From 2bf7932f992575e4841656104a82403720902889 Mon Sep 17 00:00:00 2001 From: Rafael Espindola Date: Mon, 29 Jul 2013 21:26:49 +0000 Subject: [PATCH] Include st_dev to make the result of getUniqueID actually unique. This will let us use getUniqueID instead of st_dev directly on clang. llvm-svn: 187378 --- include/llvm/Support/FileSystem.h | 17 ++++++++++++++--- lib/Support/Path.cpp | 9 +++++++++ lib/Support/Unix/Path.inc | 16 ++++------------ lib/Support/Windows/Path.inc | 27 ++++++++------------------- unittests/Support/Path.cpp | 6 +++--- 5 files changed, 38 insertions(+), 37 deletions(-) diff --git a/include/llvm/Support/FileSystem.h b/include/llvm/Support/FileSystem.h index d4ca8397a57..908878f1b6e 100644 --- a/include/llvm/Support/FileSystem.h +++ b/include/llvm/Support/FileSystem.h @@ -125,8 +125,19 @@ inline perms operator~(perms x) { return static_cast(~static_cast(x)); } +class UniqueID { + uint64_t A; + uint64_t B; + +public: + UniqueID() {} + UniqueID(uint64_t A, uint64_t B) : A(A), B(B) {} + bool operator==(const UniqueID &Other) const { + return A == Other.A && B == Other.B; + } + bool operator!=(const UniqueID &Other) const { return !(*this == Other); } +}; - /// file_status - Represents the result of a call to stat and friends. It has /// a platform specific member to store the result. class file_status @@ -148,7 +159,6 @@ class file_status uint32_t FileIndexLow; #endif friend bool equivalent(file_status A, file_status B); - friend error_code getUniqueID(const Twine Path, uint64_t &Result); file_type Type; perms Perms; public: @@ -176,6 +186,7 @@ public: file_type type() const { return Type; } perms permissions() const { return Perms; } TimeValue getLastModificationTime() const; + UniqueID getUniqueID(); #if defined(LLVM_ON_UNIX) uint32_t getUser() const { return fs_st_uid; } @@ -664,7 +675,7 @@ file_magic identify_magic(StringRef magic); /// platform specific error_code. error_code identify_magic(const Twine &path, file_magic &result); -error_code getUniqueID(const Twine Path, uint64_t &Result); +error_code getUniqueID(const Twine Path, UniqueID &Result); /// This class represents a memory mapped file. It is based on /// boost::iostreams::mapped_file. diff --git a/lib/Support/Path.cpp b/lib/Support/Path.cpp index 6d10c0e67bb..cfd9ed6db3d 100644 --- a/lib/Support/Path.cpp +++ b/lib/Support/Path.cpp @@ -638,6 +638,15 @@ bool is_relative(const Twine &path) { namespace fs { +error_code getUniqueID(const Twine Path, UniqueID &Result) { + file_status Status; + error_code EC = status(Path, Status); + if (EC) + return EC; + Result = Status.getUniqueID(); + return error_code::success(); +} + error_code createUniqueFile(const Twine &Model, int &ResultFd, SmallVectorImpl &ResultPath, unsigned Mode) { return createUniqueEntity(Model, ResultFd, ResultPath, false, Mode, FS_File); diff --git a/lib/Support/Unix/Path.inc b/lib/Support/Unix/Path.inc index 5386366b542..0c4518c7493 100644 --- a/lib/Support/Unix/Path.inc +++ b/lib/Support/Unix/Path.inc @@ -293,6 +293,10 @@ TimeValue file_status::getLastModificationTime() const { return Ret; } +UniqueID file_status::getUniqueID() { + return UniqueID(fs_st_dev, fs_st_ino); +} + error_code current_path(SmallVectorImpl &result) { #ifdef MAXPATHLEN result.reserve(MAXPATHLEN); @@ -457,18 +461,6 @@ error_code equivalent(const Twine &A, const Twine &B, bool &result) { return error_code::success(); } -error_code getUniqueID(const Twine Path, uint64_t &Result) { - SmallString<128> Storage; - StringRef P = Path.toNullTerminatedStringRef(Storage); - - struct stat Status; - if (::stat(P.begin(), &Status) != 0) - return error_code(errno, system_category()); - - Result = Status.st_ino; - return error_code::success(); -} - static error_code fillStatus(int StatRet, const struct stat &Status, file_status &Result) { if (StatRet != 0) { diff --git a/lib/Support/Windows/Path.inc b/lib/Support/Windows/Path.inc index 99363431676..f3460e4c197 100644 --- a/lib/Support/Windows/Path.inc +++ b/lib/Support/Windows/Path.inc @@ -269,6 +269,14 @@ std::string getMainExecutable(const char *argv0, void *MainExecAddr) { return ret != MAX_PATH ? pathname : ""; } +UniqueID file_status::getUniqueID() { + // The file is uniquely identified by the volume serial number along + // with the 64-bit file identifier. + uint64_t FileID = (static_cast(FileIndexHigh) << 32ULL) | + static_cast(FileIndexLow); + + return UniqueID(VolumeSerialNumber, FileID); +} TimeValue file_status::getLastModificationTime() const { ULARGE_INTEGER UI; @@ -533,25 +541,6 @@ error_code equivalent(const Twine &A, const Twine &B, bool &result) { return error_code::success(); } -error_code getUniqueID(const Twine Path, uint64_t &Result) { - file_status Status; - if (error_code E = status(Path, Status)) - return E; - - // The file is uniquely identified by the volume serial number along - // with the 64-bit file identifier. - Result = (static_cast(Status.FileIndexHigh) << 32ULL) | - static_cast(Status.FileIndexLow); - - // Because the serial number is 32-bits, but we've already used up all 64 - // bits for the file index, XOR the serial number into the high 32 bits of - // the resulting value. We could potentially get collisons from this, but - // the likelihood is low. - Result ^= (static_cast(Status.VolumeSerialNumber) << 32ULL); - - return error_code::success(); -} - static bool isReservedName(StringRef path) { // This list of reserved names comes from MSDN, at: // http://msdn.microsoft.com/en-us/library/aa365247%28v=vs.85%29.aspx diff --git a/unittests/Support/Path.cpp b/unittests/Support/Path.cpp index 2f19bb29442..165668d61b5 100644 --- a/unittests/Support/Path.cpp +++ b/unittests/Support/Path.cpp @@ -169,7 +169,7 @@ TEST_F(FileSystemTest, Unique) { fs::createTemporaryFile("prefix", "temp", FileDescriptor, TempPath)); // The same file should return an identical unique id. - uint64_t F1, F2; + fs::UniqueID F1, F2; ASSERT_NO_ERROR(fs::getUniqueID(Twine(TempPath), F1)); ASSERT_NO_ERROR(fs::getUniqueID(Twine(TempPath), F2)); ASSERT_EQ(F1, F2); @@ -180,7 +180,7 @@ TEST_F(FileSystemTest, Unique) { ASSERT_NO_ERROR( fs::createTemporaryFile("prefix", "temp", FileDescriptor2, TempPath2)); - uint64_t D; + fs::UniqueID D; ASSERT_NO_ERROR(fs::getUniqueID(Twine(TempPath2), D)); ASSERT_NE(D, F1); ::close(FileDescriptor2); @@ -190,7 +190,7 @@ TEST_F(FileSystemTest, Unique) { // Two paths representing the same file on disk should still provide the // same unique id. We can test this by making a hard link. ASSERT_NO_ERROR(fs::create_hard_link(Twine(TempPath), Twine(TempPath2))); - uint64_t D2; + fs::UniqueID D2; ASSERT_NO_ERROR(fs::getUniqueID(Twine(TempPath2), D2)); ASSERT_EQ(D2, F1);