gabrielformiga/libpqnb

Postgres non-blocking libpq connection pool

libpqnb's Issues

Making single query

Hello, I can't seem to figure out how to make just one query. I only pool one query but it always ends up running the query more than once, and it is giving undefined behavior in that the amount of times that the query callback is called is random.

#include "poolInit.h"

#define CONNINFO "postgresql://info@localhost/dbname"
#define QUERY "SELECT * FROM users"
#define TEST_TIME_SEC 1
#define NUM_CONNECTIONS 32

struct query_counter { uint64_t count; PGresult *resRet;};
static void
test_print_res(PGresult *res)
{
  int num_fields = PQnfields(res);
  for (int i = 0; i < num_fields; i++) {
      const int ftype = PQftype(res, i);
      printf("fname %s ftype %d\n", PQfname(res, i), ftype);
  }
  /* next, print out the rows */
  int num_rows = PQntuples(res);
  for (int i = 0; i < num_rows; i++) {
      for (int j = 0; j < num_fields; j++)
        printf("%s\t", PQgetvalue(res, i, j));
      printf("\n");
  }
}

struct PQNB_pool * getPool(){
  struct PQNB_pool *pool;
  pool = PQNB_pool_init(CONNINFO, NUM_CONNECTIONS);
  assert(NULL != pool);
  return pool;
}
int main(){
    struct PQNB_pool *pool = getPool();
    const union PQNB_pool_info *info;
  int epoll_fd, res;
  struct epoll_event ev, evs[1];
  struct query_counter counter;
  time_t end;
    info = PQNB_pool_get_info(pool, PQNB_INFO_EPOLL_FD);
      assert(NULL != info);
      assert(info->epoll_fd != -1);
      epoll_fd = epoll_create1(EPOLL_CLOEXEC);
      assert(epoll_fd != -1);
      ev.events = EPOLLIN;
      ev.data.ptr = NULL;
      res = epoll_ctl(epoll_fd, EPOLL_CTL_ADD, info->epoll_fd, &ev);
      assert(-1 != res);
      counter.count = 0;
    static bool flag = false;
void test_query_cb2(PGresult *res,
              void *user_data,
              char *error_msg,
              bool timeout)
{
  struct query_counter *queries_counter;

  /*
   * ignoring compiler warnings
   */
  (void) res;

  if (timeout)
    {
      printf("timeout\n");
      return;
    }

  if (NULL != error_msg)
    {
      printf("%s", error_msg);
      return;
    }

  if (PGRES_TUPLES_OK == PQresultStatus(res))
    {
flag = true;
      assert(NULL != user_data);
      queries_counter = user_data;
      queries_counter->count++;
      queries_counter->resRet = PQcopyResult(res, PG_COPYRES_TUPLES);
    }
  else
    printf("query failed\n");
}
    // filling query buffer
    while(-1 != PQNB_pool_query(pool, QUERY, test_query_cb2, &counter));
    while(!flag){
         res = epoll_wait(epoll_fd, evs, 1, 1000);
         if (res == -1)
            break;
        if(counter.count ==0 && !flag){
            int run = PQNB_pool_run(pool);
        if (run == -1){
          printf("run returned -1\n");
          //break;
          }
          }
    }
    test_print_res(counter.resRet);
    PQNB_pool_free(pool);
    printf("total queries: %ld\n", counter.count);
    return 0;
}

Any help is very much appreciated, this seems like a really nice library and I'd love to get it fully working.