PR libstdc++/88881 fix filesystem::symlink_status for Windows

The fix for PR 88881 only added a workaround to filesystem::status, but
filesystem::symlink_status is also affected by the _wstat bug and needs
the same workaround.

The recent change to optimize path::parent_path() means that the
workaround can be simplified to just use parent_path().

	PR libstdc++/88881
	* src/c++17/fs_ops.cc [_GLIBCXX_FILESYSTEM_IS_WINDOWS]
	(status(const path&, error_code&)): Use parent_path() to remove
	trailing slash.
	(symlink_status(const path&, error_code&)): Duplicate workaround for
	bug in _wstat for paths with trailing slash.
	* testsuite/27_io/filesystem/operations/remove_all.cc: Check path
	with trailing slash.
	* testsuite/27_io/filesystem/operations/status.cc: Likewise.
	* testsuite/27_io/filesystem/operations/symlink_status.cc: Likewise.

From-SVN: r271755

libstdc++-v3/ChangeLog

@@ -1,5 +1,16 @@
 2019-05-29  Jonathan Wakely  <jwakely@redhat.com>
 
+	PR libstdc++/88881
+	* src/c++17/fs_ops.cc [_GLIBCXX_FILESYSTEM_IS_WINDOWS]
+	(status(const path&, error_code&)): Use parent_path() to remove
+	trailing slash.
+	(symlink_status(const path&, error_code&)): Duplicate workaround for
+	bug in _wstat for paths with trailing slash.
+	* testsuite/27_io/filesystem/operations/remove_all.cc: Check path
+	with trailing slash.
+	* testsuite/27_io/filesystem/operations/status.cc: Likewise.
+	* testsuite/27_io/filesystem/operations/symlink_status.cc: Likewise.
+
 	* src/c++17/fs_path.cc (path::parent_path()): Create whole path at
 	once instead of building it iteratively.
 

libstdc++-v3/src/c++17/fs_ops.cc

@@ -1395,23 +1395,19 @@ fs::status(const fs::path& p, error_code& ec) noexcept
 #if ! defined __MINGW64_VERSION_MAJOR || __MINGW64_VERSION_MAJOR < 6
   // stat() fails if there's a trailing slash (PR 88881)
   path p2;
-  if (p.has_relative_path())
+  if (p.has_relative_path() && !p.has_filename())
     {
-      wstring_view s = p.native();
-      const auto len = s.find_last_not_of(L"/\\") + wstring_view::size_type(1);
-      if (len != 0 && len != s.length())
+      __try
 	{
-	  __try
-	    {
-	      p2.assign(s.substr(0, len));
-	    }
-	  __catch(const bad_alloc&)
-	    {
-	      ec = std::make_error_code(std::errc::not_enough_memory);
-	      return status;
-	    }
+	  p2 = p.parent_path();
 	  str = p2.c_str();
 	}
+      __catch(const bad_alloc&)
+	{
+	  ec = std::make_error_code(std::errc::not_enough_memory);
+	  return status;
+	}
+      str = p2.c_str();
     }
 #endif
 #endif
@@ -1440,8 +1436,31 @@ fs::file_status
 fs::symlink_status(const fs::path& p, std::error_code& ec) noexcept
 {
   file_status status;
+  auto str = p.c_str();
+
+#if _GLIBCXX_FILESYSTEM_IS_WINDOWS
+#if ! defined __MINGW64_VERSION_MAJOR || __MINGW64_VERSION_MAJOR < 6
+  // stat() fails if there's a trailing slash (PR 88881)
+  path p2;
+  if (p.has_relative_path() && !p.has_filename())
+    {
+      __try
+	{
+	  p2 = p.parent_path();
+	  str = p2.c_str();
+	}
+      __catch(const bad_alloc&)
+	{
+	  ec = std::make_error_code(std::errc::not_enough_memory);
+	  return status;
+	}
+      str = p2.c_str();
+    }
+#endif
+#endif
+
   stat_type st;
-  if (posix::lstat(p.c_str(), &st))
+  if (posix::lstat(str, &st))
     {
       int err = errno;
       ec.assign(err, std::generic_category());

libstdc++-v3/testsuite/27_io/filesystem/operations/remove_all.cc

@@ -108,9 +108,42 @@ test02()
   VERIFY( !exists(dir) );
 }
 
+void
+test03()
+{
+  // PR libstdc++/88881 symlink_status confused by trailing slash on Windows
+  const std::error_code bad_ec = make_error_code(std::errc::invalid_argument);
+  unsigned removed;
+  std::error_code ec = bad_ec;
+  const auto p = __gnu_test::nonexistent_path() / ""; // with trailing slash
+
+  create_directories(p);
+  removed = remove_all(p, ec);
+  VERIFY( !ec );
+  VERIFY( removed == 1 );
+  VERIFY( !exists(p) );
+  create_directories(p);
+  removed = remove_all(p);
+  VERIFY( removed == 1 );
+  VERIFY( !exists(p) );
+
+  const auto p_subs = p/"foo/bar";
+  ec = bad_ec;
+  create_directories(p_subs);
+  removed = remove_all(p, ec);
+  VERIFY( !ec );
+  VERIFY( removed == 3 );
+  VERIFY( !exists(p) );
+  create_directories(p_subs);
+  remove_all(p);
+  VERIFY( removed == 3 );
+  VERIFY( !exists(p) );
+}
+
 int
 main()
 {
   test01();
   test02();
+  test03();
 }

libstdc++-v3/testsuite/27_io/filesystem/operations/status.cc

@@ -93,10 +93,20 @@ test03()
   fs::permissions(dir, fs::perms::owner_all, ec);
 }
 
+void
+test04()
+{
+  // PR libstdc++/88881
+  fs::path p = "./";
+  auto st = status(p);
+  VERIFY( is_directory(st) );
+}
+
 int
 main()
 {
   test01();
   test02();
   test03();
+  test04();
 }

libstdc++-v3/testsuite/27_io/filesystem/operations/symlink_status.cc

@@ -111,10 +111,20 @@ test03()
   fs::permissions(dir, fs::perms::owner_all, ec);
 }
 
+void
+test04()
+{
+  // PR libstdc++/88881
+  fs::path p = "./";
+  auto st = symlink_status(p);
+  VERIFY( is_directory(st) );
+}
+
 int
 main()
 {
   test01();
   test02();
   test03();
+  test04();
 }