On Request Body

Called by the µC/HTTP-client core to retrieve from the application the body data to put in the ongoing HTTP Request.

The parameter HTTPc_PARAM_TYPE_REQ_BODY_HOOK must be set up using the function HTTPc_ReqSetParam() for the hook function to be called. This hook function is used for both the Standard Transfer (content length of body is specified) and for the Chunked Transfer Encoding.

This hook function gives the choice to set the pointer to the application data (with p_data argument) that the µC/HTTP-client stack will take care of transferring; or to directly copy the data in the HTTP transmit buffer (with p_buf argument).

Prototype

CPU_BOOLEAN  HTTPc_ReqBodyHook (HTTPc_CONN_OBJ   *p_conn_obj,
                                HTTPc_REQ_OBJ    *p_req_obj,
                                void            **p_data,
                                CPU_CHAR         *p_buf,
                                CPU_INT16U       *p_buf_len  
                                CPU_INT16U       *p_data_len);

Arguments

p_conn_obj

Pointer to the current HTTPc Connection Object.

p_req_obj

Pointer to the current HTTPc Request Object.

p_data

Variable that will received the pointer to the data chunk to include in the HTTP request.

p_buf

Pointer to the HTTP transmit buffer.

buf_len

Length remaining in the HTTP transmit buffer.

p_data_len

Length of the data chunk.

Return Values

DEF_YES, if all the data to transmit have been passed by the application.

DEF_NO, if data to transmit remains to be passed by the application (Hook function will be called again).

Required Configuration

None.

Notes / Warnings

The data to transmit MUST stay valid until the HTTP transaction is completed.

Example Template

Listing - Request Body Callback Function Example Code

CPU_CHAR  AppHTTPc_ReqBodyBuf[1024];


static  CPU_BOOLEAN  HTTPc_ReqBodyHook (HTTPc_CONN_OBJ   *p_conn,
                                        HTTPc_REQ_OBJ    *p_req,
                                        void            **p_data,
                                        CPU_CHAR         *p_buf,
                                        CPU_INT16U        buf_len,
                                        CPU_INT16U       *p_data_len)
{
    CPU_SIZE_T  data_len;

    data_len   = App_ReadDataStream(&AppHTTPc_ReqBodyBuf);   /* Theoretical application's function to read a stream of data and  ... */
                                                             /* ... copy it in the buffer and return the length of data copied.      */

   *p_data     = &AppHTTPc_ReqBodyBuf;
   *p_data_len = data_len;

    if (data_len == 0) {
        return (DEF_YES);
    } else {
        return (DEF_NO);
    }
}