| //===-- SelectHelper.h ------------------------------------------*- C++ -*-===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #ifndef liblldb_SelectHelper_h_ |
| #define liblldb_SelectHelper_h_ |
| |
| #include "lldb/Utility/Status.h" // for Status |
| #include "lldb/lldb-types.h" // for socket_t |
| |
| #include "llvm/ADT/DenseMap.h" |
| #include "llvm/ADT/Optional.h" |
| |
| #include <chrono> |
| |
| class SelectHelper { |
| public: |
| // Defaults to infinite wait for select unless you call SetTimeout() |
| SelectHelper(); |
| |
| // Call SetTimeout() before calling SelectHelper::Select() to set the timeout |
| // based on the current time + the timeout. This allows multiple calls to |
| // SelectHelper::Select() without having to worry about the absolute timeout |
| // as this class manages to set the relative timeout correctly. |
| void SetTimeout(const std::chrono::microseconds &timeout); |
| |
| // Call the FDSet*() functions before calling SelectHelper::Select() to set |
| // the file descriptors that we will watch for when calling select. This will |
| // cause FD_SET() to be called prior to calling select using the "fd" |
| // provided. |
| void FDSetRead(lldb::socket_t fd); |
| void FDSetWrite(lldb::socket_t fd); |
| void FDSetError(lldb::socket_t fd); |
| |
| // Call the FDIsSet*() functions after calling SelectHelper::Select() to |
| // check which file descriptors are ready for read/write/error. This will |
| // contain the result of FD_ISSET after calling select for a given file |
| // descriptor. |
| bool FDIsSetRead(lldb::socket_t fd) const; |
| bool FDIsSetWrite(lldb::socket_t fd) const; |
| bool FDIsSetError(lldb::socket_t fd) const; |
| |
| // Call the system's select() to wait for descriptors using timeout provided |
| // in a call the SelectHelper::SetTimeout(), or infinite wait if no timeout |
| // was set. |
| lldb_private::Status Select(); |
| |
| protected: |
| struct FDInfo { |
| FDInfo() |
| : read_set(false), write_set(false), error_set(false), |
| read_is_set(false), write_is_set(false), error_is_set(false) {} |
| |
| void PrepareForSelect() { |
| read_is_set = false; |
| write_is_set = false; |
| error_is_set = false; |
| } |
| |
| bool read_set : 1, write_set : 1, error_set : 1, read_is_set : 1, |
| write_is_set : 1, error_is_set : 1; |
| }; |
| llvm::DenseMap<lldb::socket_t, FDInfo> m_fd_map; |
| llvm::Optional<std::chrono::steady_clock::time_point> m_end_time; |
| }; |
| |
| #endif // liblldb_SelectHelper_h_ |