github.com/gitbundle/modules@v0.0.0-20231025071548-85b91c5c3b01/queue/bytefifo.go (about)

     1  // Copyright 2023 The GitBundle Inc. All rights reserved.
     2  // Copyright 2017 The Gitea Authors. All rights reserved.
     3  // Use of this source code is governed by a MIT-style
     4  // license that can be found in the LICENSE file.
     5  
     6  package queue
     7  
     8  import "context"
     9  
    10  // ByteFIFO defines a FIFO that takes a byte array
    11  type ByteFIFO interface {
    12  	// Len returns the length of the fifo
    13  	Len(ctx context.Context) int64
    14  	// PushFunc pushes data to the end of the fifo and calls the callback if it is added
    15  	PushFunc(ctx context.Context, data []byte, fn func() error) error
    16  	// Pop pops data from the start of the fifo
    17  	Pop(ctx context.Context) ([]byte, error)
    18  	// Close this fifo
    19  	Close() error
    20  	// PushBack pushes data back to the top of the fifo
    21  	PushBack(ctx context.Context, data []byte) error
    22  }
    23  
    24  // UniqueByteFIFO defines a FIFO that Uniques its contents
    25  type UniqueByteFIFO interface {
    26  	ByteFIFO
    27  	// Has returns whether the fifo contains this data
    28  	Has(ctx context.Context, data []byte) (bool, error)
    29  }
    30  
    31  var _ ByteFIFO = &DummyByteFIFO{}
    32  
    33  // DummyByteFIFO represents a dummy fifo
    34  type DummyByteFIFO struct{}
    35  
    36  // PushFunc returns nil
    37  func (*DummyByteFIFO) PushFunc(ctx context.Context, data []byte, fn func() error) error {
    38  	return nil
    39  }
    40  
    41  // Pop returns nil
    42  func (*DummyByteFIFO) Pop(ctx context.Context) ([]byte, error) {
    43  	return []byte{}, nil
    44  }
    45  
    46  // Close returns nil
    47  func (*DummyByteFIFO) Close() error {
    48  	return nil
    49  }
    50  
    51  // Len is always 0
    52  func (*DummyByteFIFO) Len(ctx context.Context) int64 {
    53  	return 0
    54  }
    55  
    56  // PushBack pushes data back to the top of the fifo
    57  func (*DummyByteFIFO) PushBack(ctx context.Context, data []byte) error {
    58  	return nil
    59  }
    60  
    61  var _ UniqueByteFIFO = &DummyUniqueByteFIFO{}
    62  
    63  // DummyUniqueByteFIFO represents a dummy unique fifo
    64  type DummyUniqueByteFIFO struct {
    65  	DummyByteFIFO
    66  }
    67  
    68  // Has always returns false
    69  func (*DummyUniqueByteFIFO) Has(ctx context.Context, data []byte) (bool, error) {
    70  	return false, nil
    71  }