index/shared/shared-storage.c

	shared-storage.c revision 5f5870385cff47efd2f58e7892f251cf13761528
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster/* Copyright (c) 2008-2012 Dovecot authors, see the included COPYING file */
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster#include "lib.h"
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster#include "array.h"
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster#include "str.h"
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster#include "ioloop.h"
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster#include "var-expand.h"
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster#include "index-storage.h"
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster#include "mailbox-list-private.h"
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster#include "fail-mail-storage.h"
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster#include "shared-storage.h"
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster#include <stdlib.h>
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster#include <ctype.h>
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Fosterextern struct mail_storage shared_storage;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Fosterstatic struct mail_storage *shared_storage_alloc(void)
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster{
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    struct shared_storage *storage;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    pool_t pool;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    pool = pool_alloconly_create("shared storage", 1024);
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    storage = p_new(pool, struct shared_storage, 1);
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    storage->storage = shared_storage;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    storage->storage.pool = pool;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    return &storage->storage;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster}
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Fosterstatic int
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Fostershared_storage_create(struct mail_storage *_storage, struct mail_namespace *ns,
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster              const char **error_r)
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster{
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    struct shared_storage *storage = (struct shared_storage *)_storage;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    struct mail_storage *storage_class;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    const char *driver, *p;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    char *wildcardp, key;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    bool have_username;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    /* location must begin with the actual mailbox driver */
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    p = strchr(ns->set->location, ':');
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    if (p == NULL) {
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        *error_r = "Shared mailbox location not prefixed with driver";
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        return -1;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    }
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    driver = t_strdup_until(ns->set->location, p);
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    storage->location = p_strdup(_storage->pool, ns->set->location);
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    storage->unexpanded_location =
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        p_strdup(_storage->pool, ns->unexpanded_set->location);
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    storage->storage_class_name = p_strdup(_storage->pool, driver);
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    storage_class = mail_storage_find_class(driver);
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    if (storage_class != NULL)
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        _storage->class_flags = storage_class->class_flags;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    else if (strcmp(driver, "auto") != 0) {
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        *error_r = t_strconcat("Unknown shared storage driver: ",
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster                       driver, NULL);
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        return -1;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    }
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    wildcardp = strchr(ns->prefix, '%');
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    if (wildcardp == NULL) {
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        *error_r = "Shared namespace prefix doesn't contain %";
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        return -1;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    }
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    storage->ns_prefix_pattern = p_strdup(_storage->pool, wildcardp);
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    have_username = FALSE;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    for (p = storage->ns_prefix_pattern; *p != '\0'; p++) {
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        if (*p != '%')
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster            continue;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        key = p[1];
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        if (key == 'u' || key == 'n')
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster            have_username = TRUE;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        else if (key != '%' && key != 'd')
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster            break;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    }
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    if (*p != '\0') {
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        *error_r = "Shared namespace prefix contains unknown variables";
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        return -1;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    }
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    if (!have_username) {
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        *error_r = "Shared namespace prefix doesn't contain %u or %n";
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        return -1;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    }
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    if (p[-1] != mail_namespace_get_sep(ns) &&
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        (ns->flags & (NAMESPACE_FLAG_LIST_PREFIX |
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster              NAMESPACE_FLAG_LIST_CHILDREN)) != 0) {
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        *error_r = "Shared namespace prefix doesn't end with hierarchy separator";
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        return -1;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    }
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    /* truncate prefix after the above checks are done, so they can log
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster       the full prefix in error conditions */
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    *wildcardp = '\0';
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    ns->prefix_len = strlen(ns->prefix);
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    return 0;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster}
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Fosterstatic void
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Fostershared_storage_get_list_settings(const struct mail_namespace *ns ATTR_UNUSED,
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster                 struct mailbox_list_settings *set)
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster{
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    set->layout = "shared";
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster}
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Fosterstatic void
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Fosterget_nonexistent_user_location(struct shared_storage *storage,
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster                  const char *username, string_t *location)
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster{
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    /* user wasn't found. we'll still need to create the storage
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster       to avoid exposing which users exist and which don't. */
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    str_append(location, storage->storage_class_name);
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    str_append_c(location, ':');
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    /* use a reachable but nonexistent path as the mail root directory */
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    str_append(location, storage->storage.user->set->base_dir);
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    str_append(location, "/user-not-found/");
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    str_append(location, username);
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster}
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Fosterint shared_storage_get_namespace(struct mail_namespace **_ns,
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster                 const char **_name)
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster{
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    struct mail_storage *_storage = (*_ns)->storage;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    struct mailbox_list *list = (*_ns)->list;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    struct shared_storage *storage = (struct shared_storage *)_storage;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    struct mail_user *user = _storage->user;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    static struct var_expand_table static_tab[] = {
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        { 'u', NULL, "user" },
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        { 'n', NULL, "username" },
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        { 'd', NULL, "domain" },
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        { 'h', NULL, "home" },
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        { '\0', NULL, NULL }
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    };
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    struct var_expand_table *tab;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    struct mail_namespace *new_ns, *ns = *_ns;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    struct mail_namespace_settings *ns_set, *unexpanded_ns_set;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    struct mail_user *owner;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    const char *domain = NULL, *username = NULL, *userdomain = NULL;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    const char *name, *p, *next, **dest, *error;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    string_t *prefix, *location;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    char ns_sep = mail_namespace_get_sep(ns);
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    int ret;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    p = storage->ns_prefix_pattern;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    for (name = *_name; *p != '\0';) {
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        if (*p != '%') {
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster            if (*p != *name)
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster                break;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster            p++; name++;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster            continue;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        }
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        switch (*++p) {
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        case 'd':
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster            dest = &domain;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster            break;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        case 'n':
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster            dest = &username;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster            break;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        case 'u':
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster            dest = &userdomain;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster            break;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        default:
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster            /* we checked this already above */
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster            i_unreached();
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        }
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        p++;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        next = strchr(name, *p != '\0' ? *p : ns_sep);
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        if (next == NULL) {
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster            *dest = name;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster            name = "";
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster            break;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        }
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        *dest = t_strdup_until(name, next);
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        name = next;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    }
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    if (*p != '\0') {
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        if (*name == '\0' ||
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster            (name[1] == '\0' && *name == ns_sep)) {
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster            /* trying to open <prefix>/<user> mailbox */
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster            name = "INBOX";
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        } else {
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster            mailbox_list_set_critical(list,
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster                    "Invalid namespace prefix %s vs %s",
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster                    storage->ns_prefix_pattern, *_name);
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster            return -1;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        }
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    }
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    /* successfully matched the name. */
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    if (userdomain != NULL) {
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        /* user@domain given */
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        domain = strchr(userdomain, '@');
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        if (domain == NULL)
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster            username = userdomain;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        else {
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster            username = t_strdup_until(userdomain, domain);
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster            domain++;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        }
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    } else if (username == NULL) {
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        /* trying to open namespace "shared/domain"
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster           namespace prefix. */
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        mailbox_list_set_error(list, MAIL_ERROR_NOTFOUND,
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster                       T_MAIL_ERR_MAILBOX_NOT_FOUND(*_name));
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        return -1;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    } else {
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        if (domain == NULL) {
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster            /* no domain given, use ours (if we have one) */
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster            domain = strchr(user->username, '@');
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster            if (domain != NULL) domain++;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        }
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        userdomain = domain == NULL ? username :
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster            t_strconcat(username, "@", domain, NULL);
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    }
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    if (*userdomain == '\0') {
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        mailbox_list_set_error(list, MAIL_ERROR_PARAMS,
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster                       "Empty username doesn't exist");
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster        return -1;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    }
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    /* expand the namespace prefix and see if it already exists.
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster       this should normally happen only when the mailbox is being opened */
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    tab = t_malloc(sizeof(static_tab));
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    memcpy(tab, static_tab, sizeof(static_tab));
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    tab[0].value = userdomain;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    tab[1].value = username;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    tab[2].value = domain;
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    prefix = t_str_new(128);
a688bcbb4bcff5398fdd29b86f83450257dc0df4Allan Foster    str_append(prefix, ns->prefix);
    var_expand(prefix, storage->ns_prefix_pattern, tab);

    *_ns = mail_namespace_find_prefix(user->namespaces, str_c(prefix));
    if (*_ns != NULL) {
        *_name = mailbox_list_get_storage_name(ns->list,
                t_strconcat(ns->prefix, name, NULL));
        return 0;
    }

    owner = mail_user_alloc(userdomain, user->set_info,
                user->unexpanded_set);
    owner->autocreated = TRUE;
    if (!var_has_key(storage->location, 'h', "home"))
        ret = 1;
    else {
        /* we'll need to look up the user's home directory */
        if ((ret = mail_user_get_home(owner, &tab[3].value)) < 0) {
            mailbox_list_set_critical(list, "Namespace '%s': "
                "Could not lookup home for user %s",
                ns->prefix, userdomain);
            mail_user_unref(&owner);
            return -1;
        }
    }
    if (mail_user_init(owner, &error) < 0) {
        mailbox_list_set_critical(list,
            "Couldn't create namespace '%s' for user %s: %s",
            ns->prefix, userdomain, error);
        mail_user_unref(&owner);
        return -1;
    }

    /* create the new namespace */
    new_ns = i_new(struct mail_namespace, 1);
    new_ns->refcount = 1;
    new_ns->type = NAMESPACE_SHARED;
    new_ns->user = user;
    new_ns->prefix = i_strdup(str_c(prefix));
    new_ns->owner = owner;
    new_ns->flags = (NAMESPACE_FLAG_SUBSCRIPTIONS & ns->flags) |
        NAMESPACE_FLAG_LIST_PREFIX | NAMESPACE_FLAG_HIDDEN |
        NAMESPACE_FLAG_AUTOCREATED | NAMESPACE_FLAG_INBOX_ANY;
    new_ns->mail_set = _storage->set;

    location = t_str_new(256);
    if (ret > 0)
        var_expand(location, storage->location, tab);
    else {
        get_nonexistent_user_location(storage, userdomain, location);
        new_ns->flags |= NAMESPACE_FLAG_UNUSABLE;
        if (ns->user->mail_debug) {
            i_debug("shared: Tried to access mails of "
                "nonexistent user %s", userdomain);
        }
    }

    ns_set = p_new(user->pool, struct mail_namespace_settings, 1);
    ns_set->type = "shared";
    ns_set->separator = p_strdup_printf(user->pool, "%c", ns_sep);
    ns_set->prefix = new_ns->prefix;
    ns_set->location = p_strdup(user->pool, str_c(location));
    ns_set->hidden = TRUE;
    ns_set->list = "yes";
    new_ns->set = ns_set;

    unexpanded_ns_set =
        p_new(user->pool, struct mail_namespace_settings, 1);
    *unexpanded_ns_set = *ns_set;
    unexpanded_ns_set->location =
        p_strdup(user->pool, storage->unexpanded_location);
    new_ns->unexpanded_set = unexpanded_ns_set;

    if (mail_storage_create(new_ns, NULL, _storage->flags |
                MAIL_STORAGE_FLAG_NO_AUTOVERIFY, &error) < 0) {
        mailbox_list_set_critical(list, "Namespace '%s': %s",
                      new_ns->prefix, error);
        mail_namespace_destroy(new_ns);
        return -1;
    }
    ns->flags |= NAMESPACE_FLAG_USABLE;
    *_name = mailbox_list_get_storage_name(new_ns->list,
                t_strconcat(new_ns->prefix, name, NULL));
    *_ns = new_ns;
    if (_storage->class_flags == 0) {
        /* flags are unset if we were using "auto" storage */
        _storage->class_flags = new_ns->storage->class_flags;
    }

    mail_user_add_namespace(user, &new_ns);
    return 0;
}

struct mail_storage shared_storage = {
    .name = SHARED_STORAGE_NAME,
    .class_flags = 0, /* unknown at this point */

    .v = {
        NULL,
        shared_storage_alloc,
        shared_storage_create,
        NULL,
        NULL,
        shared_storage_get_list_settings,
        NULL,
        fail_mailbox_alloc,
        NULL
    }
};