blob: 34b0811dacf45a4692eea1aa15f1d7752b806de7 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
|
// Package buffer implements a series of Buffers which can be composed to implement complicated buffering strategies
package buffer
import (
"io"
"os"
)
// Buffer is used to Write() data which will be Read() later.
type Buffer interface {
Len() int64 // How much data is Buffered in bytes
Cap() int64 // How much data can be Buffered at once in bytes.
io.Reader // Read() will read from the top of the buffer [io.EOF if empty]
io.Writer // Write() will write to the end of the buffer [io.ErrShortWrite if not enough space]
Reset() // Truncates the buffer, Len() == 0.
}
// BufferAt is a buffer which supports io.ReaderAt and io.WriterAt
type BufferAt interface {
Buffer
io.ReaderAt
io.WriterAt
}
func len64(p []byte) int64 {
return int64(len(p))
}
// Gap returns buf.Cap() - buf.Len()
func Gap(buf Buffer) int64 {
return buf.Cap() - buf.Len()
}
// Full returns true iff buf.Len() == buf.Cap()
func Full(buf Buffer) bool {
return buf.Len() == buf.Cap()
}
// Empty returns false iff buf.Len() == 0
func Empty(buf Buffer) bool {
return buf.Len() == 0
}
// NewUnboundedBuffer returns a Buffer which buffers "mem" bytes to memory
// and then creates file's of size "file" to buffer above "mem" bytes.
func NewUnboundedBuffer(mem, file int64) Buffer {
return NewMulti(New(mem), NewPartition(NewFilePool(file, os.TempDir())))
}
|
