/*      @(#)ttoutput.c  8.1 (Berkeley) 6/6/93   */
/*      $NetBSD: ttoutput.c,v 1.9 2009/04/14 08:50:06 lukem Exp $       */

/*
 * Copyright (c) 1983, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Edward Wang at The University of California, Berkeley.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include <errno.h>
#include <string.h>
#include <unistd.h>
#include "ww.h"
#include "tt.h"

/*
 * Buffered output package.
 * We need this because stdio fails on non-blocking writes.
 */

void
ttflush(void)
{
        char *p;
        int n = tt_obp - tt_ob;

        if (n == 0)
                return;
        if (tt.tt_checksum)
                (*tt.tt_checksum)(tt_ob, n);
        if (tt.tt_flush) {
                (*tt.tt_flush)();
                return;
        }
        wwnflush++;
        for (p = tt_ob; p < tt_obp;) {
                wwnwr++;
                n = write(1, p, tt_obp - p);
                if (n < 0) {
                        wwnwre++;
                        if (errno != EWOULDBLOCK) {
                                /* can't deal with this */
                                p = tt_obp;
                        }
                } else if (n == 0) {
                        /* what to do? */
                        wwnwrz++;
                } else {
                        wwnwrc += n;
                        p += n;
                }
        }
        tt_obp = tt_ob;
}

void
ttputs(const char *s)
{
        while (*s)
                ttputc(*s++);
}

void
ttwrite(const char *s, int n)
{
        switch (n) {
        case 0:
                break;
        case 1:
                ttputc(*s);
                break;
        case 2:
                if (tt_obe - tt_obp < 2)
                        ttflush();
                *tt_obp++ = *s++;
                *tt_obp++ = *s;
                break;
        case 3:
                if (tt_obe - tt_obp < 3)
                        ttflush();
                *tt_obp++ = *s++;
                *tt_obp++ = *s++;
                *tt_obp++ = *s;
                break;
        case 4:
                if (tt_obe - tt_obp < 4)
                        ttflush();
                *tt_obp++ = *s++;
                *tt_obp++ = *s++;
                *tt_obp++ = *s++;
                *tt_obp++ = *s;
                break;
        case 5:
                if (tt_obe - tt_obp < 5)
                        ttflush();
                *tt_obp++ = *s++;
                *tt_obp++ = *s++;
                *tt_obp++ = *s++;
                *tt_obp++ = *s++;
                *tt_obp++ = *s;
                break;
        default:
                while (n > 0) {
                        int m;

                        while ((m = tt_obe - tt_obp) == 0)
                                ttflush();
                        if ((m = tt_obe - tt_obp) > n)
                                m = n;
                        memmove(tt_obp, s, m);
                        tt_obp += m;
                        s += m;
                        n -= m;
                }
        }
}