source: trunk/software/tty/readtty_timer.c @ 14

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <err.h>
#include <fcntl.h>
#include <signal.h>
#include <string.h>
#include <termios.h>
#include <sys/ioctl.h>
#include <sys/select.h>

volatile int quit;

static void
set_quit(int s)
{
        quit = 1;
}

static void
readline(int d, char *buf, int l)
{
        int i;
        int bytes;
        do {
                for (i = 0; i < l; i++) {
                        do {
                                bytes = read(d, &buf[i], 1);
                                if (quit)
                                        return;
                        } while ((bytes < 0 && errno == EAGAIN) || buf[i] == '\r');
                        if (bytes != 1) {
                                fprintf(stderr, "readline: read %d\n", bytes);
                                err(1, "read line");
                        }
                        if (buf[i] == '\n')
                                break;
                }
        } while (i == 0);
        if (buf[i] != '\n') {
                errx(1, "realine: end of line not found");
        }
        buf[i] = '\0';
}

int
main(int argc, const char *argv[])
{
        int d;
        int bytes;
        int nfds;
        char buf[256];
        int i;
        fd_set rfds;
        char gpio[3], current[4], tension[4];
        char *endp;
        int gpioi, currenti, tensioni;
        int gpioval, currentval, tensionval;
        int exitst = 0;

        enum {
                INIT,
                GPIO,
                CURRENT,
                TENSION,
                MARK
        } state;

        struct termios t, ot;

        state = INIT;
        gpioi = currenti = tensioni = 0;

        if (argc != 3) {
                errx(1, "usage: %s <device> time", argv[0]);
        }

        d = open(argv[1], O_RDWR | O_NOCTTY | O_NONBLOCK, 0);
        if (d < 0) {
                err(1, "open %s", argv[1]);
        }
        fprintf(stderr, "o\n");

        if (tcgetattr(d, &ot) < 0) {
                err(1, "tcgetattr");
        }
        fprintf(stderr, "tg\n");

        quit = 0;

        if (signal(SIGINT, set_quit) == SIG_ERR) {
                err(1, "signal(SIGINT)");
        }
        if (signal(SIGQUIT, set_quit) == SIG_ERR) {
                err(1, "signal(SIGQUIT)");
        }
        if (signal(SIGPIPE, set_quit) == SIG_ERR) {
                err(1, "signal(SIGPIPE)");
        }
        if (signal(SIGTERM, set_quit) == SIG_ERR) {
                err(1, "signal(SIGTERM)");
        }

        if (signal(SIGALRM, set_quit) == SIG_ERR) {
                err(1, "signal(SIGALRM)");
        }

        t = ot;
        cfmakeraw(&t);
        t.c_cflag |= CLOCAL;
        t.c_cflag &= ~CRTSCTS;
        cfsetspeed(&t, B921600);

        if (tcsetattr(d, TCSANOW | TCSAFLUSH, &t) < 0) {
                err(1, "tcsetattr");
        }
        fprintf(stderr, "tty ready\n");
        write(d, "M0\n", 3);
        write(d, "M0\n", 3);
        do {
                readline(d, buf, sizeof(buf));
                if (quit)
                        goto quit;
        } while (memcmp(buf, "OK", 2) != 0);
        fprintf(stderr, "starting\n");
        write(d, "M1\n", 3);

        alarm(atoi(argv[2]));
        FD_ZERO(&rfds);
        while (quit == 0) {
                FD_SET(d, &rfds);
                nfds = select(d+1, &rfds, NULL, NULL, NULL);
                if (nfds > 0 && FD_ISSET(d, &rfds)) {
                        bytes = read(d, buf, sizeof(buf));
                        if (bytes > sizeof(buf)) {
                                errx(1, "read %d/0x%x bytes", bytes, bytes);
                        }
                        if (bytes < 0 && errno != EAGAIN) {
                                warn("read");
                                continue;
                        }
                        for (i = 0; i < bytes; i++) {
                                if (i > sizeof(buf))
                                        abort();
                                if (bytes > sizeof(buf))
                                        abort();
                                if (gpioi > sizeof(buf))
                                        abort();
                                if (tensioni > sizeof(buf))
                                        abort();
                                if (currenti > sizeof(buf))
                                        abort();
                                switch(state) {
                                case INIT:
                                        /* look for an X mark */
                                        if (buf[i] == 'X') {
                                                state = GPIO;
                                                gpioi = 0;
                                        }
                                        break;
                                case GPIO:
                                        gpio[gpioi] = buf[i];
                                        gpioi++;
                                        if (gpioi < 2)
                                                break;
                                        gpio[gpioi] = '\0';
                                        gpioval = strtol(gpio, &endp, 16);
                                        if (*endp != '\0') {
                                                fprintf(stderr,
                                                    "gpio error: %c\n",
                                                    *endp);
                                                exitst = 1;
                                                state = INIT;
                                        } else {
                                                state = TENSION;
                                                tensioni = 0;
                                        }
                                        break;
                                case CURRENT:
                                        current[currenti] = buf[i];
                                        currenti++;
                                        if (currenti < 3)
                                                break;
                                        current[currenti] = '\0';
                                        currentval = strtol(current, &endp, 16);
                                        if (*endp != '\0') {
                                                fprintf(stderr,
                                                    "current error: %c\n",
                                                    *endp);
                                                exitst = 1;
                                                state = INIT;
                                        } else {
                                                state = MARK;
                                                tensioni = 0;
                                        }
                                        break;
                                case TENSION:
                                        tension[tensioni] = buf[i];
                                        tensioni++;
                                        if (tensioni < 3)
                                                break;
                                        tension[tensioni] = '\0';
                                        tensionval = strtol(tension, &endp, 16);
                                        if (*endp != '\0') {
                                                fprintf(stderr,
                                                    "tension error: %c\n",
                                                    *endp);
                                                exitst = 1;
                                                state = INIT;
                                        } else {
                                                state = CURRENT;
                                                currenti = 0;
                                        }
                                        break;
                                case MARK:
                                        if (buf[i] != 'X') {
                                                fprintf(stderr,
                                                    "mark error: %c\n",
                                                    buf[i]);
                                                exitst = 1;
                                                state = INIT;
                                        } else {
                                                printf("%3d ", gpioval);
                                                printf("%4d ", tensionval);
                                                printf("%4d\n", currentval);
                                                state = GPIO;
                                                gpioi = 0;
                                        }
                                        break;
                                }
                        }
                } else if (nfds < 0) {
                        warn("select");
                }
        }
quit:
        /* stop measures */
        write(d, "M0\n", 3);
        if (fflush(stdout) == EOF) {  
                warn("fflush");       
        }

        if (tcsetattr(d, TCSANOW, &ot) < 0) {
                err(1, "restore tcsetattr");
        }
        exit(exitst);
}