// // Copyright Aliaksei Levin (levlam@telegram.org), Arseny Smirnov (arseny30@gmail.com) 2014-2023 // // Distributed under the Boost Software License, Version 1.0. (See accompanying // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) // #pragma once #include "td/utils/StringBuilder.h" #include <atomic> namespace td { class PollFlags { public: using Raw = int32; bool can_read() const { return has_flags(Read()); } bool can_write() const { return has_flags(Write()); } bool can_close() const { return has_flags(Close()); } bool has_pending_error() const { return has_flags(Error()); } void remove_flags(PollFlags flags) { remove_flags(flags.raw()); } bool add_flags(PollFlags flags) { auto old_flags = flags_; add_flags(flags.raw()); return old_flags != flags_; } bool has_flags(PollFlags flags) const { return has_flags(flags.raw()); } bool empty() const { return flags_ == 0; } Raw raw() const { return flags_; } static PollFlags from_raw(Raw raw) { return PollFlags(raw); } PollFlags() = default; bool operator==(const PollFlags &other) const { return flags_ == other.flags_; } bool operator!=(const PollFlags &other) const { return !(*this == other); } PollFlags operator|(const PollFlags other) const { return from_raw(raw() | other.raw()); } static PollFlags Write() { return PollFlags(Flag::Write); } static PollFlags Error() { return PollFlags(Flag::Error); } static PollFlags Close() { return PollFlags(Flag::Close); } static PollFlags Read() { return PollFlags(Flag::Read); } static PollFlags ReadWrite() { return Read() | Write(); } private: enum class Flag : Raw { Write = 0x001, Read = 0x002, Close = 0x004, Error = 0x008, None = 0 }; Raw flags_{static_cast<Raw>(Flag::None)}; explicit PollFlags(Raw raw) : flags_(raw) { } explicit PollFlags(Flag flag) : PollFlags(static_cast<Raw>(flag)) { } PollFlags &add_flags(Raw flags) { flags_ |= flags; return *this; } PollFlags &remove_flags(Raw flags) { flags_ &= ~flags; return *this; } bool has_flags(Raw flags) const { return (flags_ & flags) == flags; } }; StringBuilder &operator<<(StringBuilder &sb, PollFlags flags); class PollFlagsSet { public: // write flags from any thread // this is the only function that should be called from other threads bool write_flags(PollFlags flags); bool write_flags_local(PollFlags flags); bool flush() const; PollFlags read_flags() const; PollFlags read_flags_local() const; void clear_flags(PollFlags flags); void clear(); private: mutable std::atomic<PollFlags::Raw> to_write_{0}; mutable PollFlags flags_; }; } // namespace td