api: configurable binary api client rx pthread fcn

Add vl_client_connect_to_vlib_thread_fn (...) and export the
memory_client_main_t definition.

If you use this new API, make sure not to miss the setjmp / longjmp
dance shown in .../src/vlibmemory/memory_client.c:rx_thread_fn(...),
which is required for the rx pthread to terminate cleanly; please
process client delete reply messages in the rx thread...

Type: refactor

Signed-off-by: Dave Barach <dave@barachs.net>
Change-Id: Ia67038ec59e2e14b174c67afca15b2c3f67a4d20
diff --git a/src/vlibmemory/memory_client.c b/src/vlibmemory/memory_client.c
index 25c01f1..c61c3cb 100644
--- a/src/vlibmemory/memory_client.c
+++ b/src/vlibmemory/memory_client.c
@@ -44,17 +44,6 @@
 #include <vlibmemory/vl_memory_api_h.h>
 #undef vl_printfun
 
-typedef struct
-{
-  u8 rx_thread_jmpbuf_valid;
-  u8 connected_to_vlib;
-  jmp_buf rx_thread_jmpbuf;
-  pthread_t rx_thread_handle;
-  /* Plugin message base lookup scheme */
-  volatile u8 first_msg_id_reply_ready;
-  u16 first_msg_id_reply;
-} memory_client_main_t;
-
 memory_client_main_t memory_client_main;
 
 static void *
@@ -390,7 +379,8 @@
 static int
 connect_to_vlib_internal (const char *svm_name,
 			  const char *client_name,
-			  int rx_queue_size, int want_pthread, int do_map)
+			  int rx_queue_size, void *(*thread_fn) (void *),
+			  int do_map)
 {
   int rv = 0;
   memory_client_main_t *mm = &memory_client_main;
@@ -411,10 +401,10 @@
 
   /* Start the rx queue thread */
 
-  if (want_pthread)
+  if (thread_fn)
     {
       rv = pthread_create (&mm->rx_thread_handle,
-			   NULL /*attr */ , rx_thread_fn, 0);
+			   NULL /*attr */ , thread_fn, 0);
       if (rv)
 	{
 	  clib_warning ("pthread_create returned %d", rv);
@@ -435,8 +425,7 @@
 			   const char *client_name, int rx_queue_size)
 {
   return connect_to_vlib_internal (svm_name, client_name, rx_queue_size,
-				   1 /* want pthread */ ,
-				   1 /* do map */ );
+				   rx_thread_fn, 1 /* do map */ );
 }
 
 int
@@ -445,7 +434,7 @@
 					 int rx_queue_size)
 {
   return connect_to_vlib_internal (svm_name, client_name, rx_queue_size,
-				   0 /* want pthread */ ,
+				   0 /* no rx_thread_fn */ ,
 				   1 /* do map */ );
 }
 
@@ -454,8 +443,7 @@
 				  const char *client_name, int rx_queue_size)
 {
   return connect_to_vlib_internal (svm_name, client_name, rx_queue_size,
-				   1 /* want pthread */ ,
-				   0 /* dont map */ );
+				   rx_thread_fn, 0 /* dont map */ );
 }
 
 int
@@ -468,6 +456,17 @@
 				   0 /* dont map */ );
 }
 
+int
+vl_client_connect_to_vlib_thread_fn (const char *svm_name,
+				     const char *client_name,
+				     int rx_queue_size,
+				     void *(*thread_fn) (void *))
+{
+  return connect_to_vlib_internal (svm_name, client_name, rx_queue_size,
+				   thread_fn, 1 /* do map */ );
+}
+
+
 static void
 disconnect_from_vlib_internal (u8 do_unmap)
 {