LLVM  6.0.0svn
Unix.h
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1 //===- llvm/Support/Unix/Unix.h - Common Unix Include File -------*- C++ -*-===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file defines things specific to Unix implementations.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #ifndef LLVM_LIB_SUPPORT_UNIX_UNIX_H
15 #define LLVM_LIB_SUPPORT_UNIX_UNIX_H
16 
17 //===----------------------------------------------------------------------===//
18 //=== WARNING: Implementation here must contain only generic UNIX code that
19 //=== is guaranteed to work on all UNIX variants.
20 //===----------------------------------------------------------------------===//
21 
22 #include "llvm/Config/config.h" // Get autoconf configuration settings
23 #include "llvm/Support/Chrono.h"
24 #include "llvm/Support/Errno.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_PARAM_H
40 #include <sys/param.h>
41 #endif
42 
43 #ifdef HAVE_SYS_TIME_H
44 # include <sys/time.h>
45 #endif
46 #include <time.h>
47 
48 #ifdef HAVE_DLFCN_H
49 # include <dlfcn.h>
50 #endif
51 
52 #ifdef HAVE_FCNTL_H
53 # include <fcntl.h>
54 #endif
55 
56 /// This function builds an error message into \p ErrMsg using the \p prefix
57 /// string and the Unix error number given by \p errnum. If errnum is -1, the
58 /// default then the value of errno is used.
59 /// @brief Make an error message
60 ///
61 /// If the error number can be converted to a string, it will be
62 /// separated from prefix by ": ".
63 static inline bool MakeErrMsg(
64  std::string* ErrMsg, const std::string& prefix, int errnum = -1) {
65  if (!ErrMsg)
66  return true;
67  if (errnum == -1)
68  errnum = errno;
69  *ErrMsg = prefix + ": " + llvm::sys::StrError(errnum);
70  return true;
71 }
72 
73 namespace llvm {
74 namespace sys {
75 
76 /// Convert a struct timeval to a duration. Note that timeval can be used both
77 /// as a time point and a duration. Be sure to check what the input represents.
78 inline std::chrono::microseconds toDuration(const struct timeval &TV) {
79  return std::chrono::seconds(TV.tv_sec) +
80  std::chrono::microseconds(TV.tv_usec);
81 }
82 
83 /// Convert a time point to struct timespec.
84 inline struct timespec toTimeSpec(TimePoint<> TP) {
85  using namespace std::chrono;
86 
87  struct timespec RetVal;
88  RetVal.tv_sec = toTimeT(TP);
89  RetVal.tv_nsec = (TP.time_since_epoch() % seconds(1)).count();
90  return RetVal;
91 }
92 
93 /// Convert a time point to struct timeval.
94 inline struct timeval toTimeVal(TimePoint<std::chrono::microseconds> TP) {
95  using namespace std::chrono;
96 
97  struct timeval RetVal;
98  RetVal.tv_sec = toTimeT(TP);
99  RetVal.tv_usec = (TP.time_since_epoch() % seconds(1)).count();
100  return RetVal;
101 }
102 
103 } // namespace sys
104 } // namespace llvm
105 
106 #endif
LLVM_ATTRIBUTE_ALWAYS_INLINE std::time_t toTimeT(TimePoint<> TP)
Convert a TimePoint to std::time_t.
Definition: Chrono.h:37
Compute iterated dominance frontiers using a linear time algorithm.
Definition: AllocatorList.h:24
struct timespec toTimeSpec(TimePoint<> TP)
Convert a time point to struct timespec.
Definition: Unix.h:84
Definition: BitVector.h:920
std::string StrError()
Returns a string representation of the errno value, using whatever thread-safe variant of strerror() ...
Definition: Errno.cpp:32
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:874
struct timeval toTimeVal(TimePoint< std::chrono::microseconds > TP)
Convert a time point to struct timeval.
Definition: Unix.h:94
std::chrono::microseconds toDuration(const struct timeval &TV)
Convert a struct timeval to a duration.
Definition: Unix.h:78
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:63
std::chrono::time_point< std::chrono::system_clock, D > TimePoint
A time point on the system clock.
Definition: Chrono.h:34