36 lines
732 B
Go
36 lines
732 B
Go
package fuse
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import "unsafe"
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// buffer provides a mechanism for constructing a message from
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// multiple segments.
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type buffer []byte
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// alloc allocates size bytes and returns a pointer to the new
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// segment.
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func (w *buffer) alloc(size uintptr) unsafe.Pointer {
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s := int(size)
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if len(*w)+s > cap(*w) {
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old := *w
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*w = make([]byte, len(*w), 2*cap(*w)+s)
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copy(*w, old)
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}
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l := len(*w)
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*w = (*w)[:l+s]
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return unsafe.Pointer(&(*w)[l])
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}
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// reset clears out the contents of the buffer.
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func (w *buffer) reset() {
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for i := range (*w)[:cap(*w)] {
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(*w)[i] = 0
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}
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*w = (*w)[:0]
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}
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func newBuffer(extra uintptr) buffer {
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const hdrSize = unsafe.Sizeof(outHeader{})
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buf := make(buffer, hdrSize, hdrSize+extra)
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return buf
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}
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