Let's use size_t for numbers of entries in memory.
Let's use const wherever appropriate.
Drop `_server` suffix from function name where we don't have it for
similar other cases.
We always need to make them unions with a "struct cmsghdr" in them, so
that things properly aligned. Otherwise we might end up at an unaligned
address and the counting goes all wrong, possibly making the kernel
refuse our buffers.
Also, let's make sure we initialize the control buffers to zero when
sending, but leave them uninitialized when reading.
Both the alignment and the initialization thing is mentioned in the
cmsg(3) man page.
We need to use the CMSG_SPACE() macro to size the control buffers, not
CMSG_LEN(). The former is rounded up to next alignment boundary, the
latter is not. The former should be used for allocations, the latter for
encoding how much of it is actually initialized. See cmsg(3) man page
for details about this.
Given how confusing this is, I guess we don't have to be too ashamed
here, in most cases we actually did get this right.
Split out of #15457, let's see if this is the culprit of the CI failure.
(also setting green label here, since @keszybz already greenlit it in that other PR)
It's not that I think that "hostname" is vastly superior to "host name". Quite
the opposite — the difference is small, and in some context the two-word version
does fit better. But in the tree, there are ~200 occurrences of the first, and
>1600 of the other, and consistent spelling is more important than any particular
spelling choice.
When specifying `DHCPv4.SendOption=`, it is used by systemd-networkd to
set the value of that option within the DHCP request that is sent out.
This differs to setting `DHCPServer.SendOption=`, which will place all
the options together as suboptions into the vendor-specific information
(code 43) option.
This commit adds two new config options, `DHCPv4.SendVendorOption=` and
`DHCPServer.SendVendorOption=`. These both have the behaviour of the old
`DHCPServer.SendOption=` flag, and set the value of the suboption in the
vendor-specific information option.
The behaviour of `DHCPServer.SendOption=` is then changed to reflect
that of `DHCPv4.SendOption=`. It will set the value of the corresponding
option in the DHCP request.
Don't reset the conflict counter when trying a new pseudo random
address, so that after trying 10 addresses the londer timeout is used in
accordance with the RFC
Fixes#14299.