Commit Graph

16 Commits

Author SHA1 Message Date
Tom Thorogood 17c1bc6792
Eliminate lexer goroutines (#792)
* Eliminate zlexer goroutine

This replaces the zlexer goroutine and channels with a zlexer struct
that maintains state and provides a channel-like API.

* Eliminate klexer goroutine

This replaces the klexer goroutine and channels with a klexer struct
that maintains state and provides a channel-like API.

* Merge scan into zlexer and klexer

This does result in tokenText existing twice, but it's pretty simple
and small so it's not that bad.

* Avoid using text/scanner.Position to track position

* Track escape within zlexer.Next

* Avoid zl.commt check on space and tab in zlexer

* Track stri within zlexer.Next

* Track comi within zlexer.Next

There is one special case at the start of a comment that needs to be
handled, otherwise this is as simple as stri was.

* Use a single token buffer in zlexer

This is safe as there is never both a non-empty string buffer and a
non-empty comment buffer.

* Don't hardcode length of zl.tok in zlexer

* Eliminate lex.length field

This is always set to len(l.token) and is only queried in a few places.

It was added in 47cc5b052d without any
obvious need.

* Add whitespace to klexer.Next

* Track lex within klexer.Next

* Use a strings.Builder in klexer.Next

* Simplify : case in klexer.Next

* Add whitespace to zlexer.Next

* Change for loop style in zlexer.Next and klexer.Next

* Surface read errors in zlexer

* Surface read errors from klexer

* Remove debug line from parseKey

* Rename tokenText to readByte

* Make readByte return ok bool

Also change the for loop style to match the Next for loops.

* Make readByte errors sticky

klexer.Next calls readByte separately from within the loop. Without
readByte being sticky, an error that occurs during that readByte call
may be lost.

* Panic in testRR if the error is non-nil

* Add whitespace and unify field setting in zlexer.Next

* Remove eof fields from zlexer and klexer

With readByte having sticky errors, this no longer needed. zl.eof = true
was also in the wrong place and could mask an unbalanced brace error.

* Merge zl.tok blocks in zlexer.Next

* Split the tok buffer into separate string and comment buffers

The invariant of stri > 0 && comi > 0 never being true was broken when
x == '\n' && !zl.quote && zl.commt && zl.brace != 0 (the
"If not in a brace this ends the comment AND the RR" block).

Split the buffer back out into two separate buffers to avoid clobbering.

* Replace token slices with arrays in zlexer

* Add a NewRR benchmark

* Move token buffers into zlexer.Next

These don't need to be retained across Next calls and can be stack
allocated inside Next. This drastically reduces memory consumption as
they accounted for nearly half of all the memory used.

name      old alloc/op   new alloc/op   delta
NewRR-12    9.72kB ± 0%    4.98kB ± 0%  -48.72%  (p=0.000 n=10+10)

* Add a ReadRR benchmark

Unlike NewRR, this will use an io.Reader that does not implement any
methods aside from Read. In particular it does not implement
io.ByteReader.

* Avoid using a bufio.Reader for io.ByteReader readers

At the same time use a smaller buffer size of 1KiB rather than the
bufio.NewReader default of 4KiB.

name       old time/op    new time/op    delta
NewRR-12     11.0µs ± 3%     9.5µs ± 2%  -13.77%  (p=0.000 n=9+10)
ReadRR-12    11.2µs ±16%     9.8µs ± 1%  -13.03%  (p=0.000 n=10+10)

name       old alloc/op   new alloc/op   delta
NewRR-12     4.98kB ± 0%    0.81kB ± 0%  -83.79%  (p=0.000 n=10+10)
ReadRR-12    4.87kB ± 0%    1.82kB ± 0%  -62.73%  (p=0.000 n=10+10)

name       old allocs/op  new allocs/op  delta
NewRR-12       19.0 ± 0%      17.0 ± 0%  -10.53%  (p=0.000 n=10+10)
ReadRR-12      19.0 ± 0%      19.0 ± 0%     ~     (all equal)

ReadRR-12    11.2µs ±16%     9.8µs ± 1%  -13.03%  (p=0.000 n=10+10)

* Surface any remaining comment from zlexer.Next

* Improve comment handling in zlexer.Next

This both fixes a regression where comments could be lost under certain
circumstances and now emits comments that occur within braces.

* Remove outdated comment from zlexer.Next and klexer.Next

* Delay converting LF to space in braced comment

* Fixup TestParseZoneComments

* Remove tokenUpper field from lex

Not computing this for every token, and instead only
when needed is a substantial performance improvement.

name       old time/op    new time/op    delta
NewRR-12     9.56µs ± 0%    6.30µs ± 1%  -34.08%  (p=0.000 n=9+10)
ReadRR-12    9.93µs ± 1%    6.67µs ± 1%  -32.77%  (p=0.000 n=10+10)

name       old alloc/op   new alloc/op   delta
NewRR-12       824B ± 0%      808B ± 0%   -1.94%  (p=0.000 n=10+10)
ReadRR-12    1.83kB ± 0%    1.82kB ± 0%   -0.87%  (p=0.000 n=10+10)

name       old allocs/op  new allocs/op  delta
NewRR-12       17.0 ± 0%      17.0 ± 0%     ~     (all equal)
ReadRR-12      19.0 ± 0%      19.0 ± 0%     ~     (all equal)

* Update ParseZone documentation to match comment changes

The zlexer code was changed to return comments more often, so update the
ParseZone documentation to match.
2018-10-15 17:42:31 +10:30
Tom Thorogood 7f61c6631b
Fix dominikh/go-tools nits (#758)
* Remove unused functions and consts

* Address gosimple nits

* Address staticcheck nits

This excludes several that were intentional or weren't actual errors.

* Reduce size of lex struct

This reduces the size of the lex struct by 8 bytes from:
  lex.token string: 0-16 (size 16, align 8)
  lex.tokenUpper string: 16-32 (size 16, align 8)
  lex.length int: 32-40 (size 8, align 8)
  lex.err bool: 40-41 (size 1, align 1)
  lex.value uint8: 41-42 (size 1, align 1)
  padding: 42-48 (size 6, align 0)
  lex.line int: 48-56 (size 8, align 8)
  lex.column int: 56-64 (size 8, align 8)
  lex.torc uint16: 64-66 (size 2, align 2)
  padding: 66-72 (size 6, align 0)
  lex.comment string: 72-88 (size 16, align 8)
to:
  lex.token string: 0-16 (size 16, align 8)
  lex.tokenUpper string: 16-32 (size 16, align 8)
  lex.length int: 32-40 (size 8, align 8)
  lex.err bool: 40-41 (size 1, align 1)
  lex.value uint8: 41-42 (size 1, align 1)
  lex.torc uint16: 42-44 (size 2, align 2)
  padding: 44-48 (size 4, align 0)
  lex.line int: 48-56 (size 8, align 8)
  lex.column int: 56-64 (size 8, align 8)
  lex.comment string: 64-80 (size 16, align 8)

* Reduce size of response struct

This reduces the size of the response struct by 8 bytes from:
  response.msg []byte: 0-24 (size 24, align 8)
  response.hijacked bool: 24-25 (size 1, align 1)
  padding: 25-32 (size 7, align 0)
  response.tsigStatus error: 32-48 (size 16, align 8)
  response.tsigTimersOnly bool: 48-49 (size 1, align 1)
  padding: 49-56 (size 7, align 0)
  response.tsigRequestMAC string: 56-72 (size 16, align 8)
  response.tsigSecret map[string]string: 72-80 (size 8, align 8)
  response.udp *net.UDPConn: 80-88 (size 8, align 8)
  response.tcp net.Conn: 88-104 (size 16, align 8)
  response.udpSession *github.com/tmthrgd/dns.SessionUDP: 104-112 (size 8, align 8)
  response.writer github.com/tmthrgd/dns.Writer: 112-128 (size 16, align 8)
  response.wg *sync.WaitGroup: 128-136 (size 8, align 8)
to:
  response.msg []byte: 0-24 (size 24, align 8)
  response.hijacked bool: 24-25 (size 1, align 1)
  response.tsigTimersOnly bool: 25-26 (size 1, align 1)
  padding: 26-32 (size 6, align 0)
  response.tsigStatus error: 32-48 (size 16, align 8)
  response.tsigRequestMAC string: 48-64 (size 16, align 8)
  response.tsigSecret map[string]string: 64-72 (size 8, align 8)
  response.udp *net.UDPConn: 72-80 (size 8, align 8)
  response.tcp net.Conn: 80-96 (size 16, align 8)
  response.udpSession *github.com/tmthrgd/dns.SessionUDP: 96-104 (size 8, align 8)
  response.writer github.com/tmthrgd/dns.Writer: 104-120 (size 16, align 8)
  response.wg *sync.WaitGroup: 120-128 (size 8, align 8)
2018-09-27 04:02:05 +09:30
Miek Gieben dcdbddd810
ClassANY: don't convert CLASS255 to ANY (#618)
* ClassANY: don't convert CLASS255 to ANY

Class "ANY" is wireformat only. In zonefile you can use CLASS255, but
when String-ing we convert this into "ANY" which is wrong. I.e. this
means we can't read back our own update.

Bit of a kludge to work around this, as I'm not sure we can just remove
ANY from the ClassToString map.
2018-01-07 17:57:04 +00:00
Miek Gieben 3bbde607ac
relative include: now tested! (#602)
* relative include: now tested!

If you take the effort of creating includePath, actually use it when
opening the file. Now tested (again) with CoreDNS (with a zone file that
includes two others)

Failure to include leads to:

~~~
2017/12/07 16:47:00 plugin/file: /tmp/example.org: dns: failed to include `a/1include1.org' as `/tmp/a/1include1.org': "a/1include1.org" at line: 15:24
~~~

* dont change the error line
2017-12-07 17:12:20 +00:00
Miek Gieben c438b740fe
Allow $INCLUDE to reference relative file (#598)
When using a relative file in an $INCLUDE the file is referenced from
the cwd from the calling processes; this changes it to be down from the
view point where the file exists.

Code from https://github.com/miekg/dns/issues/537#issuecomment-342932962

Fixes #537
2017-12-06 22:03:54 +00:00
Miek Gieben 2a67631d76
cleanup: remove debug.Printf from scanner (#573)
Remove the debug.Printf stuff from scanner and some other style nits.
2017-11-17 10:48:42 +00:00
Miek Gieben cfe41281c2
txt parser: fix goroutine leak (#570)
* txt parser: fix goroutine leak

When a higher level (grammar or syntax) error was encountered the lower
level zlexer routine would be left open and trying to send more tokens
on the channel c. This leaks a goroutine, per failed parse...

This PR fixes this by signalling this error - by canceling a context -
retrieving any remaining items from the channel, so zlexer can return.

It also adds a goroutine leak test that can be re-used in other tests,
the TestParseBadNAPTR test uses this leak detector.

The private key parsing code had the same bug and is also fixed in this
PR.

Fixes #586
Fixes https://github.com/coredns/coredns/issues/1233

* sem not needed anymore
2017-11-17 10:47:28 +00:00
Miek Gieben b38dc3dcb7
Cleanup: gofmt -w -s *.go (#548)
Some renames of internal names to make go lint happier.
2017-11-03 16:15:35 +00:00
Richard Gibson eccf8bbe83 Correctly parse omitted TTLs and relative domains (#513)
* Fix $TTL handling
* Error when there is no TTL for an RR
* Fix relative name handling
* Error when a relative name is used without an origin (cf. https://tools.ietf.org/html/rfc1035#section-5.1 )

Fixes #484
2017-09-26 11:15:37 -04:00
Miek Gieben e420576857 scan: Fix $INCLUDE arguments to parseZone (#508)
When an $INCLUDE was seen the arguments to parseZone where in the wrong
order meaning the filename was used as the `neworigin` instead of the
actual origin we need.

Extend the testcase to check for the full name of the record.
2017-08-18 14:14:42 +01:00
Tim Esselens bbca4873b3 variable shadowing of token (#503)
* Added test for $INCLUDE statement parser in zone files

* FIX: localized l to switch statement, shadowed later call to os.Open(l.token)
2017-08-08 15:19:10 -07:00
Miek Gieben babbdab23a parsing: error on unbalanced braces (#489)
When done parsing, check if we have balanced braces, if not error out.

Fixes #488
2017-05-23 11:21:56 +01:00
Jon Nappi c862b7e359 Replace Atoi with ParseUint where appropriate (#470)
* replace Atoi with ParseUint where appropriate

* more Atoi replacements
2017-03-10 21:57:03 +00:00
Roland Bracewell Shoemaker 574f29b9d6 Always set tokenUpper when setting token (#403) 2016-10-03 15:10:26 +01:00
Michael Haro 1be7320498 Use t.Errorf in tests and make the error variable naming more consistent. (#367)
* Make the error variable always named err.

Sometimes the error variable was named 'err' sometimes 'e'.  Sometimes
'e' refered to an EDNS or string and not an error type.

* Use t.Errorf instead of t.Logf & t.Fail.
2016-06-09 07:00:08 +01:00
Miek Gieben 475ab80867 Remove (most) reflection
Remove the use of reflection when packing and unpacking, instead
generate all the pack and unpack functions using msg_generate.
This will generate zmsg.go which in turn calls the helper functions from
msg_helper.go.

This increases the speed by about ~30% while cutting back on memory
usage. Not all RRs are using it, but that will be rectified in upcoming
PR.

Most of the speed increase is in the header/question section parsing.
These functions *are* not generated, but straight forward enough. The
implementation can be found in msg.go.

The new code has been fuzzed by go-fuzz, which turned up some issues.

All files that started with 'z', and not autogenerated were renamed,
i.e. zscan.go is now scan.go.

Reflection is still used, in subsequent PRs it will be removed entirely.
2016-06-03 12:45:22 +01:00