID_REGISTRATION */
+      goto reply;
+    }
+
+  /*
+   * Set up a memfd segment of the requested size wherein the
+   * shmem data structures will be initialized
+   */
+  memset (memfd, 0, sizeof (*memfd));
+  memfd->memfd_size = mp->requested_size;
+  memfd->requested_va = 0ULL;
+  memfd->i_am_master = 1;
+  memfd->name = format (0, "%s%c", regp->name, 0);
+
+  if ((rv = memfd_master_init (memfd, mp->client_index)))
+    goto reply;
+
+  /* Remember to close this fd when the socket connection goes away */
+  vec_add1 (regp->additional_fds_to_close, memfd->fd);
+
+  /*
+   * Create a plausible svm_region in the memfd backed segment
+   */
+  memset (a, 0, sizeof (*a));
+  a->baseva = memfd->sh->memfd_va + MMAP_PAGESIZE;
+  a->size = memfd->memfd_size - MMAP_PAGESIZE;
+  /* $$$$ might want a different config parameter */
+  a->pvt_heap_size = am->api_pvt_heap_size;
+  a->flags = SVM_FLAGS_MHEAP;
+  svm_region_init_mapped_region (a, (svm_region_t *) a->baseva);
+
+  /*
+   * Part deux, initialize the svm_region_t shared-memory header
+   * api allocation rings, and so on.
+   */
+  config = vl_api_make_shm_config (mp);
+  vlib_rp = (svm_region_t *) a->baseva;
+  vl_init_shmem (vlib_rp, config, 1 /* is_vlib (dont-care) */ ,
+		 1 /* is_private */ );
+  vec_add1 (am->vlib_private_rps, vlib_rp);
+  memfd->sh->ready = 1;
+  vec_free (config);
+
+  /* Recompute the set of input queues to poll in memclnt_process */
+  vec_reset_length (vl_api_queue_cursizes);
+
+reply:
+
+  rmp = vl_msg_api_alloc (sizeof (*rmp));
+  rmp->_vl_msg_id = htons (VL_API_SOCK_INIT_SHM_REPLY);
+  rmp->context = mp->context;
+  rmp->retval = htonl (rv);
+
+  vl_api_send_msg (regp, (u8 *) rmp);
+
+  if (rv != 0)
+    return;
+
+  /*
+   * We need the reply message to make it out the back door
+   * before we send the magic fd message so force a flush
+   */
+  cf = clib_file_get (&file_main, regp->clib_file_index);
+  cf->write_function (cf);
+
+  /* Send the magic "here's your sign (aka fd)" socket message */
+  send_fd_msg (cf->file_descriptor, memfd->fd);
+}
+
+/*
+ * Create a memory-fd segment.
+ */
+void
+vl_api_memfd_segment_create_t_handler (vl_api_memfd_segment_create_t * mp)
+{
+  vl_api_memfd_segment_create_reply_t *rmp;
+  clib_file_t *cf;
+  memfd_private_t _memfd_private, *memfd = &_memfd_private;
+  vl_api_registration_t *regp;
+  int rv;
+
+  regp = vl_api_client_index_to_registration (mp->client_index);
+  if (regp == 0)
+    {
+      clib_warning ("API client disconnected");
+      return;
+    }
+
+  memset (memfd, 0, sizeof (*memfd));
+  memfd->memfd_size = mp->requested_size;
+  memfd->requested_va = 0ULL;
+  memfd->i_am_master = 1;
+  memfd->name = format (0, "%s%c", regp->name, 0);
+
+  /* Set up a memfd segment of the requested size */
+  if ((rv = memfd_master_init (memfd, mp->client_index)))
+    goto reply;
+
+  /* Remember to close this fd when the socket connection goes away */
+  vec_add1 (regp->additional_fds_to_close, memfd->fd);
+
+reply:
+
+  rmp = vl_msg_api_alloc (sizeof (*rmp));
+  rmp->_vl_msg_id = htons (VL_API_MEMFD_SEGMENT_CREATE_REPLY);
+  rmp->context = mp->context;
+  rmp->retval = htonl (rv);
+
+  vl_api_send_msg (regp, (u8 *) rmp);
+
+  if (rv != 0)
+    return;
+
+  /*
+   * We need the reply message to make it out the back door
+   * before we send the magic fd message.
+   */
+  cf = file_main.file_pool + regp->clib_file_index;
+  cf->write_function (cf);
+
+  /* send the magic "here's your sign (aka fd)" socket message */
+  send_fd_msg (cf->file_descriptor, memfd->fd);
+}
+
+#define foreach_vlib_api_msg                    	\
+_(SOCKCLNT_CREATE, sockclnt_create)             	\
+_(SOCKCLNT_DELETE, sockclnt_delete)			\
+_(SOCK_INIT_SHM, sock_init_shm) 			\
+_(MEMFD_SEGMENT_CREATE, memfd_segment_create)
+
+clib_error_t *
+vl_sock_api_init (vlib_main_t * vm)
+{
+  clib_file_main_t *fm = &file_main;
+  clib_file_t template = { 0 };
+  vl_api_registration_t *rp;
+  socket_main_t *sm = &socket_main;
+  clib_socket_t *sock = &sm->socksvr_listen_socket;
+  clib_error_t *error;
+
+  /* If not explicitly configured, do not bind/enable, etc. */
+  if (sm->socket_name == 0)
+    return 0;
+
+#define _(N,n)                                                  \
+    vl_msg_api_set_handlers(VL_API_##N, #n,                     \
+                           vl_api_##n##_t_handler,              \
+                           vl_noop_handler,                     \
+                           vl_api_##n##_t_endian,               \
+                           vl_api_##n##_t_print,                \
+                           sizeof(vl_api_##n##_t), 1);
+  foreach_vlib_api_msg;
+#undef _
+
+  vec_resize (sm->input_buffer, 4096);
+
+  sock->config = (char *) sm->socket_name;
+
+  /* mkdir of file socket, only under /run  */
+  if (strncmp (sock->config, "/run", 4) == 0)
+    {
+      u8 *tmp = format (0, "%s", sock->config);
+      int i = vec_len (tmp);
+      while (i && tmp[--i] != '/')
+	;
+
+      tmp[i] = 0;
+
+      if (i)
+	vlib_unix_recursive_mkdir ((char *) tmp);
+      vec_free (tmp);
+    }
+
+  sock->flags = CLIB_SOCKET_F_IS_SERVER | CLIB_SOCKET_F_SEQPACKET |
+    CLIB_SOCKET_F_ALLOW_GROUP_WRITE;
+  error = clib_socket_init (sock);
+  if (error)
+    return error;
+
+  pool_get (sm->registration_pool, rp);
+  memset (rp, 0, sizeof (*rp));
+
+  rp->registration_type = REGISTRATION_TYPE_SOCKET_LISTEN;
+
+  template.read_function = socksvr_accept_ready;
+  template.write_function = socksvr_bogus_write;
+  template.file_descriptor = sock->fd;
+  template.private_data = rp - sm->registration_pool;
+
+  rp->clib_file_index = clib_file_add (fm, &template);
+  return 0;
+}
+
+static clib_error_t *
+socket_exit (vlib_main_t * vm)
+{
+  clib_file_main_t *fm = &file_main;
+  socket_main_t *sm = &socket_main;
+  vl_api_registration_t *rp;
+
+  /* Defensive driving in case something wipes out early */
+  if (sm->registration_pool)
+    {
+      u32 index;
+        /* *INDENT-OFF* */
+        pool_foreach (rp, sm->registration_pool, ({
+            clib_file_del (fm, fm->file_pool + rp->clib_file_index);
+            index = rp->vl_api_registration_pool_index;
+            vl_socket_free_registration_index (index);
+        }));
+/* *INDENT-ON* */
+    }
+
+  return 0;
+}
+
+VLIB_MAIN_LOOP_EXIT_FUNCTION (socket_exit);
+
+static clib_error_t *
+socksvr_config (vlib_main_t * vm, unformat_input_t * input)
+{
+  socket_main_t *sm = &socket_main;
+
+  while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
+    {
+      if (unformat (input, "socket-name %s", &sm->socket_name))
+	;
+      else if (unformat (input, "default"))
+	{
+	  sm->socket_name = format (0, "%s%c", API_SOCKET_FILE, 0);
+	}
+      else
+	{
+	  return clib_error_return (0, "unknown input '%U'",
+				    format_unformat_error, input);
+	}
+    }
+  return 0;
+}
+
+VLIB_CONFIG_FUNCTION (socksvr_config, "socksvr");
+
+clib_error_t *
+vlibsocket_init (vlib_main_t * vm)
+{
+  return 0;
+}
+
+VLIB_INIT_FUNCTION (vlibsocket_init);
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */