Unix.h revision 360784 
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_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/// Make an error message
60///
61/// If the error number can be converted to a string, it will be
62/// separated from prefix by ": ".
63static 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// Include StrError(errnum) in a fatal error message.
74LLVM_ATTRIBUTE_NORETURN static inline void ReportErrnumFatal(const char *Msg,
75                                                             int errnum) {
76  std::string ErrMsg;
77  MakeErrMsg(&ErrMsg, Msg, errnum);
78  llvm::report_fatal_error(ErrMsg);
79}
80
81namespace llvm {
82namespace sys {
83
84/// Convert a struct timeval to a duration. Note that timeval can be used both
85/// as a time point and a duration. Be sure to check what the input represents.
86inline std::chrono::microseconds toDuration(const struct timeval &TV) {
87  return std::chrono::seconds(TV.tv_sec) +
88         std::chrono::microseconds(TV.tv_usec);
89}
90
91/// Convert a time point to struct timespec.
92inline struct timespec toTimeSpec(TimePoint<> TP) {
93  using namespace std::chrono;
94
95  struct timespec RetVal;
96  RetVal.tv_sec = toTimeT(TP);
97  RetVal.tv_nsec = (TP.time_since_epoch() % seconds(1)).count();
98  return RetVal;
99}
100
101/// Convert a time point to struct timeval.
102inline struct timeval toTimeVal(TimePoint<std::chrono::microseconds> TP) {
103  using namespace std::chrono;
104
105  struct timeval RetVal;
106  RetVal.tv_sec = toTimeT(TP);
107  RetVal.tv_usec = (TP.time_since_epoch() % seconds(1)).count();
108  return RetVal;
109}
110
111} // namespace sys
112} // namespace llvm
113
114#endif
115