[BUG] The test TestIPv6.v6_calls_v4 hangs on FreeBSD

[yurivict]

IPv6-IPv4 mapping works differently on FreeBSD, this is probably the reason.

[maxsharabayko]

Related Issue #1972.

[maxsharabayko]

IPv6-IPv4 mapping works differently on FreeBSD, this is probably the reason.

@yurivict Could you please describe the difference or reference something to read?

[maxsharabayko]

From #2390:

105/218 Test #105: TestIPv6.v6_calls_v4 ................................***Failed    3.05 sec
Running main() from /disk-samsung/freebsd-ports/www/srt/work/.build/googletest/googletest-src/googletest/src/gtest_main.cc
Note: Google Test filter = TestIPv6.v6_calls_v4
[==========] Running 1 test from 1 test case.
[----------] Global test environment set-up.
[----------] 1 test from TestIPv6
[ RUN      ] TestIPv6.v6_calls_v4
Calling: 0::FFFF:127.0.0.1(IPv6)
/disk-samsung/freebsd-ports/www/srt/work/srt-1.5.0/test/test_ipv6.cpp:58: Failure
Expected: (connect_res) != (SRT_ERROR), actual: -1 vs -1
srt_connect() failed with: Connection setup failure: connection timed out
CALLER Sock name: : :::27781 (IPv6)
CALLER Peer name: : :::27781 (IPv6)
08:25:33.363202/T0x801012000*E:SRT.cn: srt_accept: listener socket @699377275 is already closed
/disk-samsung/freebsd-ports/www/srt/work/srt-1.5.0/test/test_ipv6.cpp:78: Failure
Expected: (accepted_sock) != (SRT_INVALID_SOCK), actual: -1 vs -1
accept() failed with: Connection setup failure: socket closed during operation
/disk-samsung/freebsd-ports/www/srt/work/srt-1.5.0/test/test_ipv6.cpp:190: Failure
Expected equality of these values:
  sa_accepted.str()
    Which is: "unknown:0"
  "127.0.0.1:4200"
[  FAILED  ] TestIPv6.v6_calls_v4 (3042 ms)
[----------] 1 test from TestIPv6 (3042 ms total)

[----------] Global test environment tear-down
[==========] 1 test from 1 test case ran. (3043 ms total)
[  PASSED  ] 0 tests.
[  FAILED  ] 1 test, listed below:
[  FAILED  ] TestIPv6.v6_calls_v4

 1 FAILED TEST

Version: 1.5.0
clang-13
FreeBSD 13.1

[yurivict]

@maxsharabayko

Could you please describe the difference or reference something to read?

On Linux ipv6 is mapped to ipv4 by default. On FreeBSD it is not.

The net.inet6.ip6.v6only sysctl value control this. Default is 1 (no mapping). Alternative is 0 (mapping, like in Linux).

Another way to control the same option is: ipv6_ipv4mapping=YES in /etc/rc.conf

[maxsharabayko]

@yurivict
PR #2420 (merged to the master) should resolve the issue. Please feel free to reopen if it has not.