First commit

vendor/github.com/tdewolff/parse/xml/util.go

@@ -0,0 +1,108 @@
+package xml // import "github.com/tdewolff/parse/xml"
+
+import "github.com/tdewolff/parse"
+
+var (
+	ltEntityBytes          = []byte("<")
+	ampEntityBytes         = []byte("&")
+	singleQuoteEntityBytes = []byte("'")
+	doubleQuoteEntityBytes = []byte(""")
+)
+
+// EscapeAttrVal returns the escape attribute value bytes without quotes.
+func EscapeAttrVal(buf *[]byte, b []byte) []byte {
+	singles := 0
+	doubles := 0
+	for i, c := range b {
+		if c == '&' {
+			if quote, n := parse.QuoteEntity(b[i:]); n > 0 {
+				if quote == '"' {
+					doubles++
+				} else {
+					singles++
+				}
+			}
+		} else if c == '"' {
+			doubles++
+		} else if c == '\'' {
+			singles++
+		}
+	}
+
+	n := len(b) + 2
+	var quote byte
+	var escapedQuote []byte
+	if doubles > singles {
+		n += singles * 4
+		quote = '\''
+		escapedQuote = singleQuoteEntityBytes
+	} else {
+		n += doubles * 4
+		quote = '"'
+		escapedQuote = doubleQuoteEntityBytes
+	}
+	if n > cap(*buf) {
+		*buf = make([]byte, 0, n) // maximum size, not actual size
+	}
+	t := (*buf)[:n] // maximum size, not actual size
+	t[0] = quote
+	j := 1
+	start := 0
+	for i, c := range b {
+		if c == '&' {
+			if entityQuote, n := parse.QuoteEntity(b[i:]); n > 0 {
+				j += copy(t[j:], b[start:i])
+				if entityQuote != quote {
+					t[j] = entityQuote
+					j++
+				} else {
+					j += copy(t[j:], escapedQuote)
+				}
+				start = i + n
+			}
+		} else if c == quote {
+			j += copy(t[j:], b[start:i])
+			j += copy(t[j:], escapedQuote)
+			start = i + 1
+		}
+	}
+	j += copy(t[j:], b[start:])
+	t[j] = quote
+	return t[:j+1]
+}
+
+// EscapeCDATAVal returns the escaped text bytes.
+func EscapeCDATAVal(buf *[]byte, b []byte) ([]byte, bool) {
+	n := 0
+	for _, c := range b {
+		if c == '<' || c == '&' {
+			if c == '<' {
+				n += 3 // &lt;
+			} else {
+				n += 4 // &amp;
+			}
+			if n > len("<![CDATA[]]>") {
+				return b, false
+			}
+		}
+	}
+	if len(b)+n > cap(*buf) {
+		*buf = make([]byte, 0, len(b)+n)
+	}
+	t := (*buf)[:len(b)+n]
+	j := 0
+	start := 0
+	for i, c := range b {
+		if c == '<' {
+			j += copy(t[j:], b[start:i])
+			j += copy(t[j:], ltEntityBytes)
+			start = i + 1
+		} else if c == '&' {
+			j += copy(t[j:], b[start:i])
+			j += copy(t[j:], ampEntityBytes)
+			start = i + 1
+		}
+	}
+	j += copy(t[j:], b[start:])
+	return t[:j], true
+}