_dopr(char **sbuffer,
      char **buffer,
      size_t *maxlen,
      size_t *retlen, int *truncated, const char *format, va_list args)
{
    char ch;
    LLONG value;
    LDOUBLE fvalue;
    char *strvalue;
    int min;
    int max;
    int state;
    int flags;
    int cflags;
    size_t currlen;

    state = DP_S_DEFAULT;
    flags = currlen = cflags = min = 0;
    max = -1;
    ch = *format++;

    while (state != DP_S_DONE) {
        if (ch == '\0' || (buffer == NULL && currlen >= *maxlen))
            state = DP_S_DONE;

        switch (state) {
        case DP_S_DEFAULT:
            if (ch == '%')
                state = DP_S_FLAGS;
            else
                if(!doapr_outch(sbuffer, buffer, &currlen, maxlen, ch))
                    return 0;
            ch = *format++;
            break;
        case DP_S_FLAGS:
            switch (ch) {
            case '-':
                flags |= DP_F_MINUS;
                ch = *format++;
                break;
            case '+':
                flags |= DP_F_PLUS;
                ch = *format++;
                break;
            case ' ':
                flags |= DP_F_SPACE;
                ch = *format++;
                break;
            case '#':
                flags |= DP_F_NUM;
                ch = *format++;
                break;
            case '0':
                flags |= DP_F_ZERO;
                ch = *format++;
                break;
            default:
                state = DP_S_MIN;
                break;
            }
            break;
        case DP_S_MIN:
            if (isdigit((unsigned char)ch)) {
                min = 10 * min + char_to_int(ch);
                ch = *format++;
            } else if (ch == '*') {
                min = va_arg(args, int);
                ch = *format++;
                state = DP_S_DOT;
            } else
                state = DP_S_DOT;
            break;
        case DP_S_DOT:
            if (ch == '.') {
                state = DP_S_MAX;
                ch = *format++;
            } else
                state = DP_S_MOD;
            break;
        case DP_S_MAX:
            if (isdigit((unsigned char)ch)) {
                if (max < 0)
                    max = 0;
                max = 10 * max + char_to_int(ch);
                ch = *format++;
            } else if (ch == '*') {
                max = va_arg(args, int);
                ch = *format++;
                state = DP_S_MOD;
            } else
                state = DP_S_MOD;
            break;
        case DP_S_MOD:
            switch (ch) {
            case 'h':
                cflags = DP_C_SHORT;
                ch = *format++;
                break;
            case 'l':
                if (*format == 'l') {
                    cflags = DP_C_LLONG;
                    format++;
                } else
                    cflags = DP_C_LONG;
                ch = *format++;
                break;
            case 'q':
                cflags = DP_C_LLONG;
                ch = *format++;
                break;
            case 'L':
                cflags = DP_C_LDOUBLE;
                ch = *format++;
                break;
            default:
                break;
            }
            state = DP_S_CONV;
            break;
        case DP_S_CONV:
            switch (ch) {
            case 'd':
            case 'i':
                switch (cflags) {
                case DP_C_SHORT:
                    value = (short int)va_arg(args, int);
                    break;
                case DP_C_LONG:
                    value = va_arg(args, long int);
                    break;
                case DP_C_LLONG:
                    value = va_arg(args, LLONG);
                    break;
                default:
                    value = va_arg(args, int);
                    break;
                }
                if (!fmtint(sbuffer, buffer, &currlen, maxlen, value, 10, min,
                            max, flags))
                    return 0;
                break;
            case 'X':
                flags |= DP_F_UP;
                /* FALLTHROUGH */
            case 'x':
            case 'o':
            case 'u':
                flags |= DP_F_UNSIGNED;
                switch (cflags) {
                case DP_C_SHORT:
                    value = (unsigned short int)va_arg(args, unsigned int);
                    break;
                case DP_C_LONG:
                    value = (LLONG) va_arg(args, unsigned long int);
                    break;
                case DP_C_LLONG:
                    value = va_arg(args, unsigned LLONG);
                    break;
                default:
                    value = (LLONG) va_arg(args, unsigned int);
                    break;
                }
                if (!fmtint(sbuffer, buffer, &currlen, maxlen, value,
                            ch == 'o' ? 8 : (ch == 'u' ? 10 : 16),
                            min, max, flags))
                    return 0;
                break;
            case 'f':
                if (cflags == DP_C_LDOUBLE)
                    fvalue = va_arg(args, LDOUBLE);
                else
                    fvalue = va_arg(args, double);
                if (!fmtfp(sbuffer, buffer, &currlen, maxlen, fvalue, min, max,
                           flags))
                    return 0;
                break;
            case 'E':
                flags |= DP_F_UP;
            case 'e':
                if (cflags == DP_C_LDOUBLE)
                    fvalue = va_arg(args, LDOUBLE);
                else
                    fvalue = va_arg(args, double);
                break;
            case 'G':
                flags |= DP_F_UP;
            case 'g':
                if (cflags == DP_C_LDOUBLE)
                    fvalue = va_arg(args, LDOUBLE);
                else
                    fvalue = va_arg(args, double);
                break;
            case 'c':
                if(!doapr_outch(sbuffer, buffer, &currlen, maxlen,
                            va_arg(args, int)))
                    return 0;
                break;
            case 's':
                strvalue = va_arg(args, char *);
                if (max < 0) {
                    if (buffer)
                        max = INT_MAX;
                    else
                        max = *maxlen;
                }
                if (!fmtstr(sbuffer, buffer, &currlen, maxlen, strvalue,
                            flags, min, max))
                    return 0;
                break;
            case 'p':
                value = (long)va_arg(args, void *);
                if (!fmtint(sbuffer, buffer, &currlen, maxlen,
                            value, 16, min, max, flags | DP_F_NUM))
                    return 0;
                break;
            case 'n':          /* XXX */
                if (cflags == DP_C_SHORT) {
                    short int *num;
                    num = va_arg(args, short int *);
                    *num = currlen;
                } else if (cflags == DP_C_LONG) { /* XXX */
                    long int *num;
                    num = va_arg(args, long int *);
                    *num = (long int)currlen;
                } else if (cflags == DP_C_LLONG) { /* XXX */
                    LLONG *num;
                    num = va_arg(args, LLONG *);
                    *num = (LLONG) currlen;
                } else {
                    int *num;
                    num = va_arg(args, int *);
                    *num = currlen;
                }
                break;
            case '%':
                if(!doapr_outch(sbuffer, buffer, &currlen, maxlen, ch))
                    return 0;
                break;
            case 'w':
                /* not supported yet, treat as next char */
                ch = *format++;
                break;
            default:
                /* unknown, skip */
                break;
            }
            ch = *format++;
            state = DP_S_DEFAULT;
            flags = cflags = min = 0;
            max = -1;
            break;
        case DP_S_DONE:
            break;
        default:
            break;
        }
    }
    *truncated = (currlen > *maxlen - 1);
    if (*truncated)
        currlen = *maxlen - 1;
    if(!doapr_outch(sbuffer, buffer, &currlen, maxlen, '\0'))
        return 0;
    *retlen = currlen - 1;
    return 1;
}