Timeout.h revision 341825
1311128Sdim//===-- Timeout.h -----------------------------------------------*- C++ -*-===// 2311128Sdim// 3311128Sdim// The LLVM Compiler Infrastructure 4311128Sdim// 5311128Sdim// This file is distributed under the University of Illinois Open Source 6311128Sdim// License. See LICENSE.TXT for details. 7311128Sdim// 8311128Sdim//===----------------------------------------------------------------------===// 9311128Sdim 10311128Sdim#ifndef liblldb_Timeout_h_ 11311128Sdim#define liblldb_Timeout_h_ 12311128Sdim 13311128Sdim#include "llvm/ADT/Optional.h" 14321369Sdim#include "llvm/Support/Chrono.h" 15321369Sdim#include "llvm/Support/FormatProviders.h" 16311128Sdim 17311128Sdimnamespace lldb_private { 18311128Sdim 19311128Sdim// A general purpose class for representing timeouts for various APIs. It's 20311128Sdim// basically an llvm::Optional<std::chrono::duration<int64_t, Ratio>>, but we 21311128Sdim// customize it a bit to enable the standard chrono implicit conversions (e.g. 22311128Sdim// from Timeout<std::milli> to Timeout<std::micro>. 23311128Sdim// 24311128Sdim// The intended meaning of the values is: 25341825Sdim// - llvm::None - no timeout, the call should wait forever - 0 - poll, only 26341825Sdim// complete the call if it will not block - >0 - wait for a given number of 27341825Sdim// units for the result 28311128Sdimtemplate <typename Ratio> 29311128Sdimclass Timeout : public llvm::Optional<std::chrono::duration<int64_t, Ratio>> { 30311128Sdimprivate: 31311128Sdim template <typename Ratio2> using Dur = std::chrono::duration<int64_t, Ratio2>; 32311128Sdim template <typename Rep2, typename Ratio2> 33311128Sdim using EnableIf = std::enable_if< 34311128Sdim std::is_convertible<std::chrono::duration<Rep2, Ratio2>, 35311128Sdim std::chrono::duration<int64_t, Ratio>>::value>; 36311128Sdim 37311128Sdim using Base = llvm::Optional<Dur<Ratio>>; 38311128Sdim 39311128Sdimpublic: 40311128Sdim Timeout(llvm::NoneType none) : Base(none) {} 41311128Sdim Timeout(const Timeout &other) = default; 42311128Sdim 43311128Sdim template <typename Ratio2, 44311128Sdim typename = typename EnableIf<int64_t, Ratio2>::type> 45311128Sdim Timeout(const Timeout<Ratio2> &other) 46311128Sdim : Base(other ? Base(Dur<Ratio>(*other)) : llvm::None) {} 47311128Sdim 48311128Sdim template <typename Rep2, typename Ratio2, 49311128Sdim typename = typename EnableIf<Rep2, Ratio2>::type> 50311128Sdim Timeout(const std::chrono::duration<Rep2, Ratio2> &other) 51311128Sdim : Base(Dur<Ratio>(other)) {} 52311128Sdim}; 53311128Sdim 54311128Sdim} // namespace lldb_private 55311128Sdim 56321369Sdimnamespace llvm { 57321369Sdimtemplate<typename Ratio> 58321369Sdimstruct format_provider<lldb_private::Timeout<Ratio>, void> { 59321369Sdim static void format(const lldb_private::Timeout<Ratio> &timeout, 60321369Sdim raw_ostream &OS, StringRef Options) { 61321369Sdim typedef typename lldb_private::Timeout<Ratio>::value_type Dur; 62321369Sdim 63321369Sdim if (!timeout) 64321369Sdim OS << "<infinite>"; 65321369Sdim else 66321369Sdim format_provider<Dur>::format(*timeout, OS, Options); 67321369Sdim } 68321369Sdim}; 69321369Sdim} 70321369Sdim 71311128Sdim#endif // liblldb_Timeout_h_ 72