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关于z-stack结构体默认对齐方式与强制转换问题,急,求大神回答

z-stack的结构体默认对齐方式是一字节吗?

在z-stack中可以将一般指针强制转换为结构体指针吗?

one Man:

回复 guozi zhou52:

搞不懂以下这两个结构体为什么可以转换

uint16 SampleApp_ProcessEvent( uint8 task_id, uint16 events )
{afIncomingMSGPacket_t * MSGpkt;if ( events & SYS_EVENT_MSG ){MSGpkt = (afIncomingMSGPacket_t *)osal_msg_receive( SampleApp_TaskID );while ( MSGpkt ){switch ( MSGpkt->hdr.event ){case KEY_CHANGE:SampleApp_HandleKeys( ((keyChange_t *)MSGpkt)->state, ((keyChange_t *)MSGpkt)->keys );break;1
typedef struct
{osal_event_hdr_t hdr;uint8state; // shiftuint8keys;// keys
} keyChange_t;typedef struct
{osal_event_hdr_t hdr;/* OSAL Message header */uint16 groupId;/* Message's group ID - 0 if not set */uint16 clusterId;/* Message's cluster ID */afAddrType_t srcAddr;/* Source Address, if endpoint is STUBAPS_INTER_PAN_EP,it's an InterPAN message */uint16 macDestAddr;/* MAC header destination short address */uint8 endPoint;/* destination endpoint */uint8 wasBroadcast;/* TRUE if network destination was a broadcast address */uint8 LinkQuality;/* The link quality of the received data frame */uint8 correlation;/* The raw correlation value of the received data frame */int8rssi;/* The received RF power in units dBm */uint8 SecurityUse;/* deprecated */uint32 timestamp;/* receipt timestamp from MAC */afMSGCommandFormat_t cmd; /* Application Data */
} afIncomingMSGPacket_t;

one Man:

回复 guozi zhou52:

两个结构体的成员不一样啊,会不会访问出错的?

guozi zhou52:

回复 one Man:

消息头一直,第一次转换 一般只取消息头信息

one Man:

回复 guozi zhou52:

 可以不可以这样理解:

MSGpkt = (afIncomingMSGPacket_t *)osal_msg_receive( SampleApp_TaskID );这个条语句只是接收到一个消息,还不知道是什么消息

switch ( MSGpkt->hdr.event )
{
        
  case KEY_CHANGE: //这里发现是一条按键消息,
    SampleApp_HandleKeys( ((keyChange_t *)MSGpkt)->state, ((keyChange_t *)MSGpkt)->keys );

那么上面接收到的消息的内容就是

typedef struct
{
  osal_event_hdr_t hdr;
  uint8  state; // shift
  uint8  keys;  // keys
} keyChange_t;
这个结构体的内容,如果按照

typedef struct
{
  osal_event_hdr_t hdr;     /* OSAL Message header */
  uint16 groupId;           /* Message's group ID – 0 if not set */
  uint16 clusterId;         /* Message's cluster ID */
  afAddrType_t srcAddr;     /* Source Address, if endpoint is STUBAPS_INTER_PAN_EP,
                               it's an InterPAN message */
  uint16 macDestAddr;       /* MAC header destination short address */
  uint8 endPoint;           /* destination endpoint */
  uint8 wasBroadcast;       /* TRUE if network destination was a broadcast address */
  uint8 LinkQuality;        /* The link quality of the received data frame */
  uint8 correlation;        /* The raw correlation value of the received data frame */
  int8  rssi;               /* The received RF power in units dBm */
  uint8 SecurityUse;        /* deprecated */
  uint32 timestamp;         /* receipt timestamp from MAC */
  afMSGCommandFormat_t cmd; /* Application Data */
} afIncomingMSGPacket_t;
这个结构体访问的话,其实中的uint16 groupId;就是
uint8  state; // shift
uint8  keys;  // keys
这两个变量的值?

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