+
+/* Returns the number of days in the specified month. */
+int
+calendar_days_in_month (int y, int m)
+{
+ static const int days_per_month[12]
+ = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
+
+ assert (m >= 1 && m <= 12);
+ return m == 2 && is_leap_year (y) ? 29 : days_per_month[m - 1];
+}