MDEV-15359 Thread stay in "cleaning up" status after finishing

make thd_get_error_context_description() to show not just
thd->proc_info, but exactly the same thread state that SHOW PROCESSLIST
shows.

mysql-test/suite/plugins/r/processlist.result

+create table t1 (a int) engine=innodb;
+start transaction;
+insert t1 values (1);
+state from show engine innodb status
+ 
+state from show processlist
+
+drop table t1;

mysql-test/suite/plugins/t/processlist.test

+#
+# MDEV-15359 Thread stay in "cleaning up" status after finishing
+#
+source include/have_innodb.inc;
+
+create table t1 (a int) engine=innodb;
+start transaction;
+insert t1 values (1);
+let id=`select connection_id()`;
+connect con2,localhost,root;
+let s=query_get_value(show engine innodb status,Status,1);
+disable_query_log;
+eval select regexp_replace("$s", '(?s)^.*MySQL thread id $id,.*root([^\n]*)\n.*', '\\\\1') as `state from show engine innodb status`;
+eval select state as `state from show processlist` from information_schema.processlist where id = $id;
+enable_query_log;
+disconnect con2;
+connection default;
+drop table t1;

sql/sql_class.cc

@@ -717,103 +717,6 @@ extern "C"
 }
 
 
-/**
-  Dumps a text description of a thread, its security context
-  (user, host) and the current query.
-
-  @param thd thread context
-  @param buffer pointer to preferred result buffer
-  @param length length of buffer
-  @param max_query_len how many chars of query to copy (0 for all)
- 
-  @return Pointer to string
-*/
-
-extern "C"
-char *thd_get_error_context_description(THD *thd, char *buffer,
-                                        unsigned int length,
-                                        unsigned int max_query_len)
-{
-  String str(buffer, length, &my_charset_latin1);
-  const Security_context *sctx= &thd->main_security_ctx;
-  char header[256];
-  int len;
-
-  mysql_mutex_lock(&LOCK_thread_count);
-
-  /*
-    The pointers thd->query and thd->proc_info might change since they are
-    being modified concurrently. This is acceptable for proc_info since its
-    values doesn't have to very accurate and the memory it points to is static,
-    but we need to attempt a snapshot on the pointer values to avoid using NULL
-    values. The pointer to thd->query however, doesn't point to static memory
-    and has to be protected by thd->LOCK_thd_data or risk pointing to
-    uninitialized memory.
-  */
-  const char *proc_info= thd->proc_info;
-
-  len= my_snprintf(header, sizeof(header),
-                   "MySQL thread id %lu, OS thread handle 0x%lx, query id %lu",
-                   thd->thread_id, (ulong) thd->real_id, (ulong) thd->query_id);
-  str.length(0);
-  str.append(header, len);
-
-  if (sctx->host)
-  {
-    str.append(' ');
-    str.append(sctx->host);
-  }
-
-  if (sctx->ip)
-  {
-    str.append(' ');
-    str.append(sctx->ip);
-  }
-
-  if (sctx->user)
-  {
-    str.append(' ');
-    str.append(sctx->user);
-  }
-
-  if (proc_info)
-  {
-    str.append(' ');
-    str.append(proc_info);
-  }
-
-  /* Don't wait if LOCK_thd_data is used as this could cause a deadlock */
-  if (!mysql_mutex_trylock(&thd->LOCK_thd_data))
-  {
-    if (thd->query())
-    {
-      if (max_query_len < 1)
-        len= thd->query_length();
-      else
-        len= MY_MIN(thd->query_length(), max_query_len);
-      str.append('\n');
-      str.append(thd->query(), len);
-    }
-    mysql_mutex_unlock(&thd->LOCK_thd_data);
-  }
-  mysql_mutex_unlock(&LOCK_thread_count);
-
-  if (str.c_ptr_safe() == buffer)
-    return buffer;
-
-  /*
-    We have to copy the new string to the destination buffer because the string
-    was reallocated to a larger buffer to be able to fit.
-  */
-  DBUG_ASSERT(buffer != NULL);
-  length= MY_MIN(str.length(), length-1);
-  memcpy(buffer, str.c_ptr_quick(), length);
-  /* Make sure that the new string is null terminated */
-  buffer[length]= '\0';
-  return buffer;
-}
-
-
 #if MARIA_PLUGIN_INTERFACE_VERSION < 0x0200
 /**
   TODO: This function is for API compatibility, remove it eventually.

sql/sql_show.cc

@@ -9773,3 +9773,88 @@ static void get_cs_converted_string_value(THD *thd,
   return;
 }
 #endif
+
+/**
+  Dumps a text description of a thread, its security context
+  (user, host) and the current query.
+
+  @param thd thread context
+  @param buffer pointer to preferred result buffer
+  @param length length of buffer
+  @param max_query_len how many chars of query to copy (0 for all)
+
+  @return Pointer to string
+*/
+
+extern "C"
+char *thd_get_error_context_description(THD *thd, char *buffer,
+                                        unsigned int length,
+                                        unsigned int max_query_len)
+{
+  String str(buffer, length, &my_charset_latin1);
+  const Security_context *sctx= &thd->main_security_ctx;
+  char header[256];
+  int len;
+
+  mysql_mutex_lock(&LOCK_thread_count);
+
+  len= my_snprintf(header, sizeof(header),
+                   "MySQL thread id %lu, OS thread handle 0x%lx, query id %lu",
+                   thd->thread_id, (ulong) thd->real_id, (ulong) thd->query_id);
+  str.length(0);
+  str.append(header, len);
+
+  if (sctx->host)
+  {
+    str.append(' ');
+    str.append(sctx->host);
+  }
+
+  if (sctx->ip)
+  {
+    str.append(' ');
+    str.append(sctx->ip);
+  }
+
+  if (sctx->user)
+  {
+    str.append(' ');
+    str.append(sctx->user);
+  }
+
+  /* Don't wait if LOCK_thd_data is used as this could cause a deadlock */
+  if (!mysql_mutex_trylock(&thd->LOCK_thd_data))
+  {
+    if (const char *info= thread_state_info(thd))
+    {
+      str.append(' ');
+      str.append(info);
+    }
+
+    if (thd->query())
+    {
+      if (max_query_len < 1)
+        len= thd->query_length();
+      else
+        len= MY_MIN(thd->query_length(), max_query_len);
+      str.append('\n');
+      str.append(thd->query(), len);
+    }
+    mysql_mutex_unlock(&thd->LOCK_thd_data);
+  }
+  mysql_mutex_unlock(&LOCK_thread_count);
+
+  if (str.c_ptr_safe() == buffer)
+    return buffer;
+
+  /*
+    We have to copy the new string to the destination buffer because the string
+    was reallocated to a larger buffer to be able to fit.
+  */
+  DBUG_ASSERT(buffer != NULL);
+  length= MY_MIN(str.length(), length-1);
+  memcpy(buffer, str.c_ptr_quick(), length);
+  /* Make sure that the new string is null terminated */
+  buffer[length]= '\0';
+  return buffer;
+}