MFC:

MFC:

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	r317923 | n_hibma | 2017-05-07 23:11:28 +0200 (Sun, 07 May 2017) | 8 lines

	Fix the output of very large rebind, renew and lease time options in
	lease file.

	Some routers set very large values for rebind time (Netgear) and these
	are erroneously reported as negative in the leasefile. This was due to a
	wrong printf format specification of %ld for an unsigned long on 32-bit
	platforms.

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	r317915 | n_hibma | 2017-05-07 21:59:37 +0200 (Sun, 07 May 2017) | 16 lines

	Fix handling of large DHCP expiry values.

	They would overflow a signed 32-bit time_t on 32 bit architectures. This
	was taken care of, but a compiler optimisation makes this behave
	erratically. This could be resolved by adding a -fwrapv flag, but
	instead we can check the value before adding the current timestamp to
	it.

	In the lease file values are still wrong though:

		option dhcp-rebinding-time -644245096;

PR:		218980