plugins/virtual/virtual-storage.c

	virtual-storage.c revision 77d8223da3da23b731257596abefa77e4485b77d
/* Copyright (c) 2008-2010 Dovecot authors, see the included COPYING file */

#include "lib.h"
#include "array.h"
#include "ioloop.h"
#include "str.h"
#include "mkdir-parents.h"
#include "unlink-directory.h"
#include "index-mail.h"
#include "mail-copy.h"
#include "mail-search.h"
#include "mailbox-list-private.h"
#include "virtual-plugin.h"
#include "virtual-transaction.h"
#include "virtual-storage.h"

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <dirent.h>
#include <sys/stat.h>

#define VIRTUAL_LIST_CONTEXT(obj) \
    MODULE_CONTEXT(obj, virtual_mailbox_list_module)

struct virtual_mailbox_list {
    union mailbox_list_module_context module_ctx;
};

extern struct mail_storage virtual_storage;
extern struct mailbox virtual_mailbox;

struct virtual_storage_module virtual_storage_module =
    MODULE_CONTEXT_INIT(&mail_storage_module_register);
static MODULE_CONTEXT_DEFINE_INIT(virtual_mailbox_list_module,
                  &mailbox_list_module_register);

static bool ns_is_visible(struct mail_namespace *ns)
{
    return (ns->flags & NAMESPACE_FLAG_LIST_PREFIX) != 0 ||
        (ns->flags & NAMESPACE_FLAG_LIST_CHILDREN) != 0 ||
        (ns->flags & NAMESPACE_FLAG_HIDDEN) == 0;
}

static const char *get_user_visible_mailbox_name(struct mailbox *box)
{
    if (ns_is_visible(box->list->ns))
        return box->vname;
    else {
        return t_strdup_printf("<hidden>%c%s",
                       box->list->hierarchy_sep, box->name);
    }
}

void virtual_box_copy_error(struct mailbox *dest, struct mailbox *src)
{
    const char *name, *str;
    enum mail_error error;

    name = get_user_visible_mailbox_name(src);
    str = mail_storage_get_last_error(src->storage, &error);

    str = t_strdup_printf("%s (for backend mailbox %s)", str, name);
    mail_storage_set_error(dest->storage, error, str);
}

static struct mail_storage *virtual_storage_alloc(void)
{
    struct virtual_storage *storage;
    pool_t pool;

    pool = pool_alloconly_create("virtual storage", 1024);
    storage = p_new(pool, struct virtual_storage, 1);
    storage->storage = virtual_storage;
    storage->storage.pool = pool;
    p_array_init(&storage->open_stack, pool, 8);
    return &storage->storage;
}

static void
virtual_storage_get_list_settings(const struct mail_namespace *ns ATTR_UNUSED,
                  struct mailbox_list_settings *set)
{
    if (set->layout == NULL)
        set->layout = MAILBOX_LIST_NAME_FS;
    if (set->subscription_fname == NULL)
        set->subscription_fname = VIRTUAL_SUBSCRIPTION_FILE_NAME;
}

struct virtual_backend_box *
virtual_backend_box_lookup_name(struct virtual_mailbox *mbox, const char *name)
{
    struct virtual_backend_box *const *bboxes;
    unsigned int i, count;

    bboxes = array_get(&mbox->backend_boxes, &count);
    for (i = 0; i < count; i++) {
        if (strcmp(bboxes[i]->name, name) == 0)
            return bboxes[i];
    }
    return NULL;
}

struct virtual_backend_box *
virtual_backend_box_lookup(struct virtual_mailbox *mbox, uint32_t mailbox_id)
{
    struct virtual_backend_box *const *bboxes;
    unsigned int i, count;

    if (mailbox_id == 0)
        return NULL;

    bboxes = array_get(&mbox->backend_boxes, &count);
    for (i = 0; i < count; i++) {
        if (bboxes[i]->mailbox_id == mailbox_id)
            return bboxes[i];
    }
    return NULL;
}

static bool virtual_mailbox_is_in_open_stack(struct virtual_storage *storage,
                         const char *name)
{
    const char *const *names;
    unsigned int i, count;

    names = array_get(&storage->open_stack, &count);
    for (i = 0; i < count; i++) {
        if (strcmp(names[i], name) == 0)
            return TRUE;
    }
    return FALSE;
}

static int virtual_backend_box_open_failed(struct virtual_mailbox *mbox,
                       struct virtual_backend_box *bbox)
{
    enum mail_error error;
    const char *str, *name;

    str = mail_storage_get_last_error(mailbox_get_storage(bbox->box),
                      &error);
    name = t_strdup(get_user_visible_mailbox_name(bbox->box));
    mailbox_free(&bbox->box);
    if (bbox->wildcard &&
        (error == MAIL_ERROR_PERM || error == MAIL_ERROR_NOTFOUND)) {
        /* this mailbox wasn't explicitly specified. just skip it. */
        return 0;
    }

    if (error == MAIL_ERROR_NOTFOUND) {
        /* the virtual mailbox exists, we just can't open it.
           change the error type. */
        error = MAIL_ERROR_NOTPOSSIBLE;
    }
    str = t_strdup_printf(
        "Virtual mailbox open failed because of mailbox %s: %s",
        name, str);
    mail_storage_set_error(mbox->box.storage, error, str);
    return -1;
}

static int virtual_backend_box_open(struct virtual_mailbox *mbox,
                    struct virtual_backend_box *bbox,
                    enum mailbox_flags flags)
{
    struct mail_user *user = mbox->storage->storage.user;
    struct mail_namespace *ns;
    const char *mailbox;

    i_assert(bbox->box == NULL);

    flags |= MAILBOX_FLAG_KEEP_RECENT;

    mailbox = bbox->name;
    ns = mail_namespace_find(user->namespaces, &mailbox);
    bbox->box = mailbox_alloc(ns->list, mailbox, flags);

    if (mailbox_open(bbox->box) < 0)
        return virtual_backend_box_open_failed(mbox, bbox);
    i_array_init(&bbox->uids, 64);
    i_array_init(&bbox->sync_pending_removes, 64);
    mail_search_args_init(bbox->search_args, bbox->box, FALSE, NULL);
    return 1;
}

static int virtual_mailboxes_open(struct virtual_mailbox *mbox,
                  enum mailbox_flags flags)
{
    struct virtual_backend_box *const *bboxes;
    unsigned int i, count;
    int ret;

    bboxes = array_get(&mbox->backend_boxes, &count);
    for (i = 0; i < count; ) {
        ret = virtual_backend_box_open(mbox, bboxes[i], flags);
        if (ret <= 0) {
            if (ret < 0)
                break;
            mail_search_args_unref(&bboxes[i]->search_args);
            array_delete(&mbox->backend_boxes, i, 1);
            bboxes = array_get(&mbox->backend_boxes, &count);
        } else {
            i++;
        }
    }
    if (i == count)
        return 0;
    else {
        /* failed */
        for (; i > 0; i--) {
            mailbox_free(&bboxes[i-1]->box);
            array_free(&bboxes[i-1]->uids);
        }
        return -1;
    }
}

static struct mailbox *
virtual_mailbox_alloc(struct mail_storage *_storage, struct mailbox_list *list,
              const char *name, enum mailbox_flags flags)
{
    struct virtual_storage *storage = (struct virtual_storage *)_storage;
    struct virtual_mailbox *mbox;
    pool_t pool;

    pool = pool_alloconly_create("virtual mailbox", 1024+512);
    mbox = p_new(pool, struct virtual_mailbox, 1);
    mbox->box = virtual_mailbox;
    mbox->box.pool = pool;
    mbox->box.storage = _storage;
    mbox->box.list = list;
    mbox->box.mail_vfuncs = &virtual_mail_vfuncs;

    index_storage_mailbox_alloc(&mbox->box, name, flags,
                    VIRTUAL_INDEX_PREFIX);

    mbox->storage = storage;
    mbox->vseq_lookup_prev_mailbox = i_strdup("");

    mbox->virtual_ext_id =
        mail_index_ext_register(mbox->box.index, "virtual", 0,
            sizeof(struct virtual_mail_index_record),
            sizeof(uint32_t));
    return &mbox->box;
}

static void virtual_mailbox_close_internal(struct virtual_mailbox *mbox)
{
    struct virtual_backend_box **bboxes;
    unsigned int i, count;

    bboxes = array_get_modifiable(&mbox->backend_boxes, &count);
    for (i = 0; i < count; i++) {
        if (bboxes[i]->search_result != NULL)
            mailbox_search_result_free(&bboxes[i]->search_result);

        if (bboxes[i]->box == NULL)
            continue;

        mail_search_args_deinit(bboxes[i]->search_args);
        mailbox_free(&bboxes[i]->box);
        if (array_is_created(&bboxes[i]->sync_outside_expunges))
            array_free(&bboxes[i]->sync_outside_expunges);
        array_free(&bboxes[i]->sync_pending_removes);
        array_free(&bboxes[i]->uids);
    }
    i_free_and_null(mbox->vseq_lookup_prev_mailbox);
}

static int virtual_mailbox_open(struct mailbox *box)
{
    struct virtual_mailbox *mbox = (struct virtual_mailbox *)box;
    struct stat st;
    int ret = 0;

    if (virtual_mailbox_is_in_open_stack(mbox->storage, box->name)) {
        mail_storage_set_critical(box->storage,
            "Virtual mailbox loops: %s", box->name);
        return -1;
    }

    if (stat(box->path, &st) == 0) {
        /* exists, open it */
    } else if (errno == ENOENT) {
        mail_storage_set_error(box->storage, MAIL_ERROR_NOTFOUND,
            T_MAIL_ERR_MAILBOX_NOT_FOUND(box->name));
        return -1;
    } else if (errno == EACCES) {
        mail_storage_set_critical(box->storage, "%s",
            mail_error_eacces_msg("stat", box->path));
        return -1;
    } else {
        mail_storage_set_critical(box->storage,
                      "stat(%s) failed: %m", box->path);
        return -1;
    }

    if (!array_is_created(&mbox->backend_boxes))
        ret = virtual_config_read(mbox);
    if (ret == 0) {
        array_append(&mbox->storage->open_stack, &box->name, 1);
        ret = virtual_mailboxes_open(mbox, box->flags);
        array_delete(&mbox->storage->open_stack,
                 array_count(&mbox->storage->open_stack)-1, 1);
    }

    if (ret < 0) {
        virtual_mailbox_close_internal(mbox);
        return -1;
    }
    return index_storage_mailbox_open(box, FALSE);
}

static void virtual_mailbox_close(struct mailbox *box)
{
    struct virtual_mailbox *mbox = (struct virtual_mailbox *)box;

    virtual_mailbox_close_internal(mbox);
    index_storage_mailbox_close(box);
}

static void virtual_mailbox_free(struct mailbox *box)
{
    struct virtual_mailbox *mbox = (struct virtual_mailbox *)box;

    virtual_config_free(mbox);
    index_storage_mailbox_free(box);
}

static int
virtual_mailbox_create(struct mailbox *box,
               const struct mailbox_update *update ATTR_UNUSED,
               bool directory ATTR_UNUSED)
{
    mail_storage_set_error(box->storage, MAIL_ERROR_NOTPOSSIBLE,
                   "Can't create virtual mailboxes");
    return -1;
}

static int
virtual_mailbox_update(struct mailbox *box,
               const struct mailbox_update *update ATTR_UNUSED)
{
    mail_storage_set_error(box->storage, MAIL_ERROR_NOTPOSSIBLE,
                   "Can't update virtual mailboxes");
    return -1;
}

static int
virtual_mailbox_get_guid(struct mailbox *box,
             uint8_t guid[MAIL_GUID_128_SIZE] ATTR_UNUSED)
{
    mail_storage_set_error(box->storage, MAIL_ERROR_NOTPOSSIBLE,
                   "Virtual mailboxes have no GUIDs");
    return -1;
}

static void
virtual_notify_callback(struct mailbox *bbox ATTR_UNUSED, struct mailbox *box)
{
    box->notify_callback(box, box->notify_context);
}

static void virtual_notify_changes(struct mailbox *box)
{
    struct virtual_mailbox *mbox = (struct virtual_mailbox *)box;
    struct virtual_backend_box *const *bboxes;
    unsigned int i, count;

    bboxes = array_get(&mbox->backend_boxes, &count);
    for (i = 0; i < count; i++) {
        struct mailbox *bbox = bboxes[i]->box;

        if (box->notify_callback == NULL)
            mailbox_notify_changes_stop(bbox);
        else {
            mailbox_notify_changes(bbox, box->notify_min_interval,
                           virtual_notify_callback, box);
        }
    }
}

static int
virtual_list_get_mailbox_flags(struct mailbox_list *list,
                   const char *dir, const char *fname,
                   enum mailbox_list_file_type type,
                   struct stat *st_r,
                   enum mailbox_info_flags *flags)
{
    struct virtual_mailbox_list *mlist = VIRTUAL_LIST_CONTEXT(list);
    struct stat st2;
    const char *virtual_path;
    int ret;

    ret = mlist->module_ctx.super.
        get_mailbox_flags(list, dir, fname, type, st_r, flags);
    if (ret <= 0 || MAILBOX_INFO_FLAGS_FINISHED(*flags))
        return ret;

    /* see if it's a selectable mailbox */
    virtual_path = t_strconcat(dir, "/", fname, "/"VIRTUAL_CONFIG_FNAME,
                   NULL);
    if (stat(virtual_path, &st2) < 0)
        *flags |= MAILBOX_NOSELECT;
    return ret;
}

static void virtual_storage_add_list(struct mail_storage *storage ATTR_UNUSED,
                     struct mailbox_list *list)
{
    struct mailbox_list_vfuncs *v = list->vlast;
    struct virtual_mailbox_list *mlist;

    mlist = p_new(list->pool, struct virtual_mailbox_list, 1);
    mlist->module_ctx.super = *v;
    list->vlast = &mlist->module_ctx.super;

    list->ns->flags |= NAMESPACE_FLAG_NOQUOTA;
    v->get_mailbox_flags = virtual_list_get_mailbox_flags;

    MODULE_CONTEXT_SET(list, virtual_mailbox_list_module, mlist);
}

static int virtual_backend_uidmap_cmp(const uint32_t *uid,
                      const struct virtual_backend_uidmap *map)
{
    return *uid < map->real_uid ? -1 :
        *uid > map->real_uid ? 1 : 0;
}

static bool
virtual_get_virtual_uid(struct mailbox *box, const char *backend_mailbox,
            uint32_t backend_uidvalidity,
            uint32_t backend_uid, uint32_t *uid_r)
{
    struct virtual_mailbox *mbox = (struct virtual_mailbox *)box;
    struct virtual_backend_box *bbox;
    struct mailbox_status status;
    const struct virtual_backend_uidmap *uids;

    if (strcmp(mbox->vseq_lookup_prev_mailbox, backend_mailbox) == 0)
        bbox = mbox->vseq_lookup_prev_bbox;
    else {
        i_free(mbox->vseq_lookup_prev_mailbox);
        mbox->vseq_lookup_prev_mailbox = i_strdup(backend_mailbox);

        bbox = virtual_backend_box_lookup_name(mbox, backend_mailbox);
        mbox->vseq_lookup_prev_bbox = bbox;
    }
    if (bbox == NULL)
        return FALSE;

    mailbox_get_status(bbox->box, STATUS_UIDVALIDITY, &status);
    if (status.uidvalidity != backend_uidvalidity)
        return FALSE;

    uids = array_bsearch(&bbox->uids, &backend_uid,
                 virtual_backend_uidmap_cmp);
    if (uids == NULL)
        return FALSE;

    *uid_r = uids->virtual_uid;
    return TRUE;
}

static void
virtual_get_virtual_backend_boxes(struct mailbox *box,
                  ARRAY_TYPE(mailboxes) *mailboxes,
                  bool only_with_msgs)
{
    struct virtual_mailbox *mbox = (struct virtual_mailbox *)box;
    struct virtual_backend_box *const *bboxes;
    unsigned int i, count;

    bboxes = array_get(&mbox->backend_boxes, &count);
    for (i = 0; i < count; i++) {
        if (!only_with_msgs || array_count(&bboxes[i]->uids) > 0)
            array_append(mailboxes, &bboxes[i]->box, 1);
    }
}

static void
virtual_get_virtual_box_patterns(struct mailbox *box,
                 ARRAY_TYPE(mailbox_virtual_patterns) *includes,
                 ARRAY_TYPE(mailbox_virtual_patterns) *excludes)
{
    struct virtual_mailbox *mbox = (struct virtual_mailbox *)box;

    array_append_array(includes, &mbox->list_include_patterns);
    array_append_array(excludes, &mbox->list_exclude_patterns);
}

static bool virtual_is_inconsistent(struct mailbox *box)
{
    struct virtual_mailbox *mbox = (struct virtual_mailbox *)box;

    if (mbox->inconsistent)
        return TRUE;

    return index_storage_is_inconsistent(box);
}

struct mail_storage virtual_storage = {
    .name = VIRTUAL_STORAGE_NAME,
    .class_flags = 0,

    .v = {
        NULL,
        virtual_storage_alloc,
        NULL,
        NULL,
        virtual_storage_add_list,
        virtual_storage_get_list_settings,
        NULL,
        virtual_mailbox_alloc,
        NULL
    }
};

struct mailbox virtual_mailbox = {
    .v = {
        index_storage_is_readonly,
        index_storage_allow_new_keywords,
        index_storage_mailbox_enable,
        virtual_mailbox_open,
        virtual_mailbox_close,
        virtual_mailbox_free,
        virtual_mailbox_create,
        virtual_mailbox_update,
        index_storage_mailbox_delete,
        index_storage_mailbox_rename,
        index_storage_get_status,
        virtual_mailbox_get_guid,
        NULL,
        NULL,
        virtual_storage_sync_init,
        index_mailbox_sync_next,
        index_mailbox_sync_deinit,
        NULL,
        virtual_notify_changes,
        virtual_transaction_begin,
        virtual_transaction_commit,
        virtual_transaction_rollback,
        index_transaction_set_max_modseq,
        index_keywords_create,
        index_keywords_create_from_indexes,
        index_keywords_ref,
        index_keywords_unref,
        index_keyword_is_valid,
        index_storage_get_seq_range,
        index_storage_get_uid_range,
        index_storage_get_expunges,
        virtual_get_virtual_uid,
        virtual_get_virtual_backend_boxes,
        virtual_get_virtual_box_patterns,
        virtual_mail_alloc,
        index_header_lookup_init,
        index_header_lookup_deinit,
        virtual_search_init,
        virtual_search_deinit,
        virtual_search_next_nonblock,
        virtual_search_next_update_seq,
        virtual_save_alloc,
        virtual_save_begin,
        virtual_save_continue,
        virtual_save_finish,
        virtual_save_cancel,
        mail_storage_copy,
        virtual_is_inconsistent
    }
};