For the macro, I believe ARROW_ASSIGN_OR_RAISE already does this? On Thu, May 27, 2021 at 1:19 PM Benjamin Kietzman <bengil...@gmail.com> wrote:
> unique_ptr is used to designate unique ownership of the buffer > just created. It's fairly compatible with shared_ptr since > unique_ptr can convert implicitly to shared_ptr. > > One other refactoring in play here: we've been moving from > Status-returning-out-argument functions to the more ergonomic > Result<T>. I'd recommend you write a new macro for dealing with > Result<T>s, like: > > #define ASSIGN_OR_THROW_IMPL(result_name, lhs, rexpr) \ > auto&& result_name = (rexpr); \ > THROW_NOT_OK((result_name).status()); \ > lhs = std::move(result_name).ValueUnsafe(); > #define ASSIGN_OR_THROW(lhs, rexpr) \ > ASSIGN_OR_THROW_IMPL(_maybe ## __COUNTER__, lhs, rexpr) > > Then lines such as > https://github.com/Paradigm4/bridge/blob/master/src/Driver.h#L196 > can be rewritten as: > > ASSIGN_OR_THROW(buffer, arrow::AllocateBuffer(length)); > > Does that help? > > On Thu, May 27, 2021 at 3:47 PM Rares Vernica <rvern...@gmail.com> wrote: > > > Hello, > > > > We are trying to migrate from Arrow 0.16.0 to a newer version, hopefully > up > > to 4.0.0. The Arrow 0.17.0 change in AllocateBuffer from taking a > > shared_ptr<Buffer> to returning a unique_ptr<Buffer> is making things > very > > difficult. We wonder if there is a strong reason behind the change from > > shared_ptr to unique_ptr and if there is an easier path forward for us. > > > > In our code, we interchangeably use Buffer and ResizableBuffer. We pass > > around these pointers across a number of classes. They are allocated or > > resized here > > https://github.com/Paradigm4/bridge/blob/master/src/Driver.h#L191 > > Moreover, > > we cast the ResizableBuffer instance to Buffer in order to have all our > > methods only deal with Buffer, here > > https://github.com/Paradigm4/bridge/blob/master/src/Driver.h#L151 > > > > In Arrow 0.16.0 AllocateBuffer took a shared_ptr<Buffer> and this works > > fine. In Arrow 0.17.0 AllocateBuffer returns a unique_ptr<Buffer>. Our > cast > > from ResizableBuffer to Buffer won't work on unique_ptr and we won't be > > able to pass the Buffer around so easily. > > > > I noticed that there is another AllocateBuffer in MemoryManger that > returns > > a shared_ptr. > > > > > https://arrow.apache.org/docs/cpp/api/memory.html?highlight=resizablebuffer#_CPPv4N5arrow13MemoryManager14AllocateBufferE7int64_t > > Is this a better alternative to allocate a buffer? Is there a similar > > method to allocate a resizable buffer? > > > > Thank you, > > Rares > > >
