[llvm] r292907 - [Support] Add sys::fs::set_current_path() (aka chdir)

[Pavel Labath via llvm-commits]

Author: labath
Date: Tue Jan 24 04:32:03 2017
New Revision: 292907

URL: http://llvm.org/viewvc/llvm-project?rev=292907&view=rev
Log:
[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

Modified:
    llvm/trunk/include/llvm/Support/FileSystem.h
    llvm/trunk/lib/Support/Unix/Path.inc
    llvm/trunk/lib/Support/Windows/Path.inc
    llvm/trunk/unittests/Support/Path.cpp

Modified: llvm/trunk/include/llvm/Support/FileSystem.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Support/FileSystem.h?rev=292907&r1=292906&r2=292907&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Support/FileSystem.h (original)
+++ llvm/trunk/include/llvm/Support/FileSystem.h Tue Jan 24 04:32:03 2017
@@ -357,6 +357,13 @@ std::error_code create_hard_link(const T
 ///          otherwise a platform-specific error_code.
 std::error_code current_path(SmallVectorImpl<char> &result);
 
+/// @brief Set the current path.
+///
+/// @param path The path to set.
+/// @returns errc::success if the current path was successfully set,
+///          otherwise a platform-specific error_code.
+std::error_code set_current_path(const Twine &path);
+
 /// @brief Remove path. Equivalent to POSIX remove().
 ///
 /// @param path Input path.

Modified: llvm/trunk/lib/Support/Unix/Path.inc
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Support/Unix/Path.inc?rev=292907&r1=292906&r2=292907&view=diff
==============================================================================
--- llvm/trunk/lib/Support/Unix/Path.inc (original)
+++ llvm/trunk/lib/Support/Unix/Path.inc Tue Jan 24 04:32:03 2017
@@ -257,6 +257,16 @@ std::error_code current_path(SmallVector
   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;

Modified: llvm/trunk/lib/Support/Windows/Path.inc
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Support/Windows/Path.inc?rev=292907&r1=292906&r2=292907&view=diff
==============================================================================
--- llvm/trunk/lib/Support/Windows/Path.inc (original)
+++ llvm/trunk/lib/Support/Windows/Path.inc Tue Jan 24 04:32:03 2017
@@ -200,6 +200,18 @@ std::error_code current_path(SmallVector
   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;

Modified: llvm/trunk/unittests/Support/Path.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/unittests/Support/Path.cpp?rev=292907&r1=292906&r2=292907&view=diff
==============================================================================
--- llvm/trunk/unittests/Support/Path.cpp (original)
+++ llvm/trunk/unittests/Support/Path.cpp Tue Jan 24 04:32:03 2017
@@ -1135,4 +1135,23 @@ TEST_F(FileSystemTest, OpenFileForRead)
 
   ::close(FileDescriptor);
 }
+
+TEST_F(FileSystemTest, set_current_path) {
+  SmallString<128> path;
+
+  ASSERT_NO_ERROR(fs::current_path(path));
+  ASSERT_NE(TestDirectory, path);
+
+  struct RestorePath {
+    SmallString<128> path;
+    RestorePath(const SmallString<128> &path) : path(path) {}
+    ~RestorePath() { fs::set_current_path(path); }
+  } restore_path(path);
+
+  ASSERT_NO_ERROR(fs::set_current_path(TestDirectory));
+
+  ASSERT_NO_ERROR(fs::current_path(path));
+  ASSERT_EQ(TestDirectory, path);
+}
+
 } // anonymous namespace