86 lines
1.5 KiB
Go
86 lines
1.5 KiB
Go
package mmap_span
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import (
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"io"
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"launchpad.net/gommap"
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)
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type segment struct {
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gommap.MMap
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}
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func (me segment) Size() int64 {
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return int64(len(me.MMap))
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}
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type MMapSpan struct {
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span
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}
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func (me *MMapSpan) Append(mmap gommap.MMap) {
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me.span = append(me.span, segment{mmap})
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}
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func (me MMapSpan) Close() {
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for _, mMap := range me.span {
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mMap.(segment).UnsafeUnmap()
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}
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}
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func (me MMapSpan) Size() (ret int64) {
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for _, seg := range me.span {
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ret += seg.Size()
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}
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return
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}
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func (me MMapSpan) ReadAt(p []byte, off int64) (n int, err error) {
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me.ApplyTo(off, func(intervalOffset int64, interval sizer) (stop bool) {
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_n := copy(p, interval.(segment).MMap[intervalOffset:])
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p = p[_n:]
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n += _n
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return len(p) == 0
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})
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if len(p) != 0 {
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err = io.EOF
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}
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return
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}
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func (me MMapSpan) WriteSectionTo(w io.Writer, off, n int64) (written int64, err error) {
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me.ApplyTo(off, func(intervalOffset int64, interval sizer) (stop bool) {
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var _n int
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p := interval.(segment).MMap[intervalOffset:]
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if n < int64(len(p)) {
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p = p[:n]
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}
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_n, err = w.Write(p)
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written += int64(_n)
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n -= int64(_n)
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if err != nil {
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return true
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}
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return n == 0
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})
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return
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}
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func (me MMapSpan) WriteAt(p []byte, off int64) (n int, err error) {
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me.ApplyTo(off, func(iOff int64, i sizer) (stop bool) {
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mMap := i.(segment)
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_n := copy(mMap.MMap[iOff:], p)
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// err = mMap.Sync(gommap.MS_ASYNC)
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// if err != nil {
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// return true
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// }
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p = p[_n:]
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n += _n
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return len(p) == 0
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})
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if err != nil && len(p) != 0 {
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err = io.ErrShortWrite
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}
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return
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}
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