llvm-6502/lib/Support/Unix/Path.inc
Michael J. Spencer 9170a0f02d Support/PathV1: Deprecate GetRootDirectory.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122580 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-27 03:21:41 +00:00

884 lines
23 KiB
C++

//===- llvm/Support/Unix/Path.cpp - 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 portion of the Path class.
//
//===----------------------------------------------------------------------===//
//===----------------------------------------------------------------------===//
//=== WARNING: Implementation here must contain only generic UNIX code that
//=== is guaranteed to work on *all* UNIX variants.
//===----------------------------------------------------------------------===//
#include "Unix.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
#ifdef HAVE_SYS_STAT_H
#include <sys/stat.h>
#endif
#if HAVE_UTIME_H
#include <utime.h>
#endif
#if HAVE_TIME_H
#include <time.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
#if HAVE_DLFCN_H
#include <dlfcn.h>
#endif
#ifdef __APPLE__
#include <mach-o/dyld.h>
#endif
// Put in a hack for Cygwin which falsely reports that the mkdtemp function
// is available when it is not.
#ifdef __CYGWIN__
# undef HAVE_MKDTEMP
#endif
namespace {
inline bool lastIsSlash(const std::string& path) {
return !path.empty() && path[path.length() - 1] == '/';
}
}
namespace llvm {
using namespace sys;
const char sys::PathSeparator = ':';
StringRef Path::GetEXESuffix() {
return StringRef();
}
Path::Path(StringRef p)
: path(p) {}
Path::Path(const char *StrStart, unsigned StrLen)
: path(StrStart, StrLen) {}
Path&
Path::operator=(StringRef that) {
path.assign(that.data(), that.size());
return *this;
}
bool
Path::isValid() const {
// Empty paths are considered invalid here.
// This code doesn't check MAXPATHLEN because there's no need. Nothing in
// LLVM manipulates Paths with fixed-sizes arrays, and if the OS can't
// handle names longer than some limit, it'll report this on demand using
// ENAMETOLONG.
return !path.empty();
}
bool
Path::isAbsolute(const char *NameStart, unsigned NameLen) {
assert(NameStart);
if (NameLen == 0)
return false;
return NameStart[0] == '/';
}
bool
Path::isAbsolute() const {
if (path.empty())
return false;
return path[0] == '/';
}
Path
Path::GetRootDirectory() {
Path result;
result.set("/");
return result;
}
Path
Path::GetTemporaryDirectory(std::string *ErrMsg) {
#if defined(HAVE_MKDTEMP)
// The best way is with mkdtemp but that's not available on many systems,
// Linux and FreeBSD have it. Others probably won't.
char pathname[] = "/tmp/llvm_XXXXXX";
if (0 == mkdtemp(pathname)) {
MakeErrMsg(ErrMsg,
std::string(pathname) + ": can't create temporary directory");
return Path();
}
return Path(pathname);
#elif defined(HAVE_MKSTEMP)
// If no mkdtemp is available, mkstemp can be used to create a temporary file
// which is then removed and created as a directory. We prefer this over
// mktemp because of mktemp's inherent security and threading risks. We still
// have a slight race condition from the time the temporary file is created to
// the time it is re-created as a directoy.
char pathname[] = "/tmp/llvm_XXXXXX";
int fd = 0;
if (-1 == (fd = mkstemp(pathname))) {
MakeErrMsg(ErrMsg,
std::string(pathname) + ": can't create temporary directory");
return Path();
}
::close(fd);
::unlink(pathname); // start race condition, ignore errors
if (-1 == ::mkdir(pathname, S_IRWXU)) { // end race condition
MakeErrMsg(ErrMsg,
std::string(pathname) + ": can't create temporary directory");
return Path();
}
return Path(pathname);
#elif defined(HAVE_MKTEMP)
// If a system doesn't have mkdtemp(3) or mkstemp(3) but it does have
// mktemp(3) then we'll assume that system (e.g. AIX) has a reasonable
// implementation of mktemp(3) and doesn't follow BSD 4.3's lead of replacing
// the XXXXXX with the pid of the process and a letter. That leads to only
// twenty six temporary files that can be generated.
char pathname[] = "/tmp/llvm_XXXXXX";
char *TmpName = ::mktemp(pathname);
if (TmpName == 0) {
MakeErrMsg(ErrMsg,
std::string(TmpName) + ": can't create unique directory name");
return Path();
}
if (-1 == ::mkdir(TmpName, S_IRWXU)) {
MakeErrMsg(ErrMsg,
std::string(TmpName) + ": can't create temporary directory");
return Path();
}
return Path(TmpName);
#else
// This is the worst case implementation. tempnam(3) leaks memory unless its
// on an SVID2 (or later) system. On BSD 4.3 it leaks. tmpnam(3) has thread
// issues. The mktemp(3) function doesn't have enough variability in the
// temporary name generated. So, we provide our own implementation that
// increments an integer from a random number seeded by the current time. This
// should be sufficiently unique that we don't have many collisions between
// processes. Generally LLVM processes don't run very long and don't use very
// many temporary files so this shouldn't be a big issue for LLVM.
static time_t num = ::time(0);
char pathname[MAXPATHLEN];
do {
num++;
sprintf(pathname, "/tmp/llvm_%010u", unsigned(num));
} while ( 0 == access(pathname, F_OK ) );
if (-1 == ::mkdir(pathname, S_IRWXU)) {
MakeErrMsg(ErrMsg,
std::string(pathname) + ": can't create temporary directory");
return Path();
}
return Path(pathname);
#endif
}
void
Path::GetSystemLibraryPaths(std::vector<sys::Path>& Paths) {
#ifdef LTDL_SHLIBPATH_VAR
char* env_var = getenv(LTDL_SHLIBPATH_VAR);
if (env_var != 0) {
getPathList(env_var,Paths);
}
#endif
// FIXME: Should this look at LD_LIBRARY_PATH too?
Paths.push_back(sys::Path("/usr/local/lib/"));
Paths.push_back(sys::Path("/usr/X11R6/lib/"));
Paths.push_back(sys::Path("/usr/lib/"));
Paths.push_back(sys::Path("/lib/"));
}
void
Path::GetBitcodeLibraryPaths(std::vector<sys::Path>& Paths) {
char * env_var = getenv("LLVM_LIB_SEARCH_PATH");
if (env_var != 0) {
getPathList(env_var,Paths);
}
#ifdef LLVM_LIBDIR
{
Path tmpPath;
if (tmpPath.set(LLVM_LIBDIR))
if (tmpPath.canRead())
Paths.push_back(tmpPath);
}
#endif
GetSystemLibraryPaths(Paths);
}
Path
Path::GetLLVMDefaultConfigDir() {
return Path("/etc/llvm/");
}
Path
Path::GetUserHomeDirectory() {
const char* home = getenv("HOME");
Path result;
if (home && result.set(home))
return result;
result.set("/");
return result;
}
Path
Path::GetCurrentDirectory() {
char pathname[MAXPATHLEN];
if (!getcwd(pathname,MAXPATHLEN)) {
assert (false && "Could not query current working directory.");
return Path();
}
return Path(pathname);
}
#if defined(__FreeBSD__) || defined (__NetBSD__) || defined(__minix)
static int
test_dir(char buf[PATH_MAX], char ret[PATH_MAX],
const char *dir, const char *bin)
{
struct stat sb;
snprintf(buf, PATH_MAX, "%s/%s", dir, bin);
if (realpath(buf, ret) == NULL)
return (1);
if (stat(buf, &sb) != 0)
return (1);
return (0);
}
static char *
getprogpath(char ret[PATH_MAX], const char *bin)
{
char *pv, *s, *t, buf[PATH_MAX];
/* First approach: absolute path. */
if (bin[0] == '/') {
if (test_dir(buf, ret, "/", bin) == 0)
return (ret);
return (NULL);
}
/* Second approach: relative path. */
if (strchr(bin, '/') != NULL) {
if (getcwd(buf, PATH_MAX) == NULL)
return (NULL);
if (test_dir(buf, ret, buf, 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(buf, ret, t, bin) == 0) {
free(pv);
return (ret);
}
}
free(pv);
return (NULL);
}
#endif // __FreeBSD__ || __NetBSD__
/// GetMainExecutable - Return the path to the main executable, given the
/// value of argv[0] from program startup.
Path Path::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 Path(link_path);
}
#elif defined(__FreeBSD__) || defined (__NetBSD__) || defined(__minix)
char exe_path[PATH_MAX];
if (getprogpath(exe_path, argv0) != NULL)
return Path(exe_path);
#elif defined(__linux__) || defined(__CYGWIN__)
char exe_path[MAXPATHLEN];
ssize_t len = readlink("/proc/self/exe", exe_path, sizeof(exe_path));
if (len >= 0)
return Path(StringRef(exe_path, len));
#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 Path();
// 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 Path(link_path);
#else
#error GetMainExecutable is not implemented on this host yet.
#endif
return Path();
}
StringRef Path::getDirname() const {
return getDirnameCharSep(path, "/");
}
StringRef
Path::getBasename() const {
// Find the last slash
std::string::size_type slash = path.rfind('/');
if (slash == std::string::npos)
slash = 0;
else
slash++;
std::string::size_type dot = path.rfind('.');
if (dot == std::string::npos || dot < slash)
return StringRef(path).substr(slash);
else
return StringRef(path).substr(slash, dot - slash);
}
StringRef
Path::getSuffix() const {
// Find the last slash
std::string::size_type slash = path.rfind('/');
if (slash == std::string::npos)
slash = 0;
else
slash++;
std::string::size_type dot = path.rfind('.');
if (dot == std::string::npos || dot < slash)
return StringRef();
else
return StringRef(path).substr(dot + 1);
}
bool Path::getMagicNumber(std::string &Magic, unsigned len) const {
assert(len < 1024 && "Request for magic string too long");
char Buf[1025];
int fd = ::open(path.c_str(), O_RDONLY);
if (fd < 0)
return false;
ssize_t bytes_read = ::read(fd, Buf, len);
::close(fd);
if (ssize_t(len) != bytes_read)
return false;
Magic.assign(Buf, len);
return true;
}
bool
Path::exists() const {
return 0 == access(path.c_str(), F_OK );
}
bool
Path::isDirectory() const {
struct stat buf;
if (0 != stat(path.c_str(), &buf))
return false;
return ((buf.st_mode & S_IFMT) == S_IFDIR) ? true : false;
}
bool
Path::isSymLink() const {
struct stat buf;
if (0 != lstat(path.c_str(), &buf))
return false;
return S_ISLNK(buf.st_mode);
}
bool
Path::canRead() const {
return 0 == access(path.c_str(), R_OK);
}
bool
Path::canWrite() const {
return 0 == access(path.c_str(), W_OK);
}
bool
Path::isRegularFile() const {
// Get the status so we can determine if it's a file or directory
struct stat buf;
if (0 != stat(path.c_str(), &buf))
return false;
if (S_ISREG(buf.st_mode))
return true;
return false;
}
bool
Path::canExecute() const {
if (0 != access(path.c_str(), R_OK | X_OK ))
return false;
struct stat buf;
if (0 != stat(path.c_str(), &buf))
return false;
if (!S_ISREG(buf.st_mode))
return false;
return true;
}
StringRef
Path::getLast() const {
// Find the last slash
size_t pos = path.rfind('/');
// Handle the corner cases
if (pos == std::string::npos)
return path;
// If the last character is a slash
if (pos == path.length()-1) {
// Find the second to last slash
size_t pos2 = path.rfind('/', pos-1);
if (pos2 == std::string::npos)
return StringRef(path).substr(0,pos);
else
return StringRef(path).substr(pos2+1,pos-pos2-1);
}
// Return everything after the last slash
return StringRef(path).substr(pos+1);
}
const FileStatus *
PathWithStatus::getFileStatus(bool update, std::string *ErrStr) const {
if (!fsIsValid || update) {
struct stat buf;
if (0 != stat(path.c_str(), &buf)) {
MakeErrMsg(ErrStr, path + ": can't get status of file");
return 0;
}
status.fileSize = buf.st_size;
status.modTime.fromEpochTime(buf.st_mtime);
status.mode = buf.st_mode;
status.user = buf.st_uid;
status.group = buf.st_gid;
status.uniqueID = uint64_t(buf.st_ino);
status.isDir = S_ISDIR(buf.st_mode);
status.isFile = S_ISREG(buf.st_mode);
fsIsValid = true;
}
return &status;
}
static bool AddPermissionBits(const Path &File, int bits) {
// Get the umask value from the operating system. We want to use it
// when changing the file's permissions. Since calling umask() sets
// the umask and returns its old value, we must call it a second
// time to reset it to the user's preference.
int mask = umask(0777); // The arg. to umask is arbitrary.
umask(mask); // Restore the umask.
// Get the file's current mode.
struct stat buf;
if (0 != stat(File.c_str(), &buf))
return false;
// Change the file to have whichever permissions bits from 'bits'
// that the umask would not disable.
if ((chmod(File.c_str(), (buf.st_mode | (bits & ~mask)))) == -1)
return false;
return true;
}
bool Path::makeReadableOnDisk(std::string* ErrMsg) {
if (!AddPermissionBits(*this, 0444))
return MakeErrMsg(ErrMsg, path + ": can't make file readable");
return false;
}
bool Path::makeWriteableOnDisk(std::string* ErrMsg) {
if (!AddPermissionBits(*this, 0222))
return MakeErrMsg(ErrMsg, path + ": can't make file writable");
return false;
}
bool Path::makeExecutableOnDisk(std::string* ErrMsg) {
if (!AddPermissionBits(*this, 0111))
return MakeErrMsg(ErrMsg, path + ": can't make file executable");
return false;
}
bool
Path::getDirectoryContents(std::set<Path>& result, std::string* ErrMsg) const {
DIR* direntries = ::opendir(path.c_str());
if (direntries == 0)
return MakeErrMsg(ErrMsg, path + ": can't open directory");
std::string dirPath = path;
if (!lastIsSlash(dirPath))
dirPath += '/';
result.clear();
struct dirent* de = ::readdir(direntries);
for ( ; de != 0; de = ::readdir(direntries)) {
if (de->d_name[0] != '.') {
Path aPath(dirPath + (const char*)de->d_name);
struct stat st;
if (0 != lstat(aPath.path.c_str(), &st)) {
if (S_ISLNK(st.st_mode))
continue; // dangling symlink -- ignore
return MakeErrMsg(ErrMsg,
aPath.path + ": can't determine file object type");
}
result.insert(aPath);
}
}
closedir(direntries);
return false;
}
bool
Path::set(StringRef a_path) {
if (a_path.empty())
return false;
path = a_path;
return true;
}
bool
Path::appendComponent(StringRef name) {
if (name.empty())
return false;
if (!lastIsSlash(path))
path += '/';
path += name;
return true;
}
bool
Path::eraseComponent() {
size_t slashpos = path.rfind('/',path.size());
if (slashpos == 0 || slashpos == std::string::npos) {
path.erase();
return true;
}
if (slashpos == path.size() - 1)
slashpos = path.rfind('/',slashpos-1);
if (slashpos == std::string::npos) {
path.erase();
return true;
}
path.erase(slashpos);
return true;
}
bool
Path::eraseSuffix() {
size_t dotpos = path.rfind('.',path.size());
size_t slashpos = path.rfind('/',path.size());
if (dotpos != std::string::npos) {
if (slashpos == std::string::npos || dotpos > slashpos+1) {
path.erase(dotpos, path.size()-dotpos);
return true;
}
}
return false;
}
static bool createDirectoryHelper(char* beg, char* end, bool create_parents) {
if (access(beg, R_OK | W_OK) == 0)
return false;
if (create_parents) {
char* c = end;
for (; c != beg; --c)
if (*c == '/') {
// Recurse to handling the parent directory.
*c = '\0';
bool x = createDirectoryHelper(beg, c, create_parents);
*c = '/';
// Return if we encountered an error.
if (x)
return true;
break;
}
}
return mkdir(beg, S_IRWXU | S_IRWXG) != 0;
}
bool
Path::createDirectoryOnDisk( bool create_parents, std::string* ErrMsg ) {
// Get a writeable copy of the path name
std::string pathname(path);
// Null-terminate the last component
size_t lastchar = path.length() - 1 ;
if (pathname[lastchar] != '/')
++lastchar;
pathname[lastchar] = '\0';
if (createDirectoryHelper(&pathname[0], &pathname[lastchar], create_parents))
return MakeErrMsg(ErrMsg, pathname + ": can't create directory");
return false;
}
bool
Path::createFileOnDisk(std::string* ErrMsg) {
// Create the file
int fd = ::creat(path.c_str(), S_IRUSR | S_IWUSR);
if (fd < 0)
return MakeErrMsg(ErrMsg, path + ": can't create file");
::close(fd);
return false;
}
bool
Path::createTemporaryFileOnDisk(bool reuse_current, std::string* ErrMsg) {
// Make this into a unique file name
if (makeUnique( reuse_current, ErrMsg ))
return true;
// create the file
int fd = ::open(path.c_str(), O_WRONLY|O_CREAT|O_TRUNC, 0666);
if (fd < 0)
return MakeErrMsg(ErrMsg, path + ": can't create temporary file");
::close(fd);
return false;
}
bool
Path::eraseFromDisk(bool remove_contents, std::string *ErrStr) const {
// Get the status so we can determine if it's a file or directory.
struct stat buf;
if (0 != stat(path.c_str(), &buf)) {
MakeErrMsg(ErrStr, path + ": can't get status of file");
return true;
}
// 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)) {
if (unlink(path.c_str()) != 0)
return MakeErrMsg(ErrStr, path + ": can't destroy file");
return false;
}
if (!S_ISDIR(buf.st_mode)) {
if (ErrStr) *ErrStr = "not a file or directory";
return true;
}
if (remove_contents) {
// Recursively descend the directory to remove its contents.
std::string cmd = "/bin/rm -rf " + path;
if (system(cmd.c_str()) != 0) {
MakeErrMsg(ErrStr, path + ": failed to recursively remove directory.");
return true;
}
return false;
}
// Otherwise, try to just remove the one directory.
std::string pathname(path);
size_t lastchar = path.length() - 1;
if (pathname[lastchar] == '/')
pathname[lastchar] = '\0';
else
pathname[lastchar+1] = '\0';
if (rmdir(pathname.c_str()) != 0)
return MakeErrMsg(ErrStr, pathname + ": can't erase directory");
return false;
}
bool
Path::renamePathOnDisk(const Path& newName, std::string* ErrMsg) {
if (0 != ::rename(path.c_str(), newName.c_str()))
return MakeErrMsg(ErrMsg, std::string("can't rename '") + path + "' as '" +
newName.str() + "'");
return false;
}
bool
Path::setStatusInfoOnDisk(const FileStatus &si, std::string *ErrStr) const {
struct utimbuf utb;
utb.actime = si.modTime.toPosixTime();
utb.modtime = utb.actime;
if (0 != ::utime(path.c_str(),&utb))
return MakeErrMsg(ErrStr, path + ": can't set file modification time");
if (0 != ::chmod(path.c_str(),si.mode))
return MakeErrMsg(ErrStr, path + ": can't set mode");
return false;
}
bool
sys::CopyFile(const sys::Path &Dest, const sys::Path &Src, std::string* ErrMsg){
int inFile = -1;
int outFile = -1;
inFile = ::open(Src.c_str(), O_RDONLY);
if (inFile == -1)
return MakeErrMsg(ErrMsg, Src.str() +
": can't open source file to copy");
outFile = ::open(Dest.c_str(), O_WRONLY|O_CREAT, 0666);
if (outFile == -1) {
::close(inFile);
return MakeErrMsg(ErrMsg, Dest.str() +
": can't create destination file for copy");
}
char Buffer[16*1024];
while (ssize_t Amt = ::read(inFile, Buffer, 16*1024)) {
if (Amt == -1) {
if (errno != EINTR && errno != EAGAIN) {
::close(inFile);
::close(outFile);
return MakeErrMsg(ErrMsg, Src.str()+": can't read source file");
}
} else {
char *BufPtr = Buffer;
while (Amt) {
ssize_t AmtWritten = ::write(outFile, BufPtr, Amt);
if (AmtWritten == -1) {
if (errno != EINTR && errno != EAGAIN) {
::close(inFile);
::close(outFile);
return MakeErrMsg(ErrMsg, Dest.str() +
": can't write destination file");
}
} else {
Amt -= AmtWritten;
BufPtr += AmtWritten;
}
}
}
}
::close(inFile);
::close(outFile);
return false;
}
bool
Path::makeUnique(bool reuse_current, std::string* ErrMsg) {
if (reuse_current && !exists())
return false; // File doesn't exist already, just use it!
// Append an XXXXXX pattern to the end of the file for use with mkstemp,
// mktemp or our own implementation.
// This uses std::vector instead of SmallVector to avoid a dependence on
// libSupport. And performance isn't critical here.
std::vector<char> Buf;
Buf.resize(path.size()+8);
char *FNBuffer = &Buf[0];
path.copy(FNBuffer,path.size());
if (isDirectory())
strcpy(FNBuffer+path.size(), "/XXXXXX");
else
strcpy(FNBuffer+path.size(), "-XXXXXX");
#if defined(HAVE_MKSTEMP)
int TempFD;
if ((TempFD = mkstemp(FNBuffer)) == -1)
return MakeErrMsg(ErrMsg, path + ": can't make unique filename");
// We don't need to hold the temp file descriptor... we will trust that no one
// will overwrite/delete the file before we can open it again.
close(TempFD);
// Save the name
path = FNBuffer;
#elif defined(HAVE_MKTEMP)
// If we don't have mkstemp, use the old and obsolete mktemp function.
if (mktemp(FNBuffer) == 0)
return MakeErrMsg(ErrMsg, path + ": can't make unique filename");
// Save the name
path = FNBuffer;
#else
// Okay, looks like we have to do it all by our lonesome.
static unsigned FCounter = 0;
// Try to initialize with unique value.
if (FCounter == 0) FCounter = ((unsigned)getpid() & 0xFFFF) << 8;
char* pos = strstr(FNBuffer, "XXXXXX");
do {
if (++FCounter > 0xFFFFFF) {
return MakeErrMsg(ErrMsg,
path + ": can't make unique filename: too many files");
}
sprintf(pos, "%06X", FCounter);
path = FNBuffer;
} while (exists());
// POSSIBLE SECURITY BUG: An attacker can easily guess the name and exploit
// LLVM.
#endif
return false;
}
const char *Path::MapInFilePages(int FD, uint64_t FileSize) {
int Flags = MAP_PRIVATE;
#ifdef MAP_FILE
Flags |= MAP_FILE;
#endif
void *BasePtr = ::mmap(0, FileSize, PROT_READ, Flags, FD, 0);
if (BasePtr == MAP_FAILED)
return 0;
return (const char*)BasePtr;
}
void Path::UnMapFilePages(const char *BasePtr, uint64_t FileSize) {
::munmap((void*)BasePtr, FileSize);
}
} // end llvm namespace