llvm/lib/Support/Unix/Unix.h

   1 //===- llvm/Support/Unix/Unix.h - Common Unix Include File -------*- C++ -*-===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 //
   9 // This file defines things specific to Unix implementations.
  10 //
  11 //===----------------------------------------------------------------------===//
  12
  13 #ifndef LLVM_LIB_SUPPORT_UNIX_UNIX_H
  14 #define LLVM_LIB_SUPPORT_UNIX_UNIX_H
  15
  16 //===----------------------------------------------------------------------===//
  17 //=== WARNING: Implementation here must contain only generic UNIX code that
  18 //===          is guaranteed to work on all UNIX variants.
  19 //===----------------------------------------------------------------------===//
  20
  21 #include "llvm/Config/config.h"
  22 #include "llvm/Support/Chrono.h"
  23 #include "llvm/Support/Errno.h"
  24 #include "llvm/Support/ErrorHandling.h"
  25 #include <algorithm>
  26 #include <assert.h>
  27 #include <cerrno>
  28 #include <cstdio>
  29 #include <cstdlib>
  30 #include <cstring>
  31 #include <string>
  32 #include <sys/types.h>
  33 #include <sys/wait.h>
  34
  35 #ifdef HAVE_UNISTD_H
  36 #include <unistd.h>
  37 #endif
  38
  39 #ifdef HAVE_SYS_TIME_H
  40 # include <sys/time.h>
  41 #endif
  42 #include <time.h>
  43
  44 #ifdef HAVE_DLFCN_H
  45 # include <dlfcn.h>
  46 #endif
  47
  48 #ifdef HAVE_FCNTL_H
  49 # include <fcntl.h>
  50 #endif
  51
  52 /// This function builds an error message into \p ErrMsg using the \p prefix
  53 /// string and the Unix error number given by \p errnum. If errnum is -1, the
  54 /// default then the value of errno is used.
  55 /// Make an error message
  56 ///
  57 /// If the error number can be converted to a string, it will be
  58 /// separated from prefix by ": ".
  59 static inline bool MakeErrMsg(
  60   std::string* ErrMsg, const std::string& prefix, int errnum = -1) {
  61   if (!ErrMsg)
  62     return true;
  63   if (errnum == -1)
  64     errnum = errno;
  65   *ErrMsg = prefix + ": " + llvm::sys::StrError(errnum);
  66   return true;
  67 }
  68
  69 // Include StrError(errnum) in a fatal error message.
  70 [[noreturn]] static inline void ReportErrnumFatal(const char *Msg, int errnum) {
  71   std::string ErrMsg;
  72   MakeErrMsg(&ErrMsg, Msg, errnum);
  73   llvm::report_fatal_error(llvm::Twine(ErrMsg));
  74 }
  75
  76 namespace llvm {
  77 namespace sys {
  78
  79 /// Convert a struct timeval to a duration. Note that timeval can be used both
  80 /// as a time point and a duration. Be sure to check what the input represents.
  81 inline std::chrono::microseconds toDuration(const struct timeval &TV) {
  82   return std::chrono::seconds(TV.tv_sec) +
  83          std::chrono::microseconds(TV.tv_usec);
  84 }
  85
  86 /// Convert a time point to struct timespec.
  87 inline struct timespec toTimeSpec(TimePoint<> TP) {
  88   using namespace std::chrono;
  89
  90   struct timespec RetVal;
  91   RetVal.tv_sec = toTimeT(TP);
  92   RetVal.tv_nsec = (TP.time_since_epoch() % seconds(1)).count();
  93   return RetVal;
  94 }
  95
  96 /// Convert a time point to struct timeval.
  97 inline struct timeval toTimeVal(TimePoint<std::chrono::microseconds> TP) {
  98   using namespace std::chrono;
  99
 100   struct timeval RetVal;
 101   RetVal.tv_sec = toTimeT(TP);
 102   RetVal.tv_usec = (TP.time_since_epoch() % seconds(1)).count();
 103   return RetVal;
 104 }
 105
 106 } // namespace sys
 107 } // namespace llvm
 108
 109 #endif