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  • /*
     * Asterisk -- An open source telephony toolkit.
     *
     * Copyright (C) 2013, Digium, Inc.
     *
     * Richard Mudgett <rmudgett@digium.com>
     *
     * See http://www.asterisk.org for more information about
     * the Asterisk project. Please do not directly contact
     * any of the maintainers of this project for assistance;
     * the project provides a web site, mailing lists and IRC
     * channels for your use.
     *
     * This program is free software, distributed under the terms of
     * the GNU General Public License Version 2. See the LICENSE file
     * at the top of the source tree.
     */
    
    /*!
     * \file
     * \brief Core external MWI support.
     *
     * \details
     * The module manages the persistent message counts cache and supplies
     * an API to allow the protocol specific modules to control the counts
     * or a subset.
     *
     * \author Richard Mudgett <rmudgett@digium.com>
     *
     * See Also:
     * \arg \ref AstCREDITS
     */
    
    /*** MODULEINFO
    	<defaultenabled>no</defaultenabled>
    	<support_level>core</support_level>
     ***/
    
    /*** DOCUMENTATION
    	<configInfo name="res_mwi_external" language="en_US">
    		<synopsis>Core external MWI support</synopsis>
    		<configFile name="sorcery.conf">
    			<configObject name="mailboxes">
    				<synopsis>Persistent cache of external MWI Mailboxs.</synopsis>
    				<description>
    					<para>Allows the alteration of sorcery backend mapping for
    					the persistent cache of external MWI mailboxes.</para>
    				</description>
    			</configObject>
    		</configFile>
    	</configInfo>
     ***/
    
    
    #include "asterisk.h"
    
    #include "asterisk/app.h"
    #include "asterisk/module.h"
    #include "asterisk/res_mwi_external.h"
    #include "asterisk/sorcery.h"
    #include "asterisk/cli.h"
    
    /* ------------------------------------------------------------------- */
    
    /*!
     * Define to include CLI commands to manipulate the external MWI mailboxes.
     * Useful for testing the module functionality.
     */
    //#define MWI_DEBUG_CLI		1
    
    #define MWI_ASTDB_PREFIX	"mwi_external"
    #define MWI_MAILBOX_TYPE	"mailboxes"
    
    struct ast_mwi_mailbox_object {
    	SORCERY_OBJECT(details);
    	/*! Number of new messages in mailbox. */
    	unsigned int msgs_new;
    	/*! Number of old messages in mailbox. */
    	unsigned int msgs_old;
    };
    
    static struct ast_sorcery *mwi_sorcery;
    
    /*!
     * \internal
     * \brief Post an update event to the MWI counts.
     * \since 12.1.0
     *
     * \return Nothing
     */
    static void mwi_post_event(const struct ast_mwi_mailbox_object *mailbox)
    {
    	ast_publish_mwi_state(ast_sorcery_object_get_id(mailbox), NULL,
    		mailbox->msgs_new, mailbox->msgs_old);
    }
    
    static void mwi_observe_update(const void *obj)
    {
    	mwi_post_event(obj);
    }
    
    /*!
     * \internal
     * \brief Post a count clearing event to the MWI counts.
     * \since 12.1.0
     *
     * \return Nothing
     */
    static void mwi_observe_delete(const void *obj)
    {
    	const struct ast_mwi_mailbox_object *mailbox = obj;
    
    
    	if (mailbox->msgs_new || mailbox->msgs_old) {
    		/* Post a count clearing event. */
    		ast_publish_mwi_state(ast_sorcery_object_get_id(mailbox), NULL, 0, 0);
    
    	/* Post a cache remove event. */
    	ast_delete_mwi_state(ast_sorcery_object_get_id(mailbox), NULL);
    
    }
    
    static const struct ast_sorcery_observer mwi_observers = {
    	.created = mwi_observe_update,
    	.updated = mwi_observe_update,
    	.deleted = mwi_observe_delete,
    };
    
    /*! \brief Internal function to allocate a mwi object */
    static void *mwi_sorcery_object_alloc(const char *id)
    {
    	return ast_sorcery_generic_alloc(sizeof(struct ast_mwi_mailbox_object), NULL);
    }
    
    /*!
     * \internal
     * \brief Initialize sorcery for external MWI.
     * \since 12.1.0
     *
     * \retval 0 on success.
     * \retval -1 on error.
     */
    static int mwi_sorcery_init(void)
    {
    	int res;
    
    	mwi_sorcery = ast_sorcery_open();
    	if (!mwi_sorcery) {
    		ast_log(LOG_ERROR, "MWI external: Sorcery failed to open.\n");
    		return -1;
    	}
    
    	/* Map the external MWI wizards. */
    
    	if (ast_sorcery_apply_default(mwi_sorcery, MWI_MAILBOX_TYPE, "astdb",
    			MWI_ASTDB_PREFIX) == AST_SORCERY_APPLY_FAIL) {
    
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    		ast_log(LOG_ERROR, "MWI external: Sorcery could not setup wizards.\n");
    		return -1;
    	}
    
    	res = ast_sorcery_object_register(mwi_sorcery, MWI_MAILBOX_TYPE,
    		mwi_sorcery_object_alloc, NULL, NULL);
    	if (res) {
    		ast_log(LOG_ERROR, "MWI external: Sorcery could not register object type '%s'.\n",
    			MWI_MAILBOX_TYPE);
    		return -1;
    	}
    
    	/* Define the MWI_MAILBOX_TYPE object fields. */
    	res |= ast_sorcery_object_field_register_nodoc(mwi_sorcery, MWI_MAILBOX_TYPE,
    		"msgs_new", "0", OPT_UINT_T, 0, FLDSET(struct ast_mwi_mailbox_object, msgs_new));
    	res |= ast_sorcery_object_field_register_nodoc(mwi_sorcery, MWI_MAILBOX_TYPE,
    		"msgs_old", "0", OPT_UINT_T, 0, FLDSET(struct ast_mwi_mailbox_object, msgs_old));
    	return res ? -1 : 0;
    }
    
    struct ao2_container *ast_mwi_mailbox_get_all(void)
    {
    	return ast_sorcery_retrieve_by_fields(mwi_sorcery, MWI_MAILBOX_TYPE,
    		AST_RETRIEVE_FLAG_MULTIPLE | AST_RETRIEVE_FLAG_ALL, NULL);
    }
    
    struct ao2_container *ast_mwi_mailbox_get_by_regex(const char *regex)
    {
    	return ast_sorcery_retrieve_by_regex(mwi_sorcery, MWI_MAILBOX_TYPE, regex ?: "");
    }
    
    const struct ast_mwi_mailbox_object *ast_mwi_mailbox_get(const char *mailbox_id)
    {
    	if (ast_strlen_zero(mailbox_id)) {
    		return NULL;
    	}
    
    	return ast_sorcery_retrieve_by_id(mwi_sorcery, MWI_MAILBOX_TYPE, mailbox_id);
    }
    
    struct ast_mwi_mailbox_object *ast_mwi_mailbox_alloc(const char *mailbox_id)
    {
    	if (ast_strlen_zero(mailbox_id)) {
    		return NULL;
    	}
    
    	return ast_sorcery_alloc(mwi_sorcery, MWI_MAILBOX_TYPE, mailbox_id);
    }
    
    struct ast_mwi_mailbox_object *ast_mwi_mailbox_copy(const struct ast_mwi_mailbox_object *mailbox)
    {
    	return ast_sorcery_copy(mwi_sorcery, mailbox);
    }
    
    const char *ast_mwi_mailbox_get_id(const struct ast_mwi_mailbox_object *mailbox)
    {
    	return ast_sorcery_object_get_id(mailbox);
    }
    
    unsigned int ast_mwi_mailbox_get_msgs_new(const struct ast_mwi_mailbox_object *mailbox)
    {
    	return mailbox->msgs_new;
    }
    
    unsigned int ast_mwi_mailbox_get_msgs_old(const struct ast_mwi_mailbox_object *mailbox)
    {
    	return mailbox->msgs_old;
    }
    
    void ast_mwi_mailbox_set_msgs_new(struct ast_mwi_mailbox_object *mailbox, unsigned int num_msgs)
    {
    	mailbox->msgs_new = num_msgs;
    }
    
    void ast_mwi_mailbox_set_msgs_old(struct ast_mwi_mailbox_object *mailbox, unsigned int num_msgs)
    {
    	mailbox->msgs_old = num_msgs;
    }
    
    int ast_mwi_mailbox_update(struct ast_mwi_mailbox_object *mailbox)
    {
    	const struct ast_mwi_mailbox_object *exists;
    	int res;
    
    	exists = ast_sorcery_retrieve_by_id(mwi_sorcery, MWI_MAILBOX_TYPE,
    		ast_sorcery_object_get_id(mailbox));
    	if (exists) {
    		res = ast_sorcery_update(mwi_sorcery, mailbox);
    		ast_mwi_mailbox_unref(exists);
    	} else {
    		res = ast_sorcery_create(mwi_sorcery, mailbox);
    	}
    	return res;
    }
    
    /*!
     * \internal
     * \brief Delete a mailbox.
     * \since 12.1.0
     *
     * \param mailbox Mailbox object to delete from sorcery.
     *
     * \return Nothing
     */
    static void mwi_mailbox_delete(struct ast_mwi_mailbox_object *mailbox)
    {
    	ast_sorcery_delete(mwi_sorcery, mailbox);
    }
    
    /*!
     * \internal
     * \brief Delete all mailboxes in container.
     * \since 12.1.0
     *
     * \param mailboxes Mailbox objects to delete from sorcery.
     *
     * \return Nothing
     */
    static void mwi_mailbox_delete_all(struct ao2_container *mailboxes)
    {
    	struct ast_mwi_mailbox_object *mailbox;
    	struct ao2_iterator iter;
    
    	iter = ao2_iterator_init(mailboxes, AO2_ITERATOR_UNLINK);
    	for (; (mailbox = ao2_iterator_next(&iter)); ast_mwi_mailbox_unref(mailbox)) {
    		mwi_mailbox_delete(mailbox);
    	}
    	ao2_iterator_destroy(&iter);
    }
    
    int ast_mwi_mailbox_delete_all(void)
    {
    	struct ao2_container *mailboxes;
    
    	mailboxes = ast_mwi_mailbox_get_all();
    	if (mailboxes) {
    		mwi_mailbox_delete_all(mailboxes);
    		ao2_ref(mailboxes, -1);
    	}
    	return 0;
    }
    
    int ast_mwi_mailbox_delete_by_regex(const char *regex)
    {
    	struct ao2_container *mailboxes;
    
    	mailboxes = ast_mwi_mailbox_get_by_regex(regex);
    	if (mailboxes) {
    		mwi_mailbox_delete_all(mailboxes);
    		ao2_ref(mailboxes, -1);
    	}
    	return 0;
    }
    
    int ast_mwi_mailbox_delete(const char *mailbox_id)
    {
    	const struct ast_mwi_mailbox_object *mailbox;
    
    	if (ast_strlen_zero(mailbox_id)) {
    		return -1;
    	}
    
    	mailbox = ast_mwi_mailbox_get(mailbox_id);
    	if (mailbox) {
    		mwi_mailbox_delete((struct ast_mwi_mailbox_object *) mailbox);
    		ast_mwi_mailbox_unref(mailbox);
    	}
    	return 0;
    }
    
    enum folder_map {
    	FOLDER_INVALID = 0,
    	FOLDER_INBOX = 1,
    	FOLDER_OLD = 2,
    };
    
    /*!
     * \internal
     * \brief Determine if the requested folder is valid for external MWI support.
     * \since 12.1.0
     *
     * \param folder Folder name to check (NULL is valid).
     *
     * \return Enum of the supported folder.
     */
    static enum folder_map mwi_folder_map(const char *folder)
    {
    	enum folder_map which_folder;
    
    	if (ast_strlen_zero(folder) || !strcasecmp(folder, "INBOX")) {
    		which_folder = FOLDER_INBOX;
    	} else if (!strcasecmp(folder, "Old")) {
    		which_folder = FOLDER_OLD;
    	} else {
    		which_folder = FOLDER_INVALID;
    	}
    	return which_folder;
    }
    
    /*!
     * \internal
     * \brief Gets the number of messages that exist in a mailbox folder.
     * \since 12.1.0
     *
     * \param mailbox_id The mailbox name.
     * \param folder The folder to look in.  Default is INBOX if not provided.
     *
     * \return The number of messages in the mailbox folder (zero or more).
     */
    static int mwi_messagecount(const char *mailbox_id, const char *folder)
    {
    	const struct ast_mwi_mailbox_object *mailbox;
    	int num_msgs;
    	enum folder_map which_folder;
    
    	which_folder = mwi_folder_map(folder);
    	if (which_folder == FOLDER_INVALID) {
    		return 0;
    	}
    
    	mailbox = ast_mwi_mailbox_get(mailbox_id);
    	if (!mailbox) {
    		return 0;
    	}
    	num_msgs = 0;
    	switch (which_folder) {
    	case FOLDER_INVALID:
    		break;
    	case FOLDER_INBOX:
    		num_msgs = mailbox->msgs_new;
    		break;
    	case FOLDER_OLD:
    		num_msgs = mailbox->msgs_old;
    		break;
    	}
    	ast_mwi_mailbox_unref(mailbox);
    
    	return num_msgs;
    }
    
    /*!
     * \internal
     * \brief Determines if the given folder has messages.
     * \since 12.1.0
     *
     * \param mailboxes Comma or & delimited list of mailboxes.
     * \param folder The folder to look in.  Default is INBOX if not provided.
     *
     * \retval 1 if the folder has one or more messages.
     * \retval 0 otherwise.
     */
    static int mwi_has_voicemail(const char *mailboxes, const char *folder)
    {
    	char *parse;
    	char *mailbox_id;
    	enum folder_map which_folder;
    
    	which_folder = mwi_folder_map(folder);
    	if (which_folder == FOLDER_INVALID) {
    		return 0;
    	}
    
    	/* For each mailbox in the list. */
    	parse = ast_strdupa(mailboxes);
    	while ((mailbox_id = strsep(&parse, ",&"))) {
    		const struct ast_mwi_mailbox_object *mailbox;
    		int num_msgs;
    
    		/* Get the specified mailbox. */
    		mailbox = ast_mwi_mailbox_get(mailbox_id);
    		if (!mailbox) {
    			continue;
    		}
    
    		/* Done if the found mailbox has any messages. */
    		num_msgs = 0;
    		switch (which_folder) {
    		case FOLDER_INVALID:
    			break;
    		case FOLDER_INBOX:
    			num_msgs = mailbox->msgs_new;
    			break;
    		case FOLDER_OLD:
    			num_msgs = mailbox->msgs_old;
    			break;
    		}
    		ast_mwi_mailbox_unref(mailbox);
    		if (num_msgs) {
    			return 1;
    		}
    	}
    
    	return 0;
    }
    
    /*!
     * \internal
     * \brief Gets the number of messages that exist for the mailbox list.
     * \since 12.1.0
     *
     * \param mailboxes Comma or space delimited list of mailboxes.
     * \param newmsgs Where to put the count of new messages. (Can be NULL)
     * \param oldmsgs Where to put the count of old messages. (Can be NULL)
     *
     * \details
     * Simultaneously determines the count of new and old
     * messages.  The total messages would then be the sum of these.
     *
     * \retval 0 on success
     * \retval -1 on failure
     */
    static int mwi_inboxcount(const char *mailboxes, int *newmsgs, int *oldmsgs)
    {
    	char *parse;
    	char *mailbox_id;
    
    	if (!newmsgs && !oldmsgs) {
    		/* Nowhere to accumulate counts */
    		return 0;
    	}
    
    	/* For each mailbox in the list. */
    	parse = ast_strdupa(mailboxes);
    	while ((mailbox_id = strsep(&parse, ", "))) {
    		const struct ast_mwi_mailbox_object *mailbox;
    
    		/* Get the specified mailbox. */
    		mailbox = ast_mwi_mailbox_get(mailbox_id);
    		if (!mailbox) {
    			continue;
    		}
    
    		/* Accumulate the counts. */
    		if (newmsgs) {
    			*newmsgs += mailbox->msgs_new;
    		}
    		if (oldmsgs) {
    			*oldmsgs += mailbox->msgs_old;
    		}
    
    		ast_mwi_mailbox_unref(mailbox);
    	}
    
    	return 0;
    }
    
    /*!
     * \internal
     * \brief Gets the number of messages that exist for the mailbox list.
     * \since 12.1.0
     *
     * \param mailboxes Comma or space delimited list of mailboxes.
     * \param urgentmsgs Where to put the count of urgent messages. (Can be NULL)
     * \param newmsgs Where to put the count of new messages. (Can be NULL)
     * \param oldmsgs Where to put the count of old messages. (Can be NULL)
     *
     * \details
     * Simultaneously determines the count of new, old, and urgent
     * messages.  The total messages would then be the sum of these
     * three.
     *
     * \retval 0 on success
     * \retval -1 on failure
     */
    static int mwi_inboxcount2(const char *mailboxes, int *urgentmsgs, int *newmsgs, int *oldmsgs)
    {
    	/*
    	 * This module does not support urgentmsgs.  Just ignore them.
    	 * The global API call has already set the count to zero.
    	 */
    	return mwi_inboxcount(mailboxes, newmsgs, oldmsgs);
    }
    
    static const struct ast_vm_functions vm_table = {
    	.module_version = VM_MODULE_VERSION,
    	.module_name = AST_MODULE,
    
    	.has_voicemail = mwi_has_voicemail,
    	.inboxcount = mwi_inboxcount,
    	.inboxcount2 = mwi_inboxcount2,
    	.messagecount = mwi_messagecount,
    };
    
    #if defined(MWI_DEBUG_CLI)
    static char *complete_mailbox(const char *word, int state)
    {
    	struct ao2_iterator iter;
    	int wordlen = strlen(word);
    	int which = 0;
    	char *ret = NULL;
    	char *regex;
    	const struct ast_mwi_mailbox_object *mailbox;
    	RAII_VAR(struct ao2_container *, mailboxes, NULL, ao2_cleanup);
    
    	regex = ast_alloca(2 + wordlen);
    	sprintf(regex, "^%s", word);/* Safe */
    
    	mailboxes = ast_mwi_mailbox_get_by_regex(regex);
    	if (!mailboxes) {
    		return NULL;
    	}
    
    	iter = ao2_iterator_init(mailboxes, 0);
    	for (; (mailbox = ao2_iterator_next(&iter)); ast_mwi_mailbox_unref(mailbox)) {
    		if (++which > state) {
    			ret = ast_strdup(ast_sorcery_object_get_id(mailbox));
    			ast_mwi_mailbox_unref(mailbox);
    			break;
    		}
    	}
    	ao2_iterator_destroy(&iter);
    
    	return ret;
    }
    #endif	/* defined(MWI_DEBUG_CLI) */
    
    #if defined(MWI_DEBUG_CLI)
    static char *handle_mwi_delete_all(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
    {
    	switch (cmd) {
    	case CLI_INIT:
    		e->command = "mwi delete all";
    		e->usage =
    			"Usage: mwi delete all\n"
    			"       Delete all external MWI mailboxes.\n";
    		return NULL;
    	case CLI_GENERATE:
    		return NULL;
    	}
    
    	ast_mwi_mailbox_delete_all();
    	ast_cli(a->fd, "Deleted all external MWI mailboxes.\n");
    	return CLI_SUCCESS;
    }
    #endif	/* defined(MWI_DEBUG_CLI) */
    
    #if defined(MWI_DEBUG_CLI)
    static char *handle_mwi_delete_like(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
    {
    	const char *regex;
    
    	switch (cmd) {
    	case CLI_INIT:
    		e->command = "mwi delete like";
    		e->usage =
    			"Usage: mwi delete like <pattern>\n"
    			"       Delete external MWI mailboxes matching a regular expression.\n";
    		return NULL;
    	case CLI_GENERATE:
    		return NULL;
    	}
    
    	if (a->argc != 4) {
    		return CLI_SHOWUSAGE;
    	}
    	regex = a->argv[3];
    
    	ast_mwi_mailbox_delete_by_regex(regex);
    	ast_cli(a->fd, "Deleted external MWI mailboxes matching '%s'.\n", regex);
    	return CLI_SUCCESS;
    }
    #endif	/* defined(MWI_DEBUG_CLI) */
    
    #if defined(MWI_DEBUG_CLI)
    static char *handle_mwi_delete_mailbox(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
    {
    	const char *mailbox_id;
    
    	switch (cmd) {
    	case CLI_INIT:
    		e->command = "mwi delete mailbox";
    		e->usage =
    			"Usage: mwi delete mailbox <mailbox_id>\n"
    			"       Delete a specific external MWI mailbox.\n";
    		return NULL;
    	case CLI_GENERATE:
    		if (a->pos == 3) {
    			return complete_mailbox(a->word, a->n);
    		}
    		return NULL;
    	}
    
    	if (a->argc != 4) {
    		return CLI_SHOWUSAGE;
    	}
    	mailbox_id = a->argv[3];
    
    	ast_mwi_mailbox_delete(mailbox_id);
    	ast_cli(a->fd, "Deleted external MWI mailbox '%s'.\n", mailbox_id);
    
    	return CLI_SUCCESS;
    }
    #endif	/* defined(MWI_DEBUG_CLI) */
    
    #define FORMAT_MAILBOX_HDR "%6s %6s %s\n"
    #define FORMAT_MAILBOX_ROW "%6u %6u %s\n"
    
    #if defined(MWI_DEBUG_CLI)
    /*!
     * \internal
     * \brief Print a mailbox list line to CLI.
     * \since 12.1.0
     *
     * \param cli_fd File descriptor for CLI output.
     * \param mailbox What to list.
     *
     * \return Nothing
     */
    static void mwi_cli_print_mailbox(int cli_fd, const struct ast_mwi_mailbox_object *mailbox)
    {
    	ast_cli(cli_fd, FORMAT_MAILBOX_ROW, mailbox->msgs_new, mailbox->msgs_old,
    		ast_sorcery_object_get_id(mailbox));
    }
    #endif	/* defined(MWI_DEBUG_CLI) */
    
    #if defined(MWI_DEBUG_CLI)
    /*!
     * \internal
     * \brief List all mailboxes in the given container.
     * \since 12.1.0
     *
     * \param cli_fd File descriptor for CLI output.
     * \param mailboxes What to list.
     *
     * \return Nothing
     */
    static void mwi_cli_list_mailboxes(int cli_fd, struct ao2_container *mailboxes)
    {
    	struct ao2_iterator iter;
    	const struct ast_mwi_mailbox_object *mailbox;
    
    	ast_cli(cli_fd, FORMAT_MAILBOX_HDR, "New", "Old", "Mailbox");
    
    	iter = ao2_iterator_init(mailboxes, 0);
    	for (; (mailbox = ao2_iterator_next(&iter)); ast_mwi_mailbox_unref(mailbox)) {
    		mwi_cli_print_mailbox(cli_fd, mailbox);
    	}
    	ao2_iterator_destroy(&iter);
    }
    #endif	/* defined(MWI_DEBUG_CLI) */
    
    #undef FORMAT_MAILBOX_HDR
    #undef FORMAT_MAILBOX_ROW
    
    #if defined(MWI_DEBUG_CLI)
    static char *handle_mwi_list_all(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
    {
    	struct ao2_container *mailboxes;
    
    	switch (cmd) {
    	case CLI_INIT:
    		e->command = "mwi list all";
    		e->usage =
    			"Usage: mwi list all\n"
    			"       List all external MWI mailboxes.\n";
    		return NULL;
    	case CLI_GENERATE:
    		return NULL;
    	}
    
    	mailboxes = ast_mwi_mailbox_get_all();
    	if (!mailboxes) {
    		ast_cli(a->fd, "Failed to retrieve external MWI mailboxes.\n");
    		return CLI_SUCCESS;
    	}
    	mwi_cli_list_mailboxes(a->fd, mailboxes);
    	ao2_ref(mailboxes, -1);
    	return CLI_SUCCESS;
    }
    #endif	/* defined(MWI_DEBUG_CLI) */
    
    #if defined(MWI_DEBUG_CLI)
    static char *handle_mwi_list_like(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
    {
    	struct ao2_container *mailboxes;
    	const char *regex;
    
    	switch (cmd) {
    	case CLI_INIT:
    		e->command = "mwi list like";
    		e->usage =
    			"Usage: mwi list like <pattern>\n"
    			"       List external MWI mailboxes matching a regular expression.\n";
    		return NULL;
    	case CLI_GENERATE:
    		return NULL;
    	}
    
    	if (a->argc != 4) {
    		return CLI_SHOWUSAGE;
    	}
    	regex = a->argv[3];
    
    	mailboxes = ast_mwi_mailbox_get_by_regex(regex);
    	if (!mailboxes) {
    		ast_cli(a->fd, "Failed to retrieve external MWI mailboxes.\n");
    		return CLI_SUCCESS;
    	}
    	mwi_cli_list_mailboxes(a->fd, mailboxes);
    	ao2_ref(mailboxes, -1);
    	return CLI_SUCCESS;
    }
    #endif	/* defined(MWI_DEBUG_CLI) */
    
    #if defined(MWI_DEBUG_CLI)
    static char *handle_mwi_show_mailbox(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
    {
    	const struct ast_mwi_mailbox_object *mailbox;
    	const char *mailbox_id;
    
    	switch (cmd) {
    	case CLI_INIT:
    		e->command = "mwi show mailbox";
    		e->usage =
    			"Usage: mwi show mailbox <mailbox_id>\n"
    			"       Show a specific external MWI mailbox.\n";
    		return NULL;
    	case CLI_GENERATE:
    		if (a->pos == 3) {
    			return complete_mailbox(a->word, a->n);
    		}
    		return NULL;
    	}
    
    	if (a->argc != 4) {
    		return CLI_SHOWUSAGE;
    	}
    	mailbox_id = a->argv[3];
    
    	mailbox = ast_mwi_mailbox_get(mailbox_id);
    	if (mailbox) {
    		ast_cli(a->fd,
    			"Mailbox: %s\n"
    			"NewMessages: %u\n"
    			"OldMessages: %u\n",
    			ast_sorcery_object_get_id(mailbox),
    			mailbox->msgs_new,
    			mailbox->msgs_old);
    
    		ast_mwi_mailbox_unref(mailbox);
    	} else {
    		ast_cli(a->fd, "External MWI mailbox '%s' not found.\n", mailbox_id);
    	}
    
    	return CLI_SUCCESS;
    }
    #endif	/* defined(MWI_DEBUG_CLI) */
    
    #if defined(MWI_DEBUG_CLI)
    static char *handle_mwi_update_mailbox(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
    {
    	struct ast_mwi_mailbox_object *mailbox;
    	const char *mailbox_id;
    	unsigned int num_new;
    	unsigned int num_old;
    
    	switch (cmd) {
    	case CLI_INIT:
    		e->command = "mwi update mailbox";
    		e->usage =
    			"Usage: mwi update mailbox <mailbox_id> [<new> [<old>]]\n"
    			"       Update a specific external MWI mailbox.\n";
    		return NULL;
    	case CLI_GENERATE:
    		if (a->pos == 3) {
    			return complete_mailbox(a->word, a->n);
    		}
    		return NULL;
    	}
    
    	if (a->argc < 4 || 6 < a->argc) {
    		return CLI_SHOWUSAGE;
    	}
    	mailbox_id = a->argv[3];
    
    	num_new = 0;
    	if (4 < a->argc) {
    		const char *count_new = a->argv[4];
    
    		if (sscanf(count_new, "%u", &num_new) != 1) {
    			ast_cli(a->fd, "Invalid NewMessages: '%s'.\n", count_new);
    			return CLI_SHOWUSAGE;
    		}
    	}
    
    	num_old = 0;
    	if (5 < a->argc) {
    		const char *count_old = a->argv[5];
    
    		if (sscanf(count_old, "%u", &num_old) != 1) {
    			ast_cli(a->fd, "Invalid OldMessages: '%s'.\n", count_old);
    			return CLI_SHOWUSAGE;
    		}
    	}
    
    	mailbox = ast_mwi_mailbox_alloc(mailbox_id);
    	if (mailbox) {
    		ast_mwi_mailbox_set_msgs_new(mailbox, num_new);
    		ast_mwi_mailbox_set_msgs_old(mailbox, num_old);
    		if (ast_mwi_mailbox_update(mailbox)) {
    			ast_cli(a->fd, "Could not update mailbox %s.\n",
    				ast_sorcery_object_get_id(mailbox));
    		} else {
    			ast_cli(a->fd, "Updated mailbox %s.\n", ast_sorcery_object_get_id(mailbox));
    		}
    
    		ast_mwi_mailbox_unref(mailbox);
    	}
    
    	return CLI_SUCCESS;
    }
    #endif	/* defined(MWI_DEBUG_CLI) */
    
    #if defined(MWI_DEBUG_CLI)
    static struct ast_cli_entry mwi_cli[] = {
    	AST_CLI_DEFINE(handle_mwi_delete_all, "Delete all external MWI mailboxes"),
    	AST_CLI_DEFINE(handle_mwi_delete_like, "Delete external MWI mailboxes matching regex"),
    	AST_CLI_DEFINE(handle_mwi_delete_mailbox, "Delete a specific external MWI mailbox"),
    	AST_CLI_DEFINE(handle_mwi_list_all, "List all external MWI mailboxes"),
    	AST_CLI_DEFINE(handle_mwi_list_like, "List external MWI mailboxes matching regex"),
    	AST_CLI_DEFINE(handle_mwi_show_mailbox, "Show a specific external MWI mailbox"),
    	AST_CLI_DEFINE(handle_mwi_update_mailbox, "Update a specific external MWI mailbox"),
    };
    #endif	/* defined(MWI_DEBUG_CLI) */
    
    /*!
     * \internal
     * \brief Post initial MWI count events.
     * \since 12.1.0
     *
     * \return Nothing
     */
    static void mwi_initial_events(void)
    {
    	struct ao2_container *mailboxes;
    	const struct ast_mwi_mailbox_object *mailbox;
    	struct ao2_iterator iter;
    
    	/* Get all mailbox counts. */
    	mailboxes = ast_mwi_mailbox_get_all();
    	if (!mailboxes) {
    		return;
    	}
    
    	/* Post all mailbox counts. */
    	iter = ao2_iterator_init(mailboxes, AO2_ITERATOR_UNLINK);
    	for (; (mailbox = ao2_iterator_next(&iter)); ast_mwi_mailbox_unref(mailbox)) {
    		mwi_post_event(mailbox);
    	}
    	ao2_iterator_destroy(&iter);
    
    	ao2_ref(mailboxes, -1);
    }
    
    static int unload_module(void)
    {
    	ast_vm_unregister(vm_table.module_name);
    #if defined(MWI_DEBUG_CLI)
    	ast_cli_unregister_multiple(mwi_cli, ARRAY_LEN(mwi_cli));
    #endif	/* defined(MWI_DEBUG_CLI) */
    	ast_sorcery_observer_remove(mwi_sorcery, MWI_MAILBOX_TYPE, &mwi_observers);
    
    	ast_sorcery_unref(mwi_sorcery);
    	mwi_sorcery = NULL;
    
    	return 0;
    }
    
    static int load_module(void)
    {
    
    	if (mwi_sorcery_init()
    		|| ast_sorcery_observer_add(mwi_sorcery, MWI_MAILBOX_TYPE, &mwi_observers)
    #if defined(MWI_DEBUG_CLI)
    		|| ast_cli_register_multiple(mwi_cli, ARRAY_LEN(mwi_cli))
    #endif	/* defined(MWI_DEBUG_CLI) */
    
    		) {
    		unload_module();
    		return AST_MODULE_LOAD_DECLINE;
    	}
    
    	/* ast_vm_register may return DECLINE if another module registered for vm */
    	res = ast_vm_register(&vm_table);
    	if (res) {
    		ast_log(LOG_ERROR, "Failure registering as a voicemail provider\n");
    
    		unload_module();
    		return AST_MODULE_LOAD_DECLINE;
    	}
    
    	/* Post initial MWI count events. */
    	mwi_initial_events();
    
    	return AST_MODULE_LOAD_SUCCESS;
    }
    
    AST_MODULE_INFO(ASTERISK_GPL_KEY, AST_MODFLAG_GLOBAL_SYMBOLS | AST_MODFLAG_LOAD_ORDER, "Core external MWI resource",
    
    	.load = load_module,
    	.unload = unload_module,
    	.load_pri = AST_MODPRI_CHANNEL_DEPEND - 5,
    );