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Diffstat (limited to 'vendor/github.com/jackc/pgx/v5/pgproto3/pgproto3.go')
-rw-r--r--vendor/github.com/jackc/pgx/v5/pgproto3/pgproto3.go120
1 files changed, 120 insertions, 0 deletions
diff --git a/vendor/github.com/jackc/pgx/v5/pgproto3/pgproto3.go b/vendor/github.com/jackc/pgx/v5/pgproto3/pgproto3.go
new file mode 100644
index 0000000..128f97f
--- /dev/null
+++ b/vendor/github.com/jackc/pgx/v5/pgproto3/pgproto3.go
@@ -0,0 +1,120 @@
+package pgproto3
+
+import (
+ "encoding/hex"
+ "errors"
+ "fmt"
+
+ "github.com/jackc/pgx/v5/internal/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)
+}
+
+// FrontendMessage is a message sent by the frontend (i.e. the client).
+type FrontendMessage interface {
+ Message
+ Frontend() // no-op method to distinguish frontend from backend methods
+}
+
+// BackendMessage is a message sent by the backend (i.e. the server).
+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
+ details string
+}
+
+func (e *invalidMessageFormatErr) Error() string {
+ return fmt.Sprintf("%s body is invalid %s", e.messageType, e.details)
+}
+
+type writeError struct {
+ err error
+ safeToRetry bool
+}
+
+func (e *writeError) Error() string {
+ return fmt.Sprintf("write failed: %s", e.err.Error())
+}
+
+func (e *writeError) SafeToRetry() bool {
+ return e.safeToRetry
+}
+
+func (e *writeError) Unwrap() error {
+ return e.err
+}
+
+type ExceededMaxBodyLenErr struct {
+ MaxExpectedBodyLen int
+ ActualBodyLen int
+}
+
+func (e *ExceededMaxBodyLenErr) Error() string {
+ return fmt.Sprintf("invalid body length: expected at most %d, but got %d", e.MaxExpectedBodyLen, e.ActualBodyLen)
+}
+
+// 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 begins 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
+}