/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*      Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
/*        All Rights Reserved   */
/*
 * Copyright (c) 2016 by Delphix. All rights reserved.
 */

/*
 * University Copyright- Copyright (c) 1982, 1986, 1988
 * The Regents of the University of California
 * All Rights Reserved
 *
 * University Acknowledgment- Portions of this document are derived from
 * software developed by the University of California, Berkeley, and its
 * contributors.
 */

#include "rcv.h"
#include <locale.h>

/*
 * mailx -- a modified version of a University of California at Berkeley
 *      mail program
 *
 * Rcv -- receive mail rationally.
 *
 * Termination processing.
 */

static void             writeback(int noremove);

#define PRIV(x)         setgid(myegid), (x), setgid(myrgid);

/*
 * Save all of the undetermined messages at the top of "mbox"
 * Save all untouched messages back in the system mailbox.
 * Remove the system mailbox, if none saved there.
 */

void
quit(
    int noremove        /* don't remove system mailbox, trunc it instead */
)
{
        int mcount, p, modify, autohold, anystat, holdbit, nohold, fd;
        FILE *ibuf, *obuf, *fbuf, *readstat;
        register struct message *mp;
        register int c;
        char *id;
        int appending;
        char *mbox = Getf("MBOX");

        /*
         * If we are read only, we can't do anything,
         * so just return quickly.
         */

        mcount = 0;
        if (readonly)
                return;
        /*
         * See if there any messages to save in mbox.  If no, we
         * can save copying mbox to /tmp and back.
         *
         * Check also to see if any files need to be preserved.
         * Delete all untouched messages to keep them out of mbox.
         * If all the messages are to be preserved, just exit with
         * a message.
         *
         * If the luser has sent mail to himself, refuse to do
         * anything with the mailbox, unless mail locking works.
         */

#ifndef CANLOCK
        if (selfsent) {
                printf(gettext("You have new mail.\n"));
                return;
        }
#endif

        /*
         * Adjust the message flags in each message.
         */

        anystat = 0;
        autohold = value("hold") != NOSTR;
        appending = value("append") != NOSTR;
        holdbit = autohold ? MPRESERVE : MBOX;
        nohold = MBOXED|MBOX|MSAVED|MDELETED|MPRESERVE;
        if (value("keepsave") != NOSTR)
                nohold &= ~MSAVED;
        for (mp = &message[0]; mp < &message[msgCount]; mp++) {
                if (mp->m_flag & MNEW) {
                        receipt(mp);
                        mp->m_flag &= ~MNEW;
                        mp->m_flag |= MSTATUS;
                }
                if (mp->m_flag & MSTATUS)
                        anystat++;
                if ((mp->m_flag & MTOUCH) == 0)
                        mp->m_flag |= MPRESERVE;
                if ((mp->m_flag & nohold) == 0)
                        mp->m_flag |= holdbit;
        }
        modify = 0;
        if (Tflag != NOSTR) {
                if ((readstat = fopen(Tflag, "w")) == NULL)
                        Tflag = NOSTR;
        }
        for (c = 0, p = 0, mp = &message[0]; mp < &message[msgCount]; mp++) {
                if (mp->m_flag & MBOX)
                        c++;
                if (mp->m_flag & MPRESERVE)
                        p++;
                if (mp->m_flag & MODIFY)
                        modify++;
                if (Tflag != NOSTR && (mp->m_flag & (MREAD|MDELETED)) != 0) {
                        id = hfield("message-id", mp, addone);
                        if (id != NOSTR)
                                fprintf(readstat, "%s\n", id);
                        else {
                                id = hfield("article-id", mp, addone);
                                if (id != NOSTR)
                                        fprintf(readstat, "%s\n", id);
                        }
                }
        }
        if (Tflag != NOSTR)
                fclose(readstat);
        if (p == msgCount && !modify && !anystat) {
                if (p == 1)
                        printf(gettext("Held 1 message in %s\n"), mailname);
                else
                        printf(gettext("Held %d messages in %s\n"), p,
                            mailname);
                return;
        }
        if (c == 0) {
                writeback(noremove);
                return;
        }

        /*
         * Create another temporary file and copy user's mbox file
         * therein.  If there is no mbox, copy nothing.
         * If they have specified "append" don't copy the mailbox,
         * just copy saveable entries at the end.
         */

        mcount = c;
        if (!appending) {
                if ((fd = open(tempQuit, O_RDWR|O_CREAT|O_EXCL, 0600)) < 0 ||
                (obuf = fdopen(fd, "w")) == NULL) {
                        perror(tempQuit);
                        return;
                }
                if ((ibuf = fopen(tempQuit, "r")) == NULL) {
                        perror(tempQuit);
                        removefile(tempQuit);
                        fclose(obuf);
                        return;
                }
                removefile(tempQuit);
                if ((fbuf = fopen(mbox, "r")) != NULL) {
                        while ((c = getc(fbuf)) != EOF)
                                putc(c, obuf);
                        fclose(fbuf);
                }
                fflush(obuf);
                if (fferror(obuf)) {
                        perror(tempQuit);
                        fclose(ibuf);
                        fclose(obuf);
                        return;
                }
                fclose(obuf);
                if ((fd = open(mbox, O_RDWR|O_CREAT|O_TRUNC, MBOXPERM)) < 0 ||
                    (obuf = fdopen(fd, "r+")) == NULL) {
                        perror(mbox);
                        fclose(ibuf);
                        return;
                }
                if (issysmbox)
                        touchlock();
        } else {        /* we are appending */
                if ((fd = open(mbox, O_RDWR|O_CREAT, MBOXPERM)) < 0 ||
                    (obuf = fdopen(fd, "a")) == NULL) {
                        perror(mbox);
                        return;
                }
        }
        for (mp = &message[0]; mp < &message[msgCount]; mp++)
                if (mp->m_flag & MBOX) {
                        if (msend(mp, obuf, (int)value("alwaysignore") ?
                            M_IGNORE|M_SAVING : M_SAVING, fputs) < 0) {
                                perror(mbox);
                                if (!appending)
                                        fclose(ibuf);
                                fclose(obuf);
                                return;
                        }
                        mp->m_flag &= ~MBOX;
                        mp->m_flag |= MBOXED;
                        if (issysmbox)
                                touchlock();
                }

        /*
         * Copy the user's old mbox contents back
         * to the end of the stuff we just saved.
         * If we are appending, this is unnecessary.
         */

        if (!appending) {
                rewind(ibuf);
                c = getc(ibuf);
                while (c != EOF) {
                        putc(c, obuf);
                        if (ferror(obuf))
                                break;
                        c = getc(ibuf);
                }
                fclose(ibuf);
                fflush(obuf);
        }
        trunc(obuf);
        if (fferror(obuf)) {
                perror(mbox);
                fclose(obuf);
                return;
        }
        fclose(obuf);
        if (mcount == 1)
                printf(gettext("Saved 1 message in %s\n"), mbox);
        else
                printf(gettext("Saved %d messages in %s\n"), mcount, mbox);

        /*
         * Now we are ready to copy back preserved files to
         * the system mailbox, if any were requested.
         */
        writeback(noremove);
}

/*
 * Preserve all the appropriate messages back in the system
 * mailbox, and print a nice message indicating how many were
 * saved.  Incorporate any new mail that we found.
 */
static void
writeback(int noremove)
{
        register struct message *mp;
        register int p, c;
        struct stat st;
        FILE *obuf = 0, *fbuf = 0, *rbuf = 0;
        void (*fhup)(int), (*fint)(int), (*fquit)(int);
        int fd = -1;

        fhup = sigset(SIGHUP, SIG_IGN);
        fint = sigset(SIGINT, SIG_IGN);
        fquit = sigset(SIGQUIT, SIG_IGN);

        if (issysmbox)
                lockmail();
        if ((fbuf = fopen(mailname, "r+")) == NULL) {
                perror(mailname);
                goto die;
        }
        if (!issysmbox)
                lock(fbuf, "r+", 1);
        fstat(fileno(fbuf), &st);
        if (st.st_size > mailsize) {
                printf(gettext("New mail has arrived.\n"));
                snprintf(tempResid, PATHSIZE, "%s/:saved/%s", maildir, myname);
                PRIV(rbuf = fopen(tempResid, "w+"));
                if (rbuf == NULL) {
                        snprintf(tempResid, PATHSIZE, "/tmp/Rq%-ld", mypid);
                        fd = open(tempResid,O_RDWR|O_CREAT|O_EXCL, 0600);
                        PRIV(rbuf = fdopen(fd, "w+"));
                        if (rbuf == NULL) {
                                snprintf(tempResid, PATHSIZE,
                                        "%s/:saved/%s", maildir,
                                    myname);
                                perror(tempResid);
                                fclose(fbuf);
                                goto die;
                        }
                }
#ifdef APPEND
                fseek(fbuf, mailsize, 0);
                while ((c = getc(fbuf)) != EOF)
                        putc(c, rbuf);
#else
                p = st.st_size - mailsize;
                while (p-- > 0) {
                        c = getc(fbuf);
                        if (c == EOF) {
                                perror(mailname);
                                fclose(fbuf);
                                goto die;
                        }
                        putc(c, rbuf);
                }
#endif
                fclose(fbuf);
                fseek(rbuf, 0L, 0);
                if (issysmbox)
                        touchlock();
        }

        if ((obuf = fopen(mailname, "r+")) == NULL) {
                perror(mailname);
                goto die;
        }
#ifndef APPEND
        if (rbuf != NULL)
                while ((c = getc(rbuf)) != EOF)
                        putc(c, obuf);
#endif
        p = 0;
        for (mp = &message[0]; mp < &message[msgCount]; mp++)
                if ((mp->m_flag&MPRESERVE)||(mp->m_flag&MTOUCH)==0) {
                        p++;
                        if (msend(mp, obuf, 0, fputs) < 0) {
                                perror(mailname);
                                goto die;
                        }
                        if (issysmbox)
                                touchlock();
                }
#ifdef APPEND
        if (rbuf != NULL)
                while ((c = getc(rbuf)) != EOF)
                        putc(c, obuf);
#endif
        fflush(obuf);
        trunc(obuf);
        if (fferror(obuf)) {
                perror(mailname);
                goto die;
        }
        alter(mailname);
        if (p) {
                if (p == 1)
                        printf(gettext("Held 1 message in %s\n"), mailname);
                else
                        printf(gettext("Held %d messages in %s\n"), p,
                            mailname);
        }

        if (!noremove && (fsize(obuf) == 0) && (value("keep") == NOSTR)) {
                if (stat(mailname, &st) >= 0)
                        PRIV(delempty(st.st_mode, mailname));
        }

die:
        if (rbuf) {
                fclose(rbuf);
                PRIV(removefile(tempResid));
        }
        if (obuf)
                fclose(obuf);
        if (issysmbox)
                unlockmail();
        sigset(SIGHUP, fhup);
        sigset(SIGINT, fint);
        sigset(SIGQUIT, fquit);
}

void
lockmail(void)
{
    PRIV(maillock(lockname,10));
}

void
unlockmail(void)
{
    PRIV(mailunlock());
}