为消息添加参数及从消息中提取参数（DBus)

xmulqy

typedef struct{
  int id;
  int parent_id;
  char *mt_title;
}MSG_STRUCT;
static void* mt_query_dbus_message_get(DBusMessageIter *iter)
{
  DBusMessageIter array_iter;
  DBusMessageIter struct_iter;
  int num_attrs;
  int i;
  MSG_STRUCT *mt_table;  
  
  if(DBUS_TYPE_INT32 != dbus_message_iter_get_arg_type(iter))
  {
    fprintf(stderr, "There must be something wrong in the server.\n");
    exit(0);
  }
  dbus_message_iter_get_basic(iter, &num_attrs);
  dbus_message_iter_next(iter);
  dbus_message_iter_recurse(iter, &array_iter);
  mt_table = (MSG_STRUCT*)malloc(sizeof(MSG_STRUCT)*num_attrs);
  
  for(i = 0; i < num_attrs; i++)
  {
    if(dbus_message_iter_get_arg_type(&array_iter) == DBUS_TYPE_STRUCT)
    {
      dbus_message_iter_recurse(&array_iter, &struct_iter);
      dbus_message_iter_get_basic(&struct_iter,&(mt_table.id));
      dbus_message_iter_next(&struct_iter);
      dbus_message_iter_get_basic(&struct_iter,&(mt_table.parent_id));
      dbus_message_iter_next(&struct_iter);
      dbus_message_iter_get_basic(&struct_iter,&(mt_table.mt_title));
    // printf("get argument:%s\n",mt_table.mt_title);
    }
    dbus_message_iter_next(&array_iter);
  }
  mt_print_table(mt_table, num_attrs);
  free(mt_table);
}
/**
* Send the argument
*/
static void* mt_query_dbus_message_send(char**szResult, int iRow, int iColumn, DBusMessageIter *args)
{
  int i;
  DBusMessageIter struct_args;
  DBusMessageIter array_args;
  if(!dbus_message_iter_append_basic(args, DBUS_TYPE_INT32, &iRow))
  {
    fprintf(stderr,"Out Of Memory!\n");
    exit(0);
  }
  dbus_message_iter_open_container(args, DBUS_TYPE_ARRAY, "(iis)",&array_args);
  for(i = 1;i <= iRow; i++)
  {
    dbus_message_iter_open_container(&array_args, DBUS_TYPE_STRUCT, 0, &struct_args);
    int object_id;
    int parent_id;
    char **mt_title;
    object_id = atoi(szResult[i*iColumn+0]);
    parent_id = atoi(szResult[i*iColumn+2]);
    mt_title = &(szResult[i*iColumn+5]);
    if(!dbus_message_iter_append_basic(&struct_args,DBUS_TYPE_INT32,&object_id))
    {
      fprintf(stderr,"Out Of Memory!\n");
      exit(0);
    }
    if(!dbus_message_iter_append_basic(&struct_args,DBUS_TYPE_INT32,&parent_id))
    {
      fprintf(stderr,"Out Of Memory!\n");
      exit(0);
    }
    if(!dbus_message_iter_append_basic(&struct_args,DBUS_TYPE_STRING,mt_title))
    {
      fprintf(stderr,"Out Of Memory!\n");
      exit(0);
    }
    dbus_message_iter_close_container(&array_args,&struct_args);
  }
  dbus_message_iter_close_container(args, &array_args);
}
上面是两个调用了DBUS中和消息参数管理相关的几个主要API的函数，接下来将详细介绍这几个接口的调用方法。


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