/*      $OpenBSD: announce.c,v 1.26 2024/04/28 16:42:53 florian Exp $   */

/*
 * Copyright (c) 1983 Regents of the University of California.
 * All rights reserved.
 *
 * 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 <sys/stat.h>
#include <protocols/talkd.h>

#include <limits.h>
#include <paths.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <vis.h>

#include "talkd.h"

static void     print_mesg(FILE *,CTL_MSG *,char *);

/*
 * Announce an invitation to talk.  If the user is
 * accepting messages, announce that a talk is requested.
 */
int
announce(CTL_MSG *request, char *remote_machine)
{
        char full_tty[PATH_MAX];
        FILE *tf;
        struct stat stbuf;

        (void)snprintf(full_tty, sizeof(full_tty), "%s/%s", _PATH_DEV,
            request->r_tty);
        if (access(full_tty, 0) != 0)
                return (FAILED);
        if ((tf = fopen(full_tty, "w")) == NULL)
                return (PERMISSION_DENIED);
        if (fstat(fileno(tf), &stbuf) == -1) {
                fclose(tf);
                return (PERMISSION_DENIED);
        }
        if ((stbuf.st_mode & S_IWGRP) == 0) {
                fclose(tf);
                return (PERMISSION_DENIED);
        }
        print_mesg(tf, request, remote_machine);
        fclose(tf);
        return (SUCCESS);
}

#define max(a,b) ( (a) > (b) ? (a) : (b) )
#define N_LINES 5
#define N_CHARS 120

/*
 * Build a block of characters containing the message.
 * It is sent blank filled and in a single block to
 * try to keep the message in one piece if the recipient
 * is in vi at the time
 */
static void
print_mesg(FILE *tf, CTL_MSG *request, char *remote_machine)
{
        time_t clocktime;
        struct tm *localclock;
        char line_buf[N_LINES][N_CHARS];
        int sizes[N_LINES];
        char big_buf[(N_LINES + 1) * N_CHARS];
        char *bptr, *lptr, vis_user[sizeof(request->l_name) * 4];
        int i, j, max_size;

        i = 0;
        max_size = 0;
        time(&clocktime);
        localclock = localtime(&clocktime);
        (void)snprintf(line_buf[i], N_CHARS, " ");
        sizes[i] = strlen(line_buf[i]);
        max_size = max(max_size, sizes[i]);
        i++;
        if (localclock) {
                (void)snprintf(line_buf[i], N_CHARS,
                    "Message from Talk_Daemon@%s at %d:%02d ...",
                    hostname, localclock->tm_hour , localclock->tm_min );
        } else {
                (void)snprintf(line_buf[i], N_CHARS,
                    "Message from Talk_Daemon@%s ...", hostname);
        }
        sizes[i] = strlen(line_buf[i]);
        max_size = max(max_size, sizes[i]);
        i++;
        strvis(vis_user, request->l_name, VIS_CSTYLE);
        (void)snprintf(line_buf[i], N_CHARS,
            "talk: connection requested by %s@%s.",
            vis_user, remote_machine);
        sizes[i] = strlen(line_buf[i]);
        max_size = max(max_size, sizes[i]);
        i++;
        (void)snprintf(line_buf[i], N_CHARS, "talk: respond with:  talk %s@%s",
            vis_user, remote_machine);
        sizes[i] = strlen(line_buf[i]);
        max_size = max(max_size, sizes[i]);
        i++;
        (void)snprintf(line_buf[i], N_CHARS, " ");
        sizes[i] = strlen(line_buf[i]);
        max_size = max(max_size, sizes[i]);
        i++;
        bptr = big_buf;
        *bptr++ = '\007'; /* send something to wake them up */
        *bptr++ = '\r'; /* add a \r in case of raw mode */
        *bptr++ = '\n';
        for (i = 0; i < N_LINES; i++) {
                /* copy the line into the big buffer */
                lptr = line_buf[i];
                while (*lptr != '\0')
                        *(bptr++) = *(lptr++);
                /* pad out the rest of the lines with blanks */
                for (j = sizes[i]; j < max_size + 2; j++)
                        *(bptr++) = ' ';
                *(bptr++) = '\r';       /* add a \r in case of raw mode */
                *(bptr++) = '\n';
        }
        *bptr = '\0';
        fprintf(tf, "%s", big_buf);
        fflush(tf);
}