標(biāo)題: 要學(xué)好C語言你還得看STM32提供的庫 [打印本頁] 作者: 電子黑 時(shí)間: 2016-6-29 01:25 標(biāo)題: 要學(xué)好C語言你還得看STM32提供的庫 這倆typedef struct徹底顛覆了我對C語言知識。typedef struct _USER_STANDARD_REQUESTS
{
void (*User_GetConfiguration)(void); /* Get Configuration */
void (*User_SetConfiguration)(void); /* Set Configuration */
void (*User_GetInterface)(void); /* Get Interface */
void (*User_SetInterface)(void); /* Set Interface */
void (*User_GetStatus)(void); /* Get Status */
void (*User_ClearFeature)(void); /* Clear Feature */
void (*User_SetEndPointFeature)(void); /* Set Endpoint Feature */
void (*User_SetDeviceFeature)(void); /* Set Device Feature */
void (*User_SetDeviceAddress)(void); /* Set Device Address */
}
USER_STANDARD_REQUESTS;
typedef struct _DEVICE_PROP
{
void (*Init)(void); /* Initialize the device */
void (*Reset)(void); /* Reset routine of this device */
/* Device dependent process after the status stage */
void (*Process_Status_IN)(void);
void (*Process_Status_OUT)(void);
/* Procedure of process on setup stage of a class specified request with data stage */
/* All class specified requests with data stage are processed in Class_Data_Setup
Class_Data_Setup()
responses to check all special requests and fills ENDPOINT_INFO
according to the request
If IN tokens are expected, then wLength & wOffset will be filled
with the total transferring bytes and the starting position
If OUT tokens are expected, then rLength & rOffset will be filled
with the total expected bytes and the starting position in the buffer
If the request is valid, Class_Data_Setup returns SUCCESS, else UNSUPPORT
CAUTION:
Since GET_CONFIGURATION & GET_INTERFACE are highly related to
the individual classes, they will be checked and processed here.
*/
RESULT (*Class_Data_Setup)(uint8_t RequestNo);
/* Procedure of process on setup stage of a class specified request without data stage */
/* All class specified requests without data stage are processed in Class_NoData_Setup
Class_NoData_Setup
responses to check all special requests and perform the request
CAUTION:
Since SET_CONFIGURATION & SET_INTERFACE are highly related to
the individual classes, they will be checked and processed here.
*/
RESULT (*Class_NoData_Setup)(uint8_t RequestNo);
/*Class_Get_Interface_Setting
This function is used by the file usb_core.c to test if the selected Interface
and Alternate Setting (uint8_t Interface, uint8_t AlternateSetting) are supported by
the application.
This function is writing by user. It should return "SUCCESS" if the Interface
and Alternate Setting are supported by the application or "UNSUPPORT" if they
are not supported. */
RESULT (*Class_Get_Interface_Setting)(uint8_t Interface, uint8_t AlternateSetting);
uint8_t* (*GetDeviceDescriptor)(uint16_t Length);
uint8_t* (*GetConfigDescriptor)(uint16_t Length);
uint8_t* (*GetStringDescriptor)(uint16_t Length);
uint8_t* RxEP_buffer;
uint8_t MaxPacketSize;
}DEVICE_PROP;
應(yīng)用分析：struct是一個(gè)結(jié)構(gòu)體，可以用來構(gòu)造數(shù)據(jù)類型。所以可以得知這兩個(gè)struct里面的數(shù)據(jù)不是函數(shù)，而是函數(shù)指針，即它是一個(gè)指針，指向一個(gè)函數(shù)。RESULT，uint8_t*，void是函數(shù)的返回值類型。