1 files changed, 0 insertions, 113 deletions
diff --git a/tags.go b/tags.go
deleted file mode 100644
index 9fb95f5..0000000
--- a/tags.go
+++ /dev/null
@@ -1,113 +0,0 @@
-// Almost everything in this file is adapted from Ergo IRCd
-// This is probably considered a derived work for copyright purposes
-
-package main
-
-import (
-	"strings"
-	"unicode/utf8"
-)
-
-func parseTags(tagsString string) (tags map[string]string, err error) {
-	tags = make(map[string]string)
-	for 0 < len(tagsString) {
-		tagEnd := strings.IndexByte(tagsString, ';')
-		endPos := tagEnd
-		nextPos := tagEnd + 1
-		if tagEnd == -1 {
-			endPos = len(tagsString)
-			nextPos = len(tagsString)
-		}
-		tagPair := tagsString[:endPos]
-		equalsIndex := strings.IndexByte(tagPair, '=')
-		var tagName, tagValue string
-		if equalsIndex == -1 {
-			// Tag with no value
-			tagName = tagPair
-		} else {
-			tagName, tagValue = tagPair[:equalsIndex], tagPair[equalsIndex+1:]
-		}
-		// "Implementations [...] MUST NOT perform any validation that would
-		//  reject the message if an invalid tag key name is used."
-		if validateTagName(tagName) {
-			// "Tag values MUST be encoded as UTF8."
-			if !utf8.ValidString(tagValue) {
-				err = ErrInvalidTagContent
-				return
-			}
-			tags[tagName] = UnescapeTagValue(tagValue)
-		}
-		tagsString = tagsString[nextPos:]
-	}
-	return
-}
-
-func UnescapeTagValue(inString string) string {
-	// buf.Len() == 0 is the fastpath where we have not needed to unescape any chars
-	var buf strings.Builder
-	remainder := inString
-	for {
-		backslashPos := strings.IndexByte(remainder, '\\')
-
-		if backslashPos == -1 {
-			if buf.Len() == 0 {
-				return inString
-			} else {
-				buf.WriteString(remainder)
-				break
-			}
-		} else if backslashPos == len(remainder)-1 {
-			// trailing backslash, which we strip
-			if buf.Len() == 0 {
-				return inString[:len(inString)-1]
-			} else {
-				buf.WriteString(remainder[:len(remainder)-1])
-				break
-			}
-		}
-
-		// Non-trailing backslash detected; we're now on the slowpath
-		// where we modify the string
-		if buf.Len() < len(inString) {
-			buf.Grow(len(inString))
-		}
-		buf.WriteString(remainder[:backslashPos])
-		buf.WriteByte(escapedCharLookupTable[remainder[backslashPos+1]])
-		remainder = remainder[backslashPos+2:]
-	}
-
-	return buf.String()
-}
-
-var escapedCharLookupTable [256]byte
-
-func init() {
-	for i := 0; i < 256; i += 1 {
-		escapedCharLookupTable[i] = byte(i)
-	}
-	escapedCharLookupTable[':'] = ';'
-	escapedCharLookupTable['s'] = ' '
-	escapedCharLookupTable['r'] = '\r'
-	escapedCharLookupTable['n'] = '\n'
-}
-
-// https://ircv3.net/specs/extensions/message-tags.html#rules-for-naming-message-tags
-func validateTagName(name string) bool {
-	if len(name) == 0 {
-		return false
-	}
-	if name[0] == '+' {
-		name = name[1:]
-	}
-	if len(name) == 0 {
-		return false
-	}
-	// Let's err on the side of leniency here; allow -./ (45-47) in any position
-	for i := 0; i < len(name); i++ {
-		c := name[i]
-		if !(('-' <= c && c <= '/') || ('0' <= c && c <= '9') || ('A' <= c && c <= 'Z') || ('a' <= c && c <= 'z')) {
-			return false
-		}
-	}
-	return true
-}