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[/] [or1k/] [trunk/] [gdb-5.3/] [gdb/] [ser-unix.c] - Rev 1773
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/* Serial interface for local (hardwired) serial ports on Un*x like systems Copyright 1992, 1993, 1994, 1995, 1996, 1998, 1999, 2000, 2001 Free Software Foundation, Inc. This file is part of GDB. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program 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 General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ #include "defs.h" #include "serial.h" #include "ser-unix.h" #include <fcntl.h> #include <sys/types.h> #include "terminal.h" #include <sys/socket.h> #include <sys/time.h> #include "gdb_string.h" #include "event-loop.h" #ifdef HAVE_TERMIOS struct hardwire_ttystate { struct termios termios; }; #endif /* termios */ #ifdef HAVE_TERMIO /* It is believed that all systems which have added job control to SVR3 (e.g. sco) have also added termios. Even if not, trying to figure out all the variations (TIOCGPGRP vs. TCGETPGRP, etc.) would be pretty bewildering. So we don't attempt it. */ struct hardwire_ttystate { struct termio termio; }; #endif /* termio */ #ifdef HAVE_SGTTY struct hardwire_ttystate { struct sgttyb sgttyb; struct tchars tc; struct ltchars ltc; /* Line discipline flags. */ int lmode; }; #endif /* sgtty */ static int hardwire_open (struct serial *scb, const char *name); static void hardwire_raw (struct serial *scb); static int wait_for (struct serial *scb, int timeout); static int hardwire_readchar (struct serial *scb, int timeout); static int do_hardwire_readchar (struct serial *scb, int timeout); static int generic_readchar (struct serial *scb, int timeout, int (*do_readchar) (struct serial *scb, int timeout)); static int rate_to_code (int rate); static int hardwire_setbaudrate (struct serial *scb, int rate); static void hardwire_close (struct serial *scb); static int get_tty_state (struct serial *scb, struct hardwire_ttystate * state); static int set_tty_state (struct serial *scb, struct hardwire_ttystate * state); static serial_ttystate hardwire_get_tty_state (struct serial *scb); static int hardwire_set_tty_state (struct serial *scb, serial_ttystate state); static int hardwire_noflush_set_tty_state (struct serial *, serial_ttystate, serial_ttystate); static void hardwire_print_tty_state (struct serial *, serial_ttystate, struct ui_file *); static int hardwire_drain_output (struct serial *); static int hardwire_flush_output (struct serial *); static int hardwire_flush_input (struct serial *); static int hardwire_send_break (struct serial *); static int hardwire_setstopbits (struct serial *, int); static int do_unix_readchar (struct serial *scb, int timeout); static timer_handler_func push_event; static handler_func fd_event; static void reschedule (struct serial *scb); void _initialize_ser_hardwire (void); extern int (*ui_loop_hook) (int); /* Open up a real live device for serial I/O */ static int hardwire_open (struct serial *scb, const char *name) { scb->fd = open (name, O_RDWR); if (scb->fd < 0) return -1; return 0; } static int get_tty_state (struct serial *scb, struct hardwire_ttystate *state) { #ifdef HAVE_TERMIOS if (tcgetattr (scb->fd, &state->termios) < 0) return -1; return 0; #endif #ifdef HAVE_TERMIO if (ioctl (scb->fd, TCGETA, &state->termio) < 0) return -1; return 0; #endif #ifdef HAVE_SGTTY if (ioctl (scb->fd, TIOCGETP, &state->sgttyb) < 0) return -1; if (ioctl (scb->fd, TIOCGETC, &state->tc) < 0) return -1; if (ioctl (scb->fd, TIOCGLTC, &state->ltc) < 0) return -1; if (ioctl (scb->fd, TIOCLGET, &state->lmode) < 0) return -1; return 0; #endif } static int set_tty_state (struct serial *scb, struct hardwire_ttystate *state) { #ifdef HAVE_TERMIOS if (tcsetattr (scb->fd, TCSANOW, &state->termios) < 0) return -1; return 0; #endif #ifdef HAVE_TERMIO if (ioctl (scb->fd, TCSETA, &state->termio) < 0) return -1; return 0; #endif #ifdef HAVE_SGTTY if (ioctl (scb->fd, TIOCSETN, &state->sgttyb) < 0) return -1; if (ioctl (scb->fd, TIOCSETC, &state->tc) < 0) return -1; if (ioctl (scb->fd, TIOCSLTC, &state->ltc) < 0) return -1; if (ioctl (scb->fd, TIOCLSET, &state->lmode) < 0) return -1; return 0; #endif } static serial_ttystate hardwire_get_tty_state (struct serial *scb) { struct hardwire_ttystate *state; state = (struct hardwire_ttystate *) xmalloc (sizeof *state); if (get_tty_state (scb, state)) return NULL; return (serial_ttystate) state; } static int hardwire_set_tty_state (struct serial *scb, serial_ttystate ttystate) { struct hardwire_ttystate *state; state = (struct hardwire_ttystate *) ttystate; return set_tty_state (scb, state); } static int hardwire_noflush_set_tty_state (struct serial *scb, serial_ttystate new_ttystate, serial_ttystate old_ttystate) { struct hardwire_ttystate new_state; #ifdef HAVE_SGTTY struct hardwire_ttystate *state = (struct hardwire_ttystate *) old_ttystate; #endif new_state = *(struct hardwire_ttystate *) new_ttystate; /* Don't change in or out of raw mode; we don't want to flush input. termio and termios have no such restriction; for them flushing input is separate from setting the attributes. */ #ifdef HAVE_SGTTY if (state->sgttyb.sg_flags & RAW) new_state.sgttyb.sg_flags |= RAW; else new_state.sgttyb.sg_flags &= ~RAW; /* I'm not sure whether this is necessary; the manpage just mentions RAW not CBREAK. */ if (state->sgttyb.sg_flags & CBREAK) new_state.sgttyb.sg_flags |= CBREAK; else new_state.sgttyb.sg_flags &= ~CBREAK; #endif return set_tty_state (scb, &new_state); } static void hardwire_print_tty_state (struct serial *scb, serial_ttystate ttystate, struct ui_file *stream) { struct hardwire_ttystate *state = (struct hardwire_ttystate *) ttystate; int i; #ifdef HAVE_TERMIOS fprintf_filtered (stream, "c_iflag = 0x%x, c_oflag = 0x%x,\n", (int) state->termios.c_iflag, (int) state->termios.c_oflag); fprintf_filtered (stream, "c_cflag = 0x%x, c_lflag = 0x%x\n", (int) state->termios.c_cflag, (int) state->termios.c_lflag); #if 0 /* This not in POSIX, and is not really documented by those systems which have it (at least not Sun). */ fprintf_filtered (stream, "c_line = 0x%x.\n", state->termios.c_line); #endif fprintf_filtered (stream, "c_cc: "); for (i = 0; i < NCCS; i += 1) fprintf_filtered (stream, "0x%x ", state->termios.c_cc[i]); fprintf_filtered (stream, "\n"); #endif #ifdef HAVE_TERMIO fprintf_filtered (stream, "c_iflag = 0x%x, c_oflag = 0x%x,\n", state->termio.c_iflag, state->termio.c_oflag); fprintf_filtered (stream, "c_cflag = 0x%x, c_lflag = 0x%x, c_line = 0x%x.\n", state->termio.c_cflag, state->termio.c_lflag, state->termio.c_line); fprintf_filtered (stream, "c_cc: "); for (i = 0; i < NCC; i += 1) fprintf_filtered (stream, "0x%x ", state->termio.c_cc[i]); fprintf_filtered (stream, "\n"); #endif #ifdef HAVE_SGTTY fprintf_filtered (stream, "sgttyb.sg_flags = 0x%x.\n", state->sgttyb.sg_flags); fprintf_filtered (stream, "tchars: "); for (i = 0; i < (int) sizeof (struct tchars); i++) fprintf_filtered (stream, "0x%x ", ((unsigned char *) &state->tc)[i]); fprintf_filtered (stream, "\n"); fprintf_filtered (stream, "ltchars: "); for (i = 0; i < (int) sizeof (struct ltchars); i++) fprintf_filtered (stream, "0x%x ", ((unsigned char *) &state->ltc)[i]); fprintf_filtered (stream, "\n"); fprintf_filtered (stream, "lmode: 0x%x\n", state->lmode); #endif } /* Wait for the output to drain away, as opposed to flushing (discarding) it */ static int hardwire_drain_output (struct serial *scb) { #ifdef HAVE_TERMIOS return tcdrain (scb->fd); #endif #ifdef HAVE_TERMIO return ioctl (scb->fd, TCSBRK, 1); #endif #ifdef HAVE_SGTTY /* Get the current state and then restore it using TIOCSETP, which should cause the output to drain and pending input to be discarded. */ { struct hardwire_ttystate state; if (get_tty_state (scb, &state)) { return (-1); } else { return (ioctl (scb->fd, TIOCSETP, &state.sgttyb)); } } #endif } static int hardwire_flush_output (struct serial *scb) { #ifdef HAVE_TERMIOS return tcflush (scb->fd, TCOFLUSH); #endif #ifdef HAVE_TERMIO return ioctl (scb->fd, TCFLSH, 1); #endif #ifdef HAVE_SGTTY /* This flushes both input and output, but we can't do better. */ return ioctl (scb->fd, TIOCFLUSH, 0); #endif } static int hardwire_flush_input (struct serial *scb) { ser_unix_flush_input (scb); #ifdef HAVE_TERMIOS return tcflush (scb->fd, TCIFLUSH); #endif #ifdef HAVE_TERMIO return ioctl (scb->fd, TCFLSH, 0); #endif #ifdef HAVE_SGTTY /* This flushes both input and output, but we can't do better. */ return ioctl (scb->fd, TIOCFLUSH, 0); #endif } static int hardwire_send_break (struct serial *scb) { #ifdef HAVE_TERMIOS return tcsendbreak (scb->fd, 0); #endif #ifdef HAVE_TERMIO return ioctl (scb->fd, TCSBRK, 0); #endif #ifdef HAVE_SGTTY { int status; struct timeval timeout; status = ioctl (scb->fd, TIOCSBRK, 0); /* Can't use usleep; it doesn't exist in BSD 4.2. */ /* Note that if this select() is interrupted by a signal it will not wait the full length of time. I think that is OK. */ timeout.tv_sec = 0; timeout.tv_usec = 250000; select (0, 0, 0, 0, &timeout); status = ioctl (scb->fd, TIOCCBRK, 0); return status; } #endif } static void hardwire_raw (struct serial *scb) { struct hardwire_ttystate state; if (get_tty_state (scb, &state)) fprintf_unfiltered (gdb_stderr, "get_tty_state failed: %s\n", safe_strerror (errno)); #ifdef HAVE_TERMIOS state.termios.c_iflag = 0; state.termios.c_oflag = 0; state.termios.c_lflag = 0; state.termios.c_cflag &= ~(CSIZE | PARENB); state.termios.c_cflag |= CLOCAL | CS8; state.termios.c_cc[VMIN] = 0; state.termios.c_cc[VTIME] = 0; #endif #ifdef HAVE_TERMIO state.termio.c_iflag = 0; state.termio.c_oflag = 0; state.termio.c_lflag = 0; state.termio.c_cflag &= ~(CSIZE | PARENB); state.termio.c_cflag |= CLOCAL | CS8; state.termio.c_cc[VMIN] = 0; state.termio.c_cc[VTIME] = 0; #endif #ifdef HAVE_SGTTY state.sgttyb.sg_flags |= RAW | ANYP; state.sgttyb.sg_flags &= ~(CBREAK | ECHO); #endif scb->current_timeout = 0; if (set_tty_state (scb, &state)) fprintf_unfiltered (gdb_stderr, "set_tty_state failed: %s\n", safe_strerror (errno)); } /* Wait for input on scb, with timeout seconds. Returns 0 on success, otherwise SERIAL_TIMEOUT or SERIAL_ERROR. For termio{s}, we actually just setup VTIME if necessary, and let the timeout occur in the read() in hardwire_read(). */ /* FIXME: cagney/1999-09-16: Don't replace this with the equivalent ser_unix*() until the old TERMIOS/SGTTY/... timer code has been flushed. . */ /* NOTE: cagney/1999-09-30: Much of the code below is dead. The only possible values of the TIMEOUT parameter are ONE and ZERO. Consequently all the code that tries to handle the possability of an overflowed timer is unnecessary. */ static int wait_for (struct serial *scb, int timeout) { #ifdef HAVE_SGTTY while (1) { struct timeval tv; fd_set readfds; int numfds; /* NOTE: Some OS's can scramble the READFDS when the select() call fails (ex the kernel with Red Hat 5.2). Initialize all arguments before each call. */ tv.tv_sec = timeout; tv.tv_usec = 0; FD_ZERO (&readfds); FD_SET (scb->fd, &readfds); if (timeout >= 0) numfds = select (scb->fd + 1, &readfds, 0, 0, &tv); else numfds = select (scb->fd + 1, &readfds, 0, 0, 0); if (numfds <= 0) if (numfds == 0) return SERIAL_TIMEOUT; else if (errno == EINTR) continue; else return SERIAL_ERROR; /* Got an error from select or poll */ return 0; } #endif /* HAVE_SGTTY */ #if defined HAVE_TERMIO || defined HAVE_TERMIOS if (timeout == scb->current_timeout) return 0; scb->current_timeout = timeout; { struct hardwire_ttystate state; if (get_tty_state (scb, &state)) fprintf_unfiltered (gdb_stderr, "get_tty_state failed: %s\n", safe_strerror (errno)); #ifdef HAVE_TERMIOS if (timeout < 0) { /* No timeout. */ state.termios.c_cc[VTIME] = 0; state.termios.c_cc[VMIN] = 1; } else { state.termios.c_cc[VMIN] = 0; state.termios.c_cc[VTIME] = timeout * 10; if (state.termios.c_cc[VTIME] != timeout * 10) { /* If c_cc is an 8-bit signed character, we can't go bigger than this. If it is always unsigned, we could use 25. */ scb->current_timeout = 12; state.termios.c_cc[VTIME] = scb->current_timeout * 10; scb->timeout_remaining = timeout - scb->current_timeout; } } #endif #ifdef HAVE_TERMIO if (timeout < 0) { /* No timeout. */ state.termio.c_cc[VTIME] = 0; state.termio.c_cc[VMIN] = 1; } else { state.termio.c_cc[VMIN] = 0; state.termio.c_cc[VTIME] = timeout * 10; if (state.termio.c_cc[VTIME] != timeout * 10) { /* If c_cc is an 8-bit signed character, we can't go bigger than this. If it is always unsigned, we could use 25. */ scb->current_timeout = 12; state.termio.c_cc[VTIME] = scb->current_timeout * 10; scb->timeout_remaining = timeout - scb->current_timeout; } } #endif if (set_tty_state (scb, &state)) fprintf_unfiltered (gdb_stderr, "set_tty_state failed: %s\n", safe_strerror (errno)); return 0; } #endif /* HAVE_TERMIO || HAVE_TERMIOS */ } /* Read a character with user-specified timeout. TIMEOUT is number of seconds to wait, or -1 to wait forever. Use timeout of 0 to effect a poll. Returns char if successful. Returns SERIAL_TIMEOUT if timeout expired, EOF if line dropped dead, or SERIAL_ERROR for any other error (see errno in that case). */ /* FIXME: cagney/1999-09-16: Don't replace this with the equivalent ser_unix*() until the old TERMIOS/SGTTY/... timer code has been flushed. */ /* NOTE: cagney/1999-09-16: This function is not identical to ser_unix_readchar() as part of replacing it with ser_unix*() merging will be required - this code handles the case where read() times out due to no data while ser_unix_readchar() doesn't expect that. */ static int do_hardwire_readchar (struct serial *scb, int timeout) { int status, delta; int detach = 0; if (timeout > 0) timeout++; /* We have to be able to keep the GUI alive here, so we break the original timeout into steps of 1 second, running the "keep the GUI alive" hook each time through the loop. Also, timeout = 0 means to poll, so we just set the delta to 0, so we will only go through the loop once. */ delta = (timeout == 0 ? 0 : 1); while (1) { /* N.B. The UI may destroy our world (for instance by calling remote_stop,) in which case we want to get out of here as quickly as possible. It is not safe to touch scb, since someone else might have freed it. The ui_loop_hook signals that we should exit by returning 1. */ if (ui_loop_hook) detach = ui_loop_hook (0); if (detach) return SERIAL_TIMEOUT; scb->timeout_remaining = (timeout < 0 ? timeout : timeout - delta); status = wait_for (scb, delta); if (status < 0) return status; status = read (scb->fd, scb->buf, BUFSIZ); if (status <= 0) { if (status == 0) { /* Zero characters means timeout (it could also be EOF, but we don't (yet at least) distinguish). */ if (scb->timeout_remaining > 0) { timeout = scb->timeout_remaining; continue; } else if (scb->timeout_remaining < 0) continue; else return SERIAL_TIMEOUT; } else if (errno == EINTR) continue; else return SERIAL_ERROR; /* Got an error from read */ } scb->bufcnt = status; scb->bufcnt--; scb->bufp = scb->buf; return *scb->bufp++; } } static int hardwire_readchar (struct serial *scb, int timeout) { return generic_readchar (scb, timeout, do_hardwire_readchar); } #ifndef B19200 #define B19200 EXTA #endif #ifndef B38400 #define B38400 EXTB #endif /* Translate baud rates from integers to damn B_codes. Unix should have outgrown this crap years ago, but even POSIX wouldn't buck it. */ static struct { int rate; int code; } baudtab[] = { { 50, B50 } , { 75, B75 } , { 110, B110 } , { 134, B134 } , { 150, B150 } , { 200, B200 } , { 300, B300 } , { 600, B600 } , { 1200, B1200 } , { 1800, B1800 } , { 2400, B2400 } , { 4800, B4800 } , { 9600, B9600 } , { 19200, B19200 } , { 38400, B38400 } , #ifdef B57600 { 57600, B57600 } , #endif #ifdef B115200 { 115200, B115200 } , #endif #ifdef B230400 { 230400, B230400 } , #endif #ifdef B460800 { 460800, B460800 } , #endif { -1, -1 } , }; static int rate_to_code (int rate) { int i; for (i = 0; baudtab[i].rate != -1; i++) { /* test for perfect macth. */ if (rate == baudtab[i].rate) return baudtab[i].code; else { /* check if it is in between valid values. */ if (rate < baudtab[i].rate) { if (i) { warning ("Invalid baud rate %d. Closest values are %d and %d.", rate, baudtab[i - 1].rate, baudtab[i].rate); } else { warning ("Invalid baud rate %d. Minimum value is %d.", rate, baudtab[0].rate); } return -1; } } } /* The requested speed was too large. */ warning ("Invalid baud rate %d. Maximum value is %d.", rate, baudtab[i - 1].rate); return -1; } static int hardwire_setbaudrate (struct serial *scb, int rate) { struct hardwire_ttystate state; int baud_code = rate_to_code (rate); if (baud_code < 0) { /* The baud rate was not valid. A warning has already been issued. */ errno = EINVAL; return -1; } if (get_tty_state (scb, &state)) return -1; #ifdef HAVE_TERMIOS cfsetospeed (&state.termios, baud_code); cfsetispeed (&state.termios, baud_code); #endif #ifdef HAVE_TERMIO #ifndef CIBAUD #define CIBAUD CBAUD #endif state.termio.c_cflag &= ~(CBAUD | CIBAUD); state.termio.c_cflag |= baud_code; #endif #ifdef HAVE_SGTTY state.sgttyb.sg_ispeed = baud_code; state.sgttyb.sg_ospeed = baud_code; #endif return set_tty_state (scb, &state); } static int hardwire_setstopbits (struct serial *scb, int num) { struct hardwire_ttystate state; int newbit; if (get_tty_state (scb, &state)) return -1; switch (num) { case SERIAL_1_STOPBITS: newbit = 0; break; case SERIAL_1_AND_A_HALF_STOPBITS: case SERIAL_2_STOPBITS: newbit = 1; break; default: return 1; } #ifdef HAVE_TERMIOS if (!newbit) state.termios.c_cflag &= ~CSTOPB; else state.termios.c_cflag |= CSTOPB; /* two bits */ #endif #ifdef HAVE_TERMIO if (!newbit) state.termio.c_cflag &= ~CSTOPB; else state.termio.c_cflag |= CSTOPB; /* two bits */ #endif #ifdef HAVE_SGTTY return 0; /* sgtty doesn't support this */ #endif return set_tty_state (scb, &state); } static void hardwire_close (struct serial *scb) { if (scb->fd < 0) return; close (scb->fd); scb->fd = -1; } /* Generic operations used by all UNIX/FD based serial interfaces. */ serial_ttystate ser_unix_nop_get_tty_state (struct serial *scb) { /* allocate a dummy */ return (serial_ttystate) XMALLOC (int); } int ser_unix_nop_set_tty_state (struct serial *scb, serial_ttystate ttystate) { return 0; } void ser_unix_nop_raw (struct serial *scb) { return; /* Always in raw mode */ } /* Wait for input on scb, with timeout seconds. Returns 0 on success, otherwise SERIAL_TIMEOUT or SERIAL_ERROR. */ int ser_unix_wait_for (struct serial *scb, int timeout) { while (1) { int numfds; struct timeval tv; fd_set readfds, exceptfds; /* NOTE: Some OS's can scramble the READFDS when the select() call fails (ex the kernel with Red Hat 5.2). Initialize all arguments before each call. */ tv.tv_sec = timeout; tv.tv_usec = 0; FD_ZERO (&readfds); FD_ZERO (&exceptfds); FD_SET (scb->fd, &readfds); FD_SET (scb->fd, &exceptfds); if (timeout >= 0) numfds = select (scb->fd + 1, &readfds, 0, &exceptfds, &tv); else numfds = select (scb->fd + 1, &readfds, 0, &exceptfds, 0); if (numfds <= 0) { if (numfds == 0) return SERIAL_TIMEOUT; else if (errno == EINTR) continue; else return SERIAL_ERROR; /* Got an error from select or poll */ } return 0; } } /* Read a character with user-specified timeout. TIMEOUT is number of seconds to wait, or -1 to wait forever. Use timeout of 0 to effect a poll. Returns char if successful. Returns -2 if timeout expired, EOF if line dropped dead, or -3 for any other error (see errno in that case). */ static int do_unix_readchar (struct serial *scb, int timeout) { int status; int delta; /* We have to be able to keep the GUI alive here, so we break the original timeout into steps of 1 second, running the "keep the GUI alive" hook each time through the loop. Also, timeout = 0 means to poll, so we just set the delta to 0, so we will only go through the loop once. */ delta = (timeout == 0 ? 0 : 1); while (1) { /* N.B. The UI may destroy our world (for instance by calling remote_stop,) in which case we want to get out of here as quickly as possible. It is not safe to touch scb, since someone else might have freed it. The ui_loop_hook signals that we should exit by returning 1. */ if (ui_loop_hook) { if (ui_loop_hook (0)) return SERIAL_TIMEOUT; } status = ser_unix_wait_for (scb, delta); if (timeout > 0) timeout -= delta; /* If we got a character or an error back from wait_for, then we can break from the loop before the timeout is completed. */ if (status != SERIAL_TIMEOUT) { break; } /* If we have exhausted the original timeout, then generate a SERIAL_TIMEOUT, and pass it out of the loop. */ else if (timeout == 0) { status = SERIAL_TIMEOUT; break; } } if (status < 0) return status; while (1) { status = read (scb->fd, scb->buf, BUFSIZ); if (status != -1 || errno != EINTR) break; } if (status <= 0) { if (status == 0) return SERIAL_TIMEOUT; /* 0 chars means timeout [may need to distinguish between EOF & timeouts someday] */ else return SERIAL_ERROR; /* Got an error from read */ } scb->bufcnt = status; scb->bufcnt--; scb->bufp = scb->buf; return *scb->bufp++; } /* Perform operations common to both old and new readchar. */ /* Return the next character from the input FIFO. If the FIFO is empty, call the SERIAL specific routine to try and read in more characters. Initially data from the input FIFO is returned (fd_event() pre-reads the input into that FIFO. Once that has been emptied, further data is obtained by polling the input FD using the device specific readchar() function. Note: reschedule() is called after every read. This is because there is no guarentee that the lower level fd_event() poll_event() code (which also calls reschedule()) will be called. */ static int generic_readchar (struct serial *scb, int timeout, int (do_readchar) (struct serial *scb, int timeout)) { int ch; if (scb->bufcnt > 0) { ch = *scb->bufp; scb->bufcnt--; scb->bufp++; } else if (scb->bufcnt < 0) { /* Some errors/eof are are sticky. */ ch = scb->bufcnt; } else { ch = do_readchar (scb, timeout); if (ch < 0) { switch ((enum serial_rc) ch) { case SERIAL_EOF: case SERIAL_ERROR: /* Make the error/eof stick. */ scb->bufcnt = ch; break; case SERIAL_TIMEOUT: scb->bufcnt = 0; break; } } } reschedule (scb); return ch; } int ser_unix_readchar (struct serial *scb, int timeout) { return generic_readchar (scb, timeout, do_unix_readchar); } int ser_unix_nop_noflush_set_tty_state (struct serial *scb, serial_ttystate new_ttystate, serial_ttystate old_ttystate) { return 0; } void ser_unix_nop_print_tty_state (struct serial *scb, serial_ttystate ttystate, struct ui_file *stream) { /* Nothing to print. */ return; } int ser_unix_nop_setbaudrate (struct serial *scb, int rate) { return 0; /* Never fails! */ } int ser_unix_nop_setstopbits (struct serial *scb, int num) { return 0; /* Never fails! */ } int ser_unix_write (struct serial *scb, const char *str, int len) { int cc; while (len > 0) { cc = write (scb->fd, str, len); if (cc < 0) return 1; len -= cc; str += cc; } return 0; } int ser_unix_nop_flush_output (struct serial *scb) { return 0; } int ser_unix_flush_input (struct serial *scb) { if (scb->bufcnt >= 0) { scb->bufcnt = 0; scb->bufp = scb->buf; return 0; } else return SERIAL_ERROR; } int ser_unix_nop_send_break (struct serial *scb) { return 0; } int ser_unix_nop_drain_output (struct serial *scb) { return 0; } /* Event handling for ASYNC serial code. At any time the SERIAL device either: has an empty FIFO and is waiting on a FD event; or has a non-empty FIFO/error condition and is constantly scheduling timer events. ASYNC only stops pestering its client when it is de-async'ed or it is told to go away. */ /* Value of scb->async_state: */ enum { /* >= 0 (TIMER_SCHEDULED) */ /* The ID of the currently scheduled timer event. This state is rarely encountered. Timer events are one-off so as soon as the event is delivered the state is shanged to NOTHING_SCHEDULED. */ FD_SCHEDULED = -1, /* The fd_event() handler is scheduled. It is called when ever the file descriptor becomes ready. */ NOTHING_SCHEDULED = -2 /* Either no task is scheduled (just going into ASYNC mode) or a timer event has just gone off and the current state has been forced into nothing scheduled. */ }; /* Identify and schedule the next ASYNC task based on scb->async_state and scb->buf* (the input FIFO). A state machine is used to avoid the need to make redundant calls into the event-loop - the next scheduled task is only changed when needed. */ static void reschedule (struct serial *scb) { if (serial_is_async_p (scb)) { int next_state; switch (scb->async_state) { case FD_SCHEDULED: if (scb->bufcnt == 0) next_state = FD_SCHEDULED; else { delete_file_handler (scb->fd); next_state = create_timer (0, push_event, scb); } break; case NOTHING_SCHEDULED: if (scb->bufcnt == 0) { add_file_handler (scb->fd, fd_event, scb); next_state = FD_SCHEDULED; } else { next_state = create_timer (0, push_event, scb); } break; default: /* TIMER SCHEDULED */ if (scb->bufcnt == 0) { delete_timer (scb->async_state); add_file_handler (scb->fd, fd_event, scb); next_state = FD_SCHEDULED; } else next_state = scb->async_state; break; } if (serial_debug_p (scb)) { switch (next_state) { case FD_SCHEDULED: if (scb->async_state != FD_SCHEDULED) fprintf_unfiltered (gdb_stdlog, "[fd%d->fd-scheduled]\n", scb->fd); break; default: /* TIMER SCHEDULED */ if (scb->async_state == FD_SCHEDULED) fprintf_unfiltered (gdb_stdlog, "[fd%d->timer-scheduled]\n", scb->fd); break; } } scb->async_state = next_state; } } /* FD_EVENT: This is scheduled when the input FIFO is empty (and there is no pending error). As soon as data arrives, it is read into the input FIFO and the client notified. The client should then drain the FIFO using readchar(). If the FIFO isn't immediatly emptied, push_event() is used to nag the client until it is. */ static void fd_event (int error, void *context) { struct serial *scb = context; if (error != 0) { scb->bufcnt = SERIAL_ERROR; } else if (scb->bufcnt == 0) { /* Prime the input FIFO. The readchar() function is used to pull characters out of the buffer. See also generic_readchar(). */ int nr; do { nr = read (scb->fd, scb->buf, BUFSIZ); } while (nr == -1 && errno == EINTR); if (nr == 0) { scb->bufcnt = SERIAL_EOF; } else if (nr > 0) { scb->bufcnt = nr; scb->bufp = scb->buf; } else { scb->bufcnt = SERIAL_ERROR; } } scb->async_handler (scb, scb->async_context); reschedule (scb); } /* PUSH_EVENT: The input FIFO is non-empty (or there is a pending error). Nag the client until all the data has been read. In the case of errors, the client will need to close or de-async the device before naging stops. */ static void push_event (void *context) { struct serial *scb = context; scb->async_state = NOTHING_SCHEDULED; /* Timers are one-off */ scb->async_handler (scb, scb->async_context); /* re-schedule */ reschedule (scb); } /* Put the SERIAL device into/out-of ASYNC mode. */ void ser_unix_async (struct serial *scb, int async_p) { if (async_p) { /* Force a re-schedule. */ scb->async_state = NOTHING_SCHEDULED; if (serial_debug_p (scb)) fprintf_unfiltered (gdb_stdlog, "[fd%d->asynchronous]\n", scb->fd); reschedule (scb); } else { if (serial_debug_p (scb)) fprintf_unfiltered (gdb_stdlog, "[fd%d->synchronous]\n", scb->fd); /* De-schedule whatever tasks are currently scheduled. */ switch (scb->async_state) { case FD_SCHEDULED: delete_file_handler (scb->fd); break; NOTHING_SCHEDULED: break; default: /* TIMER SCHEDULED */ delete_timer (scb->async_state); break; } } } void _initialize_ser_hardwire (void) { struct serial_ops *ops = XMALLOC (struct serial_ops); memset (ops, sizeof (struct serial_ops), 0); ops->name = "hardwire"; ops->next = 0; ops->open = hardwire_open; ops->close = hardwire_close; /* FIXME: Don't replace this with the equivalent ser_unix*() until the old TERMIOS/SGTTY/... timer code has been flushed. cagney 1999-09-16. */ ops->readchar = hardwire_readchar; ops->write = ser_unix_write; ops->flush_output = hardwire_flush_output; ops->flush_input = hardwire_flush_input; ops->send_break = hardwire_send_break; ops->go_raw = hardwire_raw; ops->get_tty_state = hardwire_get_tty_state; ops->set_tty_state = hardwire_set_tty_state; ops->print_tty_state = hardwire_print_tty_state; ops->noflush_set_tty_state = hardwire_noflush_set_tty_state; ops->setbaudrate = hardwire_setbaudrate; ops->setstopbits = hardwire_setstopbits; ops->drain_output = hardwire_drain_output; ops->async = ser_unix_async; serial_add_interface (ops); }
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