path: root/lib/Support/Unix/Path.inc

//===- 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

// For GNU Hurd
#if defined(__GNU__) && !defined(MAXPATHLEN)
# define MAXPATHLEN 4096
#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(__native_client__)
  return Path("");
#elif 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