[libc-commits] [libc] [libc] Implement lchown in unistd (PR #230851)

[Aman Maurya via libc-commits]

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@@ -0,0 +1,88 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// Unittests for lchown.
+///
+//===----------------------------------------------------------------------===//
+
+#include "hdr/fcntl_macros.h"
+#include "hdr/sys_stat_macros.h"
+#include "src/__support/CPP/scope.h"
+#include "src/fcntl/open.h"
+#include "src/unistd/close.h"
+#include "src/unistd/getgid.h"
+#include "src/unistd/getuid.h"
+#include "src/unistd/lchown.h"
+#include "src/unistd/symlink.h"
+#include "src/unistd/unlink.h"
+#include "test/UnitTest/ErrnoCheckingTest.h"
+#include "test/UnitTest/ErrnoSetterMatcher.h"
+#include "test/UnitTest/Test.h"
+
+using namespace LIBC_NAMESPACE::testing::ErrnoSetterMatcher;
+using LlvmLibcLchownTest = LIBC_NAMESPACE::testing::ErrnoCheckingTest;
+
+TEST_F(LlvmLibcLchownTest, LchownSuccessRegularFile) {
+  uid_t my_uid = LIBC_NAMESPACE::getuid();
+  gid_t my_gid = LIBC_NAMESPACE::getgid();
+  constexpr const char *FILENAME = "lchown_regular.test";
+  auto TEST_FILE = libc_make_test_file_path(FILENAME);
+
+  int write_fd = LIBC_NAMESPACE::open(TEST_FILE, O_WRONLY | O_CREAT, S_IRWXU);
+  ASSERT_ERRNO_SUCCESS();
+  ASSERT_GT(write_fd, 0);
+  ASSERT_THAT(LIBC_NAMESPACE::close(write_fd), Succeeds(0));
+
+  LIBC_NAMESPACE::cpp::scope_exit cleanup(
+      [&] { EXPECT_THAT(LIBC_NAMESPACE::unlink(TEST_FILE), Succeeds(0)); });
+
+  // Change ownership to current user/group on a regular file.
+  ASSERT_THAT(LIBC_NAMESPACE::lchown(TEST_FILE, my_uid, my_gid), Succeeds(0));
+
+  // Passing -1 for owner and group leaves them unchanged without error.
+  ASSERT_THAT(LIBC_NAMESPACE::lchown(TEST_FILE, static_cast<uid_t>(-1),
+                                     static_cast<gid_t>(-1)),
+              Succeeds(0));
+}
+
+TEST_F(LlvmLibcLchownTest, LchownSuccessSymlink) {
+  uid_t my_uid = LIBC_NAMESPACE::getuid();
+  gid_t my_gid = LIBC_NAMESPACE::getgid();
+  constexpr const char *TARGET_FILENAME = "lchown_target.test";
+  constexpr const char *LINK_FILENAME = "lchown_symlink.test";
+  auto TARGET_FILE = libc_make_test_file_path(TARGET_FILENAME);
+  auto LINK_FILE = libc_make_test_file_path(LINK_FILENAME);
+
+  int write_fd = LIBC_NAMESPACE::open(TARGET_FILE, O_WRONLY | O_CREAT, S_IRWXU);
+  ASSERT_ERRNO_SUCCESS();
+  ASSERT_GT(write_fd, 0);
+  ASSERT_THAT(LIBC_NAMESPACE::close(write_fd), Succeeds(0));
+
+  LIBC_NAMESPACE::cpp::scope_exit cleanup_target(
+      [&] { EXPECT_THAT(LIBC_NAMESPACE::unlink(TARGET_FILE), Succeeds(0)); });
+
+  // Create a symbolic link to the target file.
+  ASSERT_THAT(LIBC_NAMESPACE::symlink(TARGET_FILE, LINK_FILE), Succeeds(0));
+
+  LIBC_NAMESPACE::cpp::scope_exit cleanup_link(
+      [&] { EXPECT_THAT(LIBC_NAMESPACE::unlink(LINK_FILE), Succeeds(0)); });
+
+  // lchown should operate on the symbolic link itself.
----------------
amanmaurya92 wrote:

now I updated the test to create and test lchown on a dangling symlink.

https://github.com/llvm/llvm-project/pull/230851