[clang] [clang-tools-extra] [libc] [libc][c11] implement ctime (PR #107285)

[Michael Jones via cfe-commits]

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=?utf-8?b?0JfQuNGI0LDQvSDQnNC40YDQtw=?Message-ID:
In-Reply-To: <llvm.org/llvm/llvm-project/pull/107285 at github.com>


================
@@ -0,0 +1,57 @@
+//===-- Unittests for ctime_r ---------------------------------------------===//
+//
+// 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/errno/libc_errno.h"
+#include "src/time/ctime_r.h"
+#include "src/time/time_utils.h"
+#include "test/UnitTest/Test.h"
+#include "test/src/time/TmHelper.h"
+
+using LIBC_NAMESPACE::time_utils::TimeConstants;
+
+TEST(LlvmLibcCtimeR, Nullptr) {
+  char *result;
+  result = LIBC_NAMESPACE::ctime_r(nullptr, nullptr);
+  ASSERT_ERRNO_EQ(EINVAL);
+  ASSERT_STREQ(nullptr, result);
+
+  char buffer[TimeConstants::ASCTIME_BUFFER_SIZE];
+  result = LIBC_NAMESPACE::ctime_r(nullptr, buffer);
+  ASSERT_ERRNO_EQ(EINVAL);
+  ASSERT_STREQ(nullptr, result);
+
+  time_t t;
+  result = LIBC_NAMESPACE::ctime_r(&tm_data, nullptr);
+  ASSERT_ERRNO_EQ(EINVAL);
+  ASSERT_STREQ(nullptr, result);
+}
+
+TEST(LlvmLibcCtimeR, ValidUnixTimestamp0) {
+  char buffer[TimeConstants::ASCTIME_BUFFER_SIZE];
+  struct time_t t = 0;
+  char *result;
+  // 1970-01-01 00:00:00. Test with a valid buffer size.
+  result = LIBC_NAMESPACE::ctime_r(t, buffer);
----------------
michaelrj-google wrote:

here and below, you need to pass a pointer to `t` to `ctime_r`
```suggestion
  result = LIBC_NAMESPACE::ctime_r(&t, buffer);
```

https://github.com/llvm/llvm-project/pull/107285