github.com/m3db/m3@v1.5.0/src/x/pool/checked_bytes.go (about)

     1  // Copyright (c) 2016 Uber Technologies, Inc.
     2  //
     3  // Permission is hereby granted, free of charge, to any person obtaining a copy
     4  // of this software and associated documentation files (the "Software"), to deal
     5  // in the Software without restriction, including without limitation the rights
     6  // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
     7  // copies of the Software, and to permit persons to whom the Software is
     8  // furnished to do so, subject to the following conditions:
     9  //
    10  // The above copyright notice and this permission notice shall be included in
    11  // all copies or substantial portions of the Software.
    12  //
    13  // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
    14  // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
    15  // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
    16  // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
    17  // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
    18  // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
    19  // THE SOFTWARE.
    20  
    21  package pool
    22  
    23  import "github.com/m3db/m3/src/x/checked"
    24  
    25  type checkedBytesPool struct {
    26  	bytesPool BytesPool
    27  	pool      BucketizedObjectPool
    28  }
    29  
    30  // NewBytesPoolFn is a function to construct a new bytes pool
    31  type NewBytesPoolFn func(sizes []Bucket) BytesPool
    32  
    33  // NewCheckedBytesPool creates a new checked bytes pool
    34  func NewCheckedBytesPool(
    35  	sizes []Bucket,
    36  	opts ObjectPoolOptions,
    37  	newBackingBytesPool NewBytesPoolFn,
    38  ) CheckedBytesPool {
    39  	return &checkedBytesPool{
    40  		bytesPool: newBackingBytesPool(sizes),
    41  		pool:      NewBucketizedObjectPool(sizes, opts),
    42  	}
    43  }
    44  
    45  func (p *checkedBytesPool) BytesPool() BytesPool {
    46  	return p.bytesPool
    47  }
    48  
    49  func (p *checkedBytesPool) Init() {
    50  	opts := checked.NewBytesOptions().
    51  		SetFinalizer(p)
    52  
    53  	p.bytesPool.Init()
    54  	p.pool.Init(func(capacity int) interface{} {
    55  		value := p.bytesPool.Get(capacity)
    56  		return checked.NewBytes(value, opts)
    57  	})
    58  }
    59  
    60  func (p *checkedBytesPool) Get(capacity int) checked.Bytes {
    61  	return p.pool.Get(capacity).(checked.Bytes)
    62  }
    63  
    64  func (p *checkedBytesPool) FinalizeBytes(bytes checked.Bytes) {
    65  	bytes.IncRef()
    66  	bytes.Resize(0)
    67  	capacity := bytes.Cap()
    68  	bytes.DecRef()
    69  	p.pool.Put(bytes, capacity)
    70  }
    71  
    72  // AppendByteChecked appends a byte to a byte slice getting a new slice from
    73  // the CheckedBytesPool if the slice is at capacity
    74  func AppendByteChecked(
    75  	bytes checked.Bytes,
    76  	b byte,
    77  	pool CheckedBytesPool,
    78  ) (
    79  	result checked.Bytes,
    80  	swapped bool,
    81  ) {
    82  	orig := bytes
    83  
    84  	if bytes.Len() == bytes.Cap() {
    85  		newBytes := pool.Get(bytes.Cap() * 2)
    86  
    87  		// Inc the ref to read/write to it
    88  		newBytes.IncRef()
    89  		newBytes.Resize(bytes.Len())
    90  
    91  		copy(newBytes.Bytes(), bytes.Bytes())
    92  
    93  		bytes = newBytes
    94  	}
    95  
    96  	bytes.Append(b)
    97  
    98  	result = bytes
    99  	swapped = orig != bytes
   100  
   101  	if swapped {
   102  		// No longer holding reference from the inc
   103  		result.DecRef()
   104  	}
   105  
   106  	return
   107  }