Commit Graph

27 Commits

Author SHA1 Message Date
Joe Tsai dac9b9ddbd encoding: modernize Go documentation
Across all encoding packages, linkify declarations if possible.
In some cases, we convert a code block into a bulleted list,
which then further allows for more linkification.

Change-Id: I68fedf362615b34228bab5d4859b7d87d831c570
Reviewed-on: https://go-review.googlesource.com/c/go/+/524977
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: qiulaidongfeng <2645477756@qq.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2023-09-08 19:04:28 +00:00
Joe Tsai 469d9e26ee encoding: add AppendEncode and AppendDecode
Implement append-like equivalent of Encode and Decode functions.

Fixes #53693

Change-Id: I79d8d834e3c8f77fad32be2fd391e33d4d1527ea
Reviewed-on: https://go-review.googlesource.com/c/go/+/504884
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Run-TryBot: Joseph Tsai <joetsai@digital-static.net>
Auto-Submit: Joseph Tsai <joetsai@digital-static.net>
2023-08-17 16:23:42 +00:00
Joe Tsai 81eda3a339 Revert "hex: fix panic in Decode when len(src) > 2*len(dst)"
This reverts CL 461958 and CL 465855.

Reason for revert: This introduced an irreconcilable inconsistency with Encode

Fixes #58391.

Change-Id: Ifd01a04d433b24c092b73e627b8149a5851c2bca
Reviewed-on: https://go-review.googlesource.com/c/go/+/469615
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Bryan Mills <bcmills@google.com>
Run-TryBot: Joseph Tsai <joetsai@digital-static.net>
Auto-Submit: Joseph Tsai <joetsai@digital-static.net>
Reviewed-by: Ian Lance Taylor <iant@google.com>
2023-02-21 15:35:11 +00:00
Joe Tsai f02cdba163 encoding/hex: fix Decode output check regression
CL 461958 fixed a potential panic,
but also introduced an observable regression where
invalid input could be detected before the panic occurs.
Adjust the check to preserve prior behavior,
while also preventing the panic.

Change-Id: I52819f88a6a64883fbc9fd512697c38c29ca0ccd
Reviewed-on: https://go-review.googlesource.com/c/go/+/465855
Auto-Submit: Joseph Tsai <joetsai@digital-static.net>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Bryan Mills <bcmills@google.com>
Run-TryBot: Joseph Tsai <joetsai@digital-static.net>
Reviewed-by: Ian Lance Taylor <iant@google.com>
2023-02-07 15:37:55 +00:00
Benjamin Prosnitz a106defdda hex: fix panic in Decode when len(src) > 2*len(dst)
hex.Decode never checks the length of dst and triggers a panic
if there are insufficient bytes in the slice.

There isn't document on what the behavior *should* be in this case.
Two possibilities:
1. Error dst has insufficient space (as done in this change)
2. Reduce the length of the decode to min(dst, src)

Option 1 was chosen because it seems the least surprising or
subtle.

Change-Id: I3bf029e3d928202de716830434285e3c165f26dd
Reviewed-on: https://go-review.googlesource.com/c/go/+/461958
Reviewed-by: Ian Lance Taylor <iant@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
Reviewed-by: Bryan Mills <bcmills@google.com>
Run-TryBot: Ian Lance Taylor <iant@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Benjamin Prosnitz <bprosnitz@gmail.com>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
2023-01-27 15:28:30 +00:00
cuiweixie ab87db8b46 encoding: use strings.Builder
Change-Id: Ib07699df8ea41fd8d1bca8ad050859fac24623de
Reviewed-on: https://go-review.googlesource.com/c/go/+/428258
Reviewed-by: Robert Griesemer <gri@google.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Ian Lance Taylor <iant@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
2022-09-06 15:46:20 +00:00
eh-steve baf61e4a67 encoding/hex: implement Decode with a lookup table
Implement hex decode using a 256 byte lookup table instead of branching logic.

In happy flow, uses 3x 64 byte (or 5x 32 byte) cache lines.

	name             old time/op    new time/op    delta
	Decode/256-64       223ns ± 3%     135ns ± 2%  -39.64%  (p=0.000 n=8+8)
	Decode/1024-64      872ns ± 2%     512ns ± 2%  -41.25%  (p=0.000 n=8+8)
	Decode/4096-64     3.43µs ± 1%    2.01µs ± 2%  -41.31%  (p=0.001 n=7+7)
	Decode/16384-64    13.9µs ± 1%     8.0µs ± 1%  -42.69%  (p=0.000 n=8+7)

	name             old speed      new speed      delta
	Decode/256-64    1.15GB/s ± 3%  1.90GB/s ± 2%  +65.66%  (p=0.000 n=8+8)
	Decode/1024-64   1.17GB/s ± 2%  2.00GB/s ± 2%  +70.22%  (p=0.000 n=8+8)
	Decode/4096-64   1.20GB/s ± 1%  2.04GB/s ± 2%  +70.39%  (p=0.001 n=7+7)
	Decode/16384-64  1.18GB/s ± 1%  2.06GB/s ± 1%  +74.49%  (p=0.000 n=8+7)

Also reduces amd64 object size by 766 bytes, despite the extra RODATA due to removal of `fromHexChar()` and duplicated inlined versions of it and simplification of `Decode()`.

Change-Id: I0988c7a30562ec154eff11db6e27954e0ce2b611
GitHub-Last-Rev: 64818018af
GitHub-Pull-Request: golang/go#51432
Reviewed-on: https://go-review.googlesource.com/c/go/+/390037
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
Trust: Daniel Martí <mvdan@mvdan.cc>
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gopher Robot <gobot@golang.org>
2022-03-11 21:51:20 +00:00
Russ Cox 1b09d43067 all: update references to symbols moved from io/ioutil to io
The old ioutil references are still valid, but update our code
to reflect best practices and get used to the new locations.

Code compiled with the bootstrap toolchain
(cmd/asm, cmd/dist, cmd/compile, debug/elf)
must remain Go 1.4-compatible and is excluded.
Also excluded vendored code.

For #41190.

Change-Id: I6d86f2bf7bc37a9d904b6cee3fe0c7af6d94d5b1
Reviewed-on: https://go-review.googlesource.com/c/go/+/263142
Trust: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>
2020-10-20 18:41:18 +00:00
Tim Cooper 96acb74655 encoding/hex: remove unused variable from BenchmarkDump
Change-Id: I1fd47e5eab27346cec488098d4f6102a0749bd28
Reviewed-on: https://go-review.googlesource.com/c/go/+/221788
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2020-03-03 14:53:52 +00:00
Daniel Martí a563f2f417 encoding/hex: simplify encoder arithmetic
Two additions are faster than two multiplications and one addition. The
code seems simpler to me too, as it's more obvious that we advance two
destination bytes for each source byte.

name            old time/op  new time/op  delta
Encode/256-8     374ns ± 0%   331ns ± 0%  -11.44%  (p=0.008 n=5+5)
Encode/1024-8   1.47µs ± 0%  1.29µs ± 0%  -11.89%  (p=0.004 n=6+5)
Encode/4096-8   5.85µs ± 1%  5.15µs ± 0%  -11.89%  (p=0.004 n=6+5)
Encode/16384-8  23.3µs ± 0%  20.6µs ± 0%  -11.68%  (p=0.004 n=6+5)

Change-Id: Iabc63616c1d9fded55fa668ff41dd49efeaa2ea4
Reviewed-on: https://go-review.googlesource.com/c/go/+/151198
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: roger peppe <rogpeppe@gmail.com>
2019-03-05 17:40:09 +00:00
Daniel Martí aa5165d62c encoding/hex: simplify decoder arithmetic
Remove all multiplications and divisions from the main decoding loop.

name            old time/op   new time/op   delta
Decode/256-8      323ns ± 0%    293ns ± 0%   -9.29%  (p=0.000 n=5+4)
Decode/1024-8    1.26µs ± 0%   1.14µs ± 0%   -9.48%  (p=0.000 n=6+5)
Decode/4096-8    4.99µs ± 0%   4.51µs ± 0%   -9.55%  (p=0.002 n=6+6)
Decode/16384-8   20.0µs ± 0%   18.1µs ± 0%   -9.54%  (p=0.002 n=6+6)

name            old speed     new speed     delta
Decode/256-8    791MB/s ± 0%  872MB/s ± 0%  +10.34%  (p=0.002 n=6+6)
Decode/1024-8   814MB/s ± 0%  899MB/s ± 0%  +10.48%  (p=0.004 n=6+5)
Decode/4096-8   821MB/s ± 0%  908MB/s ± 0%  +10.55%  (p=0.002 n=6+6)
Decode/16384-8  821MB/s ± 0%  908MB/s ± 0%  +10.54%  (p=0.002 n=6+6)

Change-Id: Ie9f91242ce04c130a77c1184379e3b9de38fe713
Reviewed-on: https://go-review.googlesource.com/c/151199
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2019-03-02 16:48:05 +00:00
Tim Cooper 352583ff77 encoding/hex: pre-allocate Dump buffer
name          old time/op    new time/op    delta
Dump/256-4      7.76µs ± 2%    5.82µs ± 2%  -24.91%  (p=0.008 n=5+5)
Dump/1024-4     28.4µs ± 2%    22.6µs ± 3%  -20.58%  (p=0.008 n=5+5)
Dump/4096-4      112µs ± 2%      88µs ± 0%  -20.80%  (p=0.016 n=5+4)
Dump/16384-4     444µs ± 3%     361µs ± 7%  -18.73%  (p=0.008 n=5+5)

name          old alloc/op   new alloc/op   delta
Dump/256-4      4.00kB ± 0%    1.39kB ± 0%  -65.20%  (p=0.008 n=5+5)
Dump/1024-4     16.2kB ± 0%     5.5kB ± 0%  -66.04%  (p=0.008 n=5+5)
Dump/4096-4     63.9kB ± 0%    20.6kB ± 0%  -67.78%  (p=0.008 n=5+5)
Dump/16384-4     265kB ± 0%      82kB ± 0%  -69.00%  (p=0.008 n=5+5)

name          old allocs/op  new allocs/op  delta
Dump/256-4        7.00 ± 0%      3.00 ± 0%  -57.14%  (p=0.008 n=5+5)
Dump/1024-4       9.00 ± 0%      3.00 ± 0%  -66.67%  (p=0.008 n=5+5)
Dump/4096-4       11.0 ± 0%       3.0 ± 0%  -72.73%  (p=0.008 n=5+5)
Dump/16384-4      13.0 ± 0%       3.0 ± 0%  -76.92%  (p=0.008 n=5+5)

Change-Id: I0a0d6de315b979142b05e333880da8a5e52b12ef
Reviewed-on: https://go-review.googlesource.com/116495
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-08-21 02:10:52 +00:00
Josh Bleecher Snyder a34e6650c0 encoding/hex: improve Decode and DecodeString docs
Simplify the wording of both.

Make the DecodeString docs more accurate:
DecodeString returns a slice, not a string.

Change-Id: Iba7003f55fb0a37aafcbeee59a30492c0f68aa4e
Reviewed-on: https://go-review.googlesource.com/115615
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2018-05-31 19:49:01 +00:00
Tim Cooper 9db1dd074d encoding/hex: fix Dumper not always closing on Close call
Updates #23574

Change-Id: I1b87390679e0817a2f6e4e5938994ea32df87bd7
Reviewed-on: https://go-review.googlesource.com/107596
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-04-17 20:14:55 +00:00
Tim Cooper 0519126a3f encoding/hex: fix potential incorrect Dumper output when Close is called multiple times
Fixes #23574

Change-Id: I69573de47daa6fd53cc99a78c0c4b867460242e3
Reviewed-on: https://go-review.googlesource.com/90275
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
2018-02-14 03:25:25 +00:00
Russ Cox d0ce197c58 encoding/hex: make Decode, Decoder, DecodeString agree about partial results and errors
CL 70210 added Decoder for #21590, and in doing so it changed
the existing func Decode to return partial results for decoding errors.
That seems like a good change to make to Decode, but it was
untested (except as used by Decoder), inconsistent with DecodeString
in all error cases, and inconsistent with Decoder in not returning
partial results for odd-length input strings.

This CL makes Decode, DecodeString, and Decoder all agree about
the handling of partial results (they are returned) and error
precedence (the error earliest in the input is reported),
and it documents and tests this.

Change-Id: Ifb7d1e100ecb66fe2ed5ba34a621084d480f16db
Reviewed-on: https://go-review.googlesource.com/78120
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-11-16 01:08:20 +00:00
Tim Cooper 6db4950dc5 encoding/hex: add NewEncoder, NewDecoder
NewEncoder returns an io.Writer that writes all incoming bytes as
hexadecimal characters to the underlying io.Writer. NewDecoder returns an
io.Reader that does the inverse.

Fixes #21590

Change-Id: Iebe0813faf365b42598f19a9aa41768f571dc0a8
Reviewed-on: https://go-review.googlesource.com/70210
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-20 23:47:07 +00:00
Agniva De Sarker 22cfe24aca encoding/hex: save allocation in DecodeString()
The destination slice does not need to be created at all. The source
slice itself can be used as the destination because the decode loop
increments by one and then the 'seen' byte is not used anymore. Therefore
the decoded byte can be stored in that index of the source slice itself.

This trick cannot be applied to EncodeString() because in that case,
the destination slice is large than the source. And for a single byte
in the source slice, two bytes in the destination slice is written.

func BenchmarkDecodeString(b *testing.B) {
  for i := 0; i < b.N; i++ {
    DecodeString("0123456789abcdef")
  }
}

name          old time/op    new time/op    delta
DecodeString    71.0ns ± 6%    58.0ns ± 0%  -18.28%  (p=0.008 n=5+5)

name          old alloc/op   new alloc/op   delta
DecodeString     16.0B ± 0%      8.0B ± 0%  -50.00%  (p=0.008 n=5+5)

name          old allocs/op  new allocs/op  delta
DecodeString      1.00 ± 0%      1.00 ± 0%     ~     (all equal)

Change-Id: Id98db4e712444557a804155457a4dd8d1b8b416d
Reviewed-on: https://go-review.googlesource.com/55611
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-08-15 14:35:34 +00:00
Agniva De Sarker 98276d6abe encoding/hex: improve tests
The tests for error scenarios were done by manually checking
error strings. Improved them by checking the actual error type
instead of just the string.

Printing the actual error in case of failure instead of a
generic string.

Also added a new scenario with both an invalid byte and an
invalid length string to verify that the length is checked first
before doing any computation.

Change-Id: Ic2a19a6d6058912632d597590186ee2d8348cb45
Reviewed-on: https://go-review.googlesource.com/55256
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-08-14 04:45:52 +00:00
Josh Bleecher Snyder 5e15497b56 encoding/hex: change lookup table back to string
CL 27254 changed hextable to a byte array for performance.
CL 28219 fixed the compiler so that that is no longer necessary.
As Kirill notes in #15808, a string is preferable
as the linker can easily de-dup it.
So go back. No performance changes.

Change-Id: Ibef7d21d0f2507968a0606602c5dd57ed4a85b1b
Reviewed-on: https://go-review.googlesource.com/40970
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-04-18 18:16:08 +00:00
Thordur Bjornsson afa68b36cc encoding/hex: Document DecodedLen.
Mention that it specifically returns x / 2, and do the same for
EncodedLen.

Change-Id: Ie334f5abecbc487caf4965abbcd14442591bef2a
Change-Id: Idfa413faad487e534489428451bf736b009293d6
Reviewed-on: https://go-review.googlesource.com/33191
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-11-13 17:53:22 +00:00
Josh Bleecher Snyder 4cf95fda64 encoding/hex: fix example function name
Found by vet.

Change-Id: I556d87f853a734002f779b04ba5a3588a3117106
Reviewed-on: https://go-review.googlesource.com/28958
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-09-10 21:40:16 +00:00
Emmanuel Odeke 141f1a0e24 encoding/hex: implement examples using all exported functions
Fixes #11254.
Updates #16360.

Implements examples using all exported functions.

This CL also updates Decode documentation to
state that only hexadecimal characters are accepted
in the source slice src, but also that the length
of src must be even.

Change-Id: Id016a4ba814f940cd300f26581fb4b9d2aded306
Reviewed-on: https://go-review.googlesource.com/28482
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
2016-09-08 19:51:01 +00:00
Alberto Donizetti 57370a87d8 encoding/hex: change lookup table from string to array
name            old time/op  new time/op  delta
Encode/256-4     431ns ± 2%   391ns ± 2%   -9.36%  (p=0.000 n=8+8)
Encode/1024-4   1.68µs ± 0%  1.51µs ± 0%   -9.91%  (p=0.001 n=7+7)
Encode/4096-4   6.68µs ± 0%  6.03µs ± 1%   -9.69%  (p=0.000 n=8+8)
Encode/16384-4  27.0µs ± 1%  24.0µs ± 0%  -11.03%  (p=0.000 n=8+7)

Change-Id: I6994e02f77797349c4e188377d84f97dffe98399
Reviewed-on: https://go-review.googlesource.com/27254
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-08-17 23:35:32 +00:00
Brad Fitzpatrick 5fea2ccc77 all: single space after period.
The tree's pretty inconsistent about single space vs double space
after a period in documentation. Make it consistently a single space,
per earlier decisions. This means contributors won't be confused by
misleading precedence.

This CL doesn't use go/doc to parse. It only addresses // comments.
It was generated with:

$ perl -i -npe 's,^(\s*// .+[a-z]\.)  +([A-Z]),$1 $2,' $(git grep -l -E '^\s*//(.+\.)  +([A-Z])')
$ go test go/doc -update

Change-Id: Iccdb99c37c797ef1f804a94b22ba5ee4b500c4f7
Reviewed-on: https://go-review.googlesource.com/20022
Reviewed-by: Rob Pike <r@golang.org>
Reviewed-by: Dave Day <djd@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-03-02 00:13:47 +00:00
Josh Bleecher Snyder 1dbba1a2b7 encoding/hex: minor cleanup
Change-Id: I404fd946dd0607fa41e2abe0d1d8081d4433ff0a
Reviewed-on: https://go-review.googlesource.com/19762
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-02-21 03:59:22 +00:00
Russ Cox c007ce824d build: move package sources from src/pkg to src
Preparation was in CL 134570043.
This CL contains only the effect of 'hg mv src/pkg/* src'.
For more about the move, see golang.org/s/go14nopkg.
2014-09-08 00:08:51 -04:00