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Diffstat (limited to 'contrib/llvm/lib/Support/Path.cpp')
| -rw-r--r-- | contrib/llvm/lib/Support/Path.cpp | 1089 | 
1 files changed, 1089 insertions, 0 deletions
| diff --git a/contrib/llvm/lib/Support/Path.cpp b/contrib/llvm/lib/Support/Path.cpp new file mode 100644 index 000000000000..d5a0ec55c682 --- /dev/null +++ b/contrib/llvm/lib/Support/Path.cpp @@ -0,0 +1,1089 @@ +//===-- Path.cpp - Implement OS Path Concept ------------------------------===// +// +//                     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 operating system Path API. +// +//===----------------------------------------------------------------------===// + +#include "llvm/Support/Errc.h" +#include "llvm/Support/Path.h" +#include "llvm/Support/Endian.h" +#include "llvm/Support/ErrorHandling.h" +#include "llvm/Support/FileSystem.h" +#include "llvm/Support/Process.h" +#include <cctype> +#include <cstdio> +#include <cstring> +#include <fcntl.h> + +#if !defined(_MSC_VER) && !defined(__MINGW32__) +#include <unistd.h> +#else +#include <io.h> +#endif + +using namespace llvm; + +namespace { +  using llvm::StringRef; +  using llvm::sys::path::is_separator; + +#ifdef LLVM_ON_WIN32 +  const char *separators = "\\/"; +  const char preferred_separator = '\\'; +#else +  const char  separators = '/'; +  const char preferred_separator = '/'; +#endif + +  StringRef find_first_component(StringRef path) { +    // Look for this first component in the following order. +    // * empty (in this case we return an empty string) +    // * either C: or {//,\\}net. +    // * {/,\} +    // * {.,..} +    // * {file,directory}name + +    if (path.empty()) +      return path; + +#ifdef LLVM_ON_WIN32 +    // C: +    if (path.size() >= 2 && std::isalpha(static_cast<unsigned char>(path[0])) && +        path[1] == ':') +      return path.substr(0, 2); +#endif + +    // //net +    if ((path.size() > 2) && +        is_separator(path[0]) && +        path[0] == path[1] && +        !is_separator(path[2])) { +      // Find the next directory separator. +      size_t end = path.find_first_of(separators, 2); +      return path.substr(0, end); +    } + +    // {/,\} +    if (is_separator(path[0])) +      return path.substr(0, 1); + +    if (path.startswith("..")) +      return path.substr(0, 2); + +    if (path[0] == '.') +      return path.substr(0, 1); + +    // * {file,directory}name +    size_t end = path.find_first_of(separators); +    return path.substr(0, end); +  } + +  size_t filename_pos(StringRef str) { +    if (str.size() == 2 && +        is_separator(str[0]) && +        str[0] == str[1]) +      return 0; + +    if (str.size() > 0 && is_separator(str[str.size() - 1])) +      return str.size() - 1; + +    size_t pos = str.find_last_of(separators, str.size() - 1); + +#ifdef LLVM_ON_WIN32 +    if (pos == StringRef::npos) +      pos = str.find_last_of(':', str.size() - 2); +#endif + +    if (pos == StringRef::npos || +        (pos == 1 && is_separator(str[0]))) +      return 0; + +    return pos + 1; +  } + +  size_t root_dir_start(StringRef str) { +    // case "c:/" +#ifdef LLVM_ON_WIN32 +    if (str.size() > 2 && +        str[1] == ':' && +        is_separator(str[2])) +      return 2; +#endif + +    // case "//" +    if (str.size() == 2 && +        is_separator(str[0]) && +        str[0] == str[1]) +      return StringRef::npos; + +    // case "//net" +    if (str.size() > 3 && +        is_separator(str[0]) && +        str[0] == str[1] && +        !is_separator(str[2])) { +      return str.find_first_of(separators, 2); +    } + +    // case "/" +    if (str.size() > 0 && is_separator(str[0])) +      return 0; + +    return StringRef::npos; +  } + +  size_t parent_path_end(StringRef path) { +    size_t end_pos = filename_pos(path); + +    bool filename_was_sep = path.size() > 0 && is_separator(path[end_pos]); + +    // Skip separators except for root dir. +    size_t root_dir_pos = root_dir_start(path.substr(0, end_pos)); + +    while(end_pos > 0 && +          (end_pos - 1) != root_dir_pos && +          is_separator(path[end_pos - 1])) +      --end_pos; + +    if (end_pos == 1 && root_dir_pos == 0 && filename_was_sep) +      return StringRef::npos; + +    return end_pos; +  } +} // end unnamed namespace + +enum FSEntity { +  FS_Dir, +  FS_File, +  FS_Name +}; + +// Implemented in Unix/Path.inc and Windows/Path.inc. +static std::error_code TempDir(SmallVectorImpl<char> &result); + +static std::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. +    if (!sys::path::is_absolute(Twine(ModelStorage))) { +      SmallString<128> TDir; +      if (std::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: { +    if (std::error_code EC = +            sys::fs::openFileForWrite(Twine(ResultPath.begin()), ResultFD, +                                      sys::fs::F_RW | sys::fs::F_Excl, Mode)) { +      if (EC == errc::file_exists) +        goto retry_random_path; +      return EC; +    } + +    return std::error_code(); +  } + +  case FS_Name: { +    bool Exists; +    std::error_code EC = sys::fs::exists(ResultPath.begin(), Exists); +    if (EC) +      return EC; +    if (Exists) +      goto retry_random_path; +    return std::error_code(); +  } + +  case FS_Dir: { +    if (std::error_code EC = +            sys::fs::create_directory(ResultPath.begin(), false)) { +      if (EC == errc::file_exists) +        goto retry_random_path; +      return EC; +    } +    return std::error_code(); +  } +  } +  llvm_unreachable("Invalid Type"); +} + +namespace llvm { +namespace sys  { +namespace path { + +const_iterator begin(StringRef path) { +  const_iterator i; +  i.Path      = path; +  i.Component = find_first_component(path); +  i.Position  = 0; +  return i; +} + +const_iterator end(StringRef path) { +  const_iterator i; +  i.Path      = path; +  i.Position  = path.size(); +  return i; +} + +const_iterator &const_iterator::operator++() { +  assert(Position < Path.size() && "Tried to increment past end!"); + +  // Increment Position to past the current component +  Position += Component.size(); + +  // Check for end. +  if (Position == Path.size()) { +    Component = StringRef(); +    return *this; +  } + +  // Both POSIX and Windows treat paths that begin with exactly two separators +  // specially. +  bool was_net = Component.size() > 2 && +    is_separator(Component[0]) && +    Component[1] == Component[0] && +    !is_separator(Component[2]); + +  // Handle separators. +  if (is_separator(Path[Position])) { +    // Root dir. +    if (was_net +#ifdef LLVM_ON_WIN32 +        // c:/ +        || Component.endswith(":") +#endif +        ) { +      Component = Path.substr(Position, 1); +      return *this; +    } + +    // Skip extra separators. +    while (Position != Path.size() && +           is_separator(Path[Position])) { +      ++Position; +    } + +    // Treat trailing '/' as a '.'. +    if (Position == Path.size()) { +      --Position; +      Component = "."; +      return *this; +    } +  } + +  // Find next component. +  size_t end_pos = Path.find_first_of(separators, Position); +  Component = Path.slice(Position, end_pos); + +  return *this; +} + +const_iterator &const_iterator::operator--() { +  // If we're at the end and the previous char was a '/', return '.' unless +  // we are the root path. +  size_t root_dir_pos = root_dir_start(Path); +  if (Position == Path.size() && +      Path.size() > root_dir_pos + 1 && +      is_separator(Path[Position - 1])) { +    --Position; +    Component = "."; +    return *this; +  } + +  // Skip separators unless it's the root directory. +  size_t end_pos = Position; + +  while(end_pos > 0 && +        (end_pos - 1) != root_dir_pos && +        is_separator(Path[end_pos - 1])) +    --end_pos; + +  // Find next separator. +  size_t start_pos = filename_pos(Path.substr(0, end_pos)); +  Component = Path.slice(start_pos, end_pos); +  Position = start_pos; +  return *this; +} + +bool const_iterator::operator==(const const_iterator &RHS) const { +  return Path.begin() == RHS.Path.begin() && +         Position == RHS.Position; +} + +bool const_iterator::operator!=(const const_iterator &RHS) const { +  return !(*this == RHS); +} + +ptrdiff_t const_iterator::operator-(const const_iterator &RHS) const { +  return Position - RHS.Position; +} + +const StringRef root_path(StringRef path) { +  const_iterator b = begin(path), +                 pos = b, +                 e = end(path); +  if (b != e) { +    bool has_net = b->size() > 2 && is_separator((*b)[0]) && (*b)[1] == (*b)[0]; +    bool has_drive = +#ifdef LLVM_ON_WIN32 +      b->endswith(":"); +#else +      false; +#endif + +    if (has_net || has_drive) { +      if ((++pos != e) && is_separator((*pos)[0])) { +        // {C:/,//net/}, so get the first two components. +        return path.substr(0, b->size() + pos->size()); +      } else { +        // just {C:,//net}, return the first component. +        return *b; +      } +    } + +    // POSIX style root directory. +    if (is_separator((*b)[0])) { +      return *b; +    } +  } + +  return StringRef(); +} + +const StringRef root_name(StringRef path) { +  const_iterator b = begin(path), +                 e = end(path); +  if (b != e) { +    bool has_net = b->size() > 2 && is_separator((*b)[0]) && (*b)[1] == (*b)[0]; +    bool has_drive = +#ifdef LLVM_ON_WIN32 +      b->endswith(":"); +#else +      false; +#endif + +    if (has_net || has_drive) { +      // just {C:,//net}, return the first component. +      return *b; +    } +  } + +  // No path or no name. +  return StringRef(); +} + +const StringRef root_directory(StringRef path) { +  const_iterator b = begin(path), +                 pos = b, +                 e = end(path); +  if (b != e) { +    bool has_net = b->size() > 2 && is_separator((*b)[0]) && (*b)[1] == (*b)[0]; +    bool has_drive = +#ifdef LLVM_ON_WIN32 +      b->endswith(":"); +#else +      false; +#endif + +    if ((has_net || has_drive) && +        // {C:,//net}, skip to the next component. +        (++pos != e) && is_separator((*pos)[0])) { +      return *pos; +    } + +    // POSIX style root directory. +    if (!has_net && is_separator((*b)[0])) { +      return *b; +    } +  } + +  // No path or no root. +  return StringRef(); +} + +const StringRef relative_path(StringRef path) { +  StringRef root = root_path(path); +  return path.substr(root.size()); +} + +void append(SmallVectorImpl<char> &path, const Twine &a, +                                         const Twine &b, +                                         const Twine &c, +                                         const Twine &d) { +  SmallString<32> a_storage; +  SmallString<32> b_storage; +  SmallString<32> c_storage; +  SmallString<32> d_storage; + +  SmallVector<StringRef, 4> components; +  if (!a.isTriviallyEmpty()) components.push_back(a.toStringRef(a_storage)); +  if (!b.isTriviallyEmpty()) components.push_back(b.toStringRef(b_storage)); +  if (!c.isTriviallyEmpty()) components.push_back(c.toStringRef(c_storage)); +  if (!d.isTriviallyEmpty()) components.push_back(d.toStringRef(d_storage)); + +  for (SmallVectorImpl<StringRef>::const_iterator i = components.begin(), +                                                  e = components.end(); +                                                  i != e; ++i) { +    bool path_has_sep = !path.empty() && is_separator(path[path.size() - 1]); +    bool component_has_sep = !i->empty() && is_separator((*i)[0]); +    bool is_root_name = has_root_name(*i); + +    if (path_has_sep) { +      // Strip separators from beginning of component. +      size_t loc = i->find_first_not_of(separators); +      StringRef c = i->substr(loc); + +      // Append it. +      path.append(c.begin(), c.end()); +      continue; +    } + +    if (!component_has_sep && !(path.empty() || is_root_name)) { +      // Add a separator. +      path.push_back(preferred_separator); +    } + +    path.append(i->begin(), i->end()); +  } +} + +void append(SmallVectorImpl<char> &path, +            const_iterator begin, const_iterator end) { +  for (; begin != end; ++begin) +    path::append(path, *begin); +} + +const StringRef parent_path(StringRef path) { +  size_t end_pos = parent_path_end(path); +  if (end_pos == StringRef::npos) +    return StringRef(); +  else +    return path.substr(0, end_pos); +} + +void remove_filename(SmallVectorImpl<char> &path) { +  size_t end_pos = parent_path_end(StringRef(path.begin(), path.size())); +  if (end_pos != StringRef::npos) +    path.set_size(end_pos); +} + +void replace_extension(SmallVectorImpl<char> &path, const Twine &extension) { +  StringRef p(path.begin(), path.size()); +  SmallString<32> ext_storage; +  StringRef ext = extension.toStringRef(ext_storage); + +  // Erase existing extension. +  size_t pos = p.find_last_of('.'); +  if (pos != StringRef::npos && pos >= filename_pos(p)) +    path.set_size(pos); + +  // Append '.' if needed. +  if (ext.size() > 0 && ext[0] != '.') +    path.push_back('.'); + +  // Append extension. +  path.append(ext.begin(), ext.end()); +} + +void native(const Twine &path, SmallVectorImpl<char> &result) { +  assert((!path.isSingleStringRef() || +          path.getSingleStringRef().data() != result.data()) && +         "path and result are not allowed to overlap!"); +  // Clear result. +  result.clear(); +  path.toVector(result); +  native(result); +} + +void native(SmallVectorImpl<char> &path) { +#ifdef LLVM_ON_WIN32 +  std::replace(path.begin(), path.end(), '/', '\\'); +#endif +} + +const StringRef filename(StringRef path) { +  return *(--end(path)); +} + +const StringRef stem(StringRef path) { +  StringRef fname = filename(path); +  size_t pos = fname.find_last_of('.'); +  if (pos == StringRef::npos) +    return fname; +  else +    if ((fname.size() == 1 && fname == ".") || +        (fname.size() == 2 && fname == "..")) +      return fname; +    else +      return fname.substr(0, pos); +} + +const StringRef extension(StringRef path) { +  StringRef fname = filename(path); +  size_t pos = fname.find_last_of('.'); +  if (pos == StringRef::npos) +    return StringRef(); +  else +    if ((fname.size() == 1 && fname == ".") || +        (fname.size() == 2 && fname == "..")) +      return StringRef(); +    else +      return fname.substr(pos); +} + +bool is_separator(char value) { +  switch(value) { +#ifdef LLVM_ON_WIN32 +    case '\\': // fall through +#endif +    case '/': return true; +    default: return false; +  } +} + +static const char preferred_separator_string[] = { preferred_separator, '\0' }; + +const StringRef get_separator() { +  return preferred_separator_string; +} + +void system_temp_directory(bool erasedOnReboot, SmallVectorImpl<char> &result) { +  result.clear(); + +#if defined(_CS_DARWIN_USER_TEMP_DIR) && defined(_CS_DARWIN_USER_CACHE_DIR) +  // On Darwin, use DARWIN_USER_TEMP_DIR or DARWIN_USER_CACHE_DIR. +  // macros defined in <unistd.h> on darwin >= 9 +  int ConfName = erasedOnReboot? _CS_DARWIN_USER_TEMP_DIR +                               : _CS_DARWIN_USER_CACHE_DIR; +  size_t ConfLen = confstr(ConfName, nullptr, 0); +  if (ConfLen > 0) { +    do { +      result.resize(ConfLen); +      ConfLen = confstr(ConfName, result.data(), result.size()); +    } while (ConfLen > 0 && ConfLen != result.size()); + +    if (ConfLen > 0) { +      assert(result.back() == 0); +      result.pop_back(); +      return; +    } + +    result.clear(); +  } +#endif + +  // Check whether the temporary directory is specified by an environment +  // variable. +  const char *EnvironmentVariable; +#ifdef LLVM_ON_WIN32 +  EnvironmentVariable = "TEMP"; +#else +  EnvironmentVariable = "TMPDIR"; +#endif +  if (char *RequestedDir = getenv(EnvironmentVariable)) { +    result.append(RequestedDir, RequestedDir + strlen(RequestedDir)); +    return; +  } + +  // Fall back to a system default. +  const char *DefaultResult; +#ifdef LLVM_ON_WIN32 +  (void)erasedOnReboot; +  DefaultResult = "C:\\TEMP"; +#else +  if (erasedOnReboot) +    DefaultResult = "/tmp"; +  else +    DefaultResult = "/var/tmp"; +#endif +  result.append(DefaultResult, DefaultResult + strlen(DefaultResult)); +} + +bool has_root_name(const Twine &path) { +  SmallString<128> path_storage; +  StringRef p = path.toStringRef(path_storage); + +  return !root_name(p).empty(); +} + +bool has_root_directory(const Twine &path) { +  SmallString<128> path_storage; +  StringRef p = path.toStringRef(path_storage); + +  return !root_directory(p).empty(); +} + +bool has_root_path(const Twine &path) { +  SmallString<128> path_storage; +  StringRef p = path.toStringRef(path_storage); + +  return !root_path(p).empty(); +} + +bool has_relative_path(const Twine &path) { +  SmallString<128> path_storage; +  StringRef p = path.toStringRef(path_storage); + +  return !relative_path(p).empty(); +} + +bool has_filename(const Twine &path) { +  SmallString<128> path_storage; +  StringRef p = path.toStringRef(path_storage); + +  return !filename(p).empty(); +} + +bool has_parent_path(const Twine &path) { +  SmallString<128> path_storage; +  StringRef p = path.toStringRef(path_storage); + +  return !parent_path(p).empty(); +} + +bool has_stem(const Twine &path) { +  SmallString<128> path_storage; +  StringRef p = path.toStringRef(path_storage); + +  return !stem(p).empty(); +} + +bool has_extension(const Twine &path) { +  SmallString<128> path_storage; +  StringRef p = path.toStringRef(path_storage); + +  return !extension(p).empty(); +} + +bool is_absolute(const Twine &path) { +  SmallString<128> path_storage; +  StringRef p = path.toStringRef(path_storage); + +  bool rootDir = has_root_directory(p), +#ifdef LLVM_ON_WIN32 +       rootName = has_root_name(p); +#else +       rootName = true; +#endif + +  return rootDir && rootName; +} + +bool is_relative(const Twine &path) { +  return !is_absolute(path); +} + +} // end namespace path + +namespace fs { + +std::error_code getUniqueID(const Twine Path, UniqueID &Result) { +  file_status Status; +  std::error_code EC = status(Path, Status); +  if (EC) +    return EC; +  Result = Status.getUniqueID(); +  return std::error_code(); +} + +std::error_code createUniqueFile(const Twine &Model, int &ResultFd, +                                 SmallVectorImpl<char> &ResultPath, +                                 unsigned Mode) { +  return createUniqueEntity(Model, ResultFd, ResultPath, false, Mode, FS_File); +} + +std::error_code createUniqueFile(const Twine &Model, +                                 SmallVectorImpl<char> &ResultPath) { +  int Dummy; +  return createUniqueEntity(Model, Dummy, ResultPath, false, 0, FS_Name); +} + +static std::error_code +createTemporaryFile(const Twine &Model, int &ResultFD, +                    llvm::SmallVectorImpl<char> &ResultPath, FSEntity Type) { +  SmallString<128> Storage; +  StringRef P = Model.toNullTerminatedStringRef(Storage); +  assert(P.find_first_of(separators) == StringRef::npos && +         "Model must be a simple filename."); +  // Use P.begin() so that createUniqueEntity doesn't need to recreate Storage. +  return createUniqueEntity(P.begin(), ResultFD, ResultPath, +                            true, owner_read | owner_write, Type); +} + +static std::error_code +createTemporaryFile(const Twine &Prefix, StringRef Suffix, int &ResultFD, +                    llvm::SmallVectorImpl<char> &ResultPath, FSEntity Type) { +  const char *Middle = Suffix.empty() ? "-%%%%%%" : "-%%%%%%."; +  return createTemporaryFile(Prefix + Middle + Suffix, ResultFD, ResultPath, +                             Type); +} + +std::error_code createTemporaryFile(const Twine &Prefix, StringRef Suffix, +                                    int &ResultFD, +                                    SmallVectorImpl<char> &ResultPath) { +  return createTemporaryFile(Prefix, Suffix, ResultFD, ResultPath, FS_File); +} + +std::error_code createTemporaryFile(const Twine &Prefix, StringRef Suffix, +                                    SmallVectorImpl<char> &ResultPath) { +  int Dummy; +  return createTemporaryFile(Prefix, Suffix, Dummy, ResultPath, FS_Name); +} + + +// This is a mkdtemp with a different pattern. We use createUniqueEntity mostly +// for consistency. We should try using mkdtemp. +std::error_code createUniqueDirectory(const Twine &Prefix, +                                      SmallVectorImpl<char> &ResultPath) { +  int Dummy; +  return createUniqueEntity(Prefix + "-%%%%%%", Dummy, ResultPath, +                            true, 0, FS_Dir); +} + +std::error_code make_absolute(SmallVectorImpl<char> &path) { +  StringRef p(path.data(), path.size()); + +  bool rootDirectory = path::has_root_directory(p), +#ifdef LLVM_ON_WIN32 +       rootName = path::has_root_name(p); +#else +       rootName = true; +#endif + +  // Already absolute. +  if (rootName && rootDirectory) +    return std::error_code(); + +  // All of the following conditions will need the current directory. +  SmallString<128> current_dir; +  if (std::error_code ec = current_path(current_dir)) +    return ec; + +  // Relative path. Prepend the current directory. +  if (!rootName && !rootDirectory) { +    // Append path to the current directory. +    path::append(current_dir, p); +    // Set path to the result. +    path.swap(current_dir); +    return std::error_code(); +  } + +  if (!rootName && rootDirectory) { +    StringRef cdrn = path::root_name(current_dir); +    SmallString<128> curDirRootName(cdrn.begin(), cdrn.end()); +    path::append(curDirRootName, p); +    // Set path to the result. +    path.swap(curDirRootName); +    return std::error_code(); +  } + +  if (rootName && !rootDirectory) { +    StringRef pRootName      = path::root_name(p); +    StringRef bRootDirectory = path::root_directory(current_dir); +    StringRef bRelativePath  = path::relative_path(current_dir); +    StringRef pRelativePath  = path::relative_path(p); + +    SmallString<128> res; +    path::append(res, pRootName, bRootDirectory, bRelativePath, pRelativePath); +    path.swap(res); +    return std::error_code(); +  } + +  llvm_unreachable("All rootName and rootDirectory combinations should have " +                   "occurred above!"); +} + +std::error_code create_directories(const Twine &Path, bool IgnoreExisting) { +  SmallString<128> PathStorage; +  StringRef P = Path.toStringRef(PathStorage); + +  // Be optimistic and try to create the directory +  std::error_code EC = create_directory(P, IgnoreExisting); +  // If we succeeded, or had any error other than the parent not existing, just +  // return it. +  if (EC != errc::no_such_file_or_directory) +    return EC; + +  // We failed because of a no_such_file_or_directory, try to create the +  // parent. +  StringRef Parent = path::parent_path(P); +  if (Parent.empty()) +    return EC; + +  if ((EC = create_directories(Parent))) +      return EC; + +  return create_directory(P, IgnoreExisting); +} + +std::error_code copy_file(const Twine &From, const Twine &To) { +  int ReadFD, WriteFD; +  if (std::error_code EC = openFileForRead(From, ReadFD)) +    return EC; +  if (std::error_code EC = openFileForWrite(To, WriteFD, F_None)) { +    close(ReadFD); +    return EC; +  } + +  const size_t BufSize = 4096; +  char *Buf = new char[BufSize]; +  int BytesRead = 0, BytesWritten = 0; +  for (;;) { +    BytesRead = read(ReadFD, Buf, BufSize); +    if (BytesRead <= 0) +      break; +    while (BytesRead) { +      BytesWritten = write(WriteFD, Buf, BytesRead); +      if (BytesWritten < 0) +        break; +      BytesRead -= BytesWritten; +    } +    if (BytesWritten < 0) +      break; +  } +  close(ReadFD); +  close(WriteFD); +  delete[] Buf; + +  if (BytesRead < 0 || BytesWritten < 0) +    return std::error_code(errno, std::generic_category()); +  return std::error_code(); +} + +bool exists(file_status status) { +  return status_known(status) && status.type() != file_type::file_not_found; +} + +bool status_known(file_status s) { +  return s.type() != file_type::status_error; +} + +bool is_directory(file_status status) { +  return status.type() == file_type::directory_file; +} + +std::error_code is_directory(const Twine &path, bool &result) { +  file_status st; +  if (std::error_code ec = status(path, st)) +    return ec; +  result = is_directory(st); +  return std::error_code(); +} + +bool is_regular_file(file_status status) { +  return status.type() == file_type::regular_file; +} + +std::error_code is_regular_file(const Twine &path, bool &result) { +  file_status st; +  if (std::error_code ec = status(path, st)) +    return ec; +  result = is_regular_file(st); +  return std::error_code(); +} + +bool is_other(file_status status) { +  return exists(status) && +         !is_regular_file(status) && +         !is_directory(status); +} + +void directory_entry::replace_filename(const Twine &filename, file_status st) { +  SmallString<128> path(Path.begin(), Path.end()); +  path::remove_filename(path); +  path::append(path, filename); +  Path = path.str(); +  Status = st; +} + +/// @brief Identify the magic in magic. +file_magic identify_magic(StringRef Magic) { +  if (Magic.size() < 4) +    return file_magic::unknown; +  switch ((unsigned char)Magic[0]) { +    case 0x00: { +      // COFF short import library file +      if (Magic[1] == (char)0x00 && Magic[2] == (char)0xff && +          Magic[3] == (char)0xff) +        return file_magic::coff_import_library; +      // Windows resource file +      const char Expected[] = { 0, 0, 0, 0, '\x20', 0, 0, 0, '\xff' }; +      if (Magic.size() >= sizeof(Expected) && +          memcmp(Magic.data(), Expected, sizeof(Expected)) == 0) +        return file_magic::windows_resource; +      // 0x0000 = COFF unknown machine type +      if (Magic[1] == 0) +        return file_magic::coff_object; +      break; +    } +    case 0xDE:  // 0x0B17C0DE = BC wraper +      if (Magic[1] == (char)0xC0 && Magic[2] == (char)0x17 && +          Magic[3] == (char)0x0B) +        return file_magic::bitcode; +      break; +    case 'B': +      if (Magic[1] == 'C' && Magic[2] == (char)0xC0 && Magic[3] == (char)0xDE) +        return file_magic::bitcode; +      break; +    case '!': +      if (Magic.size() >= 8) +        if (memcmp(Magic.data(),"!<arch>\n",8) == 0) +          return file_magic::archive; +      break; + +    case '\177': +      if (Magic.size() >= 18 && Magic[1] == 'E' && Magic[2] == 'L' && +          Magic[3] == 'F') { +        bool Data2MSB = Magic[5] == 2; +        unsigned high = Data2MSB ? 16 : 17; +        unsigned low  = Data2MSB ? 17 : 16; +        if (Magic[high] == 0) +          switch (Magic[low]) { +            default: break; +            case 1: return file_magic::elf_relocatable; +            case 2: return file_magic::elf_executable; +            case 3: return file_magic::elf_shared_object; +            case 4: return file_magic::elf_core; +          } +      } +      break; + +    case 0xCA: +      if (Magic[1] == char(0xFE) && Magic[2] == char(0xBA) && +          Magic[3] == char(0xBE)) { +        // This is complicated by an overlap with Java class files. +        // See the Mach-O section in /usr/share/file/magic for details. +        if (Magic.size() >= 8 && Magic[7] < 43) +          return file_magic::macho_universal_binary; +      } +      break; + +      // The two magic numbers for mach-o are: +      // 0xfeedface - 32-bit mach-o +      // 0xfeedfacf - 64-bit mach-o +    case 0xFE: +    case 0xCE: +    case 0xCF: { +      uint16_t type = 0; +      if (Magic[0] == char(0xFE) && Magic[1] == char(0xED) && +          Magic[2] == char(0xFA) && +          (Magic[3] == char(0xCE) || Magic[3] == char(0xCF))) { +        /* Native endian */ +        if (Magic.size() >= 16) type = Magic[14] << 8 | Magic[15]; +      } else if ((Magic[0] == char(0xCE) || Magic[0] == char(0xCF)) && +                 Magic[1] == char(0xFA) && Magic[2] == char(0xED) && +                 Magic[3] == char(0xFE)) { +        /* Reverse endian */ +        if (Magic.size() >= 14) type = Magic[13] << 8 | Magic[12]; +      } +      switch (type) { +        default: break; +        case 1: return file_magic::macho_object; +        case 2: return file_magic::macho_executable; +        case 3: return file_magic::macho_fixed_virtual_memory_shared_lib; +        case 4: return file_magic::macho_core; +        case 5: return file_magic::macho_preload_executable; +        case 6: return file_magic::macho_dynamically_linked_shared_lib; +        case 7: return file_magic::macho_dynamic_linker; +        case 8: return file_magic::macho_bundle; +        case 9: return file_magic::macho_dynamic_linker; +        case 10: return file_magic::macho_dsym_companion; +      } +      break; +    } +    case 0xF0: // PowerPC Windows +    case 0x83: // Alpha 32-bit +    case 0x84: // Alpha 64-bit +    case 0x66: // MPS R4000 Windows +    case 0x50: // mc68K +    case 0x4c: // 80386 Windows +    case 0xc4: // ARMNT Windows +      if (Magic[1] == 0x01) +        return file_magic::coff_object; + +    case 0x90: // PA-RISC Windows +    case 0x68: // mc68K Windows +      if (Magic[1] == 0x02) +        return file_magic::coff_object; +      break; + +    case 0x4d: // Possible MS-DOS stub on Windows PE file +      if (Magic[1] == 0x5a) { +        uint32_t off = +          *reinterpret_cast<const support::ulittle32_t*>(Magic.data() + 0x3c); +        // PE/COFF file, either EXE or DLL. +        if (off < Magic.size() && memcmp(Magic.data() + off, "PE\0\0",4) == 0) +          return file_magic::pecoff_executable; +      } +      break; + +    case 0x64: // x86-64 Windows. +      if (Magic[1] == char(0x86)) +        return file_magic::coff_object; +      break; + +    default: +      break; +  } +  return file_magic::unknown; +} + +std::error_code identify_magic(const Twine &Path, file_magic &Result) { +  int FD; +  if (std::error_code EC = openFileForRead(Path, FD)) +    return EC; + +  char Buffer[32]; +  int Length = read(FD, Buffer, sizeof(Buffer)); +  if (close(FD) != 0 || Length < 0) +    return std::error_code(errno, std::generic_category()); + +  Result = identify_magic(StringRef(Buffer, Length)); +  return std::error_code(); +} + +std::error_code directory_entry::status(file_status &result) const { +  return fs::status(Path, result); +} + +} // end namespace fs +} // end namespace sys +} // end namespace llvm + +// Include the truly platform-specific parts. +#if defined(LLVM_ON_UNIX) +#include "Unix/Path.inc" +#endif +#if defined(LLVM_ON_WIN32) +#include "Windows/Path.inc" +#endif | 
