[Support] Add llvm::sys::fs::remove_directories.
We already have a function create_directories() which can create
an entire tree, and remove() which can remove an empty directory,
but we do not have remove_directories() which can remove an entire
tree. This patch adds such a function.
Because removing a directory tree can have dangerous consequences
when the tree contains a directory symlink, the patch here updates
the existing directory_iterator construct to optionally not follow
symlinks (previously it would always follow symlinks). The delete
algorithm uses this flag so that for symlinks, only the links are
removed, and not the targets.
On Windows this is implemented with SHFileOperation, which also
does not recurse into symbolic links or junctions.
Differential Revision: https://reviews.llvm.org/D30676
llvm-svn: 297314
diff --git a/llvm/lib/Support/Path.cpp b/llvm/lib/Support/Path.cpp
index 11fa3c3..fc3cf52 100644
--- a/llvm/lib/Support/Path.cpp
+++ b/llvm/lib/Support/Path.cpp
@@ -1189,7 +1189,7 @@
}
std::error_code directory_entry::status(file_status &result) const {
- return fs::status(Path, result);
+ return fs::status(Path, result, FollowSymlinks);
}
} // end namespace fs
diff --git a/llvm/lib/Support/Unix/Path.inc b/llvm/lib/Support/Unix/Path.inc
index 76e1ed2..568b1b4 100644
--- a/llvm/lib/Support/Unix/Path.inc
+++ b/llvm/lib/Support/Unix/Path.inc
@@ -618,7 +618,8 @@
}
std::error_code detail::directory_iterator_construct(detail::DirIterState &it,
- StringRef path){
+ StringRef path,
+ bool follow_symlinks) {
SmallString<128> path_null(path);
DIR *directory = ::opendir(path_null.c_str());
if (!directory)
@@ -627,7 +628,7 @@
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());
+ it.CurrentEntry = directory_entry(path_null.str(), follow_symlinks);
return directory_iterator_increment(it);
}
@@ -795,6 +796,46 @@
return std::error_code();
}
+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;
+ file_status st;
+ EC = Item.status(st);
+ if (EC && !IgnoreErrors)
+ return EC;
+
+ 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;
+
+ 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();
+}
+
} // end namespace fs
namespace path {
diff --git a/llvm/lib/Support/Windows/Path.inc b/llvm/lib/Support/Windows/Path.inc
index d2a2c0f..dc69222 100644
--- a/llvm/lib/Support/Windows/Path.inc
+++ b/llvm/lib/Support/Windows/Path.inc
@@ -26,6 +26,7 @@
// These two headers must be included last, and make sure shlobj is required
// after Windows.h to make sure it picks up our definition of _WIN32_WINNT
#include "WindowsSupport.h"
+#include <shellapi.h>
#include <shlobj.h>
#undef max
@@ -693,7 +694,8 @@
}
std::error_code detail::directory_iterator_construct(detail::DirIterState &it,
- StringRef path){
+ StringRef path,
+ bool follow_symlinks) {
SmallVector<wchar_t, 128> path_utf16;
if (std::error_code ec = widenPath(path, path_utf16))
@@ -738,7 +740,7 @@
it.IterationHandle = intptr_t(FindHandle.take());
SmallString<128> directory_entry_path(path);
path::append(directory_entry_path, directory_entry_name_utf8);
- it.CurrentEntry = directory_entry(directory_entry_path);
+ it.CurrentEntry = directory_entry(directory_entry_path, follow_symlinks);
return std::error_code();
}
@@ -920,6 +922,33 @@
return windows::UTF16ToUTF8(TempPath.data(), CharCount, ResultPath);
}
+
+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();
+}
+
} // end namespace fs
namespace path {