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/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8; fill-column: 160 -*- */
/*
 *  Copyright (C) 2000 Helix Code Inc.
 *
 *  Authors: Michael Zucchi <notzed@helixcode.com>
 *
 *  This program is free software; you can redistribute it and/or 
 *  modify it under the terms of the GNU General Public License as 
 *  published by the Free Software Foundation; either version 2 of the
 *  License, or (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
 *  USA
 */

#include "camel-mbox-summary.h"
#include <camel/camel-mime-message.h>

#include <sys/stat.h>
#include <sys/uio.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <stdlib.h>

#define io(x)
#define d(x) x

#define CAMEL_MBOX_SUMMARY_VERSION (0x1000)

struct _CamelMboxSummaryPrivate {
};

#define _PRIVATE(o) (((CamelMboxSummary *)(o))->priv)

static int summary_header_load (CamelFolderSummary *, FILE *);
static int summary_header_save (CamelFolderSummary *, FILE *);

static CamelMessageInfo * message_info_new (CamelFolderSummary *, struct _header_raw *);
static CamelMessageInfo * message_info_new_from_parser (CamelFolderSummary *, CamelMimeParser *);
static CamelMessageInfo * message_info_load (CamelFolderSummary *, FILE *);
static int        message_info_save (CamelFolderSummary *, FILE *, CamelMessageInfo *);
/*static void         message_info_free (CamelFolderSummary *, CamelMessageInfo *);*/

static void camel_mbox_summary_class_init (CamelMboxSummaryClass *klass);
static void camel_mbox_summary_init       (CamelMboxSummary *obj);
static void camel_mbox_summary_finalise   (CamelObject *obj);

static CamelFolderSummaryClass *camel_mbox_summary_parent;

CamelType
camel_mbox_summary_get_type(void)
{
    static CamelType type = CAMEL_INVALID_TYPE;
    
    if (type == CAMEL_INVALID_TYPE) {
        type = camel_type_register(camel_folder_summary_get_type(), "CamelMboxSummary",
                       sizeof (CamelMboxSummary),
                       sizeof (CamelMboxSummaryClass),
                       (CamelObjectClassInitFunc) camel_mbox_summary_class_init,
                       NULL,
                       (CamelObjectInitFunc) camel_mbox_summary_init,
                       (CamelObjectFinalizeFunc) camel_mbox_summary_finalise);
    }
    
    return type;
}

static void
camel_mbox_summary_class_init(CamelMboxSummaryClass *klass)
{
    CamelFolderSummaryClass *sklass = (CamelFolderSummaryClass *) klass;
    
    camel_mbox_summary_parent = CAMEL_FOLDER_SUMMARY_CLASS(camel_type_get_global_classfuncs(camel_folder_summary_get_type()));

    sklass->summary_header_load = summary_header_load;
    sklass->summary_header_save = summary_header_save;

    sklass->message_info_new  = message_info_new;
    sklass->message_info_new_from_parser = message_info_new_from_parser;
    sklass->message_info_load = message_info_load;
    sklass->message_info_save = message_info_save;
    /*sklass->message_info_free = message_info_free;*/
}

static void
camel_mbox_summary_init(CamelMboxSummary *obj)
{
    struct _CamelMboxSummaryPrivate *p;
    struct _CamelFolderSummary *s = (CamelFolderSummary *)obj;

    p = _PRIVATE(obj) = g_malloc0(sizeof(*p));

    /* subclasses need to set the right instance data sizes */
    s->message_info_size = sizeof(CamelMboxMessageInfo);
    s->content_info_size = sizeof(CamelMboxMessageContentInfo);

    /* and a unique file version */
    s->version += CAMEL_MBOX_SUMMARY_VERSION;
}

static void
camel_mbox_summary_finalise(CamelObject *obj)
{
    CamelMboxSummary *mbs = CAMEL_MBOX_SUMMARY(obj);

    g_free(mbs->folder_path);
}

/**
 * camel_mbox_summary_new:
 *
 * Create a new CamelMboxSummary object.
 * 
 * Return value: A new CamelMboxSummary widget.
 **/
CamelMboxSummary *
camel_mbox_summary_new(const char *filename, const char *mbox_name, ibex *index)
{
    CamelMboxSummary *new = CAMEL_MBOX_SUMMARY(camel_object_new(camel_mbox_summary_get_type()));
    
    if (new) {
        /* ?? */
        camel_folder_summary_set_build_content(CAMEL_FOLDER_SUMMARY(new), TRUE);
        camel_folder_summary_set_filename(CAMEL_FOLDER_SUMMARY(new), filename);
        new->folder_path = g_strdup(mbox_name);
        new->index = index;
    }
    return new;
}

static int
summary_header_load(CamelFolderSummary *s, FILE *in)
{
    CamelMboxSummary *mbs = CAMEL_MBOX_SUMMARY(s);

    if (((CamelFolderSummaryClass *)camel_mbox_summary_parent)->summary_header_load(s, in) == -1)
        return -1;

    return camel_folder_summary_decode_uint32(in, &mbs->folder_size);
}

static int
summary_header_save(CamelFolderSummary *s, FILE *out)
{
    CamelMboxSummary *mbs = CAMEL_MBOX_SUMMARY(s);

    if (((CamelFolderSummaryClass *)camel_mbox_summary_parent)->summary_header_save(s, out) == -1)
        return -1;

    return camel_folder_summary_encode_uint32(out, mbs->folder_size);
}

static int
header_evolution_decode(const char *in, guint32 *uid, guint32 *flags)
{
        char *header;
    
        if (in && (header = header_token_decode(in))) {
                if (strlen (header) == strlen ("00000000-0000")
                    && sscanf (header, "%08x-%04x", uid, flags) == 2) {
                        g_free(header);
                        return *uid;
                }
                g_free(header);
        }

        return -1;
}

static char *
header_evolution_encode(guint32 uid, guint32 flags)
{
    return g_strdup_printf("%08x-%04x", uid, flags & 0xffff);
}

static CamelMessageInfo *
message_info_new(CamelFolderSummary *s, struct _header_raw *h)
{
    CamelMessageInfo *mi;

    mi = ((CamelFolderSummaryClass *)camel_mbox_summary_parent)->message_info_new(s, h);
    if (mi) {
        const char *xev;
        guint32 uid, flags;
        CamelMboxMessageInfo *mbi = (CamelMboxMessageInfo *)mi;

        xev = header_raw_find(&h, "X-Evolution", NULL);
        if (xev && header_evolution_decode(xev, &uid, &flags) != -1) {
            g_free(mi->uid);
            mi->uid = g_strdup_printf("%u", uid);
            if (camel_folder_summary_uid(s, mi->uid)) {
                g_free(mi->uid);
                mi->uid = camel_folder_summary_next_uid_string(s);
            } else {
                /* so we dont get clashes later on */
                camel_folder_summary_set_uid(s, uid+1);
            }
            mi->flags = flags;
        } else {
            /* to indicate it has no xev header? */
            mi->flags |= CAMEL_MESSAGE_FOLDER_FLAGGED | CAMEL_MESSAGE_FOLDER_NOXEV;
            mi->uid = g_strdup_printf("%u", camel_folder_summary_next_uid(s));
        }
        mbi->frompos = -1;
    }
    
    return mi;
}

static CamelMessageInfo *
message_info_new_from_parser(CamelFolderSummary *s, CamelMimeParser *mp)
{
    CamelMessageInfo *mi;
    CamelMboxSummary *mbs = CAMEL_MBOX_SUMMARY(s);

    mi = ((CamelFolderSummaryClass *)camel_mbox_summary_parent)->message_info_new_from_parser(s, mp);
    if (mi) {
        CamelMboxMessageInfo *mbi = (CamelMboxMessageInfo *)mi;

        mbi->frompos = camel_mime_parser_tell_start_from(mp);

        /* do we want to index this message as we add it, as well? */
        if (mbs->index
            && (mbs->index_force
            || (mi->flags & CAMEL_MESSAGE_FOLDER_FLAGGED) != 0
            || !ibex_contains_name(mbs->index, mi->uid))) {
            camel_folder_summary_set_index(s, mbs->index);
        } else {
            camel_folder_summary_set_index(s, NULL);
        }
    }
    
    return mi;
}

static CamelMessageInfo *
message_info_load(CamelFolderSummary *s, FILE *in)
{
    CamelMessageInfo *mi;

    io(printf("loading mbox message info\n"));

    mi = ((CamelFolderSummaryClass *)camel_mbox_summary_parent)->message_info_load(s, in);
    if (mi) {
        guint32 position;
        CamelMboxMessageInfo *mbi = (CamelMboxMessageInfo *)mi;

        camel_folder_summary_decode_uint32(in, &position);
        mbi->frompos = position;
    }
    
    return mi;
}

static int
message_info_save(CamelFolderSummary *s, FILE *out, CamelMessageInfo *mi)
{
    CamelMboxMessageInfo *mbi = (CamelMboxMessageInfo *)mi;

    io(printf("saving mbox message info\n"));

    ((CamelFolderSummaryClass *)camel_mbox_summary_parent)->message_info_save(s, out, mi);

    return camel_folder_summary_encode_uint32(out, mbi->frompos);
}

static int
summary_rebuild(CamelMboxSummary *mbs, off_t offset)
{
    CamelFolderSummary *s = CAMEL_FOLDER_SUMMARY(mbs);
    CamelMimeParser *mp;
    int fd;
    int ok = 0;

    fd = open(mbs->folder_path, O_RDONLY);
    if (fd == -1) {
        printf("%s failed to open: %s", mbs->folder_path, strerror(errno));
        return -1;
    }
    
    mp = camel_mime_parser_new();
    camel_mime_parser_init_with_fd(mp, fd);
    camel_mime_parser_scan_from(mp, TRUE);
    camel_mime_parser_seek(mp, offset, SEEK_SET);

    if (offset > 0) {
        if (camel_mime_parser_step(mp, NULL, NULL) == HSCAN_FROM) {
            if (camel_mime_parser_tell_start_from(mp) != offset) {
                g_warning ("The next message didn't start where I expected\nbuilding summary from start");
                camel_mime_parser_drop_step(mp);
                offset = 0;
                camel_mime_parser_seek(mp, offset, SEEK_SET);
                camel_folder_summary_clear(CAMEL_FOLDER_SUMMARY(mbs));
            } else {
                camel_mime_parser_unstep(mp);
            }
        } else {
            camel_object_unref(CAMEL_OBJECT(mp));
            /* end of file - no content? */
            return -1;
        }
    }

    while (camel_mime_parser_step(mp, NULL, NULL) == HSCAN_FROM) {
        CamelMessageInfo *info;

        info = camel_folder_summary_add_from_parser(CAMEL_FOLDER_SUMMARY(mbs), mp);
        if (info == NULL) {
            printf ("Could not build info from file?\n");
            ok = -1;
            break;
        }

        g_assert(camel_mime_parser_step(mp, NULL, NULL) == HSCAN_FROM_END);
    }

    camel_object_unref(CAMEL_OBJECT (mp));
    
    /* update the file size/mtime in the summary */
    if (ok != -1) {
        struct stat st;

        if (stat(mbs->folder_path, &st) == 0) {
            mbs->folder_size = st.st_size;
            s->time = st.st_mtime;
        }
    }

    return ok;
}

int
camel_mbox_summary_update(CamelMboxSummary *mbs, off_t offset, CamelFolderChangeInfo *changeinfo)
{
    int ret, i, count;
    CamelFolderSummary *s = (CamelFolderSummary *)mbs;

    /* we use the diff function of the change_info to build the update list. */
    for (i = 0; i < camel_folder_summary_count(s); i++) {
        CamelMessageInfo *mi = camel_folder_summary_index(s, i);

        camel_folder_change_info_add_source(changeinfo, mi->uid);
    }

    /* do the actual work */
    mbs->index_force = FALSE;
    ret = summary_rebuild(mbs, offset);

    count = camel_folder_summary_count(s);
    for (i = 0; i < count; i++) {
        CamelMessageInfo *mi = camel_folder_summary_index(s, i);
        camel_folder_change_info_add_update(changeinfo, mi->uid);
    }
    camel_folder_change_info_build_diff(changeinfo);
    
#if 0
#warning "Saving full summary and index after every summarisation is slow ..."
    if (ret != -1) {
        if (camel_folder_summary_save((CamelFolderSummary *)mbs) == -1)
            g_warning("Could not save summary: %s", strerror(errno));
        if (mbs->index)
            ibex_save(mbs->index);
    }
#endif
    return ret;
}

int
camel_mbox_summary_load(CamelMboxSummary *mbs, int forceindex)
{
    CamelFolderSummary *s = CAMEL_FOLDER_SUMMARY(mbs);
    struct stat st;
    int ret = 0;
    off_t minstart;

    mbs->index_force = forceindex;

    /* is the summary out of date? */
    if (stat(mbs->folder_path, &st) == -1) {
        camel_folder_summary_clear(s);
        printf("Cannot summarise folder: '%s': %s\n", mbs->folder_path, strerror(errno));
        return -1;
    }

    if (forceindex || camel_folder_summary_load(s) == -1) {
        camel_folder_summary_clear(s);
        ret = summary_rebuild(mbs, 0);
    } else {
        minstart = st.st_size;
#if 0
        /* find out the first unindexed message ... */
        /* TODO: For this to work, it has to check that the message is
           indexable, and contains content ... maybe it cannot be done 
           properly? */
        for (i = 0; i < camel_folder_summary_count(s); i++) {
            CamelMessageInfo *mi = camel_folder_summary_index(s, i);

            if (mbs->index && !ibex_contains_name(mbs->index, mi->uid)) {
                minstart = ((CamelMboxMessageInfo *) mi)->frompos;
                printf("Found unindexed message: %s\n", mi->uid);
                break;
            }
        }
#endif
        /* is the summary uptodate? */
        if (st.st_size == mbs->folder_size && st.st_mtime == s->time) {
            if (minstart < st.st_size) {
                /* FIXME: Only clear the messages and reindex from this point forward */
                camel_folder_summary_clear(s);
                ret = summary_rebuild(mbs, 0);
            }
        } else {
            if (mbs->folder_size < st.st_size) {
                if (minstart < mbs->folder_size) {
                    /* FIXME: only make it rebuild as necessary */
                    camel_folder_summary_clear(s);
                    ret = summary_rebuild(mbs, 0);
                } else {
                    ret = summary_rebuild(mbs, mbs->folder_size);
                    /* If that fails, it might be because a message was changed
                     * rather than appended... so try again from the beginning.
                     */
                    if (ret == -1) {
                        camel_folder_summary_clear(s);
                        ret = summary_rebuild(mbs, 0);
                    }
                }
            } else {
                camel_folder_summary_clear(s);
                ret = summary_rebuild(mbs, 0);
            }
        }
    }

    if (ret != -1) {
        mbs->folder_size = st.st_size;
        s->time = st.st_mtime;
        if (camel_folder_summary_save(s) == -1)
            g_warning("Could not save summary: %s", strerror(errno));
        if (mbs->index)
            ibex_save(mbs->index);
    }

    return ret;
}

static int
header_write(int fd, struct _header_raw *header, char *xevline)
{
    struct iovec iv[4];
    int outlen = 0, len;

    iv[1].iov_base = ":";
    iv[1].iov_len = 1;
    iv[3].iov_base = "\n";
    iv[3].iov_len = 1;

    while (header) {
        if (strcasecmp(header->name, "X-Evolution")) {
            iv[0].iov_base = header->name;
            iv[0].iov_len = strlen(header->name);
            iv[2].iov_base = header->value;
            iv[2].iov_len = strlen(header->value);

            do {
                len = writev(fd, iv, 4);
            } while (len == -1 && errno == EINTR);

            if (len == -1)
                return -1;
            outlen += len;
        }
        header = header->next;
    }

    iv[0].iov_base = "X-Evolution: ";
    iv[0].iov_len = strlen(iv[0].iov_base);
    iv[1].iov_base = xevline;
    iv[1].iov_len = strlen(xevline);
    iv[2].iov_base = "\n\n";
    iv[2].iov_len = 2;

    do {
        len = writev(fd, iv, 3);
    } while (len == -1 && errno == EINTR);

    if (len == -1)
        return -1;

    outlen += 1;

    d(printf("Wrote %d bytes of headers\n", outlen));

    return outlen;
}

static int
copy_block(int fromfd, int tofd, off_t start, size_t bytes)
{
    char buffer[4096];
    int written = 0;

    d(printf("writing %d bytes ... ", bytes));

    if (lseek(fromfd, start, SEEK_SET) != start)
        return -1;

    while (bytes > 0) {
        int toread, towrite;

        toread = bytes;
        if (bytes > 4096)
            toread = 4096;
        else
            toread = bytes;
        do {
            towrite = read(fromfd, buffer, toread);
        } while (towrite == -1 && errno == EINTR);

        if (towrite == -1)
            return -1;

        /* check for 'end of file' */
        if (towrite == 0) {
            d(printf("end of file?\n"));
            break;
        }

        do {
            toread = write(tofd, buffer, towrite);
        } while (toread == -1 && errno == EINTR);

        if (toread == -1)
            return -1;

        written += toread;
        bytes -= toread;
    }

    d(printf("written %d bytes\n", written));

    return written;
}

static char *tz_months[] = {
    "Jan", "Feb", "Mar", "Apr", "May", "Jun",
    "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
};

static char *tz_days[] = {
    "Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"
};

/* tries to build a From line, based on message headers */
char *
camel_mbox_summary_build_from(struct _header_raw *header)
{
    GString *out = g_string_new("From ");
    char *ret;
    const char *tmp;
    time_t thetime;
    int offset;
    struct tm tm;

    tmp = header_raw_find(&header, "Sender", NULL);
    if (tmp == NULL)
        tmp = header_raw_find(&header, "From", NULL);
    if (tmp != NULL) {
        struct _header_address *addr = header_address_decode(tmp);

        tmp = NULL;
        if (addr) {
            if (addr->type == HEADER_ADDRESS_NAME) {
                g_string_append(out, addr->v.addr);
                tmp = "";
            }
            header_address_unref(addr);
        }
    }
    if (tmp == NULL) {
        g_string_append(out, "unknown@nodomain.now.au");
    }

    /* try use the received header to get the date */
    tmp = header_raw_find(&header, "Received", NULL);
    if (tmp) {
        tmp = strrchr(tmp, ';');
        if (tmp)
            tmp++;
    }

    /* if there isn't one, try the Date field */
    if (tmp == NULL)
        tmp = header_raw_find(&header, "Date", NULL);

    thetime = header_decode_date(tmp, &offset);

    thetime += ((offset / 100) * (60 * 60)) + (offset % 100) * 60;

    /* a pseudo, but still bogus attempt at thread safing the function */
    /*memcpy(&tm, gmtime(&thetime), sizeof(tm));*/
    gmtime_r(&thetime, &tm);

    g_string_sprintfa(out, " %s %s %2d %02d:%02d:%02d %4d\n",
              tz_days[tm.tm_wday],
              tz_months[tm.tm_mon], tm.tm_mday, tm.tm_hour, tm.tm_min, tm.tm_sec, tm.tm_year + 1900);

    ret = out->str;
    g_string_free(out, FALSE);
    return ret;
}

int
camel_mbox_summary_sync(CamelMboxSummary *mbs, gboolean expunge, CamelFolderChangeInfo *changeinfo, CamelException *ex)
{
    CamelMimeParser *mp = NULL;
    int i, count;
    CamelMboxMessageInfo *info;
    CamelFolderSummary *s = CAMEL_FOLDER_SUMMARY(mbs);
    int fd = -1, fdout = -1;
    off_t offset = 0;
    char *tmpname = NULL;
    char *buffer, *xevnew = NULL;
    const char *xev;
    int len;
    guint32 uid, flags;
    int quick = TRUE, work = FALSE;
    struct stat st;
    char *fromline;

    /* make sure we're in sync, after this point we at least have a complete list of id's */
    count = camel_folder_summary_count (s);
    if (count > 0) {
        CamelMessageInfo *mi = camel_folder_summary_index(s, count - 1);
        camel_mbox_summary_update(mbs, mi->content->endpos, changeinfo);
    } else {
        camel_mbox_summary_update(mbs, 0, changeinfo);
    }

    /* check if we have any work to do */
    d(printf("Performing sync, %d messages in inbox\n", count));
    for (i = 0; quick && i < count; i++) {
        info = (CamelMboxMessageInfo *)camel_folder_summary_index(s, i);
        if ((expunge && (info->info.flags & CAMEL_MESSAGE_DELETED)) ||
            (info->info.flags & CAMEL_MESSAGE_FOLDER_NOXEV))
            quick = FALSE;
        else
            work |= (info->info.flags & CAMEL_MESSAGE_FOLDER_FLAGGED) != 0;
    }

    d(printf("Options: %s %s %s\n", expunge ? "expunge" : "", quick ? "quick" : "", work ? "Work" : ""));

    if (quick && !work)
        return 0;

    fd = open(mbs->folder_path, O_RDWR);
    if (fd == -1) {
        camel_exception_setv(ex, CAMEL_EXCEPTION_SYSTEM,
                     _("Could not open summary %s"), mbs->folder_path);
        return -1;
    }

    mp = camel_mime_parser_new();
    camel_mime_parser_scan_from(mp, TRUE);
    camel_mime_parser_init_with_fd(mp, fd);

    if (!quick) {
        tmpname = alloca(strlen (mbs->folder_path) + 5);
        sprintf(tmpname, "%s.tmp", mbs->folder_path);
        d(printf("Writing tmp file to %s\n", tmpname));
    retry_out:
        fdout = open(tmpname, O_WRONLY|O_CREAT|O_EXCL, 0600);
        if (fdout == -1) {
            if (errno == EEXIST)
                if (unlink(tmpname) != -1)
                    goto retry_out;
            
            tmpname = NULL;
            camel_exception_setv(ex, CAMEL_EXCEPTION_SYSTEM,
                         _("Cannot open temporary mailbox: %s"), strerror(errno));
            goto error;
        }
    }

    for (i = 0; i < count; i++) {
        off_t frompos, bodypos, lastpos;
        /* This has to be an int, not an off_t, because that's
         * what camel_mime_parser_header returns... FIXME.
         */
        int xevoffset;

        info = (CamelMboxMessageInfo *)camel_folder_summary_index(s, i);

        g_assert(info);

        d(printf("Looking at message %s\n", info->info.uid));

        if (expunge && info->info.flags & CAMEL_MESSAGE_DELETED) {
            d(printf("Deleting %s\n", info->info.uid));

            g_assert(!quick);
            offset -= (info->info.content->endpos - info->frompos);
            if (mbs->index)
                ibex_unindex(mbs->index, info->info.uid);
            /* remove it from teh change list */
            camel_folder_change_info_remove_uid(changeinfo, info->info.uid);
            camel_folder_summary_remove(s, (CamelMessageInfo *)info);
            count--;
            i--;
            info = NULL;
        } else if (info->info.flags & (CAMEL_MESSAGE_FOLDER_NOXEV | CAMEL_MESSAGE_FOLDER_FLAGGED)) {
            int xevok = FALSE;

            d(printf("Updating header for %s flags = %08x\n", info->info.uid, info->info.flags));

            /* find the next message, header parts */
            camel_mime_parser_seek(mp, info->frompos, SEEK_SET);
            if (camel_mime_parser_step(mp, &buffer, &len) != HSCAN_FROM) {
                g_warning("camel_mime_parser_step failed (1)");
                goto error;
            }

            if (camel_mime_parser_tell_start_from (mp) != info->frompos) {
                g_warning("Summary/mbox mismatch, aborting sync");
                camel_exception_setv (ex, CAMEL_EXCEPTION_SYSTEM,
                              _("Summary mismatch, aborting sync"));
                goto error;
            }
            
            if (camel_mime_parser_step (mp, &buffer, &len) == HSCAN_FROM_END) {
                g_warning("camel_mime_parser_step failed (2)");
                goto error;
            }

            /* Check if the X-Evolution header is valid.  */

            xev = camel_mime_parser_header(mp, "X-Evolution", &xevoffset);
            if (xev && header_evolution_decode (xev, &uid, &flags) != -1)
                xevok = TRUE;

            xevnew = header_evolution_encode(strtoul (info->info.uid, NULL, 10), info->info.flags & 0xffff);
            if (quick) {
                if (!xevok) {
                    g_warning("The summary told me I had an X-Evolution header, but i dont!");
                    camel_exception_setv(ex, CAMEL_EXCEPTION_SYSTEM,
                                 _("Summary mismatch, X-Evolution header missing"));
                    goto error;
                }
                buffer = g_strdup_printf("X-Evolution: %s", xevnew);
                lastpos = lseek(fd, 0, SEEK_CUR);
                lseek(fd, xevoffset, SEEK_SET);
                do {
                    len = write(fd, buffer, strlen (buffer));
                } while (len == -1 && errno == EINTR);
                lseek(fd, lastpos, SEEK_SET);
                g_free(buffer);
                if (len == -1) {
                    goto error;
                }
            } else {
                frompos = lseek(fdout, 0, SEEK_CUR);
                fromline = camel_mbox_summary_build_from(camel_mime_parser_headers_raw (mp));
                write(fdout, fromline, strlen(fromline));
                g_free(fromline);
                if (header_write(fdout, camel_mime_parser_headers_raw(mp), xevnew) == -1) {
                    d(printf("Error writing to tmp mailbox\n"));
                    camel_exception_setv(ex, CAMEL_EXCEPTION_SYSTEM,
                                 _("Error writing to temp mailbox: %s"),
                                 strerror(errno));
                    goto error;
                }
                bodypos = lseek(fdout, 0, SEEK_CUR);
                d(printf("pos = %d, endpos = %d, bodypos = %d\n",
                     (int) info->info.content->pos,
                     (int) info->info.content->endpos,
                     (int) info->info.content->bodypos));
                if (copy_block(fd, fdout, info->info.content->bodypos,
                           info->info.content->endpos - info->info.content->bodypos) == -1) {
                    g_warning("Cannot copy data to output fd");
                    camel_exception_setv(ex, CAMEL_EXCEPTION_SYSTEM,
                                 _("Cannot copy data to output file: %s"),
                                 strerror (errno));
                    goto error;
                }
                info->frompos = frompos;
                offset = bodypos - info->info.content->bodypos;
            }
            info->info.flags &= 0xffff;
            g_free(xevnew);
            xevnew = NULL;
            camel_mime_parser_drop_step(mp);
            camel_mime_parser_drop_step(mp);
        } else {
            if (!quick) {
                if (copy_block(fd, fdout, info->frompos,
                           info->info.content->endpos - info->frompos) == -1) {
                    g_warning("Cannot copy data to output fd");
                    camel_exception_setv(ex, CAMEL_EXCEPTION_SYSTEM,
                                 _("Cannot copy data to output file: %s"),
                                 strerror(errno));
                    goto error;
                }
                /* update from pos here? */
                info->frompos += offset;
            } else {
                d(printf("Nothing to do for this message\n"));
            }
        }
        if (!quick && info != NULL && offset != 0) {
            d(printf("offsetting content: %d\n", (int)offset));
            camel_folder_summary_offset_content(info->info.content, offset);
            d(printf("pos = %d, endpos = %d, bodypos = %d\n",
                 (int) info->info.content->pos,
                 (int) info->info.content->endpos,
                 (int) info->info.content->bodypos));
        }
    }

    d(printf("Closing folders\n"));

    if (close(fd) == -1) {
        g_warning("Cannot close source folder: %s", strerror(errno));
        camel_exception_setv(ex, CAMEL_EXCEPTION_SYSTEM,
                     _("Could not close source folder %s: %s"),
                     mbs->folder_path, strerror(errno));
        goto error;
    }

    if (!quick) {
        if (close(fdout) == -1) {
            g_warning("Cannot close tmp folder: %s", strerror(errno));
            camel_exception_setv(ex, CAMEL_EXCEPTION_SYSTEM,
                         _("Could not close temp folder: %s"),
                         strerror(errno));
            goto error;
        }

        if (rename(tmpname, mbs->folder_path) == -1) {
            g_warning("Cannot rename folder: %s", strerror(errno));
            camel_exception_setv(ex, CAMEL_EXCEPTION_SYSTEM,
                         _("Could not rename folder: %s"),
                         strerror(errno));
            goto error;
        }
        tmpname = NULL;

        if (mbs->index)
            ibex_save(mbs->index);
    }

    if (stat(mbs->folder_path, &st) == -1) {
        camel_exception_setv(ex, CAMEL_EXCEPTION_SYSTEM,
                     _("Unknown error: %s"),
                     strerror(errno));
        goto error;
    }

    camel_folder_summary_touch(s);
    s->time = st.st_mtime;
    mbs->folder_size = st.st_size;
    camel_folder_summary_save(s);

    camel_object_unref(CAMEL_OBJECT(mp));
    
    return 0;
 error:
    if (fd != -1)
        close(fd);
    
    if (fdout != -1)
        close(fdout);
    
    g_free(xevnew);
    
    if (tmpname)
        unlink(tmpname);
    if (mp)
        camel_object_unref(CAMEL_OBJECT(mp));

    return -1;
}