[mmh] / sbr / folder_addmsg.c

/*
 * folder_addmsg.c -- Link message into folder
 *
 * $Id$
 *
 * This code is Copyright (c) 2002, by the authors of nmh.  See the
 * COPYRIGHT file in the root directory of the nmh distribution for
 * complete copyright information.
 */

#include <h/mh.h>
#include <fcntl.h>
#include <errno.h>

/*
 * Link message into a folder.  Return the new number
 * of the message.  If an error occurs, return -1.
 */

int
folder_addmsg (struct msgs **mpp, char *msgfile, int selected,
               int unseen, int preserve)
{
    int infd, outfd, linkerr, first_time, msgnum;
    char *nmsg, newmsg[BUFSIZ];
    struct msgs *mp;
    struct stat st1, st2;

    first_time = 1;     /* this is first attempt */
    mp = *mpp;

    /*
     * We might need to make several attempts
     * in order to add the message to the folder.
     */
    for (;;) {
        /*
         * Get the message number we will attempt to add.
         */
        if (first_time) {
            /* should we preserve the numbering of the message? */
            if (preserve && (msgnum = m_atoi (msgfile)) > 0) {
                ;
            } else if (mp->nummsg == 0) {
                /* check if we are adding to empty folder */
                msgnum = 1;
            } else {
                /* else use highest message number + 1 */
                msgnum = mp->hghmsg + 1;
            }
            first_time = 0;
        } else {
            /* another attempt, so try next higher message number */
            msgnum++;
        }

        /*
         * See if we need more space.  If we need space at the
         * end, then we allocate space for an addition 100 messages.
         * If we need space at the beginning of the range, then just
         * extend message status range to cover this message number.
         */
        if (msgnum > mp->hghoff) {
            if ((mp = folder_realloc (mp, mp->lowoff, msgnum + 100)))
                *mpp = mp;
            else {
                advise (NULL, "unable to allocate folder storage");
                return -1;
            }
        } else if (msgnum < mp->lowoff) {
            if ((mp = folder_realloc (mp, msgnum, mp->hghoff)))
                *mpp = mp;
            else {
                advise (NULL, "unable to allocate folder storage");
                return -1;
            }
        }

        /*
         * If a message is already in that slot,
         * then loop to next available slot.
         */
        if (does_exist (mp, msgnum))
            continue;

        /* setup the bit flags for this message */
        clear_msg_flags (mp, msgnum);
        set_exists (mp, msgnum);

        /* should we set the SELECT_UNSEEN bit? */
        if (unseen) {
            set_unseen (mp, msgnum);
        }

        /* should we set the SELECTED bit? */
        if (selected) {
            set_selected (mp, msgnum);

            /* check if highest or lowest selected */
            if (mp->numsel == 0) {
                mp->lowsel = msgnum;
                mp->hghsel = msgnum;
            } else {
                if (msgnum < mp->lowsel)
                    mp->lowsel = msgnum;
                if (msgnum > mp->hghsel)
                    mp->hghsel = msgnum;
            }

            /* increment number selected */
            mp->numsel++;
        }

        /*
         * check if this is highest or lowest message
         */
        if (mp->nummsg == 0) {
            mp->lowmsg = msgnum;
            mp->hghmsg = msgnum;
        } else {
            if (msgnum < mp->lowmsg)
                mp->lowmsg = msgnum;
            if (msgnum > mp->hghmsg)
                mp->hghmsg = msgnum;
        }

        /* increment message count */
        mp->nummsg++;

        nmsg = m_name (msgnum);
        snprintf (newmsg, sizeof(newmsg), "%s/%s", mp->foldpath, nmsg);

        /*
         * Now try to link message into folder
         */
        if (link (msgfile, newmsg) != -1) {
            return msgnum;
        } else {
            linkerr = errno;

#ifdef EISREMOTE
            if (linkerr == EISREMOTE)
                linkerr = EXDEV;
#endif /* EISREMOTE */

            /*
             * Check if the file in our desired location is the same
             * as the source file.  If so, then just leave it alone
             * and return.  Otherwise, we will continue the main loop
             * and try again at another slot (hghmsg+1).
             */
            if (linkerr == EEXIST) {
                if (stat (msgfile, &st2) == 0 && stat (newmsg, &st1) == 0
                    && st2.st_ino == st1.st_ino) {
                    return msgnum;
                } else {
                    continue;
                }
            }

            /*
             * If link failed because we are trying to link
             * across devices, then check if there is a message
             * already in the desired location.  If so, then return
             * error, else just copy the message.
             */
            if (linkerr == EXDEV) {
                if (stat (newmsg, &st1) == 0) {
                    advise (NULL, "message %s:%s already exists", newmsg);
                    return -1;
                } else {
                    if ((infd = open (msgfile, O_RDONLY)) == -1) {
                        advise (msgfile, "unable to open message %s");
                        return -1;
                    }
                    fstat (infd, &st1);
                    if ((outfd = creat (newmsg, (int) st1.st_mode & 0777)) == -1) {
                        advise (newmsg, "unable to create");
                        close (infd);
                        return -1;
                    }
                    cpydata (infd, outfd, msgfile, newmsg);
                    close (infd);
                    close (outfd);
                    return msgnum;
                }
            }

            /*
             * Else, some other type of link error,
             * so just return error.
             */
            advise (newmsg, "error linking %s to", msgfile);
            return -1;
        }
    }
}