libc/src/termios/linux/cfsetospeed.cpp

   1 //===-- Linux implementation of cfsetospeed -------------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 #include "src/termios/cfsetospeed.h"
  10 #include "src/errno/libc_errno.h"
  11
  12 #include "src/__support/common.h"
  13
  14 #include <termios.h>
  15
  16 namespace LIBC_NAMESPACE {
  17
  18 LLVM_LIBC_FUNCTION(int, cfsetospeed, (struct termios * t, speed_t speed)) {
  19   constexpr speed_t NOT_SPEED_MASK = ~speed_t(CBAUD);
  20   // A speed value is valid only if it is equal to one of the B<NN+> values.
  21   if (t == nullptr || ((speed & NOT_SPEED_MASK) != 0)) {
  22     libc_errno = EINVAL;
  23     return -1;
  24   }
  25
  26   t->c_cflag = (t->c_cflag & NOT_SPEED_MASK) | speed;
  27   t->c_ospeed = speed;
  28   return 0;
  29 }
  30
  31 } // namespace LIBC_NAMESPACE