github.com/matrixorigin/matrixone@v1.2.0/pkg/common/bitmap/types.go (about)

     1  // Copyright 2021 Matrix Origin
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //      http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package bitmap
    16  
    17  import "sync/atomic"
    18  
    19  type Iterator interface {
    20  	HasNext() bool
    21  	Next() uint64
    22  	PeekNext() uint64
    23  }
    24  
    25  const (
    26  	kEmptyFlagEmpty    = 1
    27  	kEmptyFlagNotEmpty = -1
    28  	kEmptyFlagUnknown  = 0
    29  )
    30  
    31  // Bitmap represents line numbers of tuple's is null
    32  type Bitmap struct {
    33  	emptyFlag atomic.Int32 //default 0, not sure  when set to 1, must be empty. when set to -1, must be not empty
    34  	// len represents the size of bitmap
    35  	len  int64
    36  	data []uint64
    37  }
    38  
    39  type BitmapIterator struct {
    40  	i        uint64
    41  	bm       *Bitmap
    42  	has_next bool
    43  }