/* term - terminal simulator Author: Andy Tanenbaum */ /* This program allows the user to turn a MINIX system into a dumb * terminal to communicate with a remote computer through one of the ttys. * It forks into two processes. The parent sits in a tight loop copying * from stdin to the tty. The child sits in a tight loop copying from * the tty to stdout. * * 2 Sept 88 BDE (Bruce D. Evans): Massive changes to make current settings the * default, allow any file as the "tty", support fancy baud rates and remove * references to and dependencies on modems and keyboards, so (e.g.) * a local login on /dev/tty1 can do an external login on /dev/tty2. * * 3 Sept 88 BDE: Split parent again to main process copies from stdin to a * pipe which is copied to the tty. This stops a blocked write to the * tty from hanging the program. * * 11 Oct 88 BDE: Cleaned up baud rates and parity stripping. * * Example usage: * term : baud, bits/char, parity from /dev/tty1 * term 9600 7 even : 9600 baud, 7 bits/char, even parity * term odd 300 7 : 300 baud, 7 bits/char, odd parity * term /dev/tty2 : use /dev/tty2 rather than /dev/tty1 * : Any argument starting with "/" is * : taken as the communication device. */ #include <sys/types.h> #include <minix/config.h> #include <fcntl.h> #include <sgtty.h> #include <signal.h> #define MAXARGS 3 /* maximum number of uart params */ #define CHUNK 1024 /* how much to read at once */ #define NULL 0 /* Hack some new baud rates for Minix. Minix uses a divide-by-100 encoding. */ #define B200 2 #define B600 6 #define B1800 18 #define B3600 36 #define B7200 72 #define B19200 192 #define EXTA 192 /* We can't handle some standard (slow) V7 speeds and speeds above 25500 since * since the speed is packed into a char :-(. Trap them with an illegal value. */ #define B50 0 #define B75 0 #define B134 0 #define EXTB 0 #define B38400 0 #define B57600 0 #define B115200 0 int commfd; /* open file no. for comm device */ int readpid; /* pid of child reading commfd */ struct sgttyb sgcommfd; /* saved terminal parameters for commfd */ struct sgttyb sgstdin; /* saved terminal parameters for stdin */ int writepid; /* pid of child writing commfd */ #if (MACHINE == ATARI) char endseq[] = "Ou"; /* sequence to leave simulator */ #else char endseq[] = "\033[G"; /* sequence to leave simulator */ #endif /* Keypad '5', and must arrive in 1 piece */ struct param_s { char *pattern; int value; char type; #define BAD 0 #define BITS 1 #define NOSTRIP 2 #define PARITY 3 #define SPEED 4 } params[] = { "5", BITS5, BITS, "6", BITS6, BITS, "7", BITS7, BITS, "8", BITS8, BITS, "even", EVENP, PARITY, "odd", ODDP, PARITY, "nostrip", 0, NOSTRIP, "50", B50, SPEED, "75", B75, SPEED, "110", B110, SPEED, "134", B134, SPEED, "200", B200, SPEED, "300", B300, SPEED, "600", B600, SPEED, "1200", B1200, SPEED, "1800", B1800, SPEED, "2400", B2400, SPEED, "3600", B3600, SPEED, "4800", B4800, SPEED, "7200", B7200, SPEED, "9600", B9600, SPEED, "19200", B19200, SPEED, "EXTA", EXTA, SPEED, "EXTB", EXTB, SPEED, "38400", B38400, SPEED, "57600", B57600, SPEED, "115200", B115200, SPEED, "", 0, BAD, /* BAD type to end list */ }; unsigned char strip_parity = 1; /* nonzero to strip high bits before output */ int quit(); /* forward declare signal handler */ main(argc, argv) int argc; char *argv[]; { char *commdev = NULL; int i; int pipefd[2]; sync(); for (i = 1; i < argc; ++i) if (argv[i][0] == '/') { if (commdev != NULL) error("Too many communication devices", ""); commdev = argv[i]; } if (commdev == NULL) { i = MAXARGS + 1; commdev = "/dev/tty1"; } else i = MAXARGS + 2; if (argc > i) error("Usage: term [baudrate] [data_bits] [parity]", ""); commfd = open(commdev, O_RDWR); if (commfd < 0) error("Can't open ", commdev); /* Save state of both devices before altering either (may be identical!). */ ioctl(0, TIOCGETP, &sgstdin); ioctl(commfd, TIOCGETP, &sgcommfd); set_mode(0, -1, -1, -1, &sgstdin); /* RAW mode on stdin, others * current */ set_uart(argc, argv); /* Main body of the terminal simulator. */ signal(SIGINT, quit); signal(SIGPIPE, quit); if (pipe(pipefd) < 0) error("Can't create pipe", ""); switch ((writepid = fork())) { case -1: error("Can't create process to write to comm device", ""); case 0: /* Piped stdin to tty */ close(pipefd[1]); copy(pipefd[0], "piped stdin", commfd, commdev, ""); } close(pipefd[0]); switch ((readpid = fork())) { case -1: error("Can't create process to read from comm device", ""); case 0: /* Tty to stdout */ copy(commfd, commdev, 1, "stdout", ""); } /* Stdin to pipe */ copy(0, "stdin", pipefd[1], "redirect stdin", endseq); } set_uart(argc, argv) int argc; char *argv[]; { /* Set up the UART parameters. */ int i, j, bits, nbits, parity, nparities, speed, nspeeds; char *arg; register struct param_s *param; /* Examine all the parameters and check for validity. */ nspeeds = nparities = nbits = 0; speed = parity = bits = -1; /* -1 means use current value */ for (i = 1; i < argc; ++i) { if ((arg = argv[i])[0] == '/') continue; /* Check parameter for legality. */ for (j = 0, param = ¶ms[0]; param->type != BAD && strcmp(arg, param->pattern) != 0; ++j, ++param); switch (param->type) { case BAD: error("Invalid parameter: ", arg); case BITS: bits = param->value; if (++nbits > 1) error("Too many character sizes", ""); break; case PARITY: parity = param->value; if (++nparities > 1) error("Too many parities", ""); break; case SPEED: speed = param->value; if (speed == 0) error("Invalid speed: ", arg); if (++nspeeds > 1) error("Too many speeds", ""); break; case NOSTRIP: strip_parity = 0; break; } } set_mode(commfd, speed, parity, bits, &sgcommfd); } set_mode(fd, speed, parity, bits, sgsavep) int speed; int parity; int bits; struct sgttyb *sgsavep; { /* Set open file fd to RAW mode with the given other modes. If fd is * not a tty, this may do nothing but connecting ordinary files as * ttys may have some use. */ struct sgttyb sgtty; int tabs; sgtty = *sgsavep; tabs = sgtty.sg_flags & XTABS; if (speed == -1) speed = sgtty.sg_ispeed; if (parity == -1) parity = sgtty.sg_flags & (EVENP | ODDP); if (bits == -1) bits = sgtty.sg_flags & BITS8; /* BITS8 is actually a mask */ sgtty.sg_ispeed = speed; sgtty.sg_ospeed = speed; sgtty.sg_flags = RAW | parity | bits | tabs; ioctl(fd, TIOCSETP, &sgtty); } copy(in, inname, out, outname, end) int in; char *inname; int out; char *outname; char *end; { /* Copy from one open file to another. If the 'end' sequence is not "", and * precisely matches the input, terminate the copy and various children. * The end sequence is best provided by keyboard input from one of the * special keys which always produces chars in a bunch. RAW mode almost * guarantees exactly one keystroke's worth of input at a time. */ static char buf[CHUNK]; char *bufend; register char *bufp; int count; int len; len = strlen(end); while (1) { if ((count = read(in, buf, CHUNK)) <= 0) { write2sn("Can't read from ", inname); quit(); } if (count == len && strncmp(buf, end, count) == 0) quit(); if (strip_parity) for (bufp = buf, bufend = bufp + count; bufp < bufend; ++bufp) *bufp &= 0x7F; if (write(out, buf, count) != count) { write2sn("Can't write to ", outname); quit(); } } } error(s1, s2) char *s1; char *s2; { write2sn(s1, s2); exit(1); } nicequit() { exit(0); } quit() { ioctl(commfd, TIOCSETP, &sgcommfd); ioctl(0, TIOCSETP, &sgstdin); signal(SIGINT, nicequit); /* if not caught, sh prints extra newline */ kill(0, SIGINT); nicequit(); } write2sn(s1, s2) { write(1, s1, strlen(s1)); write(1, s2, strlen(s2)); write(1, "\r\n", 2); }