A fix and test case for bug#6058 "Prepared statements return '0000-00-00'

(date) as empty  string": preserve time type (date, time, or datetime) for
zero dates, times, and datetimes.


libmysql/libmysql.c:
  A fix for bug#6058 "Prepared statements return '0000-00-00' (date) as empty
   string": preserve time type (date, time, or datetime) for zero 
  dates, times, and datetimes.
tests/client_test.c:
  A test case for Bug#6058, the existing tests required some adjustments too.

libmysql/libmysql.c

@@ -3221,12 +3221,12 @@ static void read_binary_time(MYSQL_TIME *tm, uchar **pos)
     tm->second_part= (length > 8) ? (ulong) sint4korr(to+8) : 0;
 
     tm->year= tm->month= 0;
-    tm->time_type= MYSQL_TIMESTAMP_TIME;
 
     *pos+= length;
   }
   else
     set_zero_time(tm);
+  tm->time_type= MYSQL_TIMESTAMP_TIME;
 }
 
 static void read_binary_datetime(MYSQL_TIME *tm, uchar **pos)
@@ -3251,12 +3251,12 @@ static void read_binary_datetime(MYSQL_TIME *tm, uchar **pos)
     else
       tm->hour= tm->minute= tm->second= 0;
     tm->second_part= (length > 7) ? (ulong) sint4korr(to+7) : 0;
-    tm->time_type= MYSQL_TIMESTAMP_DATETIME;
 
     *pos+= length;
   }
   else
     set_zero_time(tm);
+  tm->time_type= MYSQL_TIMESTAMP_DATETIME;
 }
 
 static void read_binary_date(MYSQL_TIME *tm, uchar **pos)
@@ -3273,12 +3273,12 @@ static void read_binary_date(MYSQL_TIME *tm, uchar **pos)
     tm->hour= tm->minute= tm->second= 0;
     tm->second_part= 0;
     tm->neg= 0;
-    tm->time_type= MYSQL_TIMESTAMP_DATE;
 
     *pos+= length;
   }
   else
     set_zero_time(tm);
+  tm->time_type= MYSQL_TIMESTAMP_DATE;
 }
 
 

tests/client_test.c

@@ -3439,7 +3439,7 @@ static void test_fetch_date()
   MYSQL_STMT *stmt;
   uint       i;
   int        rc, year;
-  char       date[25], time[25], ts[25], ts_4[15], ts_6[20], dt[20];
+  char       date[25], time[25], ts[25], ts_4[25], ts_6[20], dt[20];
   ulong      d_length, t_length, ts_length, ts4_length, ts6_length,
              dt_length, y_length;
   MYSQL_BIND bind[8];
@@ -3549,8 +3549,8 @@ static void test_fetch_date()
   DIE_UNLESS(strcmp(dt, "2010-07-10 00:00:00") == 0);
   DIE_UNLESS(dt_length == 19);
 
-  DIE_UNLESS(ts_4[0] == '\0');
-  DIE_UNLESS(ts4_length == 0);
+  DIE_UNLESS(strcmp(ts_4, "0000-00-00 00:00:00") == 0);
+  DIE_UNLESS(ts4_length == strlen("0000-00-00 00:00:00"));
 
   DIE_UNLESS(strcmp(ts_6, "1999-12-29 00:00:00") == 0);
   DIE_UNLESS(ts6_length == 19);
@@ -10548,7 +10548,7 @@ static void test_bug6049()
   MYSQL_RES *res;
   MYSQL_ROW row;
   const char *stmt_text;
-  char *buffer[30];
+  char buffer[30];
   ulong length;
   int rc;
 
@@ -10577,6 +10577,52 @@ static void test_bug6049()
   rc= mysql_stmt_fetch(stmt);
   DIE_UNLESS(rc == 0);
 
+  printf("Result from query: %s\n", row[0]);
+  printf("Result from prepared statement: %s\n", (char*) buffer);
+
+  DIE_UNLESS(strcmp(row[0], (char*) buffer) == 0);
+
+  mysql_free_result(res);
+  mysql_stmt_close(stmt);
+}
+
+
+static void test_bug6058()
+{
+  MYSQL_STMT *stmt;
+  MYSQL_BIND bind[1];
+  MYSQL_RES *res;
+  MYSQL_ROW row;
+  const char *stmt_text;
+  char buffer[30];
+  ulong length;
+  int rc;
+
+  myheader("test_bug6058");
+
+  stmt_text= "SELECT CAST('0000-00-00' AS DATE)";
+
+  rc= mysql_real_query(mysql, stmt_text, strlen(stmt_text));
+  myquery(rc);
+  res= mysql_store_result(mysql);
+  row= mysql_fetch_row(res);
+
+  stmt= mysql_stmt_init(mysql);
+  rc= mysql_stmt_prepare(stmt, stmt_text, strlen(stmt_text));
+  check_execute(stmt, rc);
+  rc= mysql_stmt_execute(stmt);
+  check_execute(stmt, rc);
+
+  bzero(bind, sizeof(bind));
+  bind[0].buffer_type    = MYSQL_TYPE_STRING;
+  bind[0].buffer         = &buffer;
+  bind[0].buffer_length  = sizeof(buffer);
+  bind[0].length         = &length;
+
+  mysql_stmt_bind_result(stmt, bind);
+  rc= mysql_stmt_fetch(stmt);
+  DIE_UNLESS(rc == 0);
+
   printf("Result from query: %s\n", row[0]);
   printf("Result from prepared statement: %s\n", buffer);
 
@@ -10587,6 +10633,7 @@ static void test_bug6049()
 }
 
 
+
 /*
   Read and parse arguments and MySQL options from my.cnf
 */
@@ -10898,6 +10945,7 @@ int main(int argc, char **argv)
     test_bug5315();         /* check that mysql_change_user closes all
                                prepared statements */
     test_bug6049();         /* check support for negative TIME values */
+    test_bug6058();         /* check support for 0000-00-00 dates */
     /*
       XXX: PLEASE RUN THIS PROGRAM UNDER VALGRIND AND VERIFY THAT YOUR TEST
       DOESN'T CONTAIN WARNINGS/ERRORS BEFORE YOU PUSH.