Various buffers are allocated in an assumption that there would be
no more than 4 year digits. This might not be true on platforms
with 64-bit time_t, as 64-bit time_t is able to represent more than that.
Such dates with more than 4 year digits hardly make sense though, as
various date formats in use do not allow them anyway.
As such, all dates are now truncated by ngx_gmtime() to December 31, 9999.
This should have no effect on valid dates, though will prevent potential
buffer overflows on invalid ones.
days = t / 86400;
sec = t % 86400;
+ /*
+ * no more than 4 year digits supported,
+ * truncate to December 31, 9999, 23:59:59
+ */
+
+ if (days > 2932896) {
+ days = 2932896;
+ sec = 86399;
+ }
+
/* January 1, 1970 was Thursday */
wday = (4 + days) % 7;