src/lib-storage/mail-namespace.c

	mail-namespace.c revision 98b27a037e337fdd3965469884245b409e3a1e84
02c335c23bf5fa225a467c19f2c063fb0dc7b8c3Timo Sirainen/* Copyright (c) 2005-2010 Dovecot authors, see the included COPYING file */
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen#include "lib.h"
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen#include "array.h"
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen#include "str.h"
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen#include "file-lock.h"
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen#include "mailbox-list-private.h"
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen#include "mail-storage-private.h"
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen#include "mail-storage-settings.h"
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen#include "mail-namespace.h"
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen#include <stdlib.h>
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainenvoid mail_namespace_add_storage(struct mail_namespace *ns,
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen                struct mail_storage *storage)
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen{
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen    /* currently we support only a single storage */
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen    i_assert(ns->storage == NULL);
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen    ns->storage = storage;
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen    if (storage->v.add_list != NULL)
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen        storage->v.add_list(storage, ns->list);
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen    hook_mail_namespace_storage_added(ns);
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen}
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainenvoid mail_namespace_finish_list_init(struct mail_namespace *ns,
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen                     struct mailbox_list *list)
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen{
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen    ns->list = list;
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen    /* allow plugins to override real_sep */
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen    if (ns->real_sep == '\0')
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen        ns->real_sep = list->hierarchy_sep;
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen    ns->prefix_len = strlen(ns->prefix);
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen    if (ns->set->separator != NULL)
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen        ns->sep = *ns->set->separator;
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen    if (ns->sep == '\0')
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen                ns->sep = ns->real_sep;
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen    if (ns->sep == '"' || ns->sep == '\\') {
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen        ns->sep_str[0] = '\\';
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen        ns->sep_str[1] = ns->sep;
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen    } else {
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen        ns->sep_str[0] = ns->sep;
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen    }
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen}
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainenstatic void mail_namespace_free(struct mail_namespace *ns)
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen{
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen    if (ns->storage != NULL)
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen        mail_storage_unref(&ns->storage);
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen    if (ns->list != NULL)
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen        mailbox_list_destroy(&ns->list);
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen    if (ns->owner != ns->user && ns->owner != NULL)
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen        mail_user_unref(&ns->owner);
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen    i_free(ns->prefix);
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen    i_free(ns);
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen}
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainenstatic int
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainennamespace_add(struct mail_user *user,
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen          struct mail_namespace_settings *ns_set,
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen          struct mail_namespace_settings *unexpanded_ns_set,
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen          const struct mail_storage_settings *mail_set,
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen          struct mail_namespace **ns_p, const char **error_r)
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen{
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen        struct mail_namespace *ns;
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen    const char *driver, *error;
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen    ns = i_new(struct mail_namespace, 1);
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen    ns->refcount = 1;
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen    ns->user = user;
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen    if (strncmp(ns_set->type, "private", 7) == 0) {
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen        ns->owner = user;
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen        ns->type = NAMESPACE_PRIVATE;
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen    } else if (strncmp(ns_set->type, "shared", 6) == 0)
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen        ns->type = NAMESPACE_SHARED;
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen    else if (strncmp(ns_set->type, "public", 6) == 0)
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen        ns->type = NAMESPACE_PUBLIC;
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen    else {
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen        *error_r = t_strdup_printf("Unknown namespace type: %s",
209335fbc1a5fe68e662242ea91e236fdb2ba29dTimo Sirainen                       ns_set->type);
209335fbc1a5fe68e662242ea91e236fdb2ba29dTimo Sirainen        mail_namespace_free(ns);
209335fbc1a5fe68e662242ea91e236fdb2ba29dTimo Sirainen        return -1;
209335fbc1a5fe68e662242ea91e236fdb2ba29dTimo Sirainen    }
209335fbc1a5fe68e662242ea91e236fdb2ba29dTimo Sirainen
209335fbc1a5fe68e662242ea91e236fdb2ba29dTimo Sirainen    if (strcmp(ns_set->list, "children") == 0)
209335fbc1a5fe68e662242ea91e236fdb2ba29dTimo Sirainen        ns->flags |= NAMESPACE_FLAG_LIST_CHILDREN;
209335fbc1a5fe68e662242ea91e236fdb2ba29dTimo Sirainen    else if (strcmp(ns_set->list, "yes") == 0)
209335fbc1a5fe68e662242ea91e236fdb2ba29dTimo Sirainen        ns->flags |= NAMESPACE_FLAG_LIST_PREFIX;
209335fbc1a5fe68e662242ea91e236fdb2ba29dTimo Sirainen    else if (strcmp(ns_set->list, "no") != 0) {
209335fbc1a5fe68e662242ea91e236fdb2ba29dTimo Sirainen        *error_r = t_strdup_printf("Invalid list setting value: %s",
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen                       ns_set->list);
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen        mail_namespace_free(ns);
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen        return -1;
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen    }
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen    if (ns_set->inbox) {
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen        ns->flags |= NAMESPACE_FLAG_INBOX_USER |
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen            NAMESPACE_FLAG_INBOX_ANY;
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen    }
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen    if (ns_set->hidden)
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen        ns->flags |= NAMESPACE_FLAG_HIDDEN;
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen    if (ns_set->subscriptions)
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen        ns->flags |= NAMESPACE_FLAG_SUBSCRIPTIONS;
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen    if (*ns_set->location == '\0')
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen        ns_set->location = mail_set->mail_location;
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen    if (mail_set->mail_debug) {
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen        i_debug("Namespace %s: type=%s, prefix=%s, sep=%s, "
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen            "inbox=%s, hidden=%s, list=%s, subscriptions=%s "
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen            "location=%s",
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen            ns_set->name, ns_set->type, ns_set->prefix,
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen            ns_set->separator == NULL ? "" : ns_set->separator,
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen            ns_set->inbox ? "yes" : "no",
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen            ns_set->hidden ? "yes" : "no",
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen            ns_set->list,
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen            ns_set->subscriptions ? "yes" : "no", ns_set->location);
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen    }
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen    ns->set = ns_set;
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen    ns->unexpanded_set = unexpanded_ns_set;
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen    ns->mail_set = mail_set;
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen    ns->prefix = i_strdup(ns_set->prefix);
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen    if (ns->type == NAMESPACE_SHARED &&
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen        (strchr(ns->prefix, '%') != NULL ||
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen         strchr(ns->set->location, '%') != NULL)) {
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen        /* dynamic shared namespace. the above check catches wrong
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen           mixed %% usage, but still allows for specifying a shared
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen           namespace to an explicit location without any %% */
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen        ns->flags |= NAMESPACE_FLAG_NOQUOTA | NAMESPACE_FLAG_NOACL;
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen        driver = "shared";
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen    } else {
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen        driver = NULL;
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen    }
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen    if (mail_storage_create(ns, driver, 0, &error) < 0) {
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen        *error_r = t_strdup_printf("Namespace '%s': %s",
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen                       ns->prefix, error);
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen        mail_namespace_free(ns);
a893aaa999856b1ba6e4541890016767aaa283c7Aki Tuomi        return -1;
a893aaa999856b1ba6e4541890016767aaa283c7Aki Tuomi    }
a893aaa999856b1ba6e4541890016767aaa283c7Aki Tuomi
a893aaa999856b1ba6e4541890016767aaa283c7Aki Tuomi    *ns_p = ns;
a893aaa999856b1ba6e4541890016767aaa283c7Aki Tuomi    return 0;
a893aaa999856b1ba6e4541890016767aaa283c7Aki Tuomi}
2d83aa5eebd1bb710ca2fc21316b89442f027f3dAki Tuomi
2d83aa5eebd1bb710ca2fc21316b89442f027f3dAki Tuomistatic bool namespace_is_valid_alias_storage(struct mail_namespace *ns,
a893aaa999856b1ba6e4541890016767aaa283c7Aki Tuomi                         const char **error_r)
a893aaa999856b1ba6e4541890016767aaa283c7Aki Tuomi{
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen    if (strcmp(ns->storage->name, ns->alias_for->storage->name) != 0) {
a893aaa999856b1ba6e4541890016767aaa283c7Aki Tuomi        *error_r = t_strdup_printf(
a893aaa999856b1ba6e4541890016767aaa283c7Aki Tuomi            "Namespace %s can't have alias_for=%s "
a893aaa999856b1ba6e4541890016767aaa283c7Aki Tuomi            "to a different storage type (%s vs %s)",
a893aaa999856b1ba6e4541890016767aaa283c7Aki Tuomi            ns->prefix, ns->alias_for->prefix,
a893aaa999856b1ba6e4541890016767aaa283c7Aki Tuomi            ns->storage->name, ns->alias_for->storage->name);
a893aaa999856b1ba6e4541890016767aaa283c7Aki Tuomi        return FALSE;
a893aaa999856b1ba6e4541890016767aaa283c7Aki Tuomi    }
2d83aa5eebd1bb710ca2fc21316b89442f027f3dAki Tuomi
2d83aa5eebd1bb710ca2fc21316b89442f027f3dAki Tuomi    if ((ns->storage->class_flags & MAIL_STORAGE_CLASS_FLAG_UNIQUE_ROOT) != 0 &&
a893aaa999856b1ba6e4541890016767aaa283c7Aki Tuomi        ns->storage != ns->alias_for->storage) {
a893aaa999856b1ba6e4541890016767aaa283c7Aki Tuomi        *error_r = t_strdup_printf(
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen            "Namespace %s can't have alias_for=%s "
a893aaa999856b1ba6e4541890016767aaa283c7Aki Tuomi            "to a different storage (different root dirs)",
a893aaa999856b1ba6e4541890016767aaa283c7Aki Tuomi            ns->prefix, ns->alias_for->prefix);
a893aaa999856b1ba6e4541890016767aaa283c7Aki Tuomi        return FALSE;
a893aaa999856b1ba6e4541890016767aaa283c7Aki Tuomi    }
a893aaa999856b1ba6e4541890016767aaa283c7Aki Tuomi    return TRUE;
a893aaa999856b1ba6e4541890016767aaa283c7Aki Tuomi}
a893aaa999856b1ba6e4541890016767aaa283c7Aki Tuomi
2d83aa5eebd1bb710ca2fc21316b89442f027f3dAki Tuomistatic int
2d83aa5eebd1bb710ca2fc21316b89442f027f3dAki Tuominamespace_set_alias_for(struct mail_namespace *ns,
a893aaa999856b1ba6e4541890016767aaa283c7Aki Tuomi            struct mail_namespace *all_namespaces,
a893aaa999856b1ba6e4541890016767aaa283c7Aki Tuomi            const char **error_r)
6eb7938cd366fc087b39fc9a901e7de426131384Timo Sirainen{
    if (ns->set->alias_for != NULL) {
        ns->alias_for = mail_namespace_find_prefix(all_namespaces,
                               ns->set->alias_for);
        if (ns->alias_for == NULL) {
            *error_r = t_strdup_printf("Invalid namespace alias_for: %s",
                           ns->set->alias_for);
            return -1;
        }
        if (ns->alias_for->alias_for != NULL) {
            *error_r = t_strdup_printf("Chained namespace alias_for: %s",
                           ns->set->alias_for);
            return -1;
        }
        if (!namespace_is_valid_alias_storage(ns, error_r))
            return -1;

        ns->alias_chain_next = ns->alias_for->alias_chain_next;
        ns->alias_for->alias_chain_next = ns;
    }
    return 0;
}

static bool
namespaces_check(struct mail_namespace *namespaces, const char **error_r)
{
    struct mail_namespace *ns, *inbox_ns = NULL;
    unsigned int subscriptions_count = 0;
    char list_sep = '\0';

    for (ns = namespaces; ns != NULL; ns = ns->next) {
        if (mail_namespace_find_prefix(ns->next, ns->prefix) != NULL) {
            *error_r = t_strdup_printf(
                "Duplicate namespace prefix: \"%s\"",
                ns->prefix);
            return FALSE;
        }
        if (namespace_set_alias_for(ns, namespaces, error_r) < 0)
            return FALSE;
        if ((ns->flags & NAMESPACE_FLAG_INBOX_USER) != 0) {
            if (inbox_ns != NULL) {
                *error_r = "There can be only one namespace with "
                    "inbox=yes";
                return FALSE;
            }
            inbox_ns = ns;
        }
        if (*ns->prefix != '\0' &&
            (ns->flags & (NAMESPACE_FLAG_LIST_PREFIX |
                  NAMESPACE_FLAG_LIST_CHILDREN)) != 0 &&
            ns->prefix[strlen(ns->prefix)-1] != ns->sep) {
            *error_r = t_strdup_printf(
                "list=yes requires prefix=%s "
                "to end with separator", ns->prefix);
            return FALSE;
        }
        if (*ns->prefix != '\0' &&
            (ns->flags & (NAMESPACE_FLAG_LIST_PREFIX |
                  NAMESPACE_FLAG_LIST_CHILDREN)) != 0 &&
            ns->prefix[0] == ns->sep) {
            *error_r = t_strdup_printf(
                "list=yes requires prefix=%s "
                "not to start with separator", ns->prefix);
            return FALSE;
        }
        if ((ns->flags & (NAMESPACE_FLAG_LIST_PREFIX |
                  NAMESPACE_FLAG_LIST_CHILDREN)) != 0) {
            if (list_sep == '\0')
                list_sep = ns->sep;
            else if (list_sep != ns->sep) {
                *error_r = "All list=yes namespaces must use "
                    "the same separator";
                return FALSE;
            }
        }
        if ((ns->flags & NAMESPACE_FLAG_SUBSCRIPTIONS) != 0)
            subscriptions_count++;
    }

    if (inbox_ns == NULL) {
        *error_r = "inbox=yes namespace missing";
        return FALSE;
    }
    if (list_sep == '\0') {
        *error_r = "no list=yes namespaces";
        return FALSE;
    }
    if (subscriptions_count == 0) {
        *error_r = "no subscriptions=yes namespaces";
        return FALSE;
    }
    return TRUE;
}

int mail_namespaces_init(struct mail_user *user, const char **error_r)
{
    const struct mail_storage_settings *mail_set, *unexpanded_mail_set;
    struct mail_namespace_settings *const *ns_set;
    struct mail_namespace_settings *const *unexpanded_ns_set;
    struct mail_namespace *namespaces, *ns, **ns_p;
    struct mail_namespace_settings *inbox_set, *unexpanded_inbox_set;
    const char *error, *driver, *location_source;
    unsigned int i, count, count2;

    i_assert(user->initialized);

        namespaces = NULL; ns_p = &namespaces;

    mail_set = mail_user_set_get_storage_set(user);
    if (array_is_created(&user->set->namespaces)) {
        ns_set = array_get(&user->set->namespaces, &count);
        unexpanded_ns_set =
            array_get(&user->unexpanded_set->namespaces, &count2);
        i_assert(count == count2);
    } else {
        ns_set = unexpanded_ns_set = NULL;
        count = 0;
    }
    for (i = 0; i < count; i++) {
        if (namespace_add(user, ns_set[i], unexpanded_ns_set[i],
                  mail_set, ns_p, error_r) < 0)
            return -1;
        ns_p = &(*ns_p)->next;
    }

    if (namespaces != NULL) {
        if (!namespaces_check(namespaces, error_r)) {
            *error_r = t_strconcat("namespace configuration error: ",
                           *error_r, NULL);
            while (namespaces != NULL) {
                ns = namespaces;
                namespaces = ns->next;
                mail_namespace_free(ns);
            }
            return -1;
        }
        mail_user_add_namespace(user, &namespaces);

        T_BEGIN {
            hook_mail_namespaces_created(namespaces);
        } T_END;
        return 0;
    }

    /* no namespaces defined, create a default one */
    ns = i_new(struct mail_namespace, 1);
    ns->refcount = 1;
    ns->type = NAMESPACE_PRIVATE;
    ns->flags = NAMESPACE_FLAG_INBOX_USER | NAMESPACE_FLAG_INBOX_ANY |
        NAMESPACE_FLAG_LIST_PREFIX | NAMESPACE_FLAG_SUBSCRIPTIONS;
    ns->owner = user;

    inbox_set = p_new(user->pool, struct mail_namespace_settings, 1);
    *inbox_set = mail_namespace_default_settings;
    inbox_set->inbox = TRUE;

    unexpanded_inbox_set = p_new(user->pool, struct mail_namespace_settings, 1);
    *unexpanded_inbox_set = *inbox_set;

    driver = NULL;
    if (*mail_set->mail_location != '\0') {
        unexpanded_mail_set = mail_user_set_get_driver_settings(
            user->set_info, user->unexpanded_set,
            MAIL_STORAGE_SET_DRIVER_NAME);

        inbox_set->location = mail_set->mail_location;
        unexpanded_inbox_set->location =
            unexpanded_mail_set->mail_location;
        location_source = "mail_location setting";
    } else {
        location_source = "environment MAIL";
        inbox_set->location = getenv("MAIL");
    }
    if (inbox_set->location == NULL) {
        /* support also maildir-specific environment */
        inbox_set->location = getenv("MAILDIR");
        if (inbox_set->location == NULL)
            inbox_set->location = "";
        else {
            driver = "maildir";
            location_source = "environment MAILDIR";
        }
    }

    if (unexpanded_inbox_set->location == NULL)
        unexpanded_inbox_set->location = inbox_set->location;

    ns->set = inbox_set;
    ns->unexpanded_set = unexpanded_inbox_set;
    ns->mail_set = mail_set;
    ns->prefix = i_strdup(ns->set->prefix);
    ns->user = user;

    if (mail_storage_create(ns, driver, 0, &error) < 0) {
        if (*inbox_set->location != '\0') {
            *error_r = t_strdup_printf(
                "Initializing mail storage from %s "
                "failed: %s", location_source, error);
        } else {
            *error_r = t_strdup_printf("mail_location not set and "
                    "autodetection failed: %s", error);
        }
        mail_namespace_free(ns);
        return -1;
    }
    user->namespaces = ns;

    if (hook_mail_namespaces_created != NULL) {
        T_BEGIN {
            hook_mail_namespaces_created(ns);
        } T_END;
    }
    return 0;
}

struct mail_namespace *mail_namespaces_init_empty(struct mail_user *user)
{
    struct mail_namespace *ns;

    ns = i_new(struct mail_namespace, 1);
    ns->refcount = 1;
    ns->user = user;
    ns->owner = user;
    ns->prefix = i_strdup("");
    ns->flags = NAMESPACE_FLAG_INBOX_USER | NAMESPACE_FLAG_INBOX_ANY |
        NAMESPACE_FLAG_LIST_PREFIX | NAMESPACE_FLAG_SUBSCRIPTIONS;
    ns->mail_set = mail_user_set_get_storage_set(user);
    user->namespaces = ns;
    return ns;
}

void mail_namespaces_deinit(struct mail_namespace **_namespaces)
{
    struct mail_namespace *ns, *next;

    /* update *_namespaces as needed, instead of immediately setting it
       to NULL. for example mdbox_storage.destroy() wants to go through
       user's namespaces. */
    while (*_namespaces != NULL) {
        ns = *_namespaces;
        next = ns->next;

        mail_namespace_free(ns);
        *_namespaces = next;
    }
}

void mail_namespaces_set_storage_callbacks(struct mail_namespace *namespaces,
                       struct mail_storage_callbacks *callbacks,
                       void *context)
{
    struct mail_namespace *ns;

    for (ns = namespaces; ns != NULL; ns = ns->next)
        mail_storage_set_callbacks(ns->storage, callbacks, context);
}

void mail_namespace_ref(struct mail_namespace *ns)
{
    i_assert(ns->refcount > 0);

    ns->refcount++;
}

void mail_namespace_unref(struct mail_namespace **_ns)
{
    struct mail_namespace *ns = *_ns;

    i_assert(ns->refcount > 0);

    *_ns = NULL;

    if (--ns->refcount > 0)
        return;

    i_assert(ns->destroyed);
    mail_namespace_free(ns);
}

void mail_namespace_destroy(struct mail_namespace *ns)
{
    struct mail_namespace **nsp;

    i_assert(!ns->destroyed);

    /* remove from user's namespaces list */
    for (nsp = &ns->user->namespaces; *nsp != NULL; nsp = &(*nsp)->next) {
        if (*nsp == ns) {
            *nsp = ns->next;
            break;
        }
    }
    ns->destroyed = TRUE;

    mail_namespace_unref(&ns);
}

const char *mail_namespace_fix_sep(struct mail_namespace *ns, const char *name)
{
    char *ret, *p;

    if (ns->sep == ns->real_sep)
        return name;
    if (ns->type == NAMESPACE_SHARED &&
        (ns->flags & NAMESPACE_FLAG_AUTOCREATED) == 0) {
        /* shared namespace root. the backend storage's hierarchy
           separator isn't known yet, so do nothing. */
        return name;
    }

    ret = p_strdup(unsafe_data_stack_pool, name);
    for (p = ret; *p != '\0'; p++) {
        if (*p == ns->sep)
            *p = ns->real_sep;
    }
    return ret;
}

const char *mail_namespace_get_storage_name(struct mail_namespace *ns,
                        const char *name)
{
    unsigned int len = strlen(ns->prefix);

    if (len > 0) {
        if (strncmp(ns->prefix, name, len) == 0)
            name += len;
        else {
            i_assert(strcasecmp(name, "INBOX") == 0);
        }
    }
    return mail_namespace_fix_sep(ns, name);
}

const char *mail_namespace_get_vname(struct mail_namespace *ns, string_t *dest,
                     const char *name)
{
    str_truncate(dest, 0);
    if ((ns->flags & NAMESPACE_FLAG_INBOX_USER) == 0 ||
        strcasecmp(name, "INBOX") != 0 ||
        ns->user != ns->owner)
        str_append(dest, ns->prefix);

    for (; *name != '\0'; name++) {
        if (*name == ns->real_sep)
            str_append_c(dest, ns->sep);
        else
            str_append_c(dest, *name);
    }
    return str_c(dest);
}

struct mail_storage *
mail_namespace_get_default_storage(struct mail_namespace *ns)
{
    /* currently we don't support more than one storage per namespace */
    return ns->storage;
}

char mail_namespaces_get_root_sep(const struct mail_namespace *namespaces)
{
    while ((namespaces->flags & NAMESPACE_FLAG_LIST_PREFIX) == 0)
        namespaces = namespaces->next;
    return namespaces->sep;
}

static bool mail_namespace_is_usable_prefix(struct mail_namespace *ns,
                        const char *mailbox, bool inbox)
{
    if (strncmp(ns->prefix, mailbox, ns->prefix_len) == 0) {
        /* true exact prefix match */
        return TRUE;
    }

    if (inbox && strncmp(ns->prefix, "INBOX", 5) == 0 &&
        strncmp(ns->prefix+5, mailbox+5, ns->prefix_len-5) == 0) {
        /* we already checked that mailbox begins with case-insensitive
           INBOX. this namespace also begins with INBOX and the rest
           of the prefix matches too. */
        return TRUE;
    }

    if (strncmp(ns->prefix, mailbox, ns->prefix_len-1) == 0 &&
        mailbox[ns->prefix_len-1] == '\0' &&
        ns->prefix[ns->prefix_len-1] == ns->sep) {
        /* we're trying to access the namespace prefix itself */
        return TRUE;
    }
    return FALSE;
}

static struct mail_namespace *
mail_namespace_find_mask(struct mail_namespace *namespaces,
             const char **mailbox,
             enum namespace_flags flags,
             enum namespace_flags mask)
{
        struct mail_namespace *ns = namespaces;
    const char *box = *mailbox;
    struct mail_namespace *best = NULL;
    unsigned int len, best_len = 0;
    bool inbox;

    inbox = strncasecmp(box, "INBOX", 5) == 0;
    if (inbox && box[5] == '\0') {
        /* find the INBOX namespace */
        *mailbox = "INBOX";
        while (ns != NULL) {
            if ((ns->flags & NAMESPACE_FLAG_INBOX_USER) != 0 &&
                (ns->flags & mask) == flags)
                return ns;
            if (*ns->prefix == '\0')
                best = ns;
            ns = ns->next;
        }
        return best;
    }

    for (; ns != NULL; ns = ns->next) {
        if (ns->prefix_len >= best_len && (ns->flags & mask) == flags &&
            mail_namespace_is_usable_prefix(ns, box, inbox)) {
            best = ns;
            best_len = ns->prefix_len;
        }
    }

    if (best != NULL) {
        if (best_len > 0) {
            len = strlen(*mailbox);
            *mailbox += I_MIN(len, best_len);
        } else if (inbox && (box[5] == best->sep || box[5] == '\0'))
            *mailbox = t_strconcat("INBOX", box+5, NULL);

        *mailbox = mail_namespace_fix_sep(best, *mailbox);
    }
    return best;
}

static struct mail_namespace *
mail_namespace_find_shared(struct mail_namespace *ns, const char **mailbox)
{
    struct mailbox_list *list = ns->list;
    struct mail_storage *storage;

    if (mailbox_list_get_storage(&list, mailbox, &storage) < 0)
        return ns;

    return mailbox_list_get_namespace(list);
}

struct mail_namespace *
mail_namespace_find(struct mail_namespace *namespaces, const char **mailbox)
{
    struct mail_namespace *ns;

    ns = mail_namespace_find_mask(namespaces, mailbox, 0, 0);
    if (ns != NULL && ns->type == NAMESPACE_SHARED &&
        (ns->flags & NAMESPACE_FLAG_AUTOCREATED) == 0) {
        /* see if we need to autocreate a namespace for shared user */
        if (strchr(*mailbox, ns->sep) != NULL)
            return mail_namespace_find_shared(ns, mailbox);
    }
    return ns;
}

struct mail_namespace *
mail_namespace_find_visible(struct mail_namespace *namespaces,
                const char **mailbox)
{
    return mail_namespace_find_mask(namespaces, mailbox, 0,
                    NAMESPACE_FLAG_HIDDEN);
}

struct mail_namespace *
mail_namespace_find_subscribable(struct mail_namespace *namespaces,
                 const char **mailbox)
{
    return mail_namespace_find_mask(namespaces, mailbox,
                    NAMESPACE_FLAG_SUBSCRIPTIONS,
                    NAMESPACE_FLAG_SUBSCRIPTIONS);
}

struct mail_namespace *
mail_namespace_find_unsubscribable(struct mail_namespace *namespaces,
                   const char **mailbox)
{
    return mail_namespace_find_mask(namespaces, mailbox,
                    0, NAMESPACE_FLAG_SUBSCRIPTIONS);
}

struct mail_namespace *
mail_namespace_find_inbox(struct mail_namespace *namespaces)
{
    while ((namespaces->flags & NAMESPACE_FLAG_INBOX_USER) == 0)
        namespaces = namespaces->next;
    return namespaces;
}

bool mail_namespace_update_name(const struct mail_namespace *ns,
                const char **mailbox)
{
    struct mail_namespace tmp_ns = *ns;

    /* FIXME: a bit kludgy.. */
    tmp_ns.next = NULL;
    return mail_namespace_find_mask(&tmp_ns, mailbox, 0, 0) != NULL;
}

struct mail_namespace *
mail_namespace_find_prefix(struct mail_namespace *namespaces,
               const char *prefix)
{
        struct mail_namespace *ns;
    unsigned int len = strlen(prefix);

    for (ns = namespaces; ns != NULL; ns = ns->next) {
        if (ns->prefix_len == len &&
            strcmp(ns->prefix, prefix) == 0)
            return ns;
    }
    return NULL;
}

struct mail_namespace *
mail_namespace_find_prefix_nosep(struct mail_namespace *namespaces,
                 const char *prefix)
{
        struct mail_namespace *ns;
    unsigned int len = strlen(prefix);

    for (ns = namespaces; ns != NULL; ns = ns->next) {
        if (ns->prefix_len == len + 1 &&
            strncmp(ns->prefix, prefix, len) == 0 &&
            ns->prefix[len] == ns->sep)
            return ns;
    }
    return NULL;
}