diff options
Diffstat (limited to 'vendor/github.com/jackc/pgx/v5/pgproto3/row_description.go')
-rw-r--r-- | vendor/github.com/jackc/pgx/v5/pgproto3/row_description.go | 166 |
1 files changed, 166 insertions, 0 deletions
diff --git a/vendor/github.com/jackc/pgx/v5/pgproto3/row_description.go b/vendor/github.com/jackc/pgx/v5/pgproto3/row_description.go new file mode 100644 index 0000000..dc2a4dd --- /dev/null +++ b/vendor/github.com/jackc/pgx/v5/pgproto3/row_description.go @@ -0,0 +1,166 @@ +package pgproto3 + +import ( + "bytes" + "encoding/binary" + "encoding/json" + "errors" + "math" + + "github.com/jackc/pgx/v5/internal/pgio" +) + +const ( + TextFormat = 0 + BinaryFormat = 1 +) + +type FieldDescription struct { + Name []byte + TableOID uint32 + TableAttributeNumber uint16 + DataTypeOID uint32 + DataTypeSize int16 + TypeModifier int32 + Format int16 +} + +// MarshalJSON implements encoding/json.Marshaler. +func (fd FieldDescription) MarshalJSON() ([]byte, error) { + return json.Marshal(struct { + Name string + TableOID uint32 + TableAttributeNumber uint16 + DataTypeOID uint32 + DataTypeSize int16 + TypeModifier int32 + Format int16 + }{ + Name: string(fd.Name), + TableOID: fd.TableOID, + TableAttributeNumber: fd.TableAttributeNumber, + DataTypeOID: fd.DataTypeOID, + DataTypeSize: fd.DataTypeSize, + TypeModifier: fd.TypeModifier, + Format: fd.Format, + }) +} + +type RowDescription struct { + Fields []FieldDescription +} + +// Backend identifies this message as sendable by the PostgreSQL backend. +func (*RowDescription) 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 *RowDescription) Decode(src []byte) error { + + if len(src) < 2 { + return &invalidMessageFormatErr{messageType: "RowDescription"} + } + fieldCount := int(binary.BigEndian.Uint16(src)) + rp := 2 + + dst.Fields = dst.Fields[0:0] + + for i := 0; i < fieldCount; i++ { + var fd FieldDescription + + idx := bytes.IndexByte(src[rp:], 0) + if idx < 0 { + return &invalidMessageFormatErr{messageType: "RowDescription"} + } + fd.Name = src[rp : rp+idx] + rp += idx + 1 + + // Since buf.Next() doesn't return an error if we hit the end of the buffer + // check Len ahead of time + if len(src[rp:]) < 18 { + return &invalidMessageFormatErr{messageType: "RowDescription"} + } + + fd.TableOID = binary.BigEndian.Uint32(src[rp:]) + rp += 4 + fd.TableAttributeNumber = binary.BigEndian.Uint16(src[rp:]) + rp += 2 + fd.DataTypeOID = binary.BigEndian.Uint32(src[rp:]) + rp += 4 + fd.DataTypeSize = int16(binary.BigEndian.Uint16(src[rp:])) + rp += 2 + fd.TypeModifier = int32(binary.BigEndian.Uint32(src[rp:])) + rp += 4 + fd.Format = int16(binary.BigEndian.Uint16(src[rp:])) + rp += 2 + + dst.Fields = append(dst.Fields, fd) + } + + return nil +} + +// Encode encodes src into dst. dst will include the 1 byte message type identifier and the 4 byte message length. +func (src *RowDescription) Encode(dst []byte) ([]byte, error) { + dst, sp := beginMessage(dst, 'T') + + if len(src.Fields) > math.MaxUint16 { + return nil, errors.New("too many fields") + } + dst = pgio.AppendUint16(dst, uint16(len(src.Fields))) + for _, fd := range src.Fields { + dst = append(dst, fd.Name...) + dst = append(dst, 0) + + dst = pgio.AppendUint32(dst, fd.TableOID) + dst = pgio.AppendUint16(dst, fd.TableAttributeNumber) + dst = pgio.AppendUint32(dst, fd.DataTypeOID) + dst = pgio.AppendInt16(dst, fd.DataTypeSize) + dst = pgio.AppendInt32(dst, fd.TypeModifier) + dst = pgio.AppendInt16(dst, fd.Format) + } + + return finishMessage(dst, sp) +} + +// MarshalJSON implements encoding/json.Marshaler. +func (src RowDescription) MarshalJSON() ([]byte, error) { + return json.Marshal(struct { + Type string + Fields []FieldDescription + }{ + Type: "RowDescription", + Fields: src.Fields, + }) +} + +// UnmarshalJSON implements encoding/json.Unmarshaler. +func (dst *RowDescription) UnmarshalJSON(data []byte) error { + var msg struct { + Fields []struct { + Name string + TableOID uint32 + TableAttributeNumber uint16 + DataTypeOID uint32 + DataTypeSize int16 + TypeModifier int32 + Format int16 + } + } + if err := json.Unmarshal(data, &msg); err != nil { + return err + } + dst.Fields = make([]FieldDescription, len(msg.Fields)) + for n, field := range msg.Fields { + dst.Fields[n] = FieldDescription{ + Name: []byte(field.Name), + TableOID: field.TableOID, + TableAttributeNumber: field.TableAttributeNumber, + DataTypeOID: field.DataTypeOID, + DataTypeSize: field.DataTypeSize, + TypeModifier: field.TypeModifier, + Format: field.Format, + } + } + return nil +} |