index/mbox/mbox-mail.c

	mbox-mail.c revision 6fcc89d6c081c4411660e68a29dc41e74e29f33c
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi/* Copyright (c) 2003-2008 Dovecot authors, see the included COPYING file */
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi#include "lib.h"
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi#include "ioloop.h"
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi#include "istream.h"
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi#include "index-mail.h"
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi#include "mbox-storage.h"
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi#include "mbox-file.h"
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi#include "mbox-lock.h"
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi#include "mbox-sync-private.h"
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi#include "istream-raw-mbox.h"
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi#include "istream-header-filter.h"
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi#include <fcntl.h>
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi#include <unistd.h>
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi#include <sys/stat.h>
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomistatic void mbox_prepare_resync(struct index_mail *mail)
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi{
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi    struct mbox_transaction_context *t =
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi        (struct mbox_transaction_context *)mail->trans;
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi    struct mbox_mailbox *mbox = (struct mbox_mailbox *)mail->ibox;
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi    if (mbox->mbox_lock_type == F_RDLCK) {
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi        if (mbox->mbox_lock_id == t->mbox_lock_id)
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi            t->mbox_lock_id = 0;
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi        (void)mbox_unlock(mbox, mbox->mbox_lock_id);
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi        mbox->mbox_lock_id = 0;
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi        i_assert(mbox->mbox_lock_type == F_UNLCK);
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi    }
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi}
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomistatic int mbox_mail_seek(struct index_mail *mail)
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi{
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi    struct mbox_transaction_context *t =
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi        (struct mbox_transaction_context *)mail->trans;
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi    struct mbox_mailbox *mbox = (struct mbox_mailbox *)mail->ibox;
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi    enum mbox_sync_flags sync_flags = 0;
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi    int ret, try;
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi    bool deleted;
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi    if (mail->mail.mail.expunged || mbox->syncing)
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi        return -1;
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi    for (try = 0; try < 2; try++) {
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi        if (mbox->mbox_lock_type == F_UNLCK) {
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi            sync_flags |= MBOX_SYNC_LOCK_READING;
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi            if (mbox_sync(mbox, sync_flags) < 0)
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi                return -1;
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi            /* refresh index file after mbox has been locked to
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi               make sure we get only up-to-date mbox offsets. */
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi            if (mail_index_refresh(mbox->ibox.index) < 0) {
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi                mail_storage_set_index_error(&mbox->ibox);
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi                return -1;
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi            }
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi            i_assert(mbox->mbox_lock_type != F_UNLCK);
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi            t->mbox_lock_id = mbox->mbox_lock_id;
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi        } else if ((sync_flags & MBOX_SYNC_FORCE_SYNC) != 0) {
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi            /* dirty offsets are broken and mbox is write-locked.
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi               sync it to update offsets. */
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi            if (mbox_sync(mbox, sync_flags) < 0)
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi                return -1;
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi        }
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi
4c78d9e646c4a1158d7167806937c02d86cdfc25Aki Tuomi        if (mbox_file_open_stream(mbox) < 0)
            return -1;

        ret = mbox_file_seek(mbox, mail->trans->trans_view,
                     mail->mail.mail.seq, &deleted);
        if (ret > 0) {
            /* success */
            break;
        }
        if (ret < 0) {
            if (deleted)
                mail_set_expunged(&mail->mail.mail);
            return -1;
        }

        /* we'll need to re-sync it completely */
        mbox_prepare_resync(mail);
        sync_flags |= MBOX_SYNC_UNDIRTY | MBOX_SYNC_FORCE_SYNC;
    }
    if (ret == 0) {
        mail_storage_set_critical(&mbox->storage->storage,
            "Losing sync for mail uid=%u in mbox file %s",
            mail->mail.mail.uid, mbox->path);
    }
    return 0;
}

static int mbox_mail_get_received_date(struct mail *_mail, time_t *date_r)
{
    struct index_mail *mail = (struct index_mail *)_mail;
    struct index_mail_data *data = &mail->data;
    struct mbox_mailbox *mbox = (struct mbox_mailbox *)mail->ibox;

    if (index_mail_get_received_date(_mail, date_r) == 0)
        return 0;

    if (mbox_mail_seek(mail) < 0)
        return -1;
    data->received_date =
        istream_raw_mbox_get_received_time(mbox->mbox_stream);
    if (data->received_date == (time_t)-1) {
        /* it's broken and conflicts with our "not found"
           return value. change it. */
        data->received_date = 0;
    }

    *date_r = data->received_date;
    return 0;
}

static int mbox_mail_get_save_date(struct mail *_mail, time_t *date_r)
{
    struct index_mail *mail = (struct index_mail *)_mail;
    struct index_mail_data *data = &mail->data;

    if (index_mail_get_save_date(_mail, date_r) == 0)
        return 0;

    /* no way to know this. save the current time into cache and use
       that from now on. this works only as long as the index files
       are permanent */
    data->save_date = ioloop_time;
    *date_r = data->save_date;
    return 0;
}

static int
mbox_mail_get_special(struct mail *_mail, enum mail_fetch_field field,
              const char **value_r)
{
#define EMPTY_MD5_SUM "00000000000000000000000000000000"
    struct index_mail *mail = (struct index_mail *)_mail;
    struct mbox_mailbox *mbox = (struct mbox_mailbox *)mail->ibox;

    switch (field) {
    case MAIL_FETCH_FROM_ENVELOPE:
        if (mbox_mail_seek(mail) < 0)
            return -1;

        *value_r = istream_raw_mbox_get_sender(mbox->mbox_stream);
        return 0;
    case MAIL_FETCH_HEADER_MD5:
        if (index_mail_get_special(_mail, field, value_r) < 0)
            return -1;
        if (**value_r != '\0' && strcmp(*value_r, EMPTY_MD5_SUM) != 0)
            return 0;

        /* i guess in theory the EMPTY_MD5_SUM is valid and can happen,
           but it's almost guaranteed that it means the MD5 sum is
           missing. recalculate it. */
        mbox->mbox_save_md5 = TRUE;
                mbox_prepare_resync(mail);
        if (mbox_sync(mbox, MBOX_SYNC_FORCE_SYNC) < 0)
            return -1;
        break;
    default:
        break;
    }

    return index_mail_get_special(_mail, field, value_r);
}

static int mbox_mail_get_physical_size(struct mail *_mail, uoff_t *size_r)
{
    struct index_mail *mail = (struct index_mail *)_mail;
    struct index_mail_data *data = &mail->data;
    struct mbox_mailbox *mbox = (struct mbox_mailbox *)mail->ibox;
    const struct mail_index_header *hdr;
    struct istream *input;
    struct message_size hdr_size;
    uoff_t old_offset, body_offset, body_size, next_offset;

    if (index_mail_get_physical_size(_mail, size_r) == 0)
        return 0;

    /* we want to return the header size as seen by mail_get_stream(). */
    old_offset = data->stream == NULL ? 0 : data->stream->v_offset;
    if (mail_get_stream(_mail, &hdr_size, NULL, &input) < 0)
        return -1;

    /* our header size varies, so don't do any caching */
    body_offset = istream_raw_mbox_get_body_offset(mbox->mbox_stream);
    if (body_offset == (uoff_t)-1) {
        mail_storage_set_critical(_mail->box->storage,
                      "Couldn't get mbox size");
        return -1;
    }

    /* use the next message's offset to avoid reading through the entire
       message body to find out its size */
    hdr = mail_index_get_header(mail->trans->trans_view);
    if (_mail->seq >= hdr->messages_count) {
        if (_mail->seq == hdr->messages_count) {
            /* last message, use the synced mbox size */
            int trailer_size;

            trailer_size = (mbox->storage->storage.flags &
                    MAIL_STORAGE_FLAG_SAVE_CRLF) != 0 ?
                2 : 1;
            body_size = hdr->sync_size - body_offset - trailer_size;
        } else {
            /* we're appending a new message */
            body_size = (uoff_t)-1;
        }
    } else if (mbox_file_lookup_offset(mbox, mail->trans->trans_view,
                       _mail->seq + 1, &next_offset) > 0) {
        body_size = next_offset - body_offset;
    } else {
        body_size = (uoff_t)-1;
    }

    /* verify that the calculated body size is correct */
    body_size = istream_raw_mbox_get_body_size(mbox->mbox_stream,
                           body_size);

    data->physical_size = hdr_size.physical_size + body_size;
    *size_r = data->physical_size;

    i_stream_seek(input, old_offset);
    return 0;
}

static int mbox_mail_get_stream(struct mail *_mail,
                struct message_size *hdr_size,
                struct message_size *body_size,
                struct istream **stream_r)
{
    struct index_mail *mail = (struct index_mail *)_mail;
    struct index_mail_data *data = &mail->data;
    struct mbox_mailbox *mbox = (struct mbox_mailbox *)mail->ibox;
    struct istream *raw_stream;
    uoff_t offset;

    if (data->stream == NULL) {
        if (mbox_mail_seek(mail) < 0)
            return -1;

        raw_stream = mbox->mbox_stream;
        offset = istream_raw_mbox_get_header_offset(raw_stream);
        i_stream_seek(raw_stream, offset);
        raw_stream = i_stream_create_limit(raw_stream, (uoff_t)-1);
        data->stream =
            i_stream_create_header_filter(raw_stream,
                HEADER_FILTER_EXCLUDE | HEADER_FILTER_NO_CR,
                mbox_hide_headers, mbox_hide_headers_count,
                null_header_filter_callback, NULL);
        i_stream_unref(&raw_stream);
    }

    return index_mail_init_stream(mail, hdr_size, body_size, stream_r);
}

static void mbox_mail_set_seq(struct mail *_mail, uint32_t seq)
{
    struct index_mail *mail = (struct index_mail *)_mail;

    index_mail_set_seq(_mail, seq);
    mail->data.dont_cache_fetch_fields |= MAIL_FETCH_PHYSICAL_SIZE;
}

static bool mbox_mail_set_uid(struct mail *_mail, uint32_t uid)
{
    struct index_mail *mail = (struct index_mail *)_mail;
    bool ret;

    ret = index_mail_set_uid(_mail, uid);
    mail->data.dont_cache_fetch_fields |= MAIL_FETCH_PHYSICAL_SIZE;
    return ret;
}

struct mail_vfuncs mbox_mail_vfuncs = {
    index_mail_close,
    index_mail_free,
    mbox_mail_set_seq,
    mbox_mail_set_uid,

    index_mail_get_flags,
    index_mail_get_keywords,
    index_mail_get_keyword_indexes,
    index_mail_get_parts,
    index_mail_get_date,
    mbox_mail_get_received_date,
    mbox_mail_get_save_date,
    index_mail_get_virtual_size,
    mbox_mail_get_physical_size,
    index_mail_get_first_header,
    index_mail_get_headers,
    index_mail_get_header_stream,
    mbox_mail_get_stream,
    mbox_mail_get_special,
    index_mail_update_flags,
    index_mail_update_keywords,
    index_mail_expunge,
    index_mail_set_cache_corrupted
};