1 files changed, 91 insertions, 0 deletions
diff --git a/vendor/github.com/jackc/pgproto3/v2/pgproto3.go b/vendor/github.com/jackc/pgproto3/v2/pgproto3.go
new file mode 100644
index 0000000..aa4167c
--- /dev/null
+++ b/vendor/github.com/jackc/pgproto3/v2/pgproto3.go
@@ -0,0 +1,91 @@
+package pgproto3
+
+import (
+	"encoding/hex"
+	"errors"
+	"fmt"
+
+	"github.com/jackc/pgio"
+)
+
+// maxMessageBodyLen is the maximum length of a message body in bytes. See PG_LARGE_MESSAGE_LIMIT in the PostgreSQL
+// source. It is defined as (MaxAllocSize - 1). MaxAllocSize is defined as 0x3fffffff.
+const maxMessageBodyLen = (0x3fffffff - 1)
+
+// Message is the interface implemented by an object that can decode and encode
+// a particular PostgreSQL message.
+type Message interface {
+	// Decode is allowed and expected to retain a reference to data after
+	// returning (unlike encoding.BinaryUnmarshaler).
+	Decode(data []byte) error
+
+	// Encode appends itself to dst and returns the new buffer.
+	Encode(dst []byte) ([]byte, error)
+}
+
+type FrontendMessage interface {
+	Message
+	Frontend() // no-op method to distinguish frontend from backend methods
+}
+
+type BackendMessage interface {
+	Message
+	Backend() // no-op method to distinguish frontend from backend methods
+}
+
+type AuthenticationResponseMessage interface {
+	BackendMessage
+	AuthenticationResponse() // no-op method to distinguish authentication responses
+}
+
+type invalidMessageLenErr struct {
+	messageType string
+	expectedLen int
+	actualLen   int
+}
+
+func (e *invalidMessageLenErr) Error() string {
+	return fmt.Sprintf("%s body must have length of %d, but it is %d", e.messageType, e.expectedLen, e.actualLen)
+}
+
+type invalidMessageFormatErr struct {
+	messageType string
+}
+
+func (e *invalidMessageFormatErr) Error() string {
+	return fmt.Sprintf("%s body is invalid", e.messageType)
+}
+
+// getValueFromJSON gets the value from a protocol message representation in JSON.
+func getValueFromJSON(v map[string]string) ([]byte, error) {
+	if v == nil {
+		return nil, nil
+	}
+	if text, ok := v["text"]; ok {
+		return []byte(text), nil
+	}
+	if binary, ok := v["binary"]; ok {
+		return hex.DecodeString(binary)
+	}
+	return nil, errors.New("unknown protocol representation")
+}
+
+// beginMessage begines a new message of type t. It appends the message type and a placeholder for the message length to
+// dst. It returns the new buffer and the position of the message length placeholder.
+func beginMessage(dst []byte, t byte) ([]byte, int) {
+	dst = append(dst, t)
+	sp := len(dst)
+	dst = pgio.AppendInt32(dst, -1)
+	return dst, sp
+}
+
+// finishMessage finishes a message that was started with beginMessage. It computes the message length and writes it to
+// dst[sp]. If the message length is too large it returns an error. Otherwise it returns the final message buffer.
+func finishMessage(dst []byte, sp int) ([]byte, error) {
+	messageBodyLen := len(dst[sp:])
+	if messageBodyLen > maxMessageBodyLen {
+		return nil, errors.New("message body too large")
+	}
+	pgio.SetInt32(dst[sp:], int32(messageBodyLen))
+	return dst, nil
+}