c++ - "Failed writing body" CURLOPT_WRITEDATA -

the below code response server using wsdl, here problem curl returns response unable print it.

error:

failed writing body failed writing data

#include<stdio.h> #include<string.h> #include"../include/curl.h"  size_t write_data(void *ptr, size_t size, size_t count, void *stream) {       /* ptr - string variable.       stream - data chuck received */       printf("%.*s", size, (char*)stream); }   int main() {     int res=0,i=0;     char buffer[4098]="",buff[128]="",buf[256]="",buf7[30]="",buf6[30]="",buf5[30]="";     char machineid[]="subani";     char filename1[50]="";     int refno=0,paymode=0,taxtype=0;     file *fbc;      memset(filename1,0,sizeof(filename1));     sprintf(filename1,"/mnt/jffs2/response_details1.xml");     lk_dispclr();     lk_disptext(1,0,(unsigned char *)"sending request",0);     lk_disptext(2,0,(unsigned char *)"please wait",0);     memset(buffer,0,sizeof(buffer));      sprintf(buffer,"<?xml version=\"1.0\" encoding=\"utf-8\"?>\                         <soap:envelope xmlns:soap=\"http://www.w3.org/2003/05/soap-envelope\" xmlns:log=\"http://wsdlclassess.application.sims.test.com\">\                         <soap:header>\                         </soap:header>\                         <soap:body>\                         <log:loginmethod>\                         <log:loginid>%s</log:loginid>\                         <log:password>%s</log:password>\                         </log:loginmethod>\                         </soap:body>\                         </soap:envelope>","raja","test");       res=get_file1(buffer,filename1);       return 0; }   int get_file1(char *buffer,char *filename) {     curl *curl;     curlcode res;     struct curl_slist *headers = null;     file *out_fd = (file *) 0;     char errorbuf[300] = "",tmpbuff[128]="";     char errmsg[256];     int timeout=120;   //default timeout = 2 mins     int buffer_size = 0;     char urlbuff[256]="";     char mstr[10240];      memset(urlbuff,0,sizeof(urlbuff));         memset(tmpbuff,0,sizeof(tmpbuff));     buffer_size = strlen(buffer);          strcpy(tmpbuff,"http://10.10.1.111:8081/test_server/services/application?wsdl");              tmpbuff[strlen(tmpbuff)]='\0';     curl = curl_easy_init();     if(curl)     {         out_fd = fopen (filename, "w");         curl_easy_setopt(curl, curlopt_file, out_fd);         printf("%s:sign-in request\n", __func__);         headers = curl_slist_append(headers, "content-type:application/soap+xml; charset=utf-8; action=\"http://wsdlclassess.application.sims.test.com/loginmethod\"");          curl_easy_setopt(curl, curlopt_url, tmpbuff);         curl_easy_setopt(curl, curlopt_noprogress, 0);         curl_easy_setopt(curl, curlopt_verbose, 1);          curl_easy_setopt(curl, curlopt_httpheader, headers);         curl_easy_setopt(curl, curlopt_writefunction, write_data);      curl_easy_setopt(curl, curlopt_writedata, mstr);           curl_easy_setopt(curl, curlopt_postfieldsize, buffer_size);         curl_easy_setopt(curl, curlopt_postfields, buffer);          curl_easy_setopt(curl, curlopt_verbose, 1l);         curl_easy_setopt(curl, curlopt_timeout, timeout);         curl_easy_setopt(curl, curlopt_errorbuffer,errmsg);          printf("the server%s:performing transaction.....\n",__func__);         res = curl_easy_perform(curl);         printf("res=after culreasey perform%d\n",res);         curl_slist_free_all(headers);         curl_easy_cleanup(curl);         printf("\nerrorbuf:%s\n",errmsg);         fclose(out_fd);         if(curle_ok != res)         {             puts("error occured is\n" );             //ppp_close();             return -1;         }     }      return 0; } 

the error don't return correct value function, in fact don't return anything.

also, data provided function first ptr argument.

---

i agree documentation not clear, says:

the size of the data pointed ptr size multiplied nmemb, not 0 terminated.

the above line (emphasis mine) tells data in ptr first argument in function declaration provided in documentation.

the documentation also states:

return number of bytes taken care of. if amount differs amount passed function, it'll signal error library. abort transfer , return curle_write_error.

you don't return value function, , have undefined behavior seemingly random value being returned causing whole operation fail. fix should return size * count.

you uses size print string, size of underlying type used (probably 1), count variable number of characters read curl. working, without invoking more undefined behavior (since data not terminated) should call printf like:

printf("%*.*s", size * count, size * count, ptr);