diff options
Diffstat (limited to 'vendor/github.com/couchbase/vellum/writer.go')
-rw-r--r-- | vendor/github.com/couchbase/vellum/writer.go | 92 |
1 files changed, 92 insertions, 0 deletions
diff --git a/vendor/github.com/couchbase/vellum/writer.go b/vendor/github.com/couchbase/vellum/writer.go new file mode 100644 index 0000000000..d655d47f7f --- /dev/null +++ b/vendor/github.com/couchbase/vellum/writer.go @@ -0,0 +1,92 @@ +// Copyright (c) 2017 Couchbase, Inc. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package vellum + +import ( + "bufio" + "io" +) + +// A writer is a buffered writer used by vellum. It counts how many bytes have +// been written and has some convenience methods used for encoding the data. +type writer struct { + w *bufio.Writer + counter int +} + +func newWriter(w io.Writer) *writer { + return &writer{ + w: bufio.NewWriter(w), + } +} + +func (w *writer) Reset(newWriter io.Writer) { + w.w.Reset(newWriter) + w.counter = 0 +} + +func (w *writer) WriteByte(c byte) error { + err := w.w.WriteByte(c) + if err != nil { + return err + } + w.counter++ + return nil +} + +func (w *writer) Write(p []byte) (int, error) { + n, err := w.w.Write(p) + w.counter += n + return n, err +} + +func (w *writer) Flush() error { + return w.w.Flush() +} + +func (w *writer) WritePackedUintIn(v uint64, n int) error { + for shift := uint(0); shift < uint(n*8); shift += 8 { + err := w.WriteByte(byte(v >> shift)) + if err != nil { + return err + } + } + + return nil +} + +func (w *writer) WritePackedUint(v uint64) error { + n := packedSize(v) + return w.WritePackedUintIn(v, n) +} + +func packedSize(n uint64) int { + if n < 1<<8 { + return 1 + } else if n < 1<<16 { + return 2 + } else if n < 1<<24 { + return 3 + } else if n < 1<<32 { + return 4 + } else if n < 1<<40 { + return 5 + } else if n < 1<<48 { + return 6 + } else if n < 1<<56 { + return 7 + } + return 8 +} |