#include <signal.h>
#include <fcntl.h>
#include <ctype.h>
-#include <termios.h>
#include <unistd.h>
/* This is in netdevice.h. However, this compile will fail miserably if
#if !defined(__GLIBC__) || __GLIBC__ >= 2
#include <asm/types.h> /* glibc 2 conflicts with linux/types.h */
-#include <asm/ioctls.h>
#include <net/if.h>
#include <net/if_arp.h>
#include <net/route.h>
#include <sys/locks.h>
#endif
-#ifndef BOTHER
-#define BOTHER 0010000
-#endif
-struct termios2 {
- unsigned int c_iflag;
- unsigned int c_oflag;
- unsigned int c_cflag;
- unsigned int c_lflag;
- unsigned char c_line;
- unsigned char c_cc[19];
- unsigned int c_ispeed;
- unsigned int c_ospeed;
-};
+/*
+ * Instead of system header file <termios.h> use local "termios_linux.h" header
+ * file as it provides additional support for arbitrary baud rates via BOTHER.
+ */
+#include "termios_linux.h"
#ifdef INET6
#ifndef _LINUX_IN6_H
cfsetospeed (&tios, speed);
cfsetispeed (&tios, speed);
speed = cfgetospeed(&tios);
+ baud_rate = baud_rate_of(speed);
+ } else {
+#ifdef BOTHER
+ tios.c_cflag &= ~CBAUD;
+ tios.c_cflag |= BOTHER;
+ tios.c_ospeed = inspeed;
+#ifdef IBSHIFT
+ /* B0 sets input baudrate to the output baudrate */
+ tios.c_cflag &= ~(CBAUD << IBSHIFT);
+ tios.c_cflag |= B0 << IBSHIFT;
+ tios.c_ispeed = inspeed;
+#endif
+ baud_rate = inspeed;
+#else
+ baud_rate = 0;
+#endif
}
- baud_rate = baud_rate_of(speed);
}
else {
speed = cfgetospeed(&tios);
baud_rate = baud_rate_of(speed);
- }
-
- while (tcsetattr(tty_fd, TCSAFLUSH, &tios) < 0 && !ok_error(errno))
- if (errno != EINTR)
- fatal("tcsetattr: %m (line %d)", __LINE__);
- restore_term = 1;
-
-/* Most Linux architectures and drivers support arbitrary baud rate values via BOTHER */
-#ifdef TCGETS2
- if (!baud_rate) {
- struct termios2 tios2;
- if (ioctl(tty_fd, TCGETS2, &tios2) == 0) {
- if (inspeed) {
- tios2.c_cflag &= ~CBAUD;
- tios2.c_cflag |= BOTHER;
- tios2.c_ispeed = inspeed;
- tios2.c_ospeed = inspeed;
-#ifdef TCSETS2
- if (ioctl(tty_fd, TCSETS2, &tios2) == 0)
- baud_rate = inspeed;
+#ifdef BOTHER
+ if (!baud_rate)
+ baud_rate = tios.c_ospeed;
#endif
- } else {
- if ((tios2.c_cflag & CBAUD) == BOTHER && tios2.c_ospeed)
- baud_rate = tios2.c_ospeed;
- }
- }
}
-#endif
/*
* We can't proceed if the serial port baud rate is unknown,
else
fatal("Baud rate for %s is 0; need explicit baud rate", devnam);
}
+
+ while (tcsetattr(tty_fd, TCSAFLUSH, &tios) < 0 && !ok_error(errno))
+ if (errno != EINTR)
+ fatal("tcsetattr: %m (line %d)", __LINE__);
+ restore_term = 1;
}
/********************************************************************
--- /dev/null
+/* SPDX-License-Identifier: GPL-2.0+ OR BSD-4-Clause OR BSD-3-Clause OR BSD-2-Clause */
+/*
+ * termios fuctions to support arbitrary baudrates (on Linux)
+ *
+ * Copyright (c) 2021 Pali Rohár <pali@kernel.org>
+ * Copyright (c) 2021 Marek Behún <kabel@kernel.org>
+ */
+
+#ifndef _TERMIOS_LINUX_H_
+#define _TERMIOS_LINUX_H_
+
+/*
+ * We need to use raw TCGETS2/TCSETS2 or TCGETS/TCSETS ioctls with the BOTHER
+ * flag in struct termios2/termios, defined in Linux headers <asm/ioctls.h>
+ * and <asm/termbits.h>. Since these headers conflict with glibc's header file
+ * <termios.h>, it is not possible to use libc's termios functions and we need
+ * to reimplement them via ioctl() calls.
+ *
+ * An arbitrary baudrate is supported when the macro BOTHER is defined. The
+ * baudrate value itself is then stored into the c_ospeed and c_ispeed members.
+ * If ioctls TCGETS2/TCSETS2 are defined and supported then these fields are
+ * present in struct termios2, otherwise these fields are present in struct
+ * termios.
+ *
+ * Note that the Bnnn constants from <termios.h> need not be compatible with
+ * Bnnn constants from <asm/termbits.h>.
+ */
+
+#include <errno.h>
+#include <sys/ioctl.h>
+#include <sys/types.h>
+#include <asm/ioctls.h>
+#include <asm/termbits.h>
+
+#if defined(BOTHER) && defined(TCGETS2)
+#define termios termios2
+#endif
+
+static inline int tcgetattr(int fd, struct termios *t)
+{
+#if defined(BOTHER) && defined(TCGETS2)
+ return ioctl(fd, TCGETS2, t);
+#else
+ return ioctl(fd, TCGETS, t);
+#endif
+}
+
+static inline int tcsetattr(int fd, int a, const struct termios *t)
+{
+ int cmd;
+
+ switch (a) {
+#if defined(BOTHER) && defined(TCGETS2)
+ case TCSANOW:
+ cmd = TCSETS2;
+ break;
+ case TCSADRAIN:
+ cmd = TCSETSW2;
+ break;
+ case TCSAFLUSH:
+ cmd = TCSETSF2;
+ break;
+#else
+ case TCSANOW:
+ cmd = TCSETS;
+ break;
+ case TCSADRAIN:
+ cmd = TCSETSW;
+ break;
+ case TCSAFLUSH:
+ cmd = TCSETSF;
+ break;
+#endif
+ default:
+ errno = EINVAL;
+ return -1;
+ }
+
+ return ioctl(fd, cmd, t);
+}
+
+static inline int tcdrain(int fd)
+{
+ return ioctl(fd, TCSBRK, 1);
+}
+
+static inline int tcflush(int fd, int q)
+{
+ return ioctl(fd, TCFLSH, q);
+}
+
+static inline int tcsendbreak(int fd, int d)
+{
+#ifdef TCSBRKP
+ return ioctl(fd, TCSBRKP, d);
+#else
+ return ioctl(fd, TCSBRK, 0);
+#endif
+}
+
+static inline int tcflow(int fd, int a)
+{
+ return ioctl(fd, TCXONC, a);
+}
+
+static inline pid_t tcgetsid(int fd)
+{
+ pid_t sid;
+
+ if (ioctl(fd, TIOCGSID, &sid) < 0)
+ return (pid_t)-1;
+
+ return sid;
+}
+
+static inline speed_t cfgetospeed(const struct termios *t)
+{
+ return t->c_cflag & CBAUD;
+}
+
+static inline int cfsetospeed(struct termios *t, speed_t s)
+{
+ if (s & ~CBAUD) {
+ errno = EINVAL;
+ return -1;
+ }
+
+ t->c_cflag &= ~CBAUD;
+ t->c_cflag |= s;
+
+ return 0;
+}
+
+#ifdef IBSHIFT
+static inline speed_t cfgetispeed(const struct termios *t)
+{
+ speed_t s = (t->c_cflag >> IBSHIFT) & CBAUD;
+
+ if (s == B0)
+ return cfgetospeed(t);
+ else
+ return s;
+}
+
+static inline int cfsetispeed(struct termios *t, speed_t s)
+{
+ if (s == 0)
+ s = B0;
+
+ if (s & ~CBAUD) {
+ errno = EINVAL;
+ return -1;
+ }
+
+ t->c_cflag &= ~(CBAUD << IBSHIFT);
+ t->c_cflag |= s << IBSHIFT;
+
+ return 0;
+}
+#else /* !IBSHIFT */
+static inline speed_t cfgetispeed(const struct termios *t)
+{
+ return cfgetospeed(t);
+}
+
+static inline int cfsetispeed(struct termios *t, speed_t s)
+{
+ return cfsetospeed(t, s);
+}
+#endif /* !IBSHIFT */
+
+static inline int cfsetspeed(struct termios *t, speed_t s)
+{
+ if (cfsetospeed(t, s))
+ return -1;
+#ifdef IBSHIFT
+ if (cfsetispeed(t, s))
+ return -1;
+#endif
+
+ return 0;
+}
+
+static void cfmakeraw(struct termios *t)
+{
+ t->c_iflag &= ~(IGNBRK | BRKINT | PARMRK | ISTRIP | INLCR | IGNCR |
+ ICRNL | IXON);
+ t->c_oflag &= ~OPOST;
+ t->c_lflag &= ~(ECHO | ECHONL | ICANON | ISIG | IEXTEN);
+ t->c_cflag &= ~(CSIZE | PARENB);
+ t->c_cflag |= CS8;
+}
+
+#endif /* _TERMIOS_LINUX_H_ */