refactor code structure for gnet

redis/parser/parserv2.go

@@ -0,0 +1,122 @@
+package parser
+
+import (
+	"errors"
+	"io"
+	"strconv"
+	"strings"
+)
+
+func ParseV2(r io.Reader) ([][]byte, error) {
+	// 读取起始字符 '*'
+	buf := make([]byte, 1)
+	_, err := io.ReadFull(r, buf)
+	if err != nil {
+		return nil, err
+	}
+	if buf[0] != '*' {
+		// try text protocol
+		buf2, err := readLine(r)
+		if err != nil {
+			return nil, err
+		}
+		buf = append(buf, buf2...)
+		line := strings.Split(string(buf), " ")
+		result := make([][]byte, len(line))
+		for i, s := range line {
+			result[i] = []byte(s)
+		}
+		return result, nil
+	}
+
+	// 读取参数数量
+	count, err := readInteger(r)
+	if err != nil {
+		return nil, err
+	}
+	if count < 0 {
+		return nil, nil
+	}
+
+	// 读取每个参数
+	result := make([][]byte, count)
+	for i := 0; i < count; i++ {
+		// 读取类型前缀
+		_, err := io.ReadFull(r, buf)
+		if err != nil {
+			return nil, err
+		}
+
+		switch buf[0] {
+		case '$': // Bulk String
+			strLen, err := readInteger(r)
+			if err != nil {
+				return nil, err
+			}
+			if strLen < 0 {
+				result[i] = nil // Null Bulk String
+				continue
+			}
+
+			data := make([]byte, strLen+2)
+			_, err = io.ReadFull(r, data)
+			if err != nil {
+				return nil, err
+			}
+			result[i] = data[:strLen]
+
+		// case '+', ':': // Simple String or Integer
+		// 	simpleStr, err := readLine(r)
+		// 	if err != nil {
+		// 		return nil, err
+		// 	}
+		// 	result[i] = []byte(simpleStr)
+
+		// case '-': // Error
+		// 	errStr, err := readLine(r)
+		// 	if err != nil {
+		// 		return nil, err
+		// 	}
+		// 	result[i] = []byte(errStr)
+
+		default:
+			return nil, errors.New("unsupported RESP type")
+		}
+	}
+
+	return result, nil
+}
+
+func readInteger(r io.Reader) (int, error) {
+	line, err := readLine(r)
+	if err != nil {
+		return 0, err
+	}
+	return strconv.Atoi(string(line))
+}
+
+func readLine(r io.Reader) ([]byte, error) {
+	var line []byte
+	buf := make([]byte, 1)
+
+	for {
+		_, err := io.ReadFull(r, buf)
+		if err != nil {
+			return nil, err
+		}
+
+		switch buf[0] {
+		case '\r':
+			_, err := io.ReadFull(r, buf)
+			if err != nil {
+				return nil, errors.New("unexpected EOF after \\r")
+			}
+			if buf[0] != '\n' {
+				return nil, errors.New("expected \\n after \\r")
+			}
+			return line, nil
+		default:
+			line = append(line, buf[0])
+		}
+	}
+}