Crash when getting permanent subscriptions created with old Orion versions

[fgalan]

A bug was introduced by 1a49367 in PR #3084 around January 22nd, 2018 as part of issue #3004 implementation, in the 1.13.0 development cycle.

In particular the bug is due to this change:

-#define PERMANENT_SUBS_DATETIME ((int64_t) 9e18)
+#define PERMANENT_EXPIRES_DATETIME ((int64_t) 0x7FFFFFFFFFFFFFFF)

where:

(int64_t) 9e18               = 9000000000000000000
(int64_t) 0x7FFFFFFFFFFFFFFF = 9223372036854775807

What is happening is that permanent subscriptions created before 1.13.0 are using the first one, so now the following checking in Subscription::toJson():

  if (this->expires != PERMANENT_EXPIRES_DATETIME)
  {
    jh.addDate("expires", this->expires);
  }

is failing and activates the jh.addDate() even when subscription is permanent, so causing the crash (add addDate calls internally gmtime() with so large value and fails).

[fgalan]

Fixed by PR #3257