[Support] Add sys::fs::set_current_path() (aka chdir)

Summary:
This adds a cross-platform way of setting the current working directory
analogous to the existing current_path() function used for retrieving
it. The function will be used in lldb.

Reviewers: rafael, silvas, zturner

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D29035

llvm-svn: 292907

2 files changed, 22 insertions, 0 deletions

diff --git a/llvm/lib/Support/Unix/Path.inc b/llvm/lib/Support/Unix/Path.inc
index 0bf9dbae220..f7334245a00 100644
--- a/llvm/lib/Support/Unix/Path.inc
+++ b/llvm/lib/Support/Unix/Path.inc
@@ -257,6 +257,16 @@ std::error_code current_path(SmallVectorImpl<char> &result) {
   return std::error_code();
 }
 
+std::error_code set_current_path(const Twine &path) {
+  SmallString<128> path_storage;
+  StringRef p = path.toNullTerminatedStringRef(path_storage);
+
+  if (::chdir(p.begin()) == -1)
+    return std::error_code(errno, std::generic_category());
+
+  return std::error_code();
+}
+
 std::error_code create_directory(const Twine &path, bool IgnoreExisting,
                                  perms Perms) {
   SmallString<128> path_storage;
diff --git a/llvm/lib/Support/Windows/Path.inc b/llvm/lib/Support/Windows/Path.inc
index 27b250b428a..3597b551098 100644
--- a/llvm/lib/Support/Windows/Path.inc
+++ b/llvm/lib/Support/Windows/Path.inc
@@ -200,6 +200,18 @@ std::error_code current_path(SmallVectorImpl<char> &result) {
   return UTF16ToUTF8(cur_path.begin(), cur_path.size(), result);
 }
 
+std::error_code set_current_path(const Twine &path) {
+  // Convert to utf-16.
+  SmallVector<wchar_t, 128> wide_path;
+  if (std::error_code ec = widenPath(path, wide_path))
+    return ec;
+
+  if (!::SetCurrentDirectoryW(wide_path.begin()))
+    return mapWindowsError(::GetLastError());
+
+  return std::error_code();
+}
+
 std::error_code create_directory(const Twine &path, bool IgnoreExisting,
                                  perms Perms) {
   SmallVector<wchar_t, 128> path_utf16;