================ @@ -0,0 +1,146 @@ +//===-- Transport.cpp -----------------------------------------------------===// +// +// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. +// See https://llvm.org/LICENSE.txt for license information. +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// +//===----------------------------------------------------------------------===// + +#include "Transport.h" +#include "Protocol.h" +#include "c++/v1/__system_error/error_code.h" +#include "lldb/Utility/IOObject.h" +#include "lldb/Utility/Status.h" +#include "lldb/lldb-forward.h" +#include "llvm/ADT/StringExtras.h" +#include "llvm/Support/Error.h" +#include "llvm/Support/raw_ostream.h" +#include <string> +#include <system_error> +#include <utility> + +using namespace llvm; +using namespace lldb; +using namespace lldb_private; +using namespace lldb_dap; +using namespace lldb_dap::protocol; + +static Expected<std::string> ReadFull(IOObjectSP &descriptor, size_t length) { + if (!descriptor || !descriptor->IsValid()) + return createStringError("transport input is closed"); + + std::string data; + data.resize(length); + + auto status = descriptor->Read(data.data(), length); + if (status.Fail()) + return status.takeError(); + + // If we got back zero then we have reached EOF. + if (length == 0) + return createStringError(Transport::kEOF, "end-of-file"); + + return data.substr(0, length); +} + +static Expected<std::string> ReadUntil(IOObjectSP &descriptor, + StringRef delimiter) { + std::string buffer; + buffer.reserve(delimiter.size() + 1); + while (!llvm::StringRef(buffer).ends_with(delimiter)) { + auto next = ReadFull(descriptor, 1); + if (auto Err = next.takeError()) + return std::move(Err); + buffer += *next; + } + return buffer.substr(0, buffer.size() - delimiter.size()); +} + +static Error ReadExpected(IOObjectSP &descriptor, StringRef want) { + auto got = ReadFull(descriptor, want.size()); + if (auto Err = got.takeError()) + return Err; + if (*got != want) { + return createStringError("want %s, got %s", want.str().c_str(), + got->c_str()); + } + return Error::success(); +} + +namespace lldb_dap { + +const std::error_code Transport::kEOF = + std::error_code(0x1001, std::generic_category()); ---------------- labath wrote:
Hmm... I can't say I like the repetitiveness of of the log statements in the Read function, nor the fact that `Read` and `Write` methods handle errors differently (one logs while the other returns them). What exactly was making that complicated? Another option would be to return an `Expected<optional<Message>>` with a `nullopt` meaning "EOF". It's a bit of a mouthful, but we do have APIs like that, and it doesn't look like this function will be used from that many places. https://github.com/llvm/llvm-project/pull/130026 _______________________________________________ lldb-commits mailing list lldb-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/lldb-commits
