[libc-commits] [libc] [libc] Implement tcgetwinsize in termios (PR #228435)

[Michael Jones via libc-commits]

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@@ -0,0 +1,65 @@
+//===----------------------------------------------------------------------===//
+//
+// 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 tcgetwinsize.
+///
+//===----------------------------------------------------------------------===//
+
+#include "hdr/fcntl_macros.h"
+#include "hdr/types/struct_winsize.h"
+#include "src/__support/libc_errno.h"
+#include "src/fcntl/open.h"
+#include "src/termios/tcgetwinsize.h"
+#include "src/unistd/close.h"
+#include "src/unistd/pipe.h"
+#include "test/UnitTest/ErrnoCheckingTest.h"
+#include "test/UnitTest/ErrnoSetterMatcher.h"
+#include "test/UnitTest/Test.h"
+
+using LlvmLibcTcGetWinSizeTest = LIBC_NAMESPACE::testing::ErrnoCheckingTest;
+using namespace LIBC_NAMESPACE::testing::ErrnoSetterMatcher;
+
+TEST_F(LlvmLibcTcGetWinSizeTest, InvalidFileDescriptor) {
+  struct winsize ws;
+  ASSERT_THAT(LIBC_NAMESPACE::tcgetwinsize(-1, &ws), Fails(EBADF));
+}
+
+TEST_F(LlvmLibcTcGetWinSizeTest, NonTerminalFileDescriptor) {
+  int pipefd[2];
+  ASSERT_THAT(LIBC_NAMESPACE::pipe(pipefd), Succeeds(0));
+
+  struct winsize ws;
+  ASSERT_THAT(LIBC_NAMESPACE::tcgetwinsize(pipefd[0], &ws), Fails(ENOTTY));
+  ASSERT_THAT(LIBC_NAMESPACE::tcgetwinsize(pipefd[1], &ws), Fails(ENOTTY));
+
+  ASSERT_THAT(LIBC_NAMESPACE::close(pipefd[0]), Succeeds(0));
+  ASSERT_THAT(LIBC_NAMESPACE::close(pipefd[1]), Succeeds(0));
+}
+
+TEST_F(LlvmLibcTcGetWinSizeTest, TerminalSmokeTest) {
+  int fd = LIBC_NAMESPACE::open("/dev/tty", O_RDONLY);
+  if (fd < 0) {
+    // When /dev/tty is not available, gracefully skip the test.
+    libc_errno = 0;
+    return;
+  }
+  ASSERT_ERRNO_SUCCESS();
+
+  constexpr unsigned short SENTINEL_VAL = 0xFFFF;
+  struct winsize ws = {SENTINEL_VAL, SENTINEL_VAL, SENTINEL_VAL, SENTINEL_VAL};
+  int ret = LIBC_NAMESPACE::tcgetwinsize(fd, &ws);
+  if (ret < 0) {
+    ASSERT_ERRNO_EQ(ENOTTY);
+  } else {
+    ASSERT_ERRNO_SUCCESS();
+    EXPECT_NE(ws.ws_row, SENTINEL_VAL);
+    EXPECT_NE(ws.ws_col, SENTINEL_VAL);
+  }
+  ASSERT_THAT(LIBC_NAMESPACE::close(fd), Succeeds(0));
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michaelrj-google wrote:

closing the file and cleaning up should go in a `scope_exit` from `src/__support/CPP/scope.h`

https://github.com/llvm/llvm-project/pull/228435