[libc-commits] [libc] [libc] Add the get and set sys/xattr.h entrypoints. (PR #224729)

[Jeff Bailey via libc-commits]

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@@ -0,0 +1,192 @@
+//===----------------------------------------------------------------------===//
+//
+// 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
+/// Unit tests for setxattr.
+///
+//===----------------------------------------------------------------------===//
+
+#include "hdr/sys_stat_macros.h"
+#include "hdr/sys_xattr_macros.h"
+#include "hdr/types/ssize_t.h"
+#include "src/__support/CPP/scope.h"
+#include "src/__support/OSUtil/linux/syscall.h"
+#include "src/__support/libc_errno.h"
+#include "src/fcntl/creat.h"
+#include "src/sys/xattr/setxattr.h"
+#include "src/unistd/close.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"
+#include <sys/syscall.h>
+
+namespace {
+
+using namespace LIBC_NAMESPACE::testing::ErrnoSetterMatcher;
+using LlvmLibcSetxattrTest = LIBC_NAMESPACE::testing::ErrnoCheckingTest;
+using LIBC_NAMESPACE::cpp::scope_exit;
+using LIBC_NAMESPACE::cpp::string_view;
+
+int recreate_test_file(const char *path) {
+  LIBC_NAMESPACE::unlink(path);
+  LIBC_NAMESPACE::libc_errno = 0;
+  return LIBC_NAMESPACE::creat(path, S_IRWXU);
+}
+
+int recreate_test_symlink(const char *target, const char *linkpath) {
+  LIBC_NAMESPACE::unlink(linkpath);
+  LIBC_NAMESPACE::libc_errno = 0;
+  return LIBC_NAMESPACE::symlink(target, linkpath);
+}
+
+TEST_F(LlvmLibcSetxattrTest, SetAttributeDefaultFlags) {
+  const LIBC_NAMESPACE::CString TEST_FILE_NAME =
+      libc_make_test_file_path("testdata/setxattr_default_flags.txt");
+  constexpr const char *TEST_SYMLINK_TARGET = "setxattr_default_flags.txt";
+  const LIBC_NAMESPACE::CString TEST_SYMLINK_NAME =
+      libc_make_test_file_path("testdata/setxattr_default_flags_symlink.txt");
+
+  int fd = recreate_test_file(TEST_FILE_NAME);
+  ASSERT_ERRNO_SUCCESS();
+  ASSERT_THAT(LIBC_NAMESPACE::close(fd), Succeeds(0));
+
+  ASSERT_THAT(recreate_test_symlink(TEST_SYMLINK_TARGET, TEST_SYMLINK_NAME),
+              Succeeds(0));
+  scope_exit cleanup([&] {
+    ASSERT_THAT(LIBC_NAMESPACE::unlink(TEST_SYMLINK_NAME), Succeeds(0));
+    ASSERT_THAT(LIBC_NAMESPACE::unlink(TEST_FILE_NAME), Succeeds(0));
+  });
+
+  // Set an attribute through the test file name.
+  {
+    string_view XATTR_NAME = "user.test_attr_through_file";
+    string_view XATTR_VALUE = "test_value_through_file";
+    constexpr size_t BUFFER_SIZE = 32;
+    ASSERT_GE(BUFFER_SIZE, XATTR_VALUE.size());
+    char buffer[BUFFER_SIZE] = {};
+
+    ASSERT_THAT(LIBC_NAMESPACE::setxattr(TEST_FILE_NAME, XATTR_NAME.data(),
+                                         XATTR_VALUE.data(), XATTR_VALUE.size(),
+                                         /* flags = */ 0),
+                Succeeds(0));
+
+    ASSERT_EQ(static_cast<ssize_t>(XATTR_VALUE.size()),
+              LIBC_NAMESPACE::syscall_impl<ssize_t>(
+                  SYS_getxattr, static_cast<const char *>(TEST_FILE_NAME),
+                  XATTR_NAME.data(), buffer, BUFFER_SIZE));
+    EXPECT_EQ(string_view(buffer, XATTR_VALUE.size()), XATTR_VALUE);
+  }
+
+  // Set another attribute through the symlink to verify the correct syscall is
+  // used internally; setxattr instead of lsetxattr.
+  {
+    string_view XATTR_NAME = "user.test_attr_through_symlink";
+    string_view XATTR_VALUE = "test_value_through_symlink";
+    constexpr size_t BUFFER_SIZE = 32;
+    ASSERT_GE(BUFFER_SIZE, XATTR_VALUE.size());
+    char buffer[BUFFER_SIZE] = {};
+
+    ASSERT_THAT(LIBC_NAMESPACE::setxattr(TEST_SYMLINK_NAME, XATTR_NAME.data(),
+                                         XATTR_VALUE.data(), XATTR_VALUE.size(),
+                                         /* flags = */ 0),
+                Succeeds(0));
+
+    EXPECT_EQ(static_cast<ssize_t>(XATTR_VALUE.size()),
+              LIBC_NAMESPACE::syscall_impl<ssize_t>(
+                  SYS_getxattr, static_cast<const char *>(TEST_FILE_NAME),
+                  XATTR_NAME.data(), buffer, BUFFER_SIZE));
+    EXPECT_EQ(string_view(buffer, XATTR_VALUE.size()), XATTR_VALUE);
+  }
+}
+
+TEST_F(LlvmLibcSetxattrTest, SetAttributeWithNonzeroFlags) {
+  const LIBC_NAMESPACE::CString TEST_FILE_NAME =
+      libc_make_test_file_path("testdata/setxattr_nonzero_flags.txt");
+  int fd = recreate_test_file(TEST_FILE_NAME);
----------------
kaladron wrote:

This should be followed by a scoped_exit to unlink this after.

https://github.com/llvm/llvm-project/pull/224729