mirror of https://github.com/jetkvm/kvm.git
60 lines
1.4 KiB
Go
60 lines
1.4 KiB
Go
// SPDX-FileCopyrightText: 2023 The Pion community <https://pion.ly>
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// SPDX-License-Identifier: MIT
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package srtp
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import (
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"bytes"
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"unsafe"
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)
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// growBufferSize grows the buffer size to the given number of bytes.
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func growBufferSize(buf []byte, size int) []byte {
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if size <= cap(buf) {
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return buf[:size]
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}
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buf2 := make([]byte, size)
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copy(buf2, buf)
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return buf2
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}
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// allocateIfMismatch checks if buffers match, if not allocates a new buffer and returns it.
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func allocateIfMismatch(dst, src []byte) []byte {
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if dst == nil {
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dst = make([]byte, len(src))
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copy(dst, src)
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} else if !bytes.Equal(dst, src) { // bytes.Equal returns on ref equality, no optimization needed
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extraNeeded := len(src) - len(dst)
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if extraNeeded > 0 {
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dst = append(dst, make([]byte, extraNeeded)...) //nolint:makezero // todo: fix
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} else if extraNeeded < 0 {
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dst = dst[:len(dst)+extraNeeded]
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}
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copy(dst, src)
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}
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return dst
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}
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// isSameBuffer returns true if slices a and b share the same underlying buffer.
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func isSameBuffer(a, b []byte) bool {
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// If both are nil, they are technically the same (no buffer)
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if a == nil && b == nil {
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return true
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}
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// If either is nil, or both have 0 capacity, they can't share backing buffer
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if cap(a) == 0 || cap(b) == 0 {
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return false
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}
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// Create a slice of length 1 from each if possible
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aPtr := unsafe.Pointer(&a[:1][0]) // nolint:gosec
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bPtr := unsafe.Pointer(&b[:1][0]) // nolint:gosec
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return aPtr == bPtr
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}
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