plugins/virtual/virtual-mail.c

	virtual-mail.c revision d979c1179d55ad86e40f869e48ef3e4db9c817b5
c25356d5978632df6203437e1953bcb29e0c736fTimo Sirainen/* Copyright (c) 2008-2014 Dovecot authors, see the included COPYING file */
c25356d5978632df6203437e1953bcb29e0c736fTimo Sirainen
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen#include "lib.h"
2423da95ee20fd4b3c260c1389cf2952d25f099cTimo Sirainen#include "array.h"
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen#include "index-mail.h"
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen#include "virtual-storage.h"
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen#include "virtual-transaction.h"
ef50336eefcb9ba99f73c6af37420eaf8857a39bTimo Sirainen
ef50336eefcb9ba99f73c6af37420eaf8857a39bTimo Sirainenstruct virtual_mail {
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen    struct index_mail imail;
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen    enum mail_fetch_field wanted_fields;
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen    struct mailbox_header_lookup_ctx *wanted_headers;
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen
533bfba437e4120aa29dd45bca2aa87e30ee28a2Timo Sirainen    /* currently active mail */
533bfba437e4120aa29dd45bca2aa87e30ee28a2Timo Sirainen    struct mail *cur_backend_mail;
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen    struct virtual_mail_index_record cur_vrec;
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen    /* all allocated mails */
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen    ARRAY(struct mail *) backend_mails;
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen    /* mail is lost if backend_mail doesn't point to correct mail */
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen    unsigned int cur_lost:1;
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen};
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainenstruct mail *
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainenvirtual_mail_alloc(struct mailbox_transaction_context *t,
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen           enum mail_fetch_field wanted_fields,
533bfba437e4120aa29dd45bca2aa87e30ee28a2Timo Sirainen           struct mailbox_header_lookup_ctx *wanted_headers)
533bfba437e4120aa29dd45bca2aa87e30ee28a2Timo Sirainen{
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen    struct virtual_mailbox *mbox = (struct virtual_mailbox *)t->box;
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen    struct virtual_mail *vmail;
d92f33f13830ba23d814342bf3ea8db721a15bb1Timo Sirainen    pool_t pool;
d92f33f13830ba23d814342bf3ea8db721a15bb1Timo Sirainen
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen    pool = pool_alloconly_create("vmail", 1024);
61e84692827b6a64912343f515c984853021483aTimo Sirainen    vmail = p_new(pool, struct virtual_mail, 1);
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen    vmail->imail.mail.pool = pool;
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen    vmail->imail.mail.data_pool =
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen        pool_alloconly_create("virtual index_mail", 512);
b039dabf4c53f72454e795930e7643b6e0e625f9Timo Sirainen    vmail->imail.mail.v = virtual_mail_vfuncs;
b039dabf4c53f72454e795930e7643b6e0e625f9Timo Sirainen    vmail->imail.mail.mail.box = t->box;
b039dabf4c53f72454e795930e7643b6e0e625f9Timo Sirainen    vmail->imail.mail.mail.transaction = t;
b039dabf4c53f72454e795930e7643b6e0e625f9Timo Sirainen    array_create(&vmail->imail.mail.module_contexts, pool,
b039dabf4c53f72454e795930e7643b6e0e625f9Timo Sirainen             sizeof(void *), 5);
b039dabf4c53f72454e795930e7643b6e0e625f9Timo Sirainen
b039dabf4c53f72454e795930e7643b6e0e625f9Timo Sirainen    vmail->imail.ibox = INDEX_STORAGE_CONTEXT(t->box);
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen    vmail->wanted_fields = wanted_fields;
b039dabf4c53f72454e795930e7643b6e0e625f9Timo Sirainen    if (wanted_headers != NULL) {
b039dabf4c53f72454e795930e7643b6e0e625f9Timo Sirainen        vmail->wanted_headers = wanted_headers;
b039dabf4c53f72454e795930e7643b6e0e625f9Timo Sirainen        mailbox_header_lookup_ref(wanted_headers);
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen    }
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen
8e371a3ce32bd64288786855b8ce0cb63f19f7d1Timo Sirainen    i_array_init(&vmail->backend_mails, array_count(&mbox->backend_boxes));
8e371a3ce32bd64288786855b8ce0cb63f19f7d1Timo Sirainen    return &vmail->imail.mail.mail;
8e371a3ce32bd64288786855b8ce0cb63f19f7d1Timo Sirainen}
8e371a3ce32bd64288786855b8ce0cb63f19f7d1Timo Sirainen
8e371a3ce32bd64288786855b8ce0cb63f19f7d1Timo Sirainenstatic void virtual_mail_free(struct mail *mail)
8e371a3ce32bd64288786855b8ce0cb63f19f7d1Timo Sirainen{
8e371a3ce32bd64288786855b8ce0cb63f19f7d1Timo Sirainen    struct virtual_mail *vmail = (struct virtual_mail *)mail;
8e371a3ce32bd64288786855b8ce0cb63f19f7d1Timo Sirainen    struct mail **mails;
8e371a3ce32bd64288786855b8ce0cb63f19f7d1Timo Sirainen    unsigned int i, count;
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen    mails = array_get_modifiable(&vmail->backend_mails, &count);
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen    for (i = 0; i < count; i++)
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen        mail_free(&mails[i]);
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen    array_free(&vmail->backend_mails);
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen    if (vmail->wanted_headers != NULL)
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen        mailbox_header_lookup_unref(&vmail->wanted_headers);
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen
c58906589cafc32df4c04ffbef933baadd3f2276Timo Sirainen    pool_unref(&vmail->imail.mail.data_pool);
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen    pool_unref(&vmail->imail.mail.pool);
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen}
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen
5694eeb99b69dea8033ca77ad69743c6b4871370Timo Sirainenstatic struct mail *
5694eeb99b69dea8033ca77ad69743c6b4871370Timo Sirainenbackend_mail_find(struct virtual_mail *vmail, struct mailbox *box)
5694eeb99b69dea8033ca77ad69743c6b4871370Timo Sirainen{
5694eeb99b69dea8033ca77ad69743c6b4871370Timo Sirainen    struct mail *const *mails;
ff7056842f14fd3b30a2d327dfab165b9d15dd30Timo Sirainen    unsigned int i, count;
ff7056842f14fd3b30a2d327dfab165b9d15dd30Timo Sirainen
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen    mails = array_get(&vmail->backend_mails, &count);
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen    for (i = 0; i < count; i++) {
8e371a3ce32bd64288786855b8ce0cb63f19f7d1Timo Sirainen        if (mails[i]->box == box)
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen            return mails[i];
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen    }
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen    return NULL;
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen}
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainenstatic int backend_mail_get(struct virtual_mail *vmail,
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen                struct mail **backend_mail_r)
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen{
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen    struct mail *mail = &vmail->imail.mail.mail;
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen    struct virtual_mailbox *mbox = (struct virtual_mailbox *)mail->box;
8e371a3ce32bd64288786855b8ce0cb63f19f7d1Timo Sirainen    struct virtual_backend_box *bbox;
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen    *backend_mail_r = NULL;
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen
adb6413686e52e00dded4932babcc08ff041876bTimo Sirainen    if (vmail->cur_backend_mail != NULL) {
adb6413686e52e00dded4932babcc08ff041876bTimo Sirainen        if (vmail->cur_lost) {
adb6413686e52e00dded4932babcc08ff041876bTimo Sirainen            mail_set_expunged(&vmail->imail.mail.mail);
adb6413686e52e00dded4932babcc08ff041876bTimo Sirainen            return -1;
b039dabf4c53f72454e795930e7643b6e0e625f9Timo Sirainen        }
b039dabf4c53f72454e795930e7643b6e0e625f9Timo Sirainen        *backend_mail_r = vmail->cur_backend_mail;
b039dabf4c53f72454e795930e7643b6e0e625f9Timo Sirainen        return 0;
ef50336eefcb9ba99f73c6af37420eaf8857a39bTimo Sirainen    }
ef50336eefcb9ba99f73c6af37420eaf8857a39bTimo Sirainen
ef50336eefcb9ba99f73c6af37420eaf8857a39bTimo Sirainen    bbox = virtual_backend_box_lookup(mbox, vmail->cur_vrec.mailbox_id);
ef50336eefcb9ba99f73c6af37420eaf8857a39bTimo Sirainen    vmail->cur_backend_mail = backend_mail_find(vmail, bbox->box);
ef50336eefcb9ba99f73c6af37420eaf8857a39bTimo Sirainen    if (vmail->cur_backend_mail == NULL) {
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen        if (!bbox->box->opened &&
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen            virtual_backend_box_open(mbox, bbox) < 0) {
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen            virtual_box_copy_error(mail->box, bbox->box);
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen            return -1;
ff7056842f14fd3b30a2d327dfab165b9d15dd30Timo Sirainen        }
ff7056842f14fd3b30a2d327dfab165b9d15dd30Timo Sirainen        (void)virtual_mail_set_backend_mail(mail, bbox);
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen    }
43d32cbe60fdaef2699d99f1ca259053e9350411Timo Sirainen    virtual_backend_box_accessed(mbox, bbox);
5fb3bff645380804c9db2510940c41db6b8fdb01Timo Sirainen    vmail->cur_lost = !mail_set_uid(vmail->cur_backend_mail,
ff7056842f14fd3b30a2d327dfab165b9d15dd30Timo Sirainen                    vmail->cur_vrec.real_uid);
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen    mail->expunged = vmail->cur_lost || vmail->cur_backend_mail->expunged;
a27e065f1a1f91c7fbdf7c2ea1c387441af0cbb3Timo Sirainen    if (vmail->cur_lost) {
        mail_set_expunged(&vmail->imail.mail.mail);
        return -1;
    }
    *backend_mail_r = vmail->cur_backend_mail;
    return 0;
}

struct mail *
virtual_mail_set_backend_mail(struct mail *mail,
                  struct virtual_backend_box *bbox)
{
    struct virtual_mail *vmail = (struct virtual_mail *)mail;
    struct mail_private *backend_pmail;
    struct mailbox_transaction_context *backend_trans;
    struct mailbox_header_lookup_ctx *backend_headers;

    i_assert(bbox->box->opened);

    backend_trans = virtual_transaction_get(mail->transaction, bbox->box);

    backend_headers = vmail->wanted_headers == NULL ? NULL :
        mailbox_header_lookup_init(bbox->box,
                       vmail->wanted_headers->name);
    vmail->cur_backend_mail =
        mail_alloc(backend_trans, vmail->wanted_fields, backend_headers);
    if (backend_headers != NULL)
        mailbox_header_lookup_unref(&backend_headers);

    backend_pmail = (struct mail_private *)vmail->cur_backend_mail;
    backend_pmail->vmail = mail;
    array_append(&vmail->backend_mails, &vmail->cur_backend_mail, 1);
    return vmail->cur_backend_mail;
}

static void virtual_mail_set_seq(struct mail *mail, uint32_t seq, bool saving)
{
    struct virtual_mail *vmail = (struct virtual_mail *)mail;
    struct virtual_mailbox *mbox = (struct virtual_mailbox *)mail->box;
    const void *data;

    i_assert(!saving);

    mail_index_lookup_ext(mail->transaction->view, seq,
                  mbox->virtual_ext_id, &data, NULL);
    memcpy(&vmail->cur_vrec, data, sizeof(vmail->cur_vrec));

    memset(&vmail->imail.data, 0, sizeof(vmail->imail.data));
    p_clear(vmail->imail.mail.data_pool);

    vmail->imail.data.seq = seq;
    mail->seq = seq;
    mail_index_lookup_uid(mail->transaction->view, seq, &mail->uid);

    vmail->cur_backend_mail = NULL;
}

static bool virtual_mail_set_uid(struct mail *mail, uint32_t uid)
{
    uint32_t seq;

    if (!mail_index_lookup_seq(mail->transaction->view, uid, &seq))
        return FALSE;

    virtual_mail_set_seq(mail, seq, FALSE);
    return TRUE;
}

static void virtual_mail_set_uid_cache_updates(struct mail *mail, bool set)
{
    struct virtual_mail *vmail = (struct virtual_mail *)mail;
    struct mail *backend_mail;
    struct mail_private *p;

    if (backend_mail_get(vmail, &backend_mail) < 0)
        return;
    p = (struct mail_private *)backend_mail;
    p->v.set_uid_cache_updates(backend_mail, set);
}

static bool virtual_mail_prefetch(struct mail *mail)
{
    struct virtual_mail *vmail = (struct virtual_mail *)mail;
    struct mail *backend_mail;
    struct mail_private *p;

    if (backend_mail_get(vmail, &backend_mail) < 0)
        return TRUE;
    p = (struct mail_private *)backend_mail;
    return p->v.prefetch(backend_mail);
}

static void virtual_mail_precache(struct mail *mail)
{
    struct virtual_mail *vmail = (struct virtual_mail *)mail;
    struct mail *backend_mail;
    struct mail_private *p;

    if (backend_mail_get(vmail, &backend_mail) < 0)
        return;
    p = (struct mail_private *)backend_mail;
    p->v.precache(backend_mail);
}

static void
virtual_mail_add_temp_wanted_fields(struct mail *mail,
                    enum mail_fetch_field fields,
                    struct mailbox_header_lookup_ctx *headers)
{
    struct virtual_mail *vmail = (struct virtual_mail *)mail;
    struct mail *backend_mail;
    struct mail_private *p;

    if (backend_mail_get(vmail, &backend_mail) < 0)
        return;
    p = (struct mail_private *)backend_mail;
    p->v.add_temp_wanted_fields(backend_mail, fields, headers);
}

static int
virtual_mail_get_parts(struct mail *mail, struct message_part **parts_r)
{
    struct virtual_mail *vmail = (struct virtual_mail *)mail;
    struct mail *backend_mail;

    if (backend_mail_get(vmail, &backend_mail) < 0)
        return -1;
    if (mail_get_parts(backend_mail, parts_r) < 0) {
        virtual_box_copy_error(mail->box, backend_mail->box);
        return -1;
    }
    return 0;
}

static int
virtual_mail_get_date(struct mail *mail, time_t *date_r, int *timezone_r)
{
    struct virtual_mail *vmail = (struct virtual_mail *)mail;
    struct mail *backend_mail;
    int tz;

    if (timezone_r == NULL)
        timezone_r = &tz;

    if (backend_mail_get(vmail, &backend_mail) < 0)
        return -1;
    if (mail_get_date(backend_mail, date_r, timezone_r) < 0) {
        virtual_box_copy_error(mail->box, backend_mail->box);
        return -1;
    }
    return 0;
}

static int virtual_mail_get_received_date(struct mail *mail, time_t *date_r)
{
    struct virtual_mail *vmail = (struct virtual_mail *)mail;
    struct mail *backend_mail;

    if (backend_mail_get(vmail, &backend_mail) < 0)
        return -1;
    if (mail_get_received_date(backend_mail, date_r) < 0) {
        virtual_box_copy_error(mail->box, backend_mail->box);
        return -1;
    }
    return 0;
}

static int virtual_mail_get_save_date(struct mail *mail, time_t *date_r)
{
    struct virtual_mail *vmail = (struct virtual_mail *)mail;
    struct mail *backend_mail;

    if (backend_mail_get(vmail, &backend_mail) < 0)
        return -1;
    if (mail_get_save_date(backend_mail, date_r) < 0) {
        virtual_box_copy_error(mail->box, backend_mail->box);
        return -1;
    }
    return 0;
}

static int virtual_mail_get_virtual_mail_size(struct mail *mail, uoff_t *size_r)
{
    struct virtual_mail *vmail = (struct virtual_mail *)mail;
    struct mail *backend_mail;

    if (backend_mail_get(vmail, &backend_mail) < 0)
        return -1;
    if (mail_get_virtual_size(backend_mail, size_r) < 0) {
        virtual_box_copy_error(mail->box, backend_mail->box);
        return -1;
    }
    return 0;
}

static int virtual_mail_get_physical_size(struct mail *mail, uoff_t *size_r)
{
    struct virtual_mail *vmail = (struct virtual_mail *)mail;
    struct mail *backend_mail;

    if (backend_mail_get(vmail, &backend_mail) < 0)
        return -1;
    if (mail_get_physical_size(backend_mail, size_r) < 0) {
        virtual_box_copy_error(mail->box, backend_mail->box);
        return -1;
    }
    return 0;
}

static int
virtual_mail_get_first_header(struct mail *mail, const char *field,
                  bool decode_to_utf8, const char **value_r)
{
    struct virtual_mail *vmail = (struct virtual_mail *)mail;
    struct mail *backend_mail;
    struct mail_private *p;
    int ret;

    if (backend_mail_get(vmail, &backend_mail) < 0)
        return -1;
    p = (struct mail_private *)backend_mail;
    ret = p->v.get_first_header(backend_mail, field,
                    decode_to_utf8, value_r);
    if (ret < 0) {
        virtual_box_copy_error(mail->box, backend_mail->box);
        return -1;
    }
    return ret;
}

static int
virtual_mail_get_headers(struct mail *mail, const char *field,
             bool decode_to_utf8, const char *const **value_r)
{
    struct virtual_mail *vmail = (struct virtual_mail *)mail;
    struct mail *backend_mail;
    struct mail_private *p;

    if (backend_mail_get(vmail, &backend_mail) < 0)
        return -1;
    p = (struct mail_private *)backend_mail;
    if (p->v.get_headers(backend_mail, field, decode_to_utf8, value_r) < 0) {
        virtual_box_copy_error(mail->box, backend_mail->box);
        return -1;
    }
    return 0;
}

static int
virtual_mail_get_header_stream(struct mail *mail,
                   struct mailbox_header_lookup_ctx *headers,
                   struct istream **stream_r)
{
    struct virtual_mail *vmail = (struct virtual_mail *)mail;
    struct mail *backend_mail;
    struct mailbox_header_lookup_ctx *backend_headers;
    int ret;

    if (backend_mail_get(vmail, &backend_mail) < 0)
        return -1;

    backend_headers = mailbox_header_lookup_init(backend_mail->box,
                             headers->name);
    ret = mail_get_header_stream(backend_mail, backend_headers, stream_r);
    mailbox_header_lookup_unref(&backend_headers);
    if (ret < 0) {
        virtual_box_copy_error(mail->box, backend_mail->box);
        return -1;
    }
    return 0;
}

static int
virtual_mail_get_stream(struct mail *mail, bool get_body,
            struct message_size *hdr_size,
            struct message_size *body_size,
            struct istream **stream_r)
{
    struct virtual_mail *vmail = (struct virtual_mail *)mail;
    struct mail *backend_mail;
    int ret;

    if (backend_mail_get(vmail, &backend_mail) < 0)
        return -1;
    if (get_body) {
        ret = mail_get_stream(backend_mail, hdr_size, body_size,
                      stream_r);
    } else {
        ret = mail_get_hdr_stream(backend_mail, hdr_size, stream_r);
    }
    if (ret < 0) {
        virtual_box_copy_error(mail->box, backend_mail->box);
        return -1;
    }
    return 0;
}

static int
virtual_mail_get_special(struct mail *mail, enum mail_fetch_field field,
             const char **value_r)
{
    struct virtual_mail *vmail = (struct virtual_mail *)mail;
    struct mail *backend_mail;

    if (backend_mail_get(vmail, &backend_mail) < 0)
        return -1;
    if (mail_get_special(backend_mail, field, value_r) < 0) {
        virtual_box_copy_error(mail->box, backend_mail->box);
        return -1;
    }
    return 0;
}

static struct mail *virtual_mail_get_real_mail(struct mail *mail)
{
    struct virtual_mail *vmail = (struct virtual_mail *)mail;
    struct mail *backend_mail, *real_mail;

    if (backend_mail_get(vmail, &backend_mail) < 0)
        return NULL;

    if (mail_get_backend_mail(backend_mail, &real_mail) < 0)
        return NULL;
    return real_mail;
}

static void virtual_mail_update_pop3_uidl(struct mail *mail, const char *uidl)
{
    struct virtual_mail *vmail = (struct virtual_mail *)mail;
    struct mail *backend_mail;

    if (backend_mail_get(vmail, &backend_mail) < 0)
        return;
    mail_update_pop3_uidl(backend_mail, uidl);
}

static void virtual_mail_expunge(struct mail *mail)
{
    struct virtual_mail *vmail = (struct virtual_mail *)mail;
    struct mail *backend_mail;

    if (backend_mail_get(vmail, &backend_mail) < 0)
        return;
    mail_expunge(backend_mail);
}

static void
virtual_mail_set_cache_corrupted(struct mail *mail, enum mail_fetch_field field)
{
    struct virtual_mail *vmail = (struct virtual_mail *)mail;
    struct mail *backend_mail;

    if (backend_mail_get(vmail, &backend_mail) < 0)
        return;
    mail_set_cache_corrupted(backend_mail, field);
}

struct mail_vfuncs virtual_mail_vfuncs = {
    NULL,
    virtual_mail_free,
    virtual_mail_set_seq,
    virtual_mail_set_uid,
    virtual_mail_set_uid_cache_updates,
    virtual_mail_prefetch,
    virtual_mail_precache,
    virtual_mail_add_temp_wanted_fields,

    index_mail_get_flags,
    index_mail_get_keywords,
    index_mail_get_keyword_indexes,
    index_mail_get_modseq,
    index_mail_get_pvt_modseq,
    virtual_mail_get_parts,
    virtual_mail_get_date,
    virtual_mail_get_received_date,
    virtual_mail_get_save_date,
    virtual_mail_get_virtual_mail_size,
    virtual_mail_get_physical_size,
    virtual_mail_get_first_header,
    virtual_mail_get_headers,
    virtual_mail_get_header_stream,
    virtual_mail_get_stream,
    index_mail_get_binary_stream,
    virtual_mail_get_special,
    virtual_mail_get_real_mail,
    index_mail_update_flags,
    index_mail_update_keywords,
    index_mail_update_modseq,
    index_mail_update_pvt_modseq,
    virtual_mail_update_pop3_uidl,
    virtual_mail_expunge,
    virtual_mail_set_cache_corrupted,
    NULL
};