[libc-commits] [libc] [libc] Add `shm_open/shm_unlink` (PR #84974)

[Schrodinger ZHU Yifan via libc-commits]

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@@ -0,0 +1,50 @@
+//===---------- Shared implementations for shm_open/shm_unlink ------------===//
+//
+// 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/CPP/array.h"
+#include "src/__support/CPP/optional.h"
+#include "src/__support/CPP/string_view.h"
+#include "src/errno/libc_errno.h"
+#include "src/string/memory_utils/inline_memcpy.h"
+
+// TODO: Get PATH_MAX via https://github.com/llvm/llvm-project/issues/85121
+#include <linux/limits.h>
+
+namespace LIBC_NAMESPACE {
+
+LIBC_INLINE_VAR constexpr cpp::string_view SHM_PREFIX = "/dev/shm/";
+using SHMPath = cpp::array<char, NAME_MAX + SHM_PREFIX.size() + 1>;
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SchrodingerZhu wrote:

It is a little bit annoying that I actually use the type in the function signature. I surround the shared code in a `shm_common` namespace instead.

https://github.com/llvm/llvm-project/pull/84974