mirror of
https://github.com/octoleo/restic.git
synced 2024-11-16 01:57:10 +00:00
Move RandReader to repository package
This commit is contained in:
parent
f59ffcaeae
commit
14db71d3fa
79
src/restic/repository/rand_reader.go
Normal file
79
src/restic/repository/rand_reader.go
Normal file
@ -0,0 +1,79 @@
|
||||
package repository
|
||||
|
||||
import (
|
||||
"io"
|
||||
"math/rand"
|
||||
)
|
||||
|
||||
// RandReader allows reading from a rand.Rand.
|
||||
type RandReader struct {
|
||||
rnd *rand.Rand
|
||||
buf []byte
|
||||
}
|
||||
|
||||
// NewRandReader creates a new Reader from a random source.
|
||||
func NewRandReader(rnd *rand.Rand) io.Reader {
|
||||
return &RandReader{rnd: rnd, buf: make([]byte, 0, 7)}
|
||||
}
|
||||
|
||||
func (rd *RandReader) read(p []byte) (n int, err error) {
|
||||
if len(p)%7 != 0 {
|
||||
panic("invalid buffer length, not multiple of 7")
|
||||
}
|
||||
|
||||
rnd := rd.rnd
|
||||
for i := 0; i < len(p); i += 7 {
|
||||
val := rnd.Int63()
|
||||
|
||||
p[i+0] = byte(val >> 0)
|
||||
p[i+1] = byte(val >> 8)
|
||||
p[i+2] = byte(val >> 16)
|
||||
p[i+3] = byte(val >> 24)
|
||||
p[i+4] = byte(val >> 32)
|
||||
p[i+5] = byte(val >> 40)
|
||||
p[i+6] = byte(val >> 48)
|
||||
}
|
||||
|
||||
return len(p), nil
|
||||
}
|
||||
|
||||
func (rd *RandReader) Read(p []byte) (int, error) {
|
||||
// first, copy buffer to p
|
||||
pos := copy(p, rd.buf)
|
||||
copy(rd.buf, rd.buf[pos:])
|
||||
|
||||
// shorten buf and p accordingly
|
||||
rd.buf = rd.buf[:len(rd.buf)-pos]
|
||||
p = p[pos:]
|
||||
|
||||
// if this is enough to fill p, return
|
||||
if len(p) == 0 {
|
||||
return pos, nil
|
||||
}
|
||||
|
||||
// load multiple of 7 byte
|
||||
l := (len(p) / 7) * 7
|
||||
n, err := rd.read(p[:l])
|
||||
pos += n
|
||||
if err != nil {
|
||||
return pos, err
|
||||
}
|
||||
p = p[n:]
|
||||
|
||||
// load 7 byte to temp buffer
|
||||
rd.buf = rd.buf[:7]
|
||||
n, err = rd.read(rd.buf)
|
||||
if err != nil {
|
||||
return pos, err
|
||||
}
|
||||
|
||||
// copy the remaining bytes from the buffer to p
|
||||
n = copy(p, rd.buf)
|
||||
pos += n
|
||||
|
||||
// save the remaining bytes in rd.buf
|
||||
n = copy(rd.buf, rd.buf[n:])
|
||||
rd.buf = rd.buf[:n]
|
||||
|
||||
return pos, nil
|
||||
}
|
@ -13,80 +13,9 @@ import (
|
||||
"github.com/restic/chunker"
|
||||
)
|
||||
|
||||
type randReader struct {
|
||||
rnd *rand.Rand
|
||||
buf []byte
|
||||
}
|
||||
|
||||
func newRandReader(rnd *rand.Rand) io.Reader {
|
||||
return &randReader{rnd: rnd, buf: make([]byte, 0, 7)}
|
||||
}
|
||||
|
||||
func (rd *randReader) read(p []byte) (n int, err error) {
|
||||
if len(p)%7 != 0 {
|
||||
panic("invalid buffer length, not multiple of 7")
|
||||
}
|
||||
|
||||
rnd := rd.rnd
|
||||
for i := 0; i < len(p); i += 7 {
|
||||
val := rnd.Int63()
|
||||
|
||||
p[i+0] = byte(val >> 0)
|
||||
p[i+1] = byte(val >> 8)
|
||||
p[i+2] = byte(val >> 16)
|
||||
p[i+3] = byte(val >> 24)
|
||||
p[i+4] = byte(val >> 32)
|
||||
p[i+5] = byte(val >> 40)
|
||||
p[i+6] = byte(val >> 48)
|
||||
}
|
||||
|
||||
return len(p), nil
|
||||
}
|
||||
|
||||
func (rd *randReader) Read(p []byte) (int, error) {
|
||||
// first, copy buffer to p
|
||||
pos := copy(p, rd.buf)
|
||||
copy(rd.buf, rd.buf[pos:])
|
||||
|
||||
// shorten buf and p accordingly
|
||||
rd.buf = rd.buf[:len(rd.buf)-pos]
|
||||
p = p[pos:]
|
||||
|
||||
// if this is enough to fill p, return
|
||||
if len(p) == 0 {
|
||||
return pos, nil
|
||||
}
|
||||
|
||||
// load multiple of 7 byte
|
||||
l := (len(p) / 7) * 7
|
||||
n, err := rd.read(p[:l])
|
||||
pos += n
|
||||
if err != nil {
|
||||
return pos, err
|
||||
}
|
||||
p = p[n:]
|
||||
|
||||
// load 7 byte to temp buffer
|
||||
rd.buf = rd.buf[:7]
|
||||
n, err = rd.read(rd.buf)
|
||||
if err != nil {
|
||||
return pos, err
|
||||
}
|
||||
|
||||
// copy the remaining bytes from the buffer to p
|
||||
n = copy(p, rd.buf)
|
||||
pos += n
|
||||
|
||||
// save the remaining bytes in rd.buf
|
||||
n = copy(rd.buf, rd.buf[n:])
|
||||
rd.buf = rd.buf[:n]
|
||||
|
||||
return pos, nil
|
||||
}
|
||||
|
||||
// fakeFile returns a reader which yields deterministic pseudo-random data.
|
||||
func fakeFile(t testing.TB, seed, size int64) io.Reader {
|
||||
return io.LimitReader(newRandReader(rand.New(rand.NewSource(seed))), size)
|
||||
return io.LimitReader(repository.NewRandReader(rand.New(rand.NewSource(seed))), size)
|
||||
}
|
||||
|
||||
// saveFile reads from rd and saves the blobs in the repository. The list of
|
||||
|
Loading…
Reference in New Issue
Block a user