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-rw-r--r--libc/termios/tcsetattr.c120
1 files changed, 120 insertions, 0 deletions
diff --git a/libc/termios/tcsetattr.c b/libc/termios/tcsetattr.c
new file mode 100644
index 000000000..30ea46f4c
--- /dev/null
+++ b/libc/termios/tcsetattr.c
@@ -0,0 +1,120 @@
+/* Copyright (C) 1993, 1996, 1997, 1998 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Library General Public License as
+ published by the Free Software Foundation; either version 2 of the
+ License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Library General Public License for more details.
+
+ You should have received a copy of the GNU Library General Public
+ License along with the GNU C Library; see the file COPYING.LIB. If not,
+ write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ Boston, MA 02111-1307, USA. */
+
+#include <errno.h>
+#include <string.h>
+#include <termios.h>
+#include <sys/ioctl.h>
+#include <sys/types.h>
+
+/* The difference here is that the termios structure used in the
+ kernel is not the same as we use in the libc. Therefore we must
+ translate it here. */
+#include <kernel_termios.h>
+
+
+/* This is a gross hack around a kernel bug. If the cfsetispeed functions
+ is called with the SPEED argument set to zero this means use the same
+ speed as for output. But we don't have independent input and output
+ speeds and therefore cannot record this.
+
+ We use an unused bit in the `c_iflag' field to keep track of this
+ use of `cfsetispeed'. The value here must correspond to the one used
+ in `speed.c'. */
+#if !defined _HAVE_C_ISPEED || !defined _HAVE_C_OSPEED
+# define IBAUD0 020000000000
+#else
+/* If we have separate values for input and output speed don't bother
+ with this. Define the value as zero so the compiler sees we don't
+ have to do the AND below. */
+# define IBAUD0 0
+#endif
+
+
+/* Set the state of FD to *TERMIOS_P. */
+int
+tcsetattr (fd, optional_actions, termios_p)
+ int fd;
+ int optional_actions;
+ const struct termios *termios_p;
+{
+ struct __kernel_termios k_termios;
+ unsigned long int cmd;
+ int retval;
+
+ switch (optional_actions)
+ {
+ case TCSANOW:
+ cmd = TCSETS;
+ break;
+ case TCSADRAIN:
+ cmd = TCSETSW;
+ break;
+ case TCSAFLUSH:
+ cmd = TCSETSF;
+ break;
+ default:
+ errno=EINVAL;
+ return -1;
+ }
+
+ k_termios.c_iflag = termios_p->c_iflag & ~IBAUD0;
+ k_termios.c_oflag = termios_p->c_oflag;
+ k_termios.c_cflag = termios_p->c_cflag;
+ k_termios.c_lflag = termios_p->c_lflag;
+ k_termios.c_line = termios_p->c_line;
+#ifdef _HAVE_C_ISPEED
+ k_termios.c_ispeed = termios_p->c_ispeed;
+#endif
+#ifdef _HAVE_C_OSPEED
+ k_termios.c_ospeed = termios_p->c_ospeed;
+#endif
+ memcpy (&k_termios.c_cc[0], &termios_p->c_cc[0],
+ __KERNEL_NCCS * sizeof (cc_t));
+
+ retval = ioctl (fd, cmd, &k_termios);
+
+ if (retval == 0 && cmd == TCSETS)
+ {
+ /* The Linux kernel has a bug which silently ignore the invalid
+ c_cflag on pty. We have to check it here. */
+ int save = errno;
+ retval = ioctl (fd, TCGETS, &k_termios);
+ if (retval)
+ {
+ /* We cannot verify if the setting is ok. We don't return
+ an error (?). */
+ errno=save;
+ retval = 0;
+ }
+ else if ((termios_p->c_cflag & (PARENB | CREAD))
+ != (k_termios.c_cflag & (PARENB | CREAD))
+ || ((termios_p->c_cflag & CSIZE)
+ && ((termios_p->c_cflag & CSIZE)
+ != (k_termios.c_cflag & CSIZE))))
+ {
+ /* It looks like the Linux kernel silently changed the
+ PARENB/CREAD/CSIZE bits in c_cflag. Report it as an
+ error. */
+ errno=EINVAL;
+ retval = -1;
+ }
+ }
+
+ return retval;
+}