Add a simple IRC notifier utility

2 files changed, 132 insertions, 126 deletions

diff --git a/xS/irc.go b/xS/irc.go
new file mode 100644
index 0000000..71bf961
--- /dev/null
+++ b/xS/irc.go
@@ -0,0 +1,132 @@
+package main
+
+import (
+	"path/filepath"
+	"regexp"
+	"strings"
+)
+
+func ircToLower(c byte) byte {
+	switch c {
+	case '[':
+		return '{'
+	case ']':
+		return '}'
+	case '\\':
+		return '|'
+	case '~':
+		return '^'
+	}
+	if c >= 'A' && c <= 'Z' {
+		return c + ('a' - 'A')
+	}
+	return c
+}
+
+func ircToUpper(c byte) byte {
+	switch c {
+	case '{':
+		return '['
+	case '}':
+		return ']'
+	case '|':
+		return '\\'
+	case '^':
+		return '~'
+	}
+	if c >= 'a' && c <= 'z' {
+		return c - ('a' - 'A')
+	}
+	return c
+}
+
+// Convert identifier to a canonical form for case-insensitive comparisons.
+// ircToUpper is used so that statically initialized maps can be in uppercase.
+func ircToCanon(ident string) string {
+	var canon []byte
+	for _, c := range []byte(ident) {
+		canon = append(canon, ircToUpper(c))
+	}
+	return string(canon)
+}
+
+func ircEqual(s1, s2 string) bool {
+	return ircToCanon(s1) == ircToCanon(s2)
+}
+
+func ircFnmatch(pattern string, s string) bool {
+	pattern, s = ircToCanon(pattern), ircToCanon(s)
+	// FIXME: This should not support [] ranges and handle '/' specially.
+	// We could translate the pattern to a regular expression.
+	matched, _ := filepath.Match(pattern, s)
+	return matched
+}
+
+var reMsg = regexp.MustCompile(
+	`^(?:@([^ ]*) +)?(?::([^! ]*)(?:!([^@]*)@([^ ]*))? +)?([^ ]+)(.*)?$`)
+var reArgs = regexp.MustCompile(`:.*| [^: ][^ ]*`)
+
+type message struct {
+	tags    map[string]string // IRC 3.2 message tags
+	nick    string            // optional nickname
+	user    string            // optional username
+	host    string            // optional hostname or IP address
+	command string            // command name
+	params  []string          // arguments
+}
+
+func ircUnescapeMessageTag(value string) string {
+	var buf []byte
+	escape := false
+	for i := 0; i < len(value); i++ {
+		if escape {
+			switch value[i] {
+			case ':':
+				buf = append(buf, ';')
+			case 's':
+				buf = append(buf, ' ')
+			case 'r':
+				buf = append(buf, '\r')
+			case 'n':
+				buf = append(buf, '\n')
+			default:
+				buf = append(buf, value[i])
+			}
+			escape = false
+		} else if value[i] == '\\' {
+			escape = true
+		} else {
+			buf = append(buf, value[i])
+		}
+	}
+	return string(buf)
+}
+
+func ircParseMessageTags(tags string, out map[string]string) {
+	for _, tag := range strings.Split(tags, ";") {
+		if tag == "" {
+			// Ignore empty.
+		} else if equal := strings.IndexByte(tag, '='); equal < 0 {
+			out[tag] = ""
+		} else {
+			out[tag[:equal]] = ircUnescapeMessageTag(tag[equal+1:])
+		}
+	}
+}
+
+func ircParseMessage(line string) *message {
+	m := reMsg.FindStringSubmatch(line)
+	if m == nil {
+		return nil
+	}
+
+	msg := message{nil, m[2], m[3], m[4], m[5], nil}
+	if m[1] != "" {
+		msg.tags = make(map[string]string)
+		ircParseMessageTags(m[1], msg.tags)
+	}
+	for _, x := range reArgs.FindAllString(m[6], -1) {
+		msg.params = append(msg.params, x[1:])
+	}
+	return &msg
+}
diff --git a/xS/xS.go b/xS/xS.go
index 25db005..69a9b36 100644
--- a/xS/xS.go
+++ b/xS/xS.go
@@ -456,132 +456,6 @@ func (fd *floodDetector) check() bool {
 	return count <= fd.limit
 }
 
-// --- IRC protocol ------------------------------------------------------------
-
-func ircToLower(c byte) byte {
-	switch c {
-	case '[':
-		return '{'
-	case ']':
-		return '}'
-	case '\\':
-		return '|'
-	case '~':
-		return '^'
-	}
-	if c >= 'A' && c <= 'Z' {
-		return c + ('a' - 'A')
-	}
-	return c
-}
-
-func ircToUpper(c byte) byte {
-	switch c {
-	case '{':
-		return '['
-	case '}':
-		return ']'
-	case '|':
-		return '\\'
-	case '^':
-		return '~'
-	}
-	if c >= 'a' && c <= 'z' {
-		return c - ('a' - 'A')
-	}
-	return c
-}
-
-// Convert identifier to a canonical form for case-insensitive comparisons.
-// ircToUpper is used so that statically initialized maps can be in uppercase.
-func ircToCanon(ident string) string {
-	var canon []byte
-	for _, c := range []byte(ident) {
-		canon = append(canon, ircToUpper(c))
-	}
-	return string(canon)
-}
-
-func ircEqual(s1, s2 string) bool {
-	return ircToCanon(s1) == ircToCanon(s2)
-}
-
-func ircFnmatch(pattern string, s string) bool {
-	pattern, s = ircToCanon(pattern), ircToCanon(s)
-	// FIXME: This should not support [] ranges and handle '/' specially.
-	// We could translate the pattern to a regular expression.
-	matched, _ := filepath.Match(pattern, s)
-	return matched
-}
-
-var reMsg = regexp.MustCompile(
-	`^(?:@([^ ]*) +)?(?::([^! ]*)(?:!([^@]*)@([^ ]*))? +)?([^ ]+)(.*)?$`)
-var reArgs = regexp.MustCompile(`:.*| [^: ][^ ]*`)
-
-type message struct {
-	tags    map[string]string // IRC 3.2 message tags
-	nick    string            // optional nickname
-	user    string            // optional username
-	host    string            // optional hostname or IP address
-	command string            // command name
-	params  []string          // arguments
-}
-
-func ircUnescapeMessageTag(value string) string {
-	var buf []byte
-	escape := false
-	for i := 0; i < len(value); i++ {
-		if escape {
-			switch value[i] {
-			case ':':
-				buf = append(buf, ';')
-			case 's':
-				buf = append(buf, ' ')
-			case 'r':
-				buf = append(buf, '\r')
-			case 'n':
-				buf = append(buf, '\n')
-			default:
-				buf = append(buf, value[i])
-			}
-			escape = false
-		} else if value[i] == '\\' {
-			escape = true
-		} else {
-			buf = append(buf, value[i])
-		}
-	}
-	return string(buf)
-}
-
-func ircParseMessageTags(tags string, out map[string]string) {
-	for _, tag := range splitString(tags, ";", true /* ignoreEmpty */) {
-		if equal := strings.IndexByte(tag, '='); equal < 0 {
-			out[tag] = ""
-		} else {
-			out[tag[:equal]] = ircUnescapeMessageTag(tag[equal+1:])
-		}
-	}
-}
-
-func ircParseMessage(line string) *message {
-	m := reMsg.FindStringSubmatch(line)
-	if m == nil {
-		return nil
-	}
-
-	msg := message{nil, m[2], m[3], m[4], m[5], nil}
-	if m[1] != "" {
-		msg.tags = make(map[string]string)
-		ircParseMessageTags(m[1], msg.tags)
-	}
-	for _, x := range reArgs.FindAllString(m[6], -1) {
-		msg.params = append(msg.params, x[1:])
-	}
-	return &msg
-
-}
-
 // --- IRC token validation ----------------------------------------------------
 
 // Everything as per RFC 2812