1
0
mirror of https://github.com/golang/go synced 2024-11-18 16:04:44 -07:00
The Go programming language
Go to file
Didier Spezia f4e3e5eaf0 html/template: fix quadratic performance with special tags
The current implementation of the tSpecialTagEnd function
is inefficient since it generates plenty of memory allocations
and converts the whole buffer to lowercase at each call.

If the number of special tags increases linearly with the
template size, the complexity becomes quadratic.

This CL provides an alternative implementation.
While the algorithm is probably still not optimal, it avoids
the quadratic behavior and the memory allocations.

benchmark                          old ns/op     new ns/op     delta
BenchmarkTemplateSpecialTags-4     19326431      532190        -97.25%

benchmark                          old allocs    new allocs    delta
BenchmarkTemplateSpecialTags-4     2650          190           -92.83%

benchmark                          old bytes     new bytes     delta
BenchmarkTemplateSpecialTags-4     4106460       46568         -98.87%

While we are there, make sure we respect the HTML tokenization algorithm.
An end tag needs to be followed by a space, tab, CR, FF, /, or > as described
in https://html.spec.whatwg.org/multipage/syntax.html#tokenization
Explicitly add this check.

Fixes #10605

Change-Id: Ia33ddee164ab608a69ac4183e16ec506bbeaa54c
Reviewed-on: https://go-review.googlesource.com/9502
Reviewed-by: Rob Pike <r@golang.org>
2015-04-30 16:22:29 +00:00
api api: update next.txt 2015-04-11 07:13:48 +00:00
doc doc/go1.5.txt: add Jacobi and Int.ModSqrt to math/big 2015-04-30 15:35:19 +00:00
lib/time remove the obsolete lib/codereview. 2014-12-08 07:51:54 +00:00
misc misc/cgo/testshared: add basic test for -buildmode=shared/-linkshared 2015-04-29 23:47:47 +00:00
src html/template: fix quadratic performance with special tags 2015-04-30 16:22:29 +00:00
test test: gofmt run.go 2015-04-28 00:08:50 +00:00
.gitattributes .gitattributes: prevent all magic line ending changes 2014-12-12 23:14:54 +00:00
.gitignore .gitignore: ignore ARM64 build products 2015-03-16 18:44:22 +00:00
AUTHORS A+C: add another email address for Emil Hessman 2014-11-12 10:01:23 -08:00
CONTRIBUTING.md doc: direct people to the mailing list 2015-01-18 21:27:07 +00:00
CONTRIBUTORS C: add Nick Cooper (Google CLA). 2014-11-14 17:03:17 +11:00
favicon.ico
LICENSE
PATENTS
README.md doc: fix broken link in README 2015-02-19 05:50:57 +00:00
robots.txt

The Go Programming Language

Go is an open source programming language that makes it easy to build simple, reliable, and efficient software.

Gopher image

For documentation about how to install and use Go, visit https://golang.org/ or load doc/install-source.html in your web browser.

Our canonical Git repository is located at https://go.googlesource.com/go. There is a mirror of the repository at https://github.com/golang/go.

Please report issues here: https://golang.org/issue/new

Go is the work of hundreds of contributors. We appreciate your help!

To contribute, please read the contribution guidelines: https://golang.org/doc/contribute.html

Please note that we do not use pull requests.

Unless otherwise noted, the Go source files are distributed under the BSD-style license found in the LICENSE file.

--

Binary Distribution Notes

If you have just untarred a binary Go distribution, you need to set the environment variable $GOROOT to the full path of the go directory (the one containing this file). You can omit the variable if you unpack it into /usr/local/go, or if you rebuild from sources by running all.bash (see doc/install-source.html). You should also add the Go binary directory $GOROOT/bin to your shell's path.

For example, if you extracted the tar file into $HOME/go, you might put the following in your .profile:

export GOROOT=$HOME/go
export PATH=$PATH:$GOROOT/bin

See https://golang.org/doc/install or doc/install.html for more details.