Ejemplo n.º 1
0
/**
 * Stores the current cursor column in '*cols'.
 * Returns 1 if OK, or 0 if failed to determine cursor pos.
 */
static int queryCursor(int fd, int* cols)
{
    /* control sequence - report cursor location */
    fd_printf(fd, "\x1b[6n");

    /* Parse the response: ESC [ rows ; cols R */
    if (fd_read_char(fd, 100) == 0x1b &&
        fd_read_char(fd, 100) == '[') {

        int n = 0;
        while (1) {
            int ch = fd_read_char(fd, 100);
            if (ch == ';') {
                /* Ignore rows */
                n = 0;
            }
            else if (ch == 'R') {
                /* Got cols */
                if (n != 0 && n < 1000) {
                    *cols = n;
                }
                break;
            }
            else if (ch >= 0 && ch <= '9') {
                n = n * 10 + ch - '0';
            }
            else {
                break;
            }
        }
        return 1;
    }

    return 0;
}
Ejemplo n.º 2
0
/**
 * If escape (27) was received, reads subsequent
 * chars to determine if this is a known special key.
 *
 * Returns SPECIAL_NONE if unrecognised, or -1 if EOF.
 *
 * If no additional char is received within a short time,
 * 27 is returned.
 */
static int check_special(int fd)
{
    int c = fd_read_char(fd, 50);
    int c2;

    if (c < 0) {
        return 27;
    }

    c2 = fd_read_char(fd, 50);
    if (c2 < 0) {
        return c2;
    }
    if (c == '[' || c == 'O') {
        /* Potential arrow key */
        switch (c2) {
            case 'A':
                return SPECIAL_UP;
            case 'B':
                return SPECIAL_DOWN;
            case 'C':
                return SPECIAL_RIGHT;
            case 'D':
                return SPECIAL_LEFT;
            case 'F':
                return SPECIAL_END;
            case 'H':
                return SPECIAL_HOME;
        }
    }
    if (c == '[' && c2 >= '1' && c2 <= '8') {
        /* extended escape */
        c = fd_read_char(fd, 50);
        if (c == '~') {
            switch (c2) {
                case '2':
                    return SPECIAL_INSERT;
                case '3':
                    return SPECIAL_DELETE;
                case '5':
                    return SPECIAL_PAGE_UP;
                case '6':
                    return SPECIAL_PAGE_DOWN;
                case '7':
                    return SPECIAL_HOME;
                case '8':
                    return SPECIAL_END;
            }
        }
        while (c != -1 && c != '~') {
            /* .e.g \e[12~ or '\e[11;2~   discard the complete sequence */
            c = fd_read_char(fd, 50);
        }
    }

    return SPECIAL_NONE;
}
Ejemplo n.º 3
0
static int getWindowSize(struct current *current)
{
    struct winsize ws;

    if (ioctl(STDOUT_FILENO, TIOCGWINSZ, &ws) == 0 && ws.ws_col != 0) {
        current->cols = ws.ws_col;
        return 0;
    }

    /* Failed to query the window size. Perhaps we are on a serial terminal.
     * Try to query the width by sending the cursor as far to the right
     * and reading back the cursor position.
     * Note that this is only done once per call to linenoise rather than
     * every time the line is refreshed for efficiency reasons.
     */
    if (current->cols == 0) {
        current->cols = 80;

        /* Move cursor far right and report cursor position, then back to the left */
        fd_printf(current->fd, "\x1b[999C" "\x1b[6n");

        /* Parse the response: ESC [ rows ; cols R */
        if (fd_read_char(current->fd, 100) == 0x1b && fd_read_char(current->fd, 100) == '[') {
            int n = 0;
            while (1) {
                int ch = fd_read_char(current->fd, 100);
                if (ch == ';') {
                    /* Ignore rows */
                    n = 0;
                }
                else if (ch == 'R') {
                    /* Got cols */
                    if (n != 0 && n < 1000) {
                        current->cols = n;
                    }
                    break;
                }
                else if (ch >= 0 && ch <= '9') {
                    n = n * 10 + ch - '0';
                }
                else {
                    break;
                }
            }
        }
    }
    return 0;
}
Ejemplo n.º 4
0
/**
 * Reads a complete utf-8 character
 * and returns the unicode value, or -1 on error.
 */
static int fd_read(struct current *current)
{
#ifdef USE_UTF8
    char buf[4];
    int n;
    int i;
    int c;

    if (read(current->fd, &buf[0], 1) != 1) {
        return -1;
    }
    n = utf8_charlen(buf[0]);
    if (n < 1 || n > 3) {
        return -1;
    }
    for (i = 1; i < n; i++) {
        if (read(current->fd, &buf[i], 1) != 1) {
            return -1;
        }
    }
    buf[n] = 0;
    /* decode and return the character */
    utf8_tounicode(buf, &c);
    return c;
#else
    return fd_read_char(current->fd, -1);
#endif
}