| //===- Support/FileUtilities.cpp - File System Utilities ------------------===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file implements a family of utility functions which are useful for doing |
| // various things with files. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "llvm/Support/FileUtilities.h" |
| #include "llvm/ADT/SmallString.h" |
| #include "llvm/ADT/StringExtras.h" |
| #include "llvm/Support/Error.h" |
| #include "llvm/Support/ErrorOr.h" |
| #include "llvm/Support/MemoryBuffer.h" |
| #include "llvm/Support/Process.h" |
| #include "llvm/Support/raw_ostream.h" |
| #include <cmath> |
| #include <cstdint> |
| #include <cstdlib> |
| #include <cstring> |
| #include <memory> |
| #include <system_error> |
| |
| using namespace llvm; |
| |
| static bool isSignedChar(char C) { |
| return (C == '+' || C == '-'); |
| } |
| |
| static bool isExponentChar(char C) { |
| switch (C) { |
| case 'D': // Strange exponential notation. |
| case 'd': // Strange exponential notation. |
| case 'e': |
| case 'E': return true; |
| default: return false; |
| } |
| } |
| |
| static bool isNumberChar(char C) { |
| switch (C) { |
| case '0': case '1': case '2': case '3': case '4': |
| case '5': case '6': case '7': case '8': case '9': |
| case '.': return true; |
| default: return isSignedChar(C) || isExponentChar(C); |
| } |
| } |
| |
| static const char *BackupNumber(const char *Pos, const char *FirstChar) { |
| // If we didn't stop in the middle of a number, don't backup. |
| if (!isNumberChar(*Pos)) return Pos; |
| |
| // Otherwise, return to the start of the number. |
| bool HasPeriod = false; |
| while (Pos > FirstChar && isNumberChar(Pos[-1])) { |
| // Backup over at most one period. |
| if (Pos[-1] == '.') { |
| if (HasPeriod) |
| break; |
| HasPeriod = true; |
| } |
| |
| --Pos; |
| if (Pos > FirstChar && isSignedChar(Pos[0]) && !isExponentChar(Pos[-1])) |
| break; |
| } |
| return Pos; |
| } |
| |
| /// EndOfNumber - Return the first character that is not part of the specified |
| /// number. This assumes that the buffer is null terminated, so it won't fall |
| /// off the end. |
| static const char *EndOfNumber(const char *Pos) { |
| while (isNumberChar(*Pos)) |
| ++Pos; |
| return Pos; |
| } |
| |
| /// CompareNumbers - compare two numbers, returning true if they are different. |
| static bool CompareNumbers(const char *&F1P, const char *&F2P, |
| const char *F1End, const char *F2End, |
| double AbsTolerance, double RelTolerance, |
| std::string *ErrorMsg) { |
| const char *F1NumEnd, *F2NumEnd; |
| double V1 = 0.0, V2 = 0.0; |
| |
| // If one of the positions is at a space and the other isn't, chomp up 'til |
| // the end of the space. |
| while (isSpace(static_cast<unsigned char>(*F1P)) && F1P != F1End) |
| ++F1P; |
| while (isSpace(static_cast<unsigned char>(*F2P)) && F2P != F2End) |
| ++F2P; |
| |
| // If we stop on numbers, compare their difference. |
| if (!isNumberChar(*F1P) || !isNumberChar(*F2P)) { |
| // The diff failed. |
| F1NumEnd = F1P; |
| F2NumEnd = F2P; |
| } else { |
| // Note that some ugliness is built into this to permit support for numbers |
| // that use "D" or "d" as their exponential marker, e.g. "1.234D45". This |
| // occurs in 200.sixtrack in spec2k. |
| V1 = strtod(F1P, const_cast<char**>(&F1NumEnd)); |
| V2 = strtod(F2P, const_cast<char**>(&F2NumEnd)); |
| |
| if (*F1NumEnd == 'D' || *F1NumEnd == 'd') { |
| // Copy string into tmp buffer to replace the 'D' with an 'e'. |
| SmallString<200> StrTmp(F1P, EndOfNumber(F1NumEnd)+1); |
| // Strange exponential notation! |
| StrTmp[static_cast<unsigned>(F1NumEnd-F1P)] = 'e'; |
| |
| V1 = strtod(&StrTmp[0], const_cast<char**>(&F1NumEnd)); |
| F1NumEnd = F1P + (F1NumEnd-&StrTmp[0]); |
| } |
| |
| if (*F2NumEnd == 'D' || *F2NumEnd == 'd') { |
| // Copy string into tmp buffer to replace the 'D' with an 'e'. |
| SmallString<200> StrTmp(F2P, EndOfNumber(F2NumEnd)+1); |
| // Strange exponential notation! |
| StrTmp[static_cast<unsigned>(F2NumEnd-F2P)] = 'e'; |
| |
| V2 = strtod(&StrTmp[0], const_cast<char**>(&F2NumEnd)); |
| F2NumEnd = F2P + (F2NumEnd-&StrTmp[0]); |
| } |
| } |
| |
| if (F1NumEnd == F1P || F2NumEnd == F2P) { |
| if (ErrorMsg) { |
| *ErrorMsg = "FP Comparison failed, not a numeric difference between '"; |
| *ErrorMsg += F1P[0]; |
| *ErrorMsg += "' and '"; |
| *ErrorMsg += F2P[0]; |
| *ErrorMsg += "'"; |
| } |
| return true; |
| } |
| |
| // Check to see if these are inside the absolute tolerance |
| if (AbsTolerance < std::abs(V1-V2)) { |
| // Nope, check the relative tolerance... |
| double Diff; |
| if (V2) |
| Diff = std::abs(V1/V2 - 1.0); |
| else if (V1) |
| Diff = std::abs(V2/V1 - 1.0); |
| else |
| Diff = 0; // Both zero. |
| if (Diff > RelTolerance) { |
| if (ErrorMsg) { |
| raw_string_ostream(*ErrorMsg) |
| << "Compared: " << V1 << " and " << V2 << '\n' |
| << "abs. diff = " << std::abs(V1-V2) << " rel.diff = " << Diff << '\n' |
| << "Out of tolerance: rel/abs: " << RelTolerance << '/' |
| << AbsTolerance; |
| } |
| return true; |
| } |
| } |
| |
| // Otherwise, advance our read pointers to the end of the numbers. |
| F1P = F1NumEnd; F2P = F2NumEnd; |
| return false; |
| } |
| |
| /// DiffFilesWithTolerance - Compare the two files specified, returning 0 if the |
| /// files match, 1 if they are different, and 2 if there is a file error. This |
| /// function differs from DiffFiles in that you can specify an absolute and |
| /// relative FP error that is allowed to exist. If you specify a string to fill |
| /// in for the error option, it will set the string to an error message if an |
| /// error occurs, allowing the caller to distinguish between a failed diff and a |
| /// file system error. |
| /// |
| int llvm::DiffFilesWithTolerance(StringRef NameA, |
| StringRef NameB, |
| double AbsTol, double RelTol, |
| std::string *Error) { |
| // Now its safe to mmap the files into memory because both files |
| // have a non-zero size. |
| ErrorOr<std::unique_ptr<MemoryBuffer>> F1OrErr = MemoryBuffer::getFile(NameA); |
| if (std::error_code EC = F1OrErr.getError()) { |
| if (Error) |
| *Error = EC.message(); |
| return 2; |
| } |
| MemoryBuffer &F1 = *F1OrErr.get(); |
| |
| ErrorOr<std::unique_ptr<MemoryBuffer>> F2OrErr = MemoryBuffer::getFile(NameB); |
| if (std::error_code EC = F2OrErr.getError()) { |
| if (Error) |
| *Error = EC.message(); |
| return 2; |
| } |
| MemoryBuffer &F2 = *F2OrErr.get(); |
| |
| // Okay, now that we opened the files, scan them for the first difference. |
| const char *File1Start = F1.getBufferStart(); |
| const char *File2Start = F2.getBufferStart(); |
| const char *File1End = F1.getBufferEnd(); |
| const char *File2End = F2.getBufferEnd(); |
| const char *F1P = File1Start; |
| const char *F2P = File2Start; |
| uint64_t A_size = F1.getBufferSize(); |
| uint64_t B_size = F2.getBufferSize(); |
| |
| // Are the buffers identical? Common case: Handle this efficiently. |
| if (A_size == B_size && |
| std::memcmp(File1Start, File2Start, A_size) == 0) |
| return 0; |
| |
| // Otherwise, we are done a tolerances are set. |
| if (AbsTol == 0 && RelTol == 0) { |
| if (Error) |
| *Error = "Files differ without tolerance allowance"; |
| return 1; // Files different! |
| } |
| |
| bool CompareFailed = false; |
| while (true) { |
| // Scan for the end of file or next difference. |
| while (F1P < File1End && F2P < File2End && *F1P == *F2P) { |
| ++F1P; |
| ++F2P; |
| } |
| |
| if (F1P >= File1End || F2P >= File2End) break; |
| |
| // Okay, we must have found a difference. Backup to the start of the |
| // current number each stream is at so that we can compare from the |
| // beginning. |
| F1P = BackupNumber(F1P, File1Start); |
| F2P = BackupNumber(F2P, File2Start); |
| |
| // Now that we are at the start of the numbers, compare them, exiting if |
| // they don't match. |
| if (CompareNumbers(F1P, F2P, File1End, File2End, AbsTol, RelTol, Error)) { |
| CompareFailed = true; |
| break; |
| } |
| } |
| |
| // Okay, we reached the end of file. If both files are at the end, we |
| // succeeded. |
| bool F1AtEnd = F1P >= File1End; |
| bool F2AtEnd = F2P >= File2End; |
| if (!CompareFailed && (!F1AtEnd || !F2AtEnd)) { |
| // Else, we might have run off the end due to a number: backup and retry. |
| if (F1AtEnd && isNumberChar(F1P[-1])) --F1P; |
| if (F2AtEnd && isNumberChar(F2P[-1])) --F2P; |
| F1P = BackupNumber(F1P, File1Start); |
| F2P = BackupNumber(F2P, File2Start); |
| |
| // Now that we are at the start of the numbers, compare them, exiting if |
| // they don't match. |
| if (CompareNumbers(F1P, F2P, File1End, File2End, AbsTol, RelTol, Error)) |
| CompareFailed = true; |
| |
| // If we found the end, we succeeded. |
| if (F1P < File1End || F2P < File2End) |
| CompareFailed = true; |
| } |
| |
| return CompareFailed; |
| } |
| |
| void llvm::AtomicFileWriteError::log(raw_ostream &OS) const { |
| OS << "atomic_write_error: "; |
| switch (Error) { |
| case atomic_write_error::failed_to_create_uniq_file: |
| OS << "failed_to_create_uniq_file"; |
| return; |
| case atomic_write_error::output_stream_error: |
| OS << "output_stream_error"; |
| return; |
| case atomic_write_error::failed_to_rename_temp_file: |
| OS << "failed_to_rename_temp_file"; |
| return; |
| } |
| llvm_unreachable("unknown atomic_write_error value in " |
| "failed_to_rename_temp_file::log()"); |
| } |
| |
| llvm::Error llvm::writeFileAtomically(StringRef TempPathModel, |
| StringRef FinalPath, StringRef Buffer) { |
| return writeFileAtomically(TempPathModel, FinalPath, |
| [&Buffer](llvm::raw_ostream &OS) { |
| OS.write(Buffer.data(), Buffer.size()); |
| return llvm::Error::success(); |
| }); |
| } |
| |
| llvm::Error llvm::writeFileAtomically( |
| StringRef TempPathModel, StringRef FinalPath, |
| std::function<llvm::Error(llvm::raw_ostream &)> Writer) { |
| SmallString<128> GeneratedUniqPath; |
| int TempFD; |
| if (sys::fs::createUniqueFile(TempPathModel, TempFD, GeneratedUniqPath)) { |
| return llvm::make_error<AtomicFileWriteError>( |
| atomic_write_error::failed_to_create_uniq_file); |
| } |
| llvm::FileRemover RemoveTmpFileOnFail(GeneratedUniqPath); |
| |
| raw_fd_ostream OS(TempFD, /*shouldClose=*/true); |
| if (llvm::Error Err = Writer(OS)) { |
| return Err; |
| } |
| |
| OS.close(); |
| if (OS.has_error()) { |
| OS.clear_error(); |
| return llvm::make_error<AtomicFileWriteError>( |
| atomic_write_error::output_stream_error); |
| } |
| |
| if (sys::fs::rename(/*from=*/GeneratedUniqPath, /*to=*/FinalPath)) { |
| return llvm::make_error<AtomicFileWriteError>( |
| atomic_write_error::failed_to_rename_temp_file); |
| } |
| |
| RemoveTmpFileOnFail.releaseFile(); |
| return Error::success(); |
| } |
| |
| Expected<FilePermissionsApplier> |
| FilePermissionsApplier::create(StringRef InputFilename) { |
| sys::fs::file_status Status; |
| |
| if (InputFilename != "-") { |
| if (auto EC = sys::fs::status(InputFilename, Status)) |
| return createFileError(InputFilename, EC); |
| } else { |
| Status.permissions(static_cast<sys::fs::perms>(0777)); |
| } |
| |
| return FilePermissionsApplier(InputFilename, Status); |
| } |
| |
| Error FilePermissionsApplier::apply( |
| StringRef OutputFilename, bool CopyDates, |
| std::optional<sys::fs::perms> OverwritePermissions) { |
| sys::fs::file_status Status = InputStatus; |
| |
| if (OverwritePermissions) |
| Status.permissions(*OverwritePermissions); |
| |
| int FD = 0; |
| |
| // Writing to stdout should not be treated as an error here, just |
| // do not set access/modification times or permissions. |
| if (OutputFilename == "-") |
| return Error::success(); |
| |
| if (std::error_code EC = sys::fs::openFileForWrite(OutputFilename, FD, |
| sys::fs::CD_OpenExisting)) |
| return createFileError(OutputFilename, EC); |
| |
| if (CopyDates) |
| if (std::error_code EC = sys::fs::setLastAccessAndModificationTime( |
| FD, Status.getLastAccessedTime(), Status.getLastModificationTime())) |
| return createFileError(OutputFilename, EC); |
| |
| sys::fs::file_status OStat; |
| if (std::error_code EC = sys::fs::status(FD, OStat)) |
| return createFileError(OutputFilename, EC); |
| if (OStat.type() == sys::fs::file_type::regular_file) { |
| #ifndef _WIN32 |
| // Keep ownership if llvm-objcopy is called under root. |
| if (OutputFilename == InputFilename && OStat.getUser() == 0) |
| sys::fs::changeFileOwnership(FD, Status.getUser(), Status.getGroup()); |
| #endif |
| |
| sys::fs::perms Perm = Status.permissions(); |
| if (OutputFilename != InputFilename) |
| Perm = static_cast<sys::fs::perms>(Perm & ~sys::fs::getUmask() & ~06000); |
| #ifdef _WIN32 |
| if (std::error_code EC = sys::fs::setPermissions(OutputFilename, Perm)) |
| #else |
| if (std::error_code EC = sys::fs::setPermissions(FD, Perm)) |
| #endif |
| return createFileError(OutputFilename, EC); |
| } |
| |
| if (std::error_code EC = sys::Process::SafelyCloseFileDescriptor(FD)) |
| return createFileError(OutputFilename, EC); |
| |
| return Error::success(); |
| } |
| |
| char llvm::AtomicFileWriteError::ID; |