LLVM  10.0.0svn
Unix.h
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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 <algorithm>
25 #include <assert.h>
26 #include <cerrno>
27 #include <cstdio>
28 #include <cstdlib>
29 #include <cstring>
30 #include <string>
31 #include <sys/types.h>
32 #include <sys/wait.h>
33 
34 #ifdef HAVE_UNISTD_H
35 #include <unistd.h>
36 #endif
37 
38 #ifdef HAVE_SYS_PARAM_H
39 #include <sys/param.h>
40 #endif
41 
42 #ifdef HAVE_SYS_TIME_H
43 # include <sys/time.h>
44 #endif
45 #include <time.h>
46 
47 #ifdef HAVE_DLFCN_H
48 # include <dlfcn.h>
49 #endif
50 
51 #ifdef HAVE_FCNTL_H
52 # include <fcntl.h>
53 #endif
54 
55 /// This function builds an error message into \p ErrMsg using the \p prefix
56 /// string and the Unix error number given by \p errnum. If errnum is -1, the
57 /// default then the value of errno is used.
58 /// Make an error message
59 ///
60 /// If the error number can be converted to a string, it will be
61 /// separated from prefix by ": ".
62 static inline bool MakeErrMsg(
63  std::string* ErrMsg, const std::string& prefix, int errnum = -1) {
64  if (!ErrMsg)
65  return true;
66  if (errnum == -1)
67  errnum = errno;
68  *ErrMsg = prefix + ": " + llvm::sys::StrError(errnum);
69  return true;
70 }
71 
72 namespace llvm {
73 namespace sys {
74 
75 /// Convert a struct timeval to a duration. Note that timeval can be used both
76 /// as a time point and a duration. Be sure to check what the input represents.
77 inline std::chrono::microseconds toDuration(const struct timeval &TV) {
78  return std::chrono::seconds(TV.tv_sec) +
79  std::chrono::microseconds(TV.tv_usec);
80 }
81 
82 /// Convert a time point to struct timespec.
83 inline struct timespec toTimeSpec(TimePoint<> TP) {
84  using namespace std::chrono;
85 
86  struct timespec RetVal;
87  RetVal.tv_sec = toTimeT(TP);
88  RetVal.tv_nsec = (TP.time_since_epoch() % seconds(1)).count();
89  return RetVal;
90 }
91 
92 /// Convert a time point to struct timeval.
93 inline struct timeval toTimeVal(TimePoint<std::chrono::microseconds> TP) {
94  using namespace std::chrono;
95 
96  struct timeval RetVal;
97  RetVal.tv_sec = toTimeT(TP);
98  RetVal.tv_usec = (TP.time_since_epoch() % seconds(1)).count();
99  return RetVal;
100 }
101 
102 } // namespace sys
103 } // namespace llvm
104 
105 #endif
This class represents lattice values for constants.
Definition: AllocatorList.h:23
struct timespec toTimeSpec(TimePoint<> TP)
Convert a time point to struct timespec.
Definition: Unix.h:83
Definition: BitVector.h:937
std::string StrError()
Returns a string representation of the errno value, using whatever thread-safe variant of strerror() ...
Definition: Errno.cpp:31
auto count(R &&Range, const E &Element) -> typename std::iterator_traits< decltype(adl_begin(Range))>::difference_type
Wrapper function around std::count to count the number of times an element Element occurs in the give...
Definition: STLExtras.h:1231
std::time_t toTimeT(TimePoint<> TP)
Convert a TimePoint to std::time_t.
Definition: Chrono.h:36
struct timeval toTimeVal(TimePoint< std::chrono::microseconds > TP)
Convert a time point to struct timeval.
Definition: Unix.h:93
std::chrono::microseconds toDuration(const struct timeval &TV)
Convert a struct timeval to a duration.
Definition: Unix.h:77
static bool MakeErrMsg(std::string *ErrMsg, const std::string &prefix, int errnum=-1)
This function builds an error message into ErrMsg using the prefix string and the Unix error number g...
Definition: Unix.h:62
std::chrono::time_point< std::chrono::system_clock, D > TimePoint
A time point on the system clock.
Definition: Chrono.h:33