Initial commit

vendor/github.com/jackc/pgproto3/v2/data_row.go

@@ -0,0 +1,142 @@
+package pgproto3
+
+import (
+	"encoding/binary"
+	"encoding/hex"
+	"encoding/json"
+
+	"github.com/jackc/pgio"
+)
+
+type DataRow struct {
+	Values [][]byte
+}
+
+// Backend identifies this message as sendable by the PostgreSQL backend.
+func (*DataRow) Backend() {}
+
+// Decode decodes src into dst. src must contain the complete message with the exception of the initial 1 byte message
+// type identifier and 4 byte message length.
+func (dst *DataRow) Decode(src []byte) error {
+	if len(src) < 2 {
+		return &invalidMessageFormatErr{messageType: "DataRow"}
+	}
+	rp := 0
+	fieldCount := int(binary.BigEndian.Uint16(src[rp:]))
+	rp += 2
+
+	// If the capacity of the values slice is too small OR substantially too
+	// large reallocate. This is too avoid one row with many columns from
+	// permanently allocating memory.
+	if cap(dst.Values) < fieldCount || cap(dst.Values)-fieldCount > 32 {
+		newCap := 32
+		if newCap < fieldCount {
+			newCap = fieldCount
+		}
+		dst.Values = make([][]byte, fieldCount, newCap)
+	} else {
+		dst.Values = dst.Values[:fieldCount]
+	}
+
+	for i := 0; i < fieldCount; i++ {
+		if len(src[rp:]) < 4 {
+			return &invalidMessageFormatErr{messageType: "DataRow"}
+		}
+
+		msgSize := int(int32(binary.BigEndian.Uint32(src[rp:])))
+		rp += 4
+
+		// null
+		if msgSize == -1 {
+			dst.Values[i] = nil
+		} else {
+			if len(src[rp:]) < msgSize {
+				return &invalidMessageFormatErr{messageType: "DataRow"}
+			}
+
+			dst.Values[i] = src[rp : rp+msgSize : rp+msgSize]
+			rp += msgSize
+		}
+	}
+
+	return nil
+}
+
+// Encode encodes src into dst. dst will include the 1 byte message type identifier and the 4 byte message length.
+func (src *DataRow) Encode(dst []byte) []byte {
+	dst = append(dst, 'D')
+	sp := len(dst)
+	dst = pgio.AppendInt32(dst, -1)
+
+	dst = pgio.AppendUint16(dst, uint16(len(src.Values)))
+	for _, v := range src.Values {
+		if v == nil {
+			dst = pgio.AppendInt32(dst, -1)
+			continue
+		}
+
+		dst = pgio.AppendInt32(dst, int32(len(v)))
+		dst = append(dst, v...)
+	}
+
+	pgio.SetInt32(dst[sp:], int32(len(dst[sp:])))
+
+	return dst
+}
+
+// MarshalJSON implements encoding/json.Marshaler.
+func (src DataRow) MarshalJSON() ([]byte, error) {
+	formattedValues := make([]map[string]string, len(src.Values))
+	for i, v := range src.Values {
+		if v == nil {
+			continue
+		}
+
+		var hasNonPrintable bool
+		for _, b := range v {
+			if b < 32 {
+				hasNonPrintable = true
+				break
+			}
+		}
+
+		if hasNonPrintable {
+			formattedValues[i] = map[string]string{"binary": hex.EncodeToString(v)}
+		} else {
+			formattedValues[i] = map[string]string{"text": string(v)}
+		}
+	}
+
+	return json.Marshal(struct {
+		Type   string
+		Values []map[string]string
+	}{
+		Type:   "DataRow",
+		Values: formattedValues,
+	})
+}
+
+// UnmarshalJSON implements encoding/json.Unmarshaler.
+func (dst *DataRow) UnmarshalJSON(data []byte) error {
+	// Ignore null, like in the main JSON package.
+	if string(data) == "null" {
+		return nil
+	}
+
+	var msg struct {
+		Values []map[string]string
+	}
+	if err := json.Unmarshal(data, &msg); err != nil {
+		return err
+	}
+
+	dst.Values = make([][]byte, len(msg.Values))
+	for n, parameter := range msg.Values {
+		var err error
+		dst.Values[n], err = getValueFromJSON(parameter)
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}