1 // Copyright 2024 The Pigweed Authors 2 // 3 // Licensed under the Apache License, Version 2.0 (the "License"); you may not 4 // use this file except in compliance with the License. You may obtain a copy of 5 // the License at 6 // 7 // https://www.apache.org/licenses/LICENSE-2.0 8 // 9 // Unless required by applicable law or agreed to in writing, software 10 // distributed under the License is distributed on an "AS IS" BASIS, WITHOUT 11 // WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the 12 // License for the specific language governing permissions and limitations under 13 // the License. 14 #pragma once 15 16 #include "pw_allocator/allocator.h" 17 #include "pw_function/function.h" 18 #include "pw_multibuf/multibuf.h" 19 20 namespace pw::multibuf { 21 22 /// Creates a multibuf from an existing span and a ``deleter`` callback. 23 /// 24 /// The provided allocator is used to allocate storage for the chunk-tracking 25 /// metadata. The allocator's lifetime must outlive the returned ``MultiBuf``. 26 /// 27 /// Returns ``nullopt`` if the ``metadata_allocator`` fails to allocate a 28 /// metadata region to track the provided buffer. In this case, ``deleter`` 29 /// will not be invoked and the caller will retain ownership of the provided 30 /// region. 31 std::optional<MultiBuf> FromSpan(pw::Allocator& metadata_allocator, 32 ByteSpan region, 33 pw::Function<void(ByteSpan)>&& deleter); 34 35 } // namespace pw::multibuf 36