app-init

internal/navicat/binary.go

@@ -0,0 +1,76 @@
+package navicat
+
+import (
+	"encoding/binary"
+	"fmt"
+)
+
+func putU32(n uint32) []byte {
+	b := make([]byte, 4)
+	binary.BigEndian.PutUint32(b, n)
+	return b
+}
+
+func putU16(n uint16) []byte {
+	b := make([]byte, 2)
+	binary.BigEndian.PutUint16(b, n)
+	return b
+}
+
+// AppendBlock encodes GetBlock() from ntunnel_mysql.php.
+// NULL is not represented here; use AppendNull for row cells.
+func AppendBlock(dst []byte, val []byte) []byte {
+	if val == nil {
+		val = []byte{}
+	}
+	n := len(val)
+	if n < 254 {
+		dst = append(dst, byte(n))
+		return append(dst, val...)
+	}
+	dst = append(dst, markLong)
+	dst = append(dst, putU32(uint32(n))...)
+	return append(dst, val...)
+}
+
+func AppendNull(dst []byte) []byte {
+	return append(dst, markNull)
+}
+
+func AppendHeader(dst []byte, version uint16, errno uint32) []byte {
+	dst = append(dst, putU32(Magic)...)
+	dst = append(dst, putU16(version)...)
+	dst = append(dst, putU32(errno)...)
+	dst = append(dst, 0, 0, 0, 0, 0, 0)
+	return dst
+}
+
+func AppendResultSetHeader(dst []byte, errno, affected, insertID, numFields, numRows uint32) []byte {
+	dst = append(dst, putU32(errno)...)
+	dst = append(dst, putU32(affected)...)
+	dst = append(dst, putU32(insertID)...)
+	dst = append(dst, putU32(numFields)...)
+	dst = append(dst, putU32(numRows)...)
+	dst = append(dst, make([]byte, 12)...)
+	return dst
+}
+
+func AppendField(dst []byte, name, table string, typ, flags, length uint32) []byte {
+	dst = AppendBlock(dst, []byte(name))
+	dst = AppendBlock(dst, []byte(table))
+	dst = append(dst, putU32(typ)...)
+	dst = append(dst, putU32(flags)...)
+	dst = append(dst, putU32(length)...)
+	return dst
+}
+
+func knownVersion(v uint16) bool {
+	return v == Version202 || v == Version206
+}
+
+func fmtErrno(errno uint32, msg string) string {
+	if msg == "" {
+		return fmt.Sprintf("tunnel errno %d", errno)
+	}
+	return fmt.Sprintf("tunnel errno %d: %s", errno, msg)
+}