C/C++ with Gearman (as worker)

The document is very vague about how to register a function. It turned out that the prototype/signature of the function gearman_worker_fn is very import:

typedef void*( gearman_worker_fn)(gearman_job_st *job, void *context, size_t *result_size, gearman_return_t *ret_ptr)

And since all the online document links are broken, I had to create using Doxygen, under folder /usr/local/include/libgearman-1.0

#include <iostream>
#include <libgearman/gearman.h>
#include <cstring>

using namespace std;

 void* gworker_fn_demon(gearman_job_st *job, void *context, size_t *result_size, gearman_return_t *ret_ptr)
{
   auto jobptr = gearman_job_workload(job);//this takes the data from the client
   if (jobptr) std::cout << "job: " << (char*) jobptr << std::endl;
  *ret_ptr = GEARMAN_SUCCESS ;
  *result_size = 6;

  cout<<"job received"<<endl;
  //char* result = new char[100];//bug here: free/new mismatch reported from valgrind
char* result = (char*)malloc(100 * sizeof(char));
for(int ii = 0; ii < 4; ++ii){
  result[ii] = 'a' + ii;
 }
 result[4] = '\n';
 result[5] = '\0';
 return result;//the memory is freed at client side

 }


int main()
{
 auto status_print = [](gearman_return_t gserver_code){
   cout<<gserver_code<< " --  "; 
   if (gearman_success(gserver_code)) cout<<"success";
   if (gearman_failed(gserver_code)) cout<<"failed";
   if (gearman_continue(gserver_code)) cout<<"continue";
   cout<<endl;
 };

 gearman_worker_st* gworker = gearman_worker_create(NULL);
 

 
 const char* ghost = "127.0.0.1";
 in_port_t gport = 4730;

 gearman_return_t gs_code = gearman_worker_add_server(gworker, ghost, gport);

 status_print(gs_code);


 const char* function_name = "wwcc";
 unsigned timeout = 0;
 void * job_context = NULL;

 gs_code = gearman_worker_add_function(gworker,function_name, timeout, gworker_fn_demon, job_context);

 status_print(gs_code);



 gs_code = gearman_worker_work(gworker);

 status_print(gs_code);

 

 gearman_worker_free(gworker);


 cout<<"done"<<endl;
 return 0;
}