Commit Graph

19 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 a93f3e4f6b
copyHeader is redundant (#672)
copyHeader() is redundant, we allocate a header and then copy the
non-pointer elements into it; we don't need to do this, because if we
just asssign rr.Hdr to something else we get the same result.

Remove copyHeader() and the generation and use of it in ztypes.go.
2018-05-10 14:50:26 +01:00
Miek Gieben 6ae3b9f061 Skip reflection for most types (#369)
Make the reflection types a black list (these types use (or should use)
the tag 'size-xxx' in their struct definition.s

HIP, IPSECKEY, NSEC3, TSIG

All other types don't use reflection anymore.

* Return a pointer to the header when there is no rdata, this restores old
  behavior. The rest of the conversion mostly hangs on getting size-hex
  right, but then packStruct and packStructValue and the unpack variant
  can be killed.
* Generate pack and unpack for all embedded types as well.
* Fix PrivateRRs, register an unpack function as well, when you register
  a new PrivateRR.
* Add the tag octet, nsec, []domains and more  to msg_helper.go
2016-06-12 16:09:37 +01:00
Miek Gieben 907a4aef57 Generate pack/unpack for all RRs (#360)
Add dns:txt parsing helper to prevent compile errors. This allows
us to generate all unpack/pack function.

Add pack to the RR interface definition and add this method to
PrivateRR.

We still use typeToUnpack to select which types don't use reflection.
2016-06-05 07:53:12 +01:00
Filippo Valsorda 023972bb19 Expose TypeToRR 2015-10-16 23:36:49 +01:00
Miek Gieben 79547a0341 Add Dedup function
Add function that dedups a list of RRs. Work on strings, which
adds garbage, but seems to be the least intrusive and takes the
last amount of memory.

Some fmt changes snook in as well.
2015-08-24 22:02:57 +01:00
Miek Gieben 9bf52083d1 golint fixes 2015-08-23 08:03:13 +01:00
Miek Gieben 64fea017a2 Move all docs to docs.go
Another golint change.
2015-02-19 13:47:50 +00:00
Miek Gieben b02ae55fbe golint changes, lose the underscores 2015-02-19 10:45:59 +00:00
Alex Sergeyev aaf867499e Attempting to fix #133
- Trying to get as close to original state as possible
- Since private RR should not run slurp, toggling Variable there.
2014-09-23 21:59:09 -04:00
Miek Gieben 45e66bfe1d Rename ParseTextSlice to Parse.
Shorter.
2014-09-21 19:09:13 +01:00
Miek Gieben 45f3dc89e4 Rename CopyRdata to just Copy.
Still not sure if this makes things more clear.
2014-09-21 18:30:16 +01:00
Miek Gieben 685f708a9e Rename RdataLen to just Len 2014-09-21 18:21:34 +01:00
Miek Gieben 6ee673464d Small doc update 2014-09-21 09:09:50 +01:00
Miek Gieben 9c9f3646ff More naming and some docs 2014-09-21 09:07:26 +01:00
Miek Gieben b90da23741 Fix tests and examples.
Put all examples in the same file and cleanup the tests to use
the new names.
2014-09-21 08:38:17 +01:00
Miek Gieben 9c455b0214 PrivateRR: naming naming naming
Try to find better (=more in sync with the rest of the lib) naming. My
guess is that these are better, but YMMV.
2014-09-21 08:28:38 +01:00
Miek Gieben 7e792338bb Move custom* filenames to private to be in sync with the type 2014-09-21 07:56:01 +01:00