LLVM 17.0.0git
FileUtilities.h
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1//===- llvm/Support/FileUtilities.h - File System Utilities -----*- 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 a family of utility functions which are useful for doing
10// various things with files.
11//
12//===----------------------------------------------------------------------===//
13
14#ifndef LLVM_SUPPORT_FILEUTILITIES_H
15#define LLVM_SUPPORT_FILEUTILITIES_H
16
17#include "llvm/ADT/StringRef.h"
18#include "llvm/Support/Error.h"
20
21#include <system_error>
22
23namespace llvm {
24
25 /// DiffFilesWithTolerance - Compare the two files specified, returning 0 if
26 /// the files match, 1 if they are different, and 2 if there is a file error.
27 /// This function allows you to specify an absolute and relative FP error that
28 /// is allowed to exist. If you specify a string to fill in for the error
29 /// option, it will set the string to an error message if an error occurs, or
30 /// if the files are different.
31 ///
32 int DiffFilesWithTolerance(StringRef FileA,
33 StringRef FileB,
34 double AbsTol, double RelTol,
35 std::string *Error = nullptr);
36
37
38 /// FileRemover - This class is a simple object meant to be stack allocated.
39 /// If an exception is thrown from a region, the object removes the filename
40 /// specified (if deleteIt is true).
41 ///
43 SmallString<128> Filename;
44 bool DeleteIt;
45 public:
46 FileRemover() : DeleteIt(false) {}
47
48 explicit FileRemover(const Twine& filename, bool deleteIt = true)
49 : DeleteIt(deleteIt) {
50 filename.toVector(Filename);
51 }
52
54 if (DeleteIt) {
55 // Ignore problems deleting the file.
56 sys::fs::remove(Filename);
57 }
58 }
59
60 /// setFile - Give ownership of the file to the FileRemover so it will
61 /// be removed when the object is destroyed. If the FileRemover already
62 /// had ownership of a file, remove it first.
63 void setFile(const Twine& filename, bool deleteIt = true) {
64 if (DeleteIt) {
65 // Ignore problems deleting the file.
66 sys::fs::remove(Filename);
67 }
68
69 Filename.clear();
70 filename.toVector(Filename);
71 DeleteIt = deleteIt;
72 }
73
74 /// releaseFile - Take ownership of the file away from the FileRemover so it
75 /// will not be removed when the object is destroyed.
76 void releaseFile() { DeleteIt = false; }
77 };
78
79 enum class atomic_write_error {
83 };
84
85 class AtomicFileWriteError : public llvm::ErrorInfo<AtomicFileWriteError> {
86 public:
88
89 void log(raw_ostream &OS) const override;
90
92 static char ID;
93
94 private:
95 // Users are not expected to use error_code.
96 std::error_code convertToErrorCode() const override {
98 }
99 };
100
101 // atomic_write_error + whatever the Writer can return
102
103 /// Creates a unique file with name according to the given \p TempPathModel,
104 /// writes content of \p Buffer to the file and renames it to \p FinalPath.
105 ///
106 /// \returns \c AtomicFileWriteError in case of error.
107 llvm::Error writeFileAtomically(StringRef TempPathModel, StringRef FinalPath,
108 StringRef Buffer);
109
111 writeFileAtomically(StringRef TempPathModel, StringRef FinalPath,
112 std::function<llvm::Error(llvm::raw_ostream &)> Writer);
113
114 /// FilePermssionsApplier helps to copy permissions from an input file to
115 /// an output one. It memorizes the status of the input file and can apply
116 /// permissions and dates to the output file.
118 public:
120
121 /// Apply stored permissions to the \p OutputFilename.
122 /// Copy LastAccess and ModificationTime if \p CopyDates is true.
123 /// Overwrite stored permissions if \p OverwritePermissions is specified.
124 Error
125 apply(StringRef OutputFilename, bool CopyDates = false,
126 std::optional<sys::fs::perms> OverwritePermissions = std::nullopt);
127
128 private:
130 : InputFilename(InputFilename), InputStatus(Status) {}
131
132 StringRef InputFilename;
133 sys::fs::file_status InputStatus;
134 };
135} // End llvm namespace
136
137#endif
static cl::opt< std::string > OutputFilename("o", cl::desc("Output filename"), cl::value_desc("filename"), cl::init("-"))
raw_pwrite_stream & OS
const atomic_write_error Error
Definition: FileUtilities.h:91
void log(raw_ostream &OS) const override
Print an error message to an output stream.
AtomicFileWriteError(atomic_write_error Error)
Definition: FileUtilities.h:87
Base class for user error types.
Definition: Error.h:348
Lightweight error class with error context and mandatory checking.
Definition: Error.h:156
Tagged union holding either a T or a Error.
Definition: Error.h:470
FilePermssionsApplier helps to copy permissions from an input file to an output one.
Error apply(StringRef OutputFilename, bool CopyDates=false, std::optional< sys::fs::perms > OverwritePermissions=std::nullopt)
Apply stored permissions to the OutputFilename.
static Expected< FilePermissionsApplier > create(StringRef InputFilename)
FileRemover - This class is a simple object meant to be stack allocated.
Definition: FileUtilities.h:42
FileRemover(const Twine &filename, bool deleteIt=true)
Definition: FileUtilities.h:48
void setFile(const Twine &filename, bool deleteIt=true)
setFile - Give ownership of the file to the FileRemover so it will be removed when the object is dest...
Definition: FileUtilities.h:63
void releaseFile()
releaseFile - Take ownership of the file away from the FileRemover so it will not be removed when the...
Definition: FileUtilities.h:76
SmallString - A SmallString is just a SmallVector with methods and accessors that make it work better...
Definition: SmallString.h:26
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:50
Twine - A lightweight data structure for efficiently representing the concatenation of temporary valu...
Definition: Twine.h:81
This class implements an extremely fast bulk output stream that can only output to a stream.
Definition: raw_ostream.h:52
Represents the result of a call to sys::fs::status().
Definition: FileSystem.h:226
std::error_code remove(const Twine &path, bool IgnoreNonExisting=true)
Remove path.
This is an optimization pass for GlobalISel generic memory operations.
Definition: AddressRanges.h:18
llvm::Error writeFileAtomically(StringRef TempPathModel, StringRef FinalPath, StringRef Buffer)
Creates a unique file with name according to the given TempPathModel, writes content of Buffer to the...
std::error_code inconvertibleErrorCode()
The value returned by this function can be returned from convertToErrorCode for Error values where no...
Definition: Error.cpp:79
atomic_write_error
Definition: FileUtilities.h:79
int DiffFilesWithTolerance(StringRef FileA, StringRef FileB, double AbsTol, double RelTol, std::string *Error=nullptr)
DiffFilesWithTolerance - Compare the two files specified, returning 0 if the files match,...