Function thd_get_error_context_description

sql/sql_show.cc:11570–11637

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];
  size_t len;

  len= my_snprintf(header, sizeof(header),
                   "MariaDB thread id %u, OS thread handle %lu, query id %llu",
                   (uint)thd->thread_id, (ulong) thd->real_id, (ulonglong) thd->query_id);
  str.length(0);
  str.append(header, len);

  if (sctx->host)
  {
    str.append(' ');
    str.append(sctx->host, strlen(sctx->host));
  }

  if (sctx->ip)
  {
    str.append(' ');
    str.append(sctx->ip, strlen(sctx->ip));
  }

  if (sctx->user)
  {
    str.append(' ');
    str.append(sctx->user, strlen(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, strlen(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);
  }

  if (str.c_ptr_safe() == buffer)
    return buffer;

  /*