1  /* Copyright (C) 1992-2023 Free Software Foundation, Inc.
       2     This file is part of the GNU C Library.
       3  
       4     The GNU C Library is free software; you can redistribute it and/or
       5     modify it under the terms of the GNU Lesser General Public
       6     License as published by the Free Software Foundation; either
       7     version 2.1 of the License, or (at your option) any later version.
       8  
       9     The GNU C Library is distributed in the hope that it will be useful,
      10     but WITHOUT ANY WARRANTY; without even the implied warranty of
      11     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
      12     Lesser General Public License for more details.
      13  
      14     You should have received a copy of the GNU Lesser General Public
      15     License along with the GNU C Library; if not, see
      16     <https://www.gnu.org/licenses/>.  */
      17  
      18  #include <errno.h>
      19  #include <string.h>
      20  #include <termios.h>
      21  #include <unistd.h>
      22  #include <sys/ioctl.h>
      23  #include <sys/types.h>
      24  #include <sysdep.h>
      25  
      26  /* The difference here is that the termios structure used in the
      27     kernel is not the same as we use in the libc.  Therefore we must
      28     translate it here.  */
      29  #include <kernel_termios.h>
      30  
      31  /* Put the state of FD into *TERMIOS_P.  */
      32  int
      33  __tcgetattr (int fd, struct termios *termios_p)
      34  {
      35    struct __kernel_termios k_termios;
      36    int retval;
      37  
      38    retval = INLINE_SYSCALL (ioctl, 3, fd, TCGETS, &k_termios);
      39  
      40    if (__glibc_likely (retval == 0))
      41      {
      42        termios_p->c_iflag = k_termios.c_iflag;
      43        termios_p->c_oflag = k_termios.c_oflag;
      44        termios_p->c_cflag = k_termios.c_cflag;
      45        termios_p->c_lflag = k_termios.c_lflag;
      46        termios_p->c_line = k_termios.c_line;
      47  #if _HAVE_STRUCT_TERMIOS_C_ISPEED
      48  # if _HAVE_C_ISPEED
      49        termios_p->c_ispeed = k_termios.c_ispeed;
      50  # else
      51        termios_p->c_ispeed = k_termios.c_cflag & (CBAUD | CBAUDEX);
      52  # endif
      53  #endif
      54  #if _HAVE_STRUCT_TERMIOS_C_OSPEED
      55  # if _HAVE_C_OSPEED
      56        termios_p->c_ospeed = k_termios.c_ospeed;
      57  # else
      58        termios_p->c_ospeed = k_termios.c_cflag & (CBAUD | CBAUDEX);
      59  # endif
      60  #endif
      61        if (sizeof (cc_t) == 1 || _POSIX_VDISABLE == 0
      62  	  || (unsigned char) _POSIX_VDISABLE == (unsigned char) -1)
      63  	memset (__mempcpy (&termios_p->c_cc[0], &k_termios.c_cc[0],
      64  			   __KERNEL_NCCS * sizeof (cc_t)),
      65  		_POSIX_VDISABLE, (NCCS - __KERNEL_NCCS) * sizeof (cc_t));
      66        else
      67  	{
      68  	  memcpy (&termios_p->c_cc[0], &k_termios.c_cc[0],
      69  		  __KERNEL_NCCS * sizeof (cc_t));
      70  
      71  	  for (size_t cnt = __KERNEL_NCCS; cnt < NCCS; ++cnt)
      72  	    termios_p->c_cc[cnt] = _POSIX_VDISABLE;
      73  	}
      74      }
      75  
      76    return retval;
      77  }
      78  
      79  libc_hidden_def (__tcgetattr)
      80  weak_alias (__tcgetattr, tcgetattr)