Bug#16293702 REMOVE DEAD CODE DEFINED WITH SIGNALS_DONT_BREAK_READ

Description: Removed code defined under SIGNALS_DONT_BREAK_READ 
compile time macro

Author: prabakaran thirumalai

sql/mysqld.cc

@@ -127,7 +127,7 @@ using std::vector;
 
 /* We have HAVE_purify below as this speeds up the shutdown of MySQL */
 
-#if defined(HAVE_DEC_3_2_THREADS) || defined(SIGNALS_DONT_BREAK_READ) || defined(HAVE_purify) && defined(__linux__)
+#if defined(HAVE_DEC_3_2_THREADS) || defined(HAVE_purify) && defined(__linux__)
 #define HAVE_CLOSE_SERVER_SOCK 1
 #endif
 
@@ -1512,11 +1512,6 @@ void kill_mysql(void)
 {
   DBUG_ENTER("kill_mysql");
 
-#if defined(SIGNALS_DONT_BREAK_READ) && !defined(EMBEDDED_LIBRARY)
-  abort_loop=1;         // Break connection loops
-  close_server_sock();        // Force accept to wake up
-#endif
-
 #if defined(__WIN__)
 #if !defined(EMBEDDED_LIBRARY)
   {
@@ -1537,22 +1532,11 @@ void kill_mysql(void)
   {
     DBUG_PRINT("error",("Got error %d from pthread_kill",errno)); /* purecov: inspected */
   }
-#elif !defined(SIGNALS_DONT_BREAK_READ)
+#else 
   kill(current_pid, MYSQL_KILL_SIGNAL);
 #endif
   DBUG_PRINT("quit",("After pthread_kill"));
   shutdown_in_progress=1;     // Safety if kill didn't work
-#ifdef SIGNALS_DONT_BREAK_READ
-  if (!kill_in_progress)
-  {
-    pthread_t tmp;
-    abort_loop=1;
-    if (mysql_thread_create(0, /* Not instrumented */
-                            &tmp, &connection_attrib, kill_server_thread,
-                            (void*) 0))
-      sql_print_error("Can't create thread to kill server");
-  }
-#endif
   DBUG_VOID_RETURN;
 }
 
@@ -1676,22 +1660,14 @@ static void clean_up_error_log_mutex()
 /**
   cleanup all memory and end program nicely.
 
-    If SIGNALS_DONT_BREAK_READ is defined, this function is called
-    by the main thread. To get MySQL to shut down nicely in this case
-    (Mac OS X) we have to call exit() instead if pthread_exit().
-
   @note
     This function never returns.
 */
 void unireg_end(void)
 {
   clean_up(1);
   my_thread_end();
-#if defined(SIGNALS_DONT_BREAK_READ)
-  exit(0);
-#else
   pthread_exit(0);        // Exit is in main thread
-#endif
 }
 
 
@@ -6096,24 +6072,6 @@ static void create_new_thread(THD *thd)
 }
 #endif /* EMBEDDED_LIBRARY */
 
-
-#ifdef SIGNALS_DONT_BREAK_READ
-inline void kill_broken_server()
-{
-  /* hack to get around signals ignored in syscalls for problem OS's */
-  if (mysql_get_fd(unix_sock) == INVALID_SOCKET ||
-      (!opt_disable_networking && mysql_socket_getfd(ip_sock) == INVALID_SOCKET))
-  {
-    select_thread_in_use = 0;
-    /* The following call will never return */
-    kill_server((void*) MYSQL_KILL_SIGNAL);
-  }
-}
-#define MAYBE_BROKEN_SYSCALL kill_broken_server();
-#else
-#define MAYBE_BROKEN_SYSCALL
-#endif
-
   /* Handle new connections and spawn new process to handle them */
 
 #ifndef EMBEDDED_LIBRARY
@@ -6176,7 +6134,6 @@ void handle_connections_sockets()
 #endif
 
   DBUG_PRINT("general",("Waiting for connections."));
-  MAYBE_BROKEN_SYSCALL;
   while (!abort_loop)
   {
 #ifdef HAVE_POLL
@@ -6200,13 +6157,11 @@ void handle_connections_sockets()
         if (!select_errors++ && !abort_loop)  /* purecov: inspected */
           sql_print_error("mysqld: Got error %d from select",socket_errno); /* purecov: inspected */
       }
-      MAYBE_BROKEN_SYSCALL
       continue;
     }
 
     if (abort_loop)
     {
-      MAYBE_BROKEN_SYSCALL;
       break;
     }
 
@@ -6258,7 +6213,6 @@ void handle_connections_sockets()
       if (mysql_socket_getfd(new_sock) != INVALID_SOCKET ||
           (socket_errno != SOCKET_EINTR && socket_errno != SOCKET_EAGAIN))
         break;
-      MAYBE_BROKEN_SYSCALL;
 #if !defined(NO_FCNTL_NONBLOCK)
       if (!(test_flags & TEST_BLOCKING))
       {
@@ -6281,7 +6235,6 @@ void handle_connections_sockets()
       statistic_increment_rwlock(connection_errors_accept, &LOCK_status);
       if ((error_count++ & 255) == 0)   // This can happen often
         sql_perror("Error in accept");
-      MAYBE_BROKEN_SYSCALL;
       if (socket_errno == SOCKET_ENFILE || socket_errno == SOCKET_EMFILE)
         sleep(1);       // Give other threads some time
       continue;