diff options
| -rw-r--r-- | miscutils/microcom.c | 153 |
1 files changed, 71 insertions, 82 deletions
diff --git a/miscutils/microcom.c b/miscutils/microcom.c index 00a4983..fb5e9c8 100644 --- a/miscutils/microcom.c +++ b/miscutils/microcom.c @@ -17,7 +17,7 @@ static void signal_handler(int signo) signalled = signo; } -// set canonical tty mode +// set raw tty mode static void xget1(int fd, struct termios *t, struct termios *oldt) { tcgetattr(fd, oldt); @@ -32,7 +32,7 @@ static void xget1(int fd, struct termios *t, struct termios *oldt) static int xset1(int fd, struct termios *tio, const char *device) { - int ret = tcsetattr(fd, TCSANOW, tio); + int ret = tcsetattr(fd, TCSAFLUSH, tio); if (ret) { bb_perror_msg("can't tcsetattr for %s", device); @@ -43,41 +43,45 @@ static int xset1(int fd, struct termios *tio, const char *device) int microcom_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; int microcom_main(int argc, char **argv) { - struct pollfd pfd[2]; - int nfd; int sfd; -/* #define sfd (pfd[0].fd) - gcc 4.2.1 is still not smart enough */ - char *device_lock_file; - const char *opt_s = "9600"; - speed_t speed; - const char *opt_t = "100"; // 0.1 sec timeout - unsigned timeout; + int nfd; + struct pollfd pfd[2]; struct termios tio0, tiosfd, tio; - bool istty; + char *device_lock_file; + enum { + OPT_X = 1 << 0, // do not respect Ctrl-X, Ctrl-@ + OPT_s = 1 << 1, // baudrate + OPT_t = 1 << 2 // wait for device response, msecs + }; + speed_t speed = 9600; + int timeout = 100; // 0.1 sec timeout // fetch options - opt_complementary = "-1"; /* at least one arg should be there */ - getopt32(argv, "s:t:", &opt_s, &opt_t); - argc -= optind; + char *opt_s; + char *opt_t; + unsigned opts; + opt_complementary = "=1"; /* exactly one arg should be there */ + opts = getopt32(argv, "Xs:t:", &opt_s, &opt_t); + // apply options + if (opts & OPT_s) + speed = xatoi_u(opt_s); + if (opts & OPT_t) + timeout = xatoi_u(opt_t); +// argc -= optind; argv += optind; - // check sanity - speed = xatou(opt_s); - timeout = xatou(opt_t); - device_lock_file = (char *)bb_basename(argv[0]); - // try to create lock file in /var/lock + device_lock_file = (char *)bb_basename(argv[0]); device_lock_file = xasprintf("/var/lock/LCK..%s", device_lock_file); sfd = open(device_lock_file, O_CREAT | O_WRONLY | O_TRUNC | O_EXCL, 0644); if (sfd < 0) { if (errno == EEXIST) - bb_perror_msg_and_die("can't lock device"); - // We don't abort on other errors: /var/lock can be - // non-writable or non-existent + bb_perror_msg_and_die("can't create %s", device_lock_file); if (ENABLE_FEATURE_CLEAN_UP) free(device_lock_file); device_lock_file = NULL; - } else { + } + if (sfd > 0) { // %4d to make mgetty happy. It treats 4-bytes lock files as binary, // not text, PID. Making 5+ char file. Brrr... char *s = xasprintf("%4d\n", getpid()); @@ -99,17 +103,15 @@ int microcom_main(int argc, char **argv) // open device sfd = open_or_warn(argv[0], O_RDWR | O_NOCTTY | O_NONBLOCK); if (sfd < 0) - goto unlock_and_exit; + goto done; fcntl(sfd, F_SETFL, O_RDWR | O_NOCTTY); /* put stdin to "raw mode" (if stdin is a TTY), handle one character at a time */ - istty = isatty(STDIN_FILENO); - if (istty) { + if (isatty(STDIN_FILENO)) { xget1(STDIN_FILENO, &tio, &tio0); if (xset1(STDIN_FILENO, &tio, "stdin")) - goto close_unlock_and_exit; -// tcflush(STDIN_FILENO, TCIFLUSH); + goto done; timeout = -1; // tty input? -> set infinite timeout for poll() } @@ -117,10 +119,12 @@ int microcom_main(int argc, char **argv) xget1(sfd, &tio, &tiosfd); // order device to hang up at exit tio.c_cflag |= (CREAD|HUPCL); +// if (!istty) +// tio.c_iflag |= (IGNCR); // set device speed cfsetspeed(&tio, tty_value_to_baud(speed)); if (xset1(sfd, &tio, argv[0])) - goto restore0_close_unlock_and_exit; + goto restore0_and_done; // main loop: check with poll(), then read/write bytes across pfd[0].fd = sfd; @@ -128,69 +132,54 @@ int microcom_main(int argc, char **argv) pfd[1].fd = STDIN_FILENO; pfd[1].events = POLLIN; - // TODO: on piped input should we treat NL as CRNL?! - signalled = 0; - // initially we have to poll() both stdin and device nfd = 2; - while (!signalled && nfd && safe_poll(pfd, nfd, timeout) > 0) { - int i; - - for (i = 0; i < nfd; ++i) { - if (pfd[i].revents & (POLLIN | POLLHUP)) { -// int fd; - char c; - // read a byte - if (safe_read(pfd[i].fd, &c, 1) < 1) { - // this can occur at the end of piped input - // from now we only poll() for device - nfd--; + while (!signalled && safe_poll(pfd, nfd, timeout) > 0) { + char c; + if (pfd[0].revents & POLLIN) { + // read from device -> write to stdout + if (safe_read(sfd, &c, 1) > 0) + write(STDOUT_FILENO, &c, 1); + } + if (pfd[1].revents & POLLIN) { + // read from stdin -> write to device + if (safe_read(STDIN_FILENO, &c, 1) < 1) { + // skip polling stdin if we got EOF/error + pfd[1].revents = 0; + nfd--; + continue; + } + // do we need special processing? + if (!(opts & OPT_X)) { + // ^@ sends Break + if (VINTR == c) { + tcsendbreak(sfd, 0); continue; } -// fd = STDOUT_FILENO; - // stdin requires additional processing - // (TODO: must be controlled by command line switch) - if (i) { - // ^@ sends Break - if (0 == c) { - tcsendbreak(sfd, 0); - continue; - } - // ^X exits - if (24 == c) - goto done; -// fd = sfd; - } - // write the byte - write(i ? sfd : STDOUT_FILENO, &c, 1); -// write(fd, &c, 1); - // give device a chance to get data - // wait 0.01 msec - // (TODO: seems to be arbitrary to me) - if (i) - usleep(10); + // ^X exits + if (24 == c) + break; } + write(sfd, &c, 1); +//// vda: this is suspicious! + // without this we never get POLLIN on sfd + // until piped stdin is drained + if (-1 != timeout) + safe_poll(pfd, 1, 1 /* 1 ms */); } } -done: - tcsetattr(sfd, TCSANOW, &tiosfd); + /* usleep(10000); - let last chars leave serial line */ -restore0_close_unlock_and_exit: - if (istty) { -// tcflush(STDIN_FILENO, TCIFLUSH); - tcsetattr(STDIN_FILENO, TCSANOW, &tio0); - } + tcsetattr(sfd, TCSAFLUSH, &tiosfd); -close_unlock_and_exit: - if (ENABLE_FEATURE_CLEAN_UP) - close(sfd); +restore0_and_done: + // timeout == -1 -- stdin is a tty + if (-1 == timeout) + tcsetattr(STDIN_FILENO, TCSAFLUSH, &tio0); -unlock_and_exit: - // delete lock file - if (device_lock_file) { +done: + if (device_lock_file) unlink(device_lock_file); - if (ENABLE_FEATURE_CLEAN_UP) - free(device_lock_file); - } + return signalled; } |