llvm-6502/lib/Support/Unix/Path.inc
Peter Collingbourne bef2236283 Introduce llvm::sys::path::home_directory.
This will be used by the line editor library to derive a default path to
the history file.

Differential Revision: http://llvm-reviews.chandlerc.com/D2199

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200594 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-31 23:46:06 +00:00

817 lines
23 KiB
C++

//===- llvm/Support/Unix/Path.inc - Unix Path Implementation ----*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the Unix specific implementation of the Path API.
//
//===----------------------------------------------------------------------===//
//===----------------------------------------------------------------------===//
//=== WARNING: Implementation here must contain only generic UNIX code that
//=== is guaranteed to work on *all* UNIX variants.
//===----------------------------------------------------------------------===//
#include "Unix.h"
#include "llvm/Support/Process.h"
#include <limits.h>
#include <stdio.h>
#if HAVE_SYS_STAT_H
#include <sys/stat.h>
#endif
#if HAVE_FCNTL_H
#include <fcntl.h>
#endif
#ifdef HAVE_SYS_MMAN_H
#include <sys/mman.h>
#endif
#if HAVE_DIRENT_H
# include <dirent.h>
# define NAMLEN(dirent) strlen((dirent)->d_name)
#else
# define dirent direct
# define NAMLEN(dirent) (dirent)->d_namlen
# if HAVE_SYS_NDIR_H
# include <sys/ndir.h>
# endif
# if HAVE_SYS_DIR_H
# include <sys/dir.h>
# endif
# if HAVE_NDIR_H
# include <ndir.h>
# endif
#endif
#ifdef __APPLE__
#include <mach-o/dyld.h>
#endif
// Both stdio.h and cstdio are included via different pathes and
// stdcxx's cstdio doesn't include stdio.h, so it doesn't #undef the macros
// either.
#undef ferror
#undef feof
// For GNU Hurd
#if defined(__GNU__) && !defined(PATH_MAX)
# define PATH_MAX 4096
#endif
using namespace llvm;
namespace {
/// This class automatically closes the given file descriptor when it goes out
/// of scope. You can take back explicit ownership of the file descriptor by
/// calling take(). The destructor does not verify that close was successful.
/// Therefore, never allow this class to call close on a file descriptor that
/// has been read from or written to.
struct AutoFD {
int FileDescriptor;
AutoFD(int fd) : FileDescriptor(fd) {}
~AutoFD() {
if (FileDescriptor >= 0)
::close(FileDescriptor);
}
int take() {
int ret = FileDescriptor;
FileDescriptor = -1;
return ret;
}
operator int() const {return FileDescriptor;}
};
error_code TempDir(SmallVectorImpl<char> &result) {
// FIXME: Don't use TMPDIR if program is SUID or SGID enabled.
const char *dir = 0;
(dir = std::getenv("TMPDIR" )) ||
(dir = std::getenv("TMP" )) ||
(dir = std::getenv("TEMP" )) ||
(dir = std::getenv("TEMPDIR")) ||
#ifdef P_tmpdir
(dir = P_tmpdir) ||
#endif
(dir = "/tmp");
result.clear();
StringRef d(dir);
result.append(d.begin(), d.end());
return error_code::success();
}
}
static error_code createUniqueEntity(const Twine &Model, int &ResultFD,
SmallVectorImpl<char> &ResultPath,
bool MakeAbsolute, unsigned Mode,
FSEntity Type) {
SmallString<128> ModelStorage;
Model.toVector(ModelStorage);
if (MakeAbsolute) {
// Make model absolute by prepending a temp directory if it's not already.
bool absolute = sys::path::is_absolute(Twine(ModelStorage));
if (!absolute) {
SmallString<128> TDir;
if (error_code ec = TempDir(TDir)) return ec;
sys::path::append(TDir, Twine(ModelStorage));
ModelStorage.swap(TDir);
}
}
// From here on, DO NOT modify model. It may be needed if the randomly chosen
// path already exists.
ResultPath = ModelStorage;
// Null terminate.
ResultPath.push_back(0);
ResultPath.pop_back();
retry_random_path:
// Replace '%' with random chars.
for (unsigned i = 0, e = ModelStorage.size(); i != e; ++i) {
if (ModelStorage[i] == '%')
ResultPath[i] = "0123456789abcdef"[sys::Process::GetRandomNumber() & 15];
}
// Try to open + create the file.
switch (Type) {
case FS_File: {
int RandomFD = ::open(ResultPath.begin(), O_RDWR | O_CREAT | O_EXCL, Mode);
if (RandomFD == -1) {
int SavedErrno = errno;
// If the file existed, try again, otherwise, error.
if (SavedErrno == errc::file_exists)
goto retry_random_path;
return error_code(SavedErrno, system_category());
}
ResultFD = RandomFD;
return error_code::success();
}
case FS_Name: {
bool Exists;
error_code EC = sys::fs::exists(ResultPath.begin(), Exists);
if (EC)
return EC;
if (Exists)
goto retry_random_path;
return error_code::success();
}
case FS_Dir: {
bool Existed;
error_code EC = sys::fs::create_directory(ResultPath.begin(), Existed);
if (EC)
return EC;
if (Existed)
goto retry_random_path;
return error_code::success();
}
}
llvm_unreachable("Invalid Type");
}
namespace llvm {
namespace sys {
namespace fs {
#if defined(__FreeBSD__) || defined (__NetBSD__) || defined(__Bitrig__) || \
defined(__OpenBSD__) || defined(__minix) || defined(__FreeBSD_kernel__) || \
defined(__linux__) || defined(__CYGWIN__) || defined(__DragonFly__)
static int
test_dir(char ret[PATH_MAX], const char *dir, const char *bin)
{
struct stat sb;
char fullpath[PATH_MAX];
snprintf(fullpath, PATH_MAX, "%s/%s", dir, bin);
if (realpath(fullpath, ret) == NULL)
return (1);
if (stat(fullpath, &sb) != 0)
return (1);
return (0);
}
static char *
getprogpath(char ret[PATH_MAX], const char *bin)
{
char *pv, *s, *t;
/* First approach: absolute path. */
if (bin[0] == '/') {
if (test_dir(ret, "/", bin) == 0)
return (ret);
return (NULL);
}
/* Second approach: relative path. */
if (strchr(bin, '/') != NULL) {
char cwd[PATH_MAX];
if (getcwd(cwd, PATH_MAX) == NULL)
return (NULL);
if (test_dir(ret, cwd, bin) == 0)
return (ret);
return (NULL);
}
/* Third approach: $PATH */
if ((pv = getenv("PATH")) == NULL)
return (NULL);
s = pv = strdup(pv);
if (pv == NULL)
return (NULL);
while ((t = strsep(&s, ":")) != NULL) {
if (test_dir(ret, t, bin) == 0) {
free(pv);
return (ret);
}
}
free(pv);
return (NULL);
}
#endif // __FreeBSD__ || __NetBSD__ || __FreeBSD_kernel__
/// GetMainExecutable - Return the path to the main executable, given the
/// value of argv[0] from program startup.
std::string getMainExecutable(const char *argv0, void *MainAddr) {
#if defined(__APPLE__)
// On OS X the executable path is saved to the stack by dyld. Reading it
// from there is much faster than calling dladdr, especially for large
// binaries with symbols.
char exe_path[MAXPATHLEN];
uint32_t size = sizeof(exe_path);
if (_NSGetExecutablePath(exe_path, &size) == 0) {
char link_path[MAXPATHLEN];
if (realpath(exe_path, link_path))
return link_path;
}
#elif defined(__FreeBSD__) || defined (__NetBSD__) || defined(__Bitrig__) || \
defined(__OpenBSD__) || defined(__minix) || defined(__DragonFly__) || \
defined(__FreeBSD_kernel__)
char exe_path[PATH_MAX];
if (getprogpath(exe_path, argv0) != NULL)
return exe_path;
#elif defined(__linux__) || defined(__CYGWIN__)
char exe_path[MAXPATHLEN];
StringRef aPath("/proc/self/exe");
if (sys::fs::exists(aPath)) {
// /proc is not always mounted under Linux (chroot for example).
ssize_t len = readlink(aPath.str().c_str(), exe_path, sizeof(exe_path));
if (len >= 0)
return StringRef(exe_path, len);
} else {
// Fall back to the classical detection.
if (getprogpath(exe_path, argv0) != NULL)
return exe_path;
}
#elif defined(HAVE_DLFCN_H)
// Use dladdr to get executable path if available.
Dl_info DLInfo;
int err = dladdr(MainAddr, &DLInfo);
if (err == 0)
return "";
// If the filename is a symlink, we need to resolve and return the location of
// the actual executable.
char link_path[MAXPATHLEN];
if (realpath(DLInfo.dli_fname, link_path))
return link_path;
#else
#error GetMainExecutable is not implemented on this host yet.
#endif
return "";
}
TimeValue file_status::getLastModificationTime() const {
TimeValue Ret;
Ret.fromEpochTime(fs_st_mtime);
return Ret;
}
UniqueID file_status::getUniqueID() const {
return UniqueID(fs_st_dev, fs_st_ino);
}
error_code current_path(SmallVectorImpl<char> &result) {
result.clear();
const char *pwd = ::getenv("PWD");
llvm::sys::fs::file_status PWDStatus, DotStatus;
if (pwd && llvm::sys::path::is_absolute(pwd) &&
!llvm::sys::fs::status(pwd, PWDStatus) &&
!llvm::sys::fs::status(".", DotStatus) &&
PWDStatus.getUniqueID() == DotStatus.getUniqueID()) {
result.append(pwd, pwd + strlen(pwd));
return error_code::success();
}
#ifdef MAXPATHLEN
result.reserve(MAXPATHLEN);
#else
// For GNU Hurd
result.reserve(1024);
#endif
while (true) {
if (::getcwd(result.data(), result.capacity()) == 0) {
// See if there was a real error.
if (errno != errc::not_enough_memory)
return error_code(errno, system_category());
// Otherwise there just wasn't enough space.
result.reserve(result.capacity() * 2);
} else
break;
}
result.set_size(strlen(result.data()));
return error_code::success();
}
error_code create_directory(const Twine &path, bool &existed) {
SmallString<128> path_storage;
StringRef p = path.toNullTerminatedStringRef(path_storage);
if (::mkdir(p.begin(), S_IRWXU | S_IRWXG) == -1) {
if (errno != errc::file_exists)
return error_code(errno, system_category());
existed = true;
} else
existed = false;
return error_code::success();
}
error_code create_hard_link(const Twine &to, const Twine &from) {
// Get arguments.
SmallString<128> from_storage;
SmallString<128> to_storage;
StringRef f = from.toNullTerminatedStringRef(from_storage);
StringRef t = to.toNullTerminatedStringRef(to_storage);
if (::link(t.begin(), f.begin()) == -1)
return error_code(errno, system_category());
return error_code::success();
}
error_code create_symlink(const Twine &to, const Twine &from) {
// Get arguments.
SmallString<128> from_storage;
SmallString<128> to_storage;
StringRef f = from.toNullTerminatedStringRef(from_storage);
StringRef t = to.toNullTerminatedStringRef(to_storage);
if (::symlink(t.begin(), f.begin()) == -1)
return error_code(errno, system_category());
return error_code::success();
}
error_code remove(const Twine &path, bool &existed) {
SmallString<128> path_storage;
StringRef p = path.toNullTerminatedStringRef(path_storage);
struct stat buf;
if (stat(p.begin(), &buf) != 0) {
if (errno != errc::no_such_file_or_directory)
return error_code(errno, system_category());
existed = false;
return error_code::success();
}
// Note: this check catches strange situations. In all cases, LLVM should
// only be involved in the creation and deletion of regular files. This
// check ensures that what we're trying to erase is a regular file. It
// effectively prevents LLVM from erasing things like /dev/null, any block
// special file, or other things that aren't "regular" files.
if (!S_ISREG(buf.st_mode) && !S_ISDIR(buf.st_mode))
return make_error_code(errc::operation_not_permitted);
if (::remove(p.begin()) == -1) {
if (errno != errc::no_such_file_or_directory)
return error_code(errno, system_category());
existed = false;
} else
existed = true;
return error_code::success();
}
error_code rename(const Twine &from, const Twine &to) {
// Get arguments.
SmallString<128> from_storage;
SmallString<128> to_storage;
StringRef f = from.toNullTerminatedStringRef(from_storage);
StringRef t = to.toNullTerminatedStringRef(to_storage);
if (::rename(f.begin(), t.begin()) == -1)
return error_code(errno, system_category());
return error_code::success();
}
error_code resize_file(const Twine &path, uint64_t size) {
SmallString<128> path_storage;
StringRef p = path.toNullTerminatedStringRef(path_storage);
if (::truncate(p.begin(), size) == -1)
return error_code(errno, system_category());
return error_code::success();
}
error_code exists(const Twine &path, bool &result) {
SmallString<128> path_storage;
StringRef p = path.toNullTerminatedStringRef(path_storage);
if (::access(p.begin(), F_OK) == -1) {
if (errno != errc::no_such_file_or_directory)
return error_code(errno, system_category());
result = false;
} else
result = true;
return error_code::success();
}
bool can_write(const Twine &Path) {
SmallString<128> PathStorage;
StringRef P = Path.toNullTerminatedStringRef(PathStorage);
return 0 == access(P.begin(), W_OK);
}
bool can_execute(const Twine &Path) {
SmallString<128> PathStorage;
StringRef P = Path.toNullTerminatedStringRef(PathStorage);
if (0 != access(P.begin(), R_OK | X_OK))
return false;
struct stat buf;
if (0 != stat(P.begin(), &buf))
return false;
if (!S_ISREG(buf.st_mode))
return false;
return true;
}
bool equivalent(file_status A, file_status B) {
assert(status_known(A) && status_known(B));
return A.fs_st_dev == B.fs_st_dev &&
A.fs_st_ino == B.fs_st_ino;
}
error_code equivalent(const Twine &A, const Twine &B, bool &result) {
file_status fsA, fsB;
if (error_code ec = status(A, fsA)) return ec;
if (error_code ec = status(B, fsB)) return ec;
result = equivalent(fsA, fsB);
return error_code::success();
}
static error_code fillStatus(int StatRet, const struct stat &Status,
file_status &Result) {
if (StatRet != 0) {
error_code ec(errno, system_category());
if (ec == errc::no_such_file_or_directory)
Result = file_status(file_type::file_not_found);
else
Result = file_status(file_type::status_error);
return ec;
}
file_type Type = file_type::type_unknown;
if (S_ISDIR(Status.st_mode))
Type = file_type::directory_file;
else if (S_ISREG(Status.st_mode))
Type = file_type::regular_file;
else if (S_ISBLK(Status.st_mode))
Type = file_type::block_file;
else if (S_ISCHR(Status.st_mode))
Type = file_type::character_file;
else if (S_ISFIFO(Status.st_mode))
Type = file_type::fifo_file;
else if (S_ISSOCK(Status.st_mode))
Type = file_type::socket_file;
perms Perms = static_cast<perms>(Status.st_mode);
Result =
file_status(Type, Perms, Status.st_dev, Status.st_ino, Status.st_mtime,
Status.st_uid, Status.st_gid, Status.st_size);
return error_code::success();
}
error_code status(const Twine &Path, file_status &Result) {
SmallString<128> PathStorage;
StringRef P = Path.toNullTerminatedStringRef(PathStorage);
struct stat Status;
int StatRet = ::stat(P.begin(), &Status);
return fillStatus(StatRet, Status, Result);
}
error_code status(int FD, file_status &Result) {
struct stat Status;
int StatRet = ::fstat(FD, &Status);
return fillStatus(StatRet, Status, Result);
}
error_code setLastModificationAndAccessTime(int FD, TimeValue Time) {
#if defined(HAVE_FUTIMENS)
timespec Times[2];
Times[0].tv_sec = Time.toPosixTime();
Times[0].tv_nsec = 0;
Times[1] = Times[0];
if (::futimens(FD, Times))
return error_code(errno, system_category());
return error_code::success();
#elif defined(HAVE_FUTIMES)
timeval Times[2];
Times[0].tv_sec = Time.toPosixTime();
Times[0].tv_usec = 0;
Times[1] = Times[0];
if (::futimes(FD, Times))
return error_code(errno, system_category());
return error_code::success();
#else
#warning Missing futimes() and futimens()
return make_error_code(errc::not_supported);
#endif
}
error_code mapped_file_region::init(int FD, bool CloseFD, uint64_t Offset) {
AutoFD ScopedFD(FD);
if (!CloseFD)
ScopedFD.take();
// Figure out how large the file is.
struct stat FileInfo;
if (fstat(FD, &FileInfo) == -1)
return error_code(errno, system_category());
uint64_t FileSize = FileInfo.st_size;
if (Size == 0)
Size = FileSize;
else if (FileSize < Size) {
// We need to grow the file.
if (ftruncate(FD, Size) == -1)
return error_code(errno, system_category());
}
int flags = (Mode == readwrite) ? MAP_SHARED : MAP_PRIVATE;
int prot = (Mode == readonly) ? PROT_READ : (PROT_READ | PROT_WRITE);
#ifdef MAP_FILE
flags |= MAP_FILE;
#endif
Mapping = ::mmap(0, Size, prot, flags, FD, Offset);
if (Mapping == MAP_FAILED)
return error_code(errno, system_category());
return error_code::success();
}
mapped_file_region::mapped_file_region(const Twine &path,
mapmode mode,
uint64_t length,
uint64_t offset,
error_code &ec)
: Mode(mode)
, Size(length)
, Mapping() {
// Make sure that the requested size fits within SIZE_T.
if (length > std::numeric_limits<size_t>::max()) {
ec = make_error_code(errc::invalid_argument);
return;
}
SmallString<128> path_storage;
StringRef name = path.toNullTerminatedStringRef(path_storage);
int oflags = (mode == readonly) ? O_RDONLY : O_RDWR;
int ofd = ::open(name.begin(), oflags);
if (ofd == -1) {
ec = error_code(errno, system_category());
return;
}
ec = init(ofd, true, offset);
if (ec)
Mapping = 0;
}
mapped_file_region::mapped_file_region(int fd,
bool closefd,
mapmode mode,
uint64_t length,
uint64_t offset,
error_code &ec)
: Mode(mode)
, Size(length)
, Mapping() {
// Make sure that the requested size fits within SIZE_T.
if (length > std::numeric_limits<size_t>::max()) {
ec = make_error_code(errc::invalid_argument);
return;
}
ec = init(fd, closefd, offset);
if (ec)
Mapping = 0;
}
mapped_file_region::~mapped_file_region() {
if (Mapping)
::munmap(Mapping, Size);
}
#if LLVM_HAS_RVALUE_REFERENCES
mapped_file_region::mapped_file_region(mapped_file_region &&other)
: Mode(other.Mode), Size(other.Size), Mapping(other.Mapping) {
other.Mapping = 0;
}
#endif
mapped_file_region::mapmode mapped_file_region::flags() const {
assert(Mapping && "Mapping failed but used anyway!");
return Mode;
}
uint64_t mapped_file_region::size() const {
assert(Mapping && "Mapping failed but used anyway!");
return Size;
}
char *mapped_file_region::data() const {
assert(Mapping && "Mapping failed but used anyway!");
assert(Mode != readonly && "Cannot get non-const data for readonly mapping!");
return reinterpret_cast<char*>(Mapping);
}
const char *mapped_file_region::const_data() const {
assert(Mapping && "Mapping failed but used anyway!");
return reinterpret_cast<const char*>(Mapping);
}
int mapped_file_region::alignment() {
return process::get_self()->page_size();
}
error_code detail::directory_iterator_construct(detail::DirIterState &it,
StringRef path){
SmallString<128> path_null(path);
DIR *directory = ::opendir(path_null.c_str());
if (directory == 0)
return error_code(errno, system_category());
it.IterationHandle = reinterpret_cast<intptr_t>(directory);
// Add something for replace_filename to replace.
path::append(path_null, ".");
it.CurrentEntry = directory_entry(path_null.str());
return directory_iterator_increment(it);
}
error_code detail::directory_iterator_destruct(detail::DirIterState &it) {
if (it.IterationHandle)
::closedir(reinterpret_cast<DIR *>(it.IterationHandle));
it.IterationHandle = 0;
it.CurrentEntry = directory_entry();
return error_code::success();
}
error_code detail::directory_iterator_increment(detail::DirIterState &it) {
errno = 0;
dirent *cur_dir = ::readdir(reinterpret_cast<DIR *>(it.IterationHandle));
if (cur_dir == 0 && errno != 0) {
return error_code(errno, system_category());
} else if (cur_dir != 0) {
StringRef name(cur_dir->d_name, NAMLEN(cur_dir));
if ((name.size() == 1 && name[0] == '.') ||
(name.size() == 2 && name[0] == '.' && name[1] == '.'))
return directory_iterator_increment(it);
it.CurrentEntry.replace_filename(name);
} else
return directory_iterator_destruct(it);
return error_code::success();
}
error_code get_magic(const Twine &path, uint32_t len,
SmallVectorImpl<char> &result) {
SmallString<128> PathStorage;
StringRef Path = path.toNullTerminatedStringRef(PathStorage);
result.set_size(0);
// Open path.
std::FILE *file = std::fopen(Path.data(), "rb");
if (file == 0)
return error_code(errno, system_category());
// Reserve storage.
result.reserve(len);
// Read magic!
size_t size = std::fread(result.data(), 1, len, file);
if (std::ferror(file) != 0) {
std::fclose(file);
return error_code(errno, system_category());
} else if (size != len) {
if (std::feof(file) != 0) {
std::fclose(file);
result.set_size(size);
return make_error_code(errc::value_too_large);
}
}
std::fclose(file);
result.set_size(size);
return error_code::success();
}
error_code map_file_pages(const Twine &path, off_t file_offset, size_t size,
bool map_writable, void *&result) {
SmallString<128> path_storage;
StringRef name = path.toNullTerminatedStringRef(path_storage);
int oflags = map_writable ? O_RDWR : O_RDONLY;
int ofd = ::open(name.begin(), oflags);
if ( ofd == -1 )
return error_code(errno, system_category());
AutoFD fd(ofd);
int flags = map_writable ? MAP_SHARED : MAP_PRIVATE;
int prot = map_writable ? (PROT_READ|PROT_WRITE) : PROT_READ;
#ifdef MAP_FILE
flags |= MAP_FILE;
#endif
result = ::mmap(0, size, prot, flags, fd, file_offset);
if (result == MAP_FAILED) {
return error_code(errno, system_category());
}
return error_code::success();
}
error_code unmap_file_pages(void *base, size_t size) {
if ( ::munmap(base, size) == -1 )
return error_code(errno, system_category());
return error_code::success();
}
error_code openFileForRead(const Twine &Name, int &ResultFD) {
SmallString<128> Storage;
StringRef P = Name.toNullTerminatedStringRef(Storage);
while ((ResultFD = open(P.begin(), O_RDONLY)) < 0) {
if (errno != EINTR)
return error_code(errno, system_category());
}
return error_code::success();
}
error_code openFileForWrite(const Twine &Name, int &ResultFD,
sys::fs::OpenFlags Flags, unsigned Mode) {
// Verify that we don't have both "append" and "excl".
assert((!(Flags & sys::fs::F_Excl) || !(Flags & sys::fs::F_Append)) &&
"Cannot specify both 'excl' and 'append' file creation flags!");
int OpenFlags = O_WRONLY | O_CREAT;
if (Flags & F_Append)
OpenFlags |= O_APPEND;
else
OpenFlags |= O_TRUNC;
if (Flags & F_Excl)
OpenFlags |= O_EXCL;
SmallString<128> Storage;
StringRef P = Name.toNullTerminatedStringRef(Storage);
while ((ResultFD = open(P.begin(), OpenFlags, Mode)) < 0) {
if (errno != EINTR)
return error_code(errno, system_category());
}
return error_code::success();
}
} // end namespace fs
namespace path {
bool home_directory(SmallVectorImpl<char> &result) {
if (char *RequestedDir = getenv("HOME")) {
result.clear();
result.append(RequestedDir, RequestedDir + strlen(RequestedDir));
return true;
}
return false;
}
} // end namespace path
} // end namespace sys
} // end namespace llvm