[libc-commits] [libc] Sys call migrations of stdio and unistd (PR #196403)

[Jeff Bailey via libc-commits]

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@@ -0,0 +1,55 @@
+//===----------------------------------------------------------------------===//
+//
+// 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
+/// Syscall wrapper for dup2.
+///
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIBC_SRC___SUPPORT_OSUTIL_SYSCALL_WRAPPERS_DUP2_H
+#define LLVM_LIBC_SRC___SUPPORT_OSUTIL_SYSCALL_WRAPPERS_DUP2_H
+
+#include "hdr/fcntl_macros.h"
+#include "src/__support/OSUtil/linux/syscall.h" // syscall_impl
+#include "src/__support/common.h"
+#include "src/__support/error_or.h"
+#include "src/__support/macros/config.h"
+#include <sys/syscall.h> // For syscall numbers
+
+namespace LIBC_NAMESPACE_DECL {
+namespace linux_syscalls {
+
+LIBC_INLINE ErrorOr<int> dup2(int oldfd, int newfd) {
+#ifdef SYS_dup2
+  int ret = syscall_impl<int>(SYS_dup2, oldfd, newfd);
+#elif defined(SYS_dup3)
+  if (oldfd == newfd) {
+#if defined(SYS_fcntl)
+    int ret = syscall_impl<int>(SYS_fcntl, oldfd, F_GETFD);
+#elif defined(SYS_fcntl64)
+    int ret = syscall_impl<int>(SYS_fcntl64, oldfd, F_GETFD);
+#else
+#error "SYS_fcntl and SYS_fcntl64 syscalls not available."
+#endif
----------------
kaladron wrote:

fcntl isn't migrated yet.  I've made a note to do that later in this series.

https://github.com/llvm/llvm-project/pull/196403