[Support] Use std::filesystem::remove_all() in remove_directories()

See llvm#118677 for details.

Author: slydiman

llvm/lib/Support/Path.cpp

@@ -22,6 +22,7 @@
 #include "llvm/Support/Process.h"
 #include "llvm/Support/Signals.h"
 #include <cctype>
+#include <filesystem>
 
 #if !defined(_MSC_VER) && !defined(__MINGW32__)
 #include <unistd.h>
@@ -1206,6 +1207,13 @@ namespace llvm {
 namespace sys {
 namespace fs {
 
+std::error_code remove_directories(const Twine &path, bool IgnoreErrors) {
+  const std::filesystem::path Path(path.str());
+  std::error_code EC;
+  std::filesystem::remove_all(Path, EC);
+  return IgnoreErrors ? std::error_code() : EC;
+}
+
 TempFile::TempFile(StringRef Name, int FD)
     : TmpName(std::string(Name)), FD(FD) {}
 TempFile::TempFile(TempFile &&Other) { *this = std::move(Other); }

llvm/lib/Support/Unix/Path.inc

@@ -1272,46 +1272,6 @@ std::error_code closeFile(file_t &F) {
   return Process::SafelyCloseFileDescriptor(TmpF);
 }
 
-template <typename T>
-static std::error_code remove_directories_impl(const T &Entry,
-                                               bool IgnoreErrors) {
-  std::error_code EC;
-  directory_iterator Begin(Entry, EC, false);
-  directory_iterator End;
-  while (Begin != End) {
-    auto &Item = *Begin;
-    ErrorOr<basic_file_status> st = Item.status();
-    if (st) {
-      if (is_directory(*st)) {
-        EC = remove_directories_impl(Item, IgnoreErrors);
-        if (EC && !IgnoreErrors)
-          return EC;
-      }
-
-      EC = fs::remove(Item.path(), true);
-      if (EC && !IgnoreErrors)
-        return EC;
-    } else if (!IgnoreErrors) {
-      return st.getError();
-    }
-
-    Begin.increment(EC);
-    if (EC && !IgnoreErrors)
-      return EC;
-  }
-  return std::error_code();
-}
-
-std::error_code remove_directories(const Twine &path, bool IgnoreErrors) {
-  auto EC = remove_directories_impl(path, IgnoreErrors);
-  if (EC && !IgnoreErrors)
-    return EC;
-  EC = fs::remove(path, true);
-  if (EC && !IgnoreErrors)
-    return EC;
-  return std::error_code();
-}
-
 std::error_code real_path(const Twine &path, SmallVectorImpl<char> &dest,
                           bool expand_tilde) {
   dest.clear();

llvm/lib/Support/Windows/Path.inc

@@ -1372,32 +1372,6 @@ std::error_code closeFile(file_t &F) {
   return std::error_code();
 }
 
-std::error_code remove_directories(const Twine &path, bool IgnoreErrors) {
-  // Convert to utf-16.
-  SmallVector<wchar_t, 128> Path16;
-  std::error_code EC = widenPath(path, Path16);
-  if (EC && !IgnoreErrors)
-    return EC;
-
-  // SHFileOperation() accepts a list of paths, and so must be double null-
-  // terminated to indicate the end of the list.  The buffer is already null
-  // terminated, but since that null character is not considered part of the
-  // vector's size, pushing another one will just consume that byte.  So we
-  // need to push 2 null terminators.
-  Path16.push_back(0);
-  Path16.push_back(0);
-
-  SHFILEOPSTRUCTW shfos = {};
-  shfos.wFunc = FO_DELETE;
-  shfos.pFrom = Path16.data();
-  shfos.fFlags = FOF_NO_UI;
-
-  int result = ::SHFileOperationW(&shfos);
-  if (result != 0 && !IgnoreErrors)
-    return mapWindowsError(result);
-  return std::error_code();
-}
-
 static void expandTildeExpr(SmallVectorImpl<char> &Path) {
   // Path does not begin with a tilde expression.
   if (Path.empty() || Path[0] != '~')