Add some TCP constants

[Fensteer]

Add some TCP constants according to the sources : https://github.com/freebsd/freebsd/blob/master/sys/netinet/tcp.h#L164

[rust-highfive]

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[asomers]

Did you check the DragonflyBSD sources? I bet that many of these symbols are defined identically there. If so, they belong in src/unix/bsd/freebsdlike/mod.rs. Unless, of course, NetBSD and OpenBSD also define them identically, in which case they can go in src/unix/bsd/mod.rs.

[Fensteer]

I tried to put it in src/unix/bsd/mod.rs but darwin targets failed: https://travis-ci.org/rust-lang/libc/builds/459839121
Dragonfly doesn't defined the same constants: https://github.com/DragonFlyBSD/DragonFlyBSD/blob/e7ab884bd49753f8884eb597d10d6569a08fa0df/sys/netinet/tcp_var.h#L164

[asomers]

That's the wrong file. You want tcp.h, not tcp_var.h. Dragonfly does define some of the same constants.
https://github.com/DragonFlyBSD/DragonFlyBSD/blob/e7ab884bd49753f8884eb597d10d6569a08fa0df/sys/netinet/tcp.h

[Fensteer]

Thanks for the file. I factor common TCP variables between different OS.
Sources:
https://github.com/DragonFlyBSD/DragonFlyBSD/blob/master/sys/netinet/tcp.h#L156
https://github.com/freebsd/freebsd/blob/master/sys/netinet/tcp.h#L164
https://ftp.netbsd.org/pub/NetBSD/NetBSD-current/src/sys/netinet/tcp.h
https://github.com/openbsd/src/blob/master/sys/netinet/tcp.h#L126
https://github.com/bitrig/bitrig/blob/master/sys/netinet/tcp.h

[Fensteer]

Done, I tried to add TCP_CA_NAME_MAX but it's not available in userspace so I removed it.

[gnzlbg]

Could you rebase ?

[Fensteer]

Done, I squashed the commits

[gnzlbg]

@bors: r+

[bors]

📌 Commit 32a7d17 has been approved by gnzlbg

[bors]

⌛ Testing commit 32a7d17 with merge 914e50a...

[bors]

☀️ Test successful - status-appveyor, status-travis
Approved by: gnzlbg
Pushing 914e50a to master...

[semarie]

FYI, it broke the build on OpenBSD (there is no CI). I am working on unbreak it

[gnzlbg]

Damn. Would it be possible to contribute an OpenBSD build bot to CI similar to how the FreeBSD build bot works ?

[asomers]

@gnzlbg Are you thinking of Nix's buildbot? libc doesn't use buildbot, only Travis. libc's FreeBSD builder runs in QEMU on Travis. AFAIK the same technique should be possible for OpenBSD.

[semarie]

for FreeBSD, the CI does a crosscompilation from linux to freebsd, and run the executable via qemu. Last time I tried to do crosscompilation from linux to openbsd it was really difficult. Maybe it could be tested again as now we recently switched to clang + ld.lld.

[gnzlbg]

@asomers no I was thinking of what @semarie mentions, cross compiling from linux to OpenBSD and then running the binaries under qemu.