| // Copyright 2015 Google Inc. All rights reserved |
| // |
| // 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 kati |
| |
| import ( |
| "bytes" |
| "io" |
| "sync" |
| ) |
| |
| var bufFree = sync.Pool{ |
| New: func() interface{} { return new(buffer) }, |
| } |
| |
| func writeByte(w io.Writer, b byte) error { |
| if bw, ok := w.(io.ByteWriter); ok { |
| return bw.WriteByte(b) |
| } |
| _, err := w.Write([]byte{b}) |
| return err |
| } |
| |
| // use io.WriteString to stringWrite. |
| |
| type ssvWriter struct { |
| io.Writer |
| space bool |
| } |
| |
| func (w *ssvWriter) writeWord(word []byte) { |
| if w.space { |
| writeByte(w.Writer, ' ') |
| } |
| w.space = true |
| w.Writer.Write(word) |
| } |
| |
| func (w *ssvWriter) writeWordString(word string) { |
| if w.space { |
| writeByte(w.Writer, ' ') |
| } |
| w.space = true |
| io.WriteString(w.Writer, word) |
| } |
| |
| func (w *ssvWriter) resetSpace() { |
| w.space = false |
| } |
| |
| type buffer struct { |
| bytes.Buffer |
| ssvWriter |
| args [][]byte |
| } |
| |
| func newBuf() *buffer { |
| buf := bufFree.Get().(*buffer) |
| buf.Reset() |
| return buf |
| } |
| |
| func freeBuf(buf *buffer) { |
| if cap(buf.Bytes()) > 1024 { |
| return |
| } |
| buf.Reset() |
| buf.args = buf.args[:0] |
| bufFree.Put(buf) |
| } |
| |
| func (b *buffer) Reset() { |
| b.Buffer.Reset() |
| b.resetSpace() |
| } |
| |
| func (b *buffer) resetSpace() { |
| if b.ssvWriter.Writer == nil { |
| b.ssvWriter.Writer = &b.Buffer |
| } |
| b.ssvWriter.resetSpace() |
| } |
| |
| type wordBuffer struct { |
| words [][]byte |
| cont bool |
| } |
| |
| func (wb *wordBuffer) Write(data []byte) (int, error) { |
| if len(data) == 0 { |
| return 0, nil |
| } |
| if isWhitespace(rune(data[0])) { |
| wb.cont = false |
| } |
| ws := newWordScanner(data) |
| for ws.Scan() { |
| if wb.cont { |
| word := wb.words[len(wb.words)-1] |
| word = append(word, ws.Bytes()...) |
| wb.words[len(wb.words)-1] = word |
| wb.cont = false |
| continue |
| } |
| wb.writeWord(ws.Bytes()) |
| } |
| if !isWhitespace(rune(data[len(data)-1])) { |
| wb.cont = true |
| } |
| return len(data), nil |
| } |
| |
| func (wb *wordBuffer) writeWord(word []byte) { |
| var w []byte |
| w = append(w, word...) |
| wb.words = append(wb.words, w) |
| } |
| |
| func (wb *wordBuffer) writeWordString(word string) { |
| wb.writeWord([]byte(word)) |
| } |
| |
| func (wb *wordBuffer) resetSpace() {} |
| |
| func (wb *wordBuffer) Bytes() []byte { |
| var sp bool |
| var b []byte |
| for _, word := range wb.words { |
| if sp { |
| b = append(b, ' ') |
| } |
| b = append(b, word...) |
| sp = true |
| } |
| return b |
| } |