#define ptr_valid(ptr, func) object_valid(ptr, func, #ptr)

typedef struct mypointer_t {
    char* name;
    ....
} mypointer_t;

static inline bool object_valid(const void *obj, const char *f,
        const char *t)
{
    if (!obj) {
        blog(LOG_DEBUG, "%s: Null '%s' parameter", f, t);
        return false;
    }

    return true;
}

const char* func(mypointer_t* t){
      return ptr_valid(t, "function_name") ?
              t->name : NULL;
}

mypointer_t* buildAPtr() {
    // Do some stuff and return a new mypointer_t* or NULL
}

int main(int argc, char** argv) {
    mypointer_t* myPointer = buildAPtr();
    std::string Kappa = func(myPointer);

    return 0;
}