[libc-commits] [libc] Reland: [libc] implement ioctl #85890 (PR #90317)

[Nick Desaulniers via libc-commits]

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@@ -0,0 +1,40 @@
+//===-- Unittests for ioctl -----------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#include "src/__support/OSUtil/syscall.h" // For internal syscall function.
+#include "src/errno/libc_errno.h"
+#include "src/fcntl/open.h"
+#include "src/sys/ioctl/ioctl.h"
+#include "src/unistd/close.h"
+#include "test/UnitTest/ErrnoSetterMatcher.h"
+#include "test/UnitTest/LibcTest.h"
+#include "test/UnitTest/Test.h"
+
+#include <linux/fs.h>
+
+TEST(LlvmLibcIoctlTest, InvalidFileDescriptor) {
+  using LIBC_NAMESPACE::testing::ErrnoSetterMatcher::Fails;
+  int fd = 10;
+  unsigned long request = 10;
+  int res = LIBC_NAMESPACE::ioctl(fd, request, NULL);
+  EXPECT_THAT(res, Fails(EBADF, -1));
+}
+
+TEST(LlvmLibcIoctlTest, ValidFileDescriptor) {
+  using LIBC_NAMESPACE::testing::ErrnoSetterMatcher::Succeeds;
+  LIBC_NAMESPACE::libc_errno = 0;
+  constexpr const char *FILENAME = "ioctl.test";
+  auto TEST_FILE = libc_make_test_file_path(FILENAME);
+  int fd = LIBC_NAMESPACE::open(TEST_FILE, O_WRONLY | O_CREAT, S_IRWXU);
----------------
nickdesaulniers wrote:

```
/android0/llvm-project/libc/test/src/sys/ioctl/linux/ioctl_test.cpp:33:64: error: use of undeclared identifier 'S_IRWXU'
   33 |   int fd = LIBC_NAMESPACE::open(TEST_FILE, O_WRONLY | O_CREAT, S_IRWXU);
      |                                                                ^
```
need to include `sys/stat.h`, though perhaps we should have a proxy header (akin to libc/hdr/sys_epoll_macros.h) for that.

https://github.com/llvm/llvm-project/pull/90317