LLVM  11.0.0git
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"
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 LLVM_ATTRIBUTE_NORETURN static inline void ReportErrnumFatal(const char *Msg,
71  int errnum) {
72  std::string ErrMsg;
73  MakeErrMsg(&ErrMsg, Msg, errnum);
75 }
76 
77 namespace llvm {
78 namespace sys {
79 
80 /// Convert a struct timeval to a duration. Note that timeval can be used both
81 /// as a time point and a duration. Be sure to check what the input represents.
82 inline std::chrono::microseconds toDuration(const struct timeval &TV) {
83  return std::chrono::seconds(TV.tv_sec) +
84  std::chrono::microseconds(TV.tv_usec);
85 }
86 
87 /// Convert a time point to struct timespec.
88 inline struct timespec toTimeSpec(TimePoint<> TP) {
89  using namespace std::chrono;
90 
91  struct timespec RetVal;
92  RetVal.tv_sec = toTimeT(TP);
93  RetVal.tv_nsec = (TP.time_since_epoch() % seconds(1)).count();
94  return RetVal;
95 }
96 
97 /// Convert a time point to struct timeval.
98 inline struct timeval toTimeVal(TimePoint<std::chrono::microseconds> TP) {
99  using namespace std::chrono;
100 
101  struct timeval RetVal;
102  RetVal.tv_sec = toTimeT(TP);
103  RetVal.tv_usec = (TP.time_since_epoch() % seconds(1)).count();
104  return RetVal;
105 }
106 
107 } // namespace sys
108 } // namespace llvm
109 
110 #endif
This class represents lattice values for constants.
Definition: AllocatorList.h:23
LLVM_ATTRIBUTE_NORETURN void report_fatal_error(Error Err, bool gen_crash_diag=true)
Report a serious error, calling any installed error handler.
Definition: Error.cpp:140
struct timespec toTimeSpec(TimePoint<> TP)
Convert a time point to struct timespec.
Definition: Unix.h:88
Definition: BitVector.h:959
std::string StrError()
Returns a string representation of the errno value, using whatever thread-safe variant of strerror() ...
Definition: Errno.cpp:31
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:98
#define LLVM_ATTRIBUTE_NORETURN
Definition: Compiler.h:249
static LLVM_ATTRIBUTE_NORETURN void ReportErrnumFatal(const char *Msg, int errnum)
Definition: Unix.h:70
auto count(R &&Range, const E &Element)
Wrapper function around std::count to count the number of times an element Element occurs in the give...
Definition: STLExtras.h:1567
std::chrono::nanoseconds toDuration(FILETIME Time)
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:59
std::chrono::time_point< std::chrono::system_clock, D > TimePoint
A time point on the system clock.
Definition: Chrono.h:33