vendor: Add github.com/cznic/lldb and friends (new recursive dependency)

vendor/github.com/cznic/internal/buffer/LICENSE

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+Copyright (c) 2016 The Internal Authors. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+   * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+   * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+   * Neither the names of the authors nor the names of the
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

vendor/github.com/cznic/internal/buffer/buffer.go

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+// Copyright 2016 The Internal Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package buffer implements a pool of pointers to byte slices.
+//
+// Example usage pattern
+//
+//	p := buffer.Get(size)
+//	b := *p	// Now you can use b in any way you need.
+//	...
+//	// When b will not be used anymore
+//	buffer.Put(p)
+//	...
+//	// If b or p are not going out of scope soon, optionally
+//	b = nil
+//	p = nil
+//
+// Otherwise the pool cannot release the buffer on garbage collection.
+//
+// Do not do
+//
+//	p := buffer.Get(size)
+//	b := *p
+//	...
+//	buffer.Put(&b)
+//
+// or
+//
+//	b := *buffer.Get(size)
+//	...
+//	buffer.Put(&b)
+package buffer
+
+import (
+	"github.com/cznic/internal/slice"
+)
+
+// CGet returns a pointer to a byte slice of len size. The pointed to byte
+// slice is zeroed up to its cap. CGet panics for size < 0.
+//
+// CGet is safe for concurrent use by multiple goroutines.
+func CGet(size int) *[]byte { return slice.Bytes.CGet(size).(*[]byte) }
+
+// Get returns a pointer to a byte slice of len size. The pointed to byte slice
+// is not zeroed. Get panics for size < 0.
+//
+// Get is safe for concurrent use by multiple goroutines.
+func Get(size int) *[]byte { return slice.Bytes.Get(size).(*[]byte) }
+
+// Put puts a pointer to a byte slice into a pool for possible later reuse by
+// CGet or Get.
+//
+// Put is safe for concurrent use by multiple goroutines.
+func Put(p *[]byte) { slice.Bytes.Put(p) }