ref: 0587025b7d48bae29b0843c2c4ab691b99f82752
dir: /buffers.go/
package furgit
import "sync"
const (
defaultBodyCap = 32 * 1024
maxPooledBody = 8 << 20
)
type borrowedBody struct {
buf []byte
pooled bool
}
var bodyPool = sync.Pool{
New: func() any {
buf := make([]byte, 0, defaultBodyCap)
return &buf
},
}
func borrowBody(capHint int) borrowedBody {
if capHint < defaultBodyCap {
capHint = defaultBodyCap
}
buf := bodyPool.Get().(*[]byte)
if cap(*buf) < capHint {
bodyPool.Put(buf)
newBuf := make([]byte, 0, capHint)
return borrowedBody{buf: newBuf, pooled: false}
}
slice := (*buf)[:0]
return borrowedBody{buf: slice, pooled: true}
}
func borrowedFromOwned(buf []byte) borrowedBody {
return borrowedBody{buf: buf}
}
func (b *borrowedBody) Resize(n int) {
if n < 0 {
n = 0
}
b.ensureCapacity(n)
b.buf = b.buf[:n]
}
func (b *borrowedBody) Append(src []byte) {
if len(src) == 0 {
return
}
start := len(b.buf)
b.ensureCapacity(start + len(src))
b.buf = b.buf[:start+len(src)]
copy(b.buf[start:], src)
}
func (b *borrowedBody) Bytes() []byte {
return b.buf
}
func (b *borrowedBody) Release() {
if b.buf == nil {
return
}
if b.pooled && cap(b.buf) <= maxPooledBody {
tmp := b.buf[:0]
bodyPool.Put(&tmp)
}
b.buf = nil
b.pooled = false
}
func (b *borrowedBody) ensureCapacity(needed int) {
if cap(b.buf) >= needed {
return
}
old := b.buf
wasPooled := b.pooled
newCap := cap(b.buf) * 2
if newCap < needed {
newCap = needed
}
newBuf := make([]byte, len(b.buf), newCap)
copy(newBuf, b.buf)
b.buf = newBuf
b.pooled = false
if wasPooled && cap(old) <= maxPooledBody {
tmp := old[:0]
bodyPool.Put(&tmp)
}
}