43 lines
1 KiB
Go
43 lines
1 KiB
Go
|
// Copyright (c) 2016 Tomas Aparicio. All rights reserved.
|
||
|
|
//
|
||
|
|
// Use of this source code is governed by a MIT License
|
||
|
|
// license that can be found in the LICENSE file or at
|
||
|
|
// https://github.com/h2non/go-is-svg/blob/master/LICENSE.
|
||
|
|
|
||
|
|
package svg
|
||
|
|
|
||
|
|
import (
|
||
|
|
"regexp"
|
||
|
|
"unicode/utf8"
|
||
|
|
)
|
||
|
|
|
||
|
|
var (
|
||
|
|
htmlCommentRegex = regexp.MustCompile(`(?i)<!--([\s\S]*?)-->`)
|
||
|
|
svgRegex = regexp.MustCompile(`(?i)^\s*(?:<\?xml[^>]*>\s*)?(?:<!doctype svg[^>]*>\s*)?<svg[^>]*>`)
|
||
|
|
)
|
||
|
|
|
||
|
|
// isBinary checks if the given buffer is a binary file.
|
||
|
|
func isBinary(buf []byte) bool {
|
||
|
|
if len(buf) < 24 {
|
||
|
|
return false
|
||
|
|
}
|
||
|
|
for i := 0; i < 24; i++ {
|
||
|
|
charCode, _ := utf8.DecodeRuneInString(string(buf[i]))
|
||
|
|
if charCode == 65533 || charCode <= 8 {
|
||
|
|
return true
|
||
|
|
}
|
||
|
|
}
|
||
|
|
return false
|
||
|
|
}
|
||
|
|
|
||
|
|
// Is returns true if the given buffer is a valid SVG image.
|
||
|
|
func Is(buf []byte) bool {
|
||
|
|
return !isBinary(buf) && svgRegex.Match(htmlCommentRegex.ReplaceAll(buf, []byte{}))
|
||
|
|
}
|
||
|
|
|
||
|
|
// IsSVG returns true if the given buffer is a valid SVG image.
|
||
|
|
// Alias to: Is()
|
||
|
|
func IsSVG(buf []byte) bool {
|
||
|
|
return Is(buf)
|
||
|
|
}
|