inline int linenoiseEdit()

in DroneShell/include/linenoise.hpp [3608:3789]


inline int linenoiseEdit(int stdin_fd, int stdout_fd, char* buf, size_t buflen, const char* prompt)
{
    struct linenoiseState l;

    /* Populate the linenoise state that we pass to functions implementing
    * specific editing functionalities. */
    l.ifd = stdin_fd;
    l.ofd = stdout_fd;
    l.buf = buf;
    l.buflen = buflen;
    l.prompt = prompt;
    l.oldcolpos = l.pos = 0;
    l.len = 0;
    l.cols = getColumns(stdin_fd, stdout_fd);
    l.maxrows = 0;
    l.history_index = 0;

    /* Buffer starts empty. */
    l.buf[0] = '\0';
    l.buflen--; /* Make sure there is always space for the nulterm */

    /* The latest history entry is always our current buffer, that
                * initially is just an empty string. */
    AddHistory("");

    if (write(l.ofd, prompt, l.prompt.length()) == -1) return -1;
    while (1) {
        int c;
        char cbuf[4];
        int nread;
        char seq[3];

#ifdef _WIN32
        nread = win32read(&c);
        if (nread == 1) {
            cbuf[0] = c;
        }
#else
        nread = unicodeReadUTF8Char(l.ifd, cbuf, &c);
#endif
        if (nread <= 0) return (int)l.len;

        /* Only autocomplete when the callback is set. It returns < 0 when
        * there was an error reading from fd. Otherwise it will return the
        * character that should be handled next. */
        if (c == 9 && completionCallback != NULL) {
            nread = completeLine(&l, cbuf, &c);
            /* Return on errors */
            if (c < 0) return l.len;
            /* Read next character when 0 */
            if (c == 0) continue;
        }

        switch (c) {
        case ENTER: /* enter */
            history.pop_back();
            if (mlmode) linenoiseEditMoveEnd(&l);
            return (int)l.len;
        case CTRL_C: /* ctrl-c */
            errno = EAGAIN;
            return -1;
        case BACKSPACE: /* backspace */
        case 8: /* ctrl-h */
            linenoiseEditBackspace(&l);
            break;
        case CTRL_D: /* ctrl-d, remove char at right of cursor, or if the
                         line is empty, act as end-of-file. */
            if (l.len > 0) {
                linenoiseEditDelete(&l);
            }
            else {
                history.pop_back();
                return -1;
            }
            break;
        case CTRL_T: /* ctrl-t, swaps current character with previous. */
            if (l.pos > 0 && l.pos < l.len) {
                int aux = buf[l.pos - 1];
                buf[l.pos - 1] = buf[l.pos];
                buf[l.pos] = aux;
                if (l.pos != l.len - 1) l.pos++;
                refreshLine(&l);
            }
            break;
        case CTRL_B: /* ctrl-b */
            linenoiseEditMoveLeft(&l);
            break;
        case CTRL_F: /* ctrl-f */
            linenoiseEditMoveRight(&l);
            break;
        case CTRL_P: /* ctrl-p */
            linenoiseEditHistoryNext(&l, LINENOISE_HISTORY_PREV);
            break;
        case CTRL_N: /* ctrl-n */
            linenoiseEditHistoryNext(&l, LINENOISE_HISTORY_NEXT);
            break;
        case ESC: /* escape sequence */
            /* Read the next two bytes representing the escape sequence.
                     * Use two calls to handle slow terminals returning the two
                     * chars at different times. */
            if (read(l.ifd, seq, 1) == -1) break;
            if (read(l.ifd, seq + 1, 1) == -1) break;

            /* ESC [ sequences. */
            if (seq[0] == '[') {
                if (seq[1] >= '0' && seq[1] <= '9') {
                    /* Extended escape, read additional byte. */
                    if (read(l.ifd, seq + 2, 1) == -1) break;
                    if (seq[2] == '~') {
                        switch (seq[1]) {
                        case '3': /* Delete key. */
                            linenoiseEditDelete(&l);
                            break;
                        }
                    }
                }
                else {
                    switch (seq[1]) {
                    case 'A': /* Up */
                        linenoiseEditHistoryNext(&l, LINENOISE_HISTORY_PREV);
                        break;
                    case 'B': /* Down */
                        linenoiseEditHistoryNext(&l, LINENOISE_HISTORY_NEXT);
                        break;
                    case 'C': /* Right */
                        linenoiseEditMoveRight(&l);
                        break;
                    case 'D': /* Left */
                        linenoiseEditMoveLeft(&l);
                        break;
                    case 'H': /* Home */
                        linenoiseEditMoveHome(&l);
                        break;
                    case 'F': /* End*/
                        linenoiseEditMoveEnd(&l);
                        break;
                    }
                }
            }

            /* ESC O sequences. */
            else if (seq[0] == 'O') {
                switch (seq[1]) {
                case 'H': /* Home */
                    linenoiseEditMoveHome(&l);
                    break;
                case 'F': /* End*/
                    linenoiseEditMoveEnd(&l);
                    break;
                }
            }
            break;
        default:
            if (linenoiseEditInsert(&l, cbuf, nread)) return -1;
            break;
        case CTRL_U: /* Ctrl+u, delete the whole line. */
            buf[0] = '\0';
            l.pos = l.len = 0;
            refreshLine(&l);
            break;
        case CTRL_K: /* Ctrl+k, delete from current to end of line. */
            buf[l.pos] = '\0';
            l.len = l.pos;
            refreshLine(&l);
            break;
        case CTRL_A: /* Ctrl+a, go to the start of the line */
            linenoiseEditMoveHome(&l);
            break;
        case CTRL_E: /* ctrl+e, go to the end of the line */
            linenoiseEditMoveEnd(&l);
            break;
        case CTRL_L: /* ctrl+l, clear screen */
            linenoiseClearScreen();
            refreshLine(&l);
            break;
        case CTRL_W: /* ctrl+w, delete previous word */
            linenoiseEditDeletePrevWord(&l);
            break;
        }
    }
    return l.len;
}