[libc-commits] [libc] [libc][termios] Fix termios compatibility with glibc 2.42 or after. (PR #211039)

[via libc-commits]

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@@ -1,30 +1,36 @@
-//===-- Linux implementation of cfsetispeed -------------------------------===//
+//===----------------------------------------------------------------------===//
 //
 // 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
+/// Linux implementation of cfsetispeed.
+///
+//===----------------------------------------------------------------------===//
 
 #include "src/termios/cfsetispeed.h"
-
+#include "hdr/types/struct_termios.h"
 #include "src/__support/common.h"
 #include "src/__support/libc_errno.h"
-#include "src/__support/macros/config.h"
-
-#include <termios.h>
+#include "src/__support/macros/null_check.h"
+#include "src/termios/linux/speed_utils.h"
 
 namespace LIBC_NAMESPACE_DECL {
 
-LLVM_LIBC_FUNCTION(int, cfsetispeed, (struct termios * t, speed_t speed)) {
-  constexpr speed_t NOT_SPEED_MASK = ~speed_t(CBAUD);
+LLVM_LIBC_FUNCTION(int, cfsetispeed, (termios * t, speed_t speed)) {
+  LIBC_CRASH_ON_NULLPTR(t);
+  constexpr speed_t NOT_SPEED_MASK = ~static_cast<speed_t>(CBAUD);
+  speed_t encoded = encode_speed(speed);
   // A speed value is valid only if it is equal to one of the B<NN+> values.
-  if (t == nullptr || ((speed & NOT_SPEED_MASK) != 0)) {
+  if ((encoded & NOT_SPEED_MASK) != 0) {
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lntue wrote:

I'll keep `NOT_SPEED_MASK` to make it a bit clearer.

https://github.com/llvm/llvm-project/pull/211039