#include <mysql.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <pthread.h>
#include <string.h>
     
MYSQL *db_connect(const char *dbname);
void db_disconnect(MYSQL *db);
void db_do_query(MYSQL *db, const char *query);
static void die(MYSQL *db, char *fmt, ...);
     
const char *server_groups[] = {
  "test_libmysqld_SERVER", "embedded", "server", NULL
};

//
////////////////////////////////////////////////////////////////////////////
// Error Helper Function
//
////////////////////////////////////////////////////////////////////////////
int Error( MYSQL* _mysql ) {
  int    errorCode     = (int)mysql_errno(_mysql);
  const char *mySQLMessage = mysql_error(_mysql);            
  printf("\n%d - %s\n", errorCode, mySQLMessage);
  return (int)errorCode;
}

/********************************************************
* process the stmt result set                           *
*********************************************************/
#define MAX_RES_FIELDS 50
#define MAX_FIELD_DATA_SIZE 255

uint my_process_stmt_result(MYSQL_STMT *stmt)
{
  int         field_count;
  uint        row_count= 0;
  MYSQL_BIND  buffer[MAX_RES_FIELDS];
  MYSQL_FIELD *field;
  MYSQL_RES   *result;
  char        data[MAX_RES_FIELDS][MAX_FIELD_DATA_SIZE];
  ulong       length[MAX_RES_FIELDS];
  my_bool     is_null[MAX_RES_FIELDS];
  int         rc, i;

  if (!(result= mysql_get_metadata(stmt))) /* No meta info */
  {
    while (!mysql_fetch(stmt)) 
      row_count++;
    return row_count;
  }
  
  field_count= mysql_num_fields(result);
  for(i=0; i < field_count; i++)
  {
    buffer[i].buffer_type= MYSQL_TYPE_STRING;
    buffer[i].buffer_length= MAX_FIELD_DATA_SIZE;
    buffer[i].length= &length[i];
    buffer[i].buffer= (char*) data[i];
    buffer[i].is_null= &is_null[i];
  }

  rc= mysql_bind_result(stmt,buffer);

  rc= mysql_stmt_store_result(stmt);

  mysql_field_seek(result, 0);  
  while (mysql_fetch(stmt) == 0)
  {    
    fputc('\t',stdout);
    fputc('|',stdout);
    
    mysql_field_seek(result,0);
    for (i=0; i < field_count; i++)
    {
      field = mysql_fetch_field(result);
      if (is_null[i])
        fprintf(stdout, " %-*s |", (int) field->max_length, "NULL");
      else if (length[i] == 0)
      {
        data[i][0]='\0';  /* unmodified buffer */
        fprintf(stdout, " %*s |", (int) field->max_length, data[i]);
      }
      else if (IS_NUM(field->type))
        fprintf(stdout, " %*s |", (int) field->max_length, data[i]);
      else
        fprintf(stdout, " %-*s |", (int) field->max_length, data[i]);
    }
    fputc('\t',stdout);
    fputc('\n',stdout);
    row_count++;
  }

  fprintf(stdout,"\n\t%d %s returned\n", row_count, 
                 row_count == 1 ? "row" : "rows");
  mysql_free_result(result);
  return row_count;
}

static void test_subselect(MYSQL *mysql)
{
  MYSQL_STMT *stmt;
  MYSQL_BIND bind[3];
  char buffer[3][10];
  int rc, i;
  char query[1000];
  unsigned long lengths[3];
  

  strcpy(query, "SELECT SQL_BUFFER_RESULT "
	 "(SELECT COUNT(DISTINCT b) FROM t1 GROUP BY t1.a LIMIT 1) "
	 "FROM t1,t2 WHERE t1.a=t2.b");


  db_do_query(mysql, query); /* remove this line to get the bug with locks */

  stmt = mysql_prepare(mysql, query, strlen(query));
  

  for (i=0; i<10; i++)
  {
    rc= mysql_execute(stmt);
    my_process_stmt_result(stmt);
  }

  mysql_stmt_close(stmt);
}


int main(int argc, char **argv)
{
  MYSQL *mysql;

  mysql_server_init(argc, argv, (char **)server_groups);
  mysql= db_connect("test");
  test_subselect(mysql);
  mysql_server_end();
  return 0;

}

static void
die(MYSQL *db, char *fmt, ...)
{
  va_list ap;
  va_start(ap, fmt);
  vfprintf(stderr, fmt, ap);
  va_end(ap);
  (void)putc('\n', stderr);
  if (db)
    db_disconnect(db);
  exit(EXIT_FAILURE);
}
     
MYSQL *
db_connect(const char *dbname)
{
  MYSQL *db = mysql_init(NULL);

  if (!db)
    die(db, "mysql_init failed: no memory");
  /*
   * Notice that the client and server use separate group names.
   * This is critical, because the server will not accept the
   * client's options, and vice versa.
   */
  mysql_options(db, MYSQL_READ_DEFAULT_GROUP, "test_libmysqld_CLIENT");
  if (!mysql_real_connect(db, NULL, NULL, NULL, dbname, 0, NULL, 0))
    die(db, "mysql_real_connect failed: %s", mysql_error(db));
     
  return db;
}
     
void
db_disconnect(MYSQL *db)
{
  mysql_close(db);
}
     

void
db_do_query(MYSQL *db, const char *query)
{

  if (mysql_query(db, query) != 0)
    goto err;
   
  if (mysql_field_count(db) > 0)
    {
      MYSQL_RES   *res;
      MYSQL_ROW    row, end_row;
      int num_fields;
     
      if (!(res = mysql_store_result(db)))
	goto err;
      num_fields = mysql_num_fields(res);
      while ((row = mysql_fetch_row(res)))
	{
	  (void)fputs(">> ", stdout);
	  for (end_row = row + num_fields; row < end_row; ++row)
	    (void)printf("%s\t", *row ? (char*)*row : "NULL");
	  (void)fputc('\n', stdout);
	}
      (void)fputc('\n', stdout);
      mysql_free_result(res);
    }
  else
    (void)printf("Affected rows: %lld\n", mysql_affected_rows(db));
     
  return;
     
 err:
  die(db, "db_do_query failed: %s [%s]", mysql_error(db), query);
}