BIND libresolv allows values from 0 to 15.
For invalid values and negative numbers, 0 is used.
For numbers greater than 15, 15 is used.
Fixes#15419
Change-Id: I1009bc119c3e87919bcb55a80a35532e9fc3ba52
Reviewed-on: https://go-review.googlesource.com/24901
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Avoids some extra work and string concatenation at query time.
benchmark old allocs new allocs delta
BenchmarkGoLookupIP-32 154 150 -2.60%
BenchmarkGoLookupIPNoSuchHost-32 446 442 -0.90%
BenchmarkGoLookupIPWithBrokenNameServer-32 564 568 +0.71%
benchmark old bytes new bytes delta
BenchmarkGoLookupIP-32 10824 10704 -1.11%
BenchmarkGoLookupIPNoSuchHost-32 43140 42992 -0.34%
BenchmarkGoLookupIPWithBrokenNameServer-32 46616 46680 +0.14%
BenchmarkGoLookupIPWithBrokenNameServer's regression appears to be
because it's actually only performing 1 LookupIP call, so the extra
work done parsing the DNS config file doesn't amortize as well as for
BenchmarkGoLookupIP or BenchmarkGoLOokupIPNoSuchHost, which perform
2000+ LookupIP calls per run.
Update #15473.
Change-Id: I98c8072f2f39e2f2ccd6c55e9e9bd309f5ad68f8
Reviewed-on: https://go-review.googlesource.com/22571
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Instead of keeping the desired number of seconds and converting to
time.Duration for every query, convert to time.Duration when
building the config.
Updates #15473
Change-Id: Ib24c050b593b3109011e359f4ed837a3fb45dc65
Reviewed-on: https://go-review.googlesource.com/22548
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
This change simplifies unnecessarily redundant error messages in tests.
There's no need to worry any more because package APIs now return
consistent, self-descriptive error values.
Alos renames ambiguous test functions and makes use of test tables.
Change-Id: I7b61027607c4ae2a3cf605d08d58cf449fa27eb2
Reviewed-on: https://go-review.googlesource.com/9662
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Mikio Hara <mikioh.mikioh@gmail.com>
Per resolv.conf man page, "If this file does not exist, only the name
server on the local machine will be queried."
This behavior also occurs if file is present but unreadable,
or if no nameservers are listed.
Fixes#10566
Change-Id: Id5716da0eae534d5ebfafea111bbc657f302e307
Reviewed-on: https://go-review.googlesource.com/9380
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
If the machine's network configuration files (resolv.conf,
nsswitch.conf) don't have any unsupported options, prefer Go's DNS
resolver, which doesn't have the cgo & thread over.
It means users can have more than 500 DNS requests outstanding (our
current limit for cgo lookups) and not have one blocked thread per
outstanding request.
Discussed in thread https://groups.google.com/d/msg/golang-dev/2ZUi792oztM/Q0rg_DkF5HMJ
Change-Id: I3f685d70aff6b47bec30b63e9fba674b20507f95
Reviewed-on: https://go-review.googlesource.com/8945
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
