github.com/vedadiyan/sqlparser@v1.0.0/pkg/bytes2/buffer.go (about)

     1  /*
     2  Copyright 2019 The Vitess Authors.
     3  
     4  Licensed under the Apache License, Version 2.0 (the "License");
     5  you may not use this file except in compliance with the License.
     6  You may obtain a copy of the License at
     7  
     8      http://www.apache.org/licenses/LICENSE-2.0
     9  
    10  Unless required by applicable law or agreed to in writing, software
    11  distributed under the License is distributed on an "AS IS" BASIS,
    12  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13  See the License for the specific language governing permissions and
    14  limitations under the License.
    15  */
    16  
    17  package bytes2
    18  
    19  import "unsafe"
    20  
    21  // Buffer implements a subset of the write portion of
    22  // bytes.Buffer, but more efficiently. This is meant to
    23  // be used in very high QPS operations, especially for
    24  // WriteByte, and without abstracting it as a Writer.
    25  // Function signatures contain errors for compatibility,
    26  // but they do not return errors.
    27  type Buffer struct {
    28  	bytes []byte
    29  }
    30  
    31  // NewBuffer is equivalent to bytes.NewBuffer.
    32  func NewBuffer(b []byte) *Buffer {
    33  	return &Buffer{bytes: b}
    34  }
    35  
    36  // Write is equivalent to bytes.Buffer.Write.
    37  func (buf *Buffer) Write(b []byte) (int, error) {
    38  	buf.bytes = append(buf.bytes, b...)
    39  	return len(b), nil
    40  }
    41  
    42  // WriteString is equivalent to bytes.Buffer.WriteString.
    43  func (buf *Buffer) WriteString(s string) (int, error) {
    44  	buf.bytes = append(buf.bytes, s...)
    45  	return len(s), nil
    46  }
    47  
    48  // WriteByte is equivalent to bytes.Buffer.WriteByte.
    49  func (buf *Buffer) WriteByte(b byte) error {
    50  	buf.bytes = append(buf.bytes, b)
    51  	return nil
    52  }
    53  
    54  // Bytes is equivalent to bytes.Buffer.Bytes.
    55  func (buf *Buffer) Bytes() []byte {
    56  	return buf.bytes
    57  }
    58  
    59  // Strings is equivalent to bytes.Buffer.Strings.
    60  func (buf *Buffer) String() string {
    61  	return string(buf.bytes)
    62  }
    63  
    64  // StringUnsafe is equivalent to String, but the copy of the string that it returns
    65  // is _not_ allocated, so modifying this buffer after calling StringUnsafe will lead
    66  // to undefined behavior.
    67  func (buf *Buffer) StringUnsafe() string {
    68  	return *(*string)(unsafe.Pointer(&buf.bytes))
    69  }
    70  
    71  // Reset is equivalent to bytes.Buffer.Reset.
    72  func (buf *Buffer) Reset() {
    73  	buf.bytes = buf.bytes[:0]
    74  }
    75  
    76  // Len is equivalent to bytes.Buffer.Len.
    77  func (buf *Buffer) Len() int {
    78  	return len(buf.bytes)
    79  }