root/bin/sh/mail.c
/*      $NetBSD: mail.c,v 1.18 2017/06/04 20:28:13 kre Exp $    */

/*-
 * Copyright (c) 1991, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Kenneth Almquist.
 *
 * 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/cdefs.h>
#ifndef lint
#if 0
static char sccsid[] = "@(#)mail.c      8.2 (Berkeley) 5/4/95";
#else
__RCSID("$NetBSD: mail.c,v 1.18 2017/06/04 20:28:13 kre Exp $");
#endif
#endif /* not lint */

/*
 * Routines to check for mail.  (Perhaps make part of main.c?)
 */
#include <sys/types.h>
#include <sys/stat.h>
#include <stdlib.h>
#include <string.h>

#include "shell.h"
#include "exec.h"       /* defines padvance() */
#include "var.h"
#include "output.h"
#include "memalloc.h"
#include "error.h"
#include "mail.h"


#define MAXMBOXES 10


STATIC int nmboxes;                     /* number of mailboxes */
STATIC off_t mailsize[MAXMBOXES];       /* sizes of mailboxes */



/*
 * Print appropriate message(s) if mail has arrived.  If the argument is
 * nozero, then the value of MAIL has changed, so we just update the
 * values.
 */

void
chkmail(int silent)
{
        int i;
        const char *mpath;
        char *p;
        char *q;
        struct stackmark smark;
        struct stat statb;

        if (silent)
                nmboxes = 10;
        if (nmboxes == 0)
                return;
        setstackmark(&smark);
        mpath = mpathset() ? mpathval() : mailval();
        for (i = 0 ; i < nmboxes ; i++) {
                p = padvance(&mpath, nullstr, 1);
                if (p == NULL)
                        break;
                stunalloc(p);
                if (*p == '\0')
                        continue;
                for (q = p ; *q ; q++)
                        ;
                if (q[-1] != '/')
                        abort();
                q[-1] = '\0';                   /* delete trailing '/' */
#ifdef notdef /* this is what the System V shell claims to do (it lies) */
                if (stat(p, &statb) < 0)
                        statb.st_mtime = 0;
                if (statb.st_mtime > mailtime[i] && ! silent) {
                        out2str(pathopt ? pathopt : "you have mail");
                        out2c('\n');
                }
                mailtime[i] = statb.st_mtime;
#else /* this is what it should do */
                if (stat(p, &statb) < 0)
                        statb.st_size = 0;
                if (statb.st_size > mailsize[i] && ! silent) {
                        const char *pp;

                        if ((pp = pathopt) != NULL) {
                                int len = 0;

                                while (*pp && *pp != ':')
                                        len++, pp++;
                                if (len == 0) {
                                        CHECKSTRSPACE(16, p);
                                        strcat(p, ": file changed");
                                } else {
                                        while (stackblocksize() <= len)
                                                growstackblock();
                                        p = stackblock();
                                        memcpy(p, pathopt, len);
                                        p[len] = '\0';
                                }
                                pp = p;
                        } else
                                pp = "you have mail";

                        out2str(pp);
                        out2c('\n');
                }
                mailsize[i] = statb.st_size;
#endif
        }
        nmboxes = i;
        popstackmark(&smark);
}