asterisk/main/stasis_message.c

255 lines
5.9 KiB
C

/*
* Asterisk -- An open source telephony toolkit.
*
* Copyright (C) 2013, Digium, Inc.
*
* David M. Lee, II <dlee@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 Stasis Message API.
*
* \author David M. Lee, II <dlee@digium.com>
*/
/*** MODULEINFO
<support_level>core</support_level>
***/
#include "asterisk.h"
#include "asterisk/astobj2.h"
#include "asterisk/stasis.h"
#include "asterisk/utils.h"
#include "asterisk/hashtab.h"
/*! \internal */
struct stasis_message_type {
struct stasis_message_vtable *vtable;
char *name;
unsigned int hash;
int id;
enum stasis_subscription_message_formatters available_formatters;
};
static struct stasis_message_vtable null_vtable = {};
static int message_type_id;
static void message_type_dtor(void *obj)
{
struct stasis_message_type *type = obj;
ast_free(type->name);
type->name = NULL;
}
int stasis_message_type_create(const char *name,
struct stasis_message_vtable *vtable,
struct stasis_message_type **result)
{
struct stasis_message_type *type;
/* Check for declination */
if (name && stasis_message_type_declined(name)) {
return STASIS_MESSAGE_TYPE_DECLINED;
}
type = ao2_t_alloc_options(sizeof(*type), message_type_dtor,
AO2_ALLOC_OPT_LOCK_NOLOCK, name ?: "");
if (!type) {
return STASIS_MESSAGE_TYPE_ERROR;
}
if (!vtable) {
/* Null object pattern, FTW! */
vtable = &null_vtable;
}
type->name = ast_strdup(name);
if (!type->name) {
ao2_cleanup(type);
return STASIS_MESSAGE_TYPE_ERROR;
}
type->hash = ast_hashtab_hash_string(name);
type->vtable = vtable;
if (vtable->to_json) {
type->available_formatters |= STASIS_SUBSCRIPTION_FORMATTER_JSON;
}
if (vtable->to_ami) {
type->available_formatters |= STASIS_SUBSCRIPTION_FORMATTER_AMI;
}
if (vtable->to_event) {
type->available_formatters |= STASIS_SUBSCRIPTION_FORMATTER_EVENT;
}
type->id = ast_atomic_fetchadd_int(&message_type_id, +1);
*result = type;
return STASIS_MESSAGE_TYPE_SUCCESS;
}
const char *stasis_message_type_name(const struct stasis_message_type *type)
{
return type->name;
}
unsigned int stasis_message_type_hash(const struct stasis_message_type *type)
{
return type->hash;
}
int stasis_message_type_id(const struct stasis_message_type *type)
{
return type->id;
}
enum stasis_subscription_message_formatters stasis_message_type_available_formatters(
const struct stasis_message_type *type)
{
return type->available_formatters;
}
/*! \internal */
struct stasis_message {
/*! Time the message was created */
struct timeval timestamp;
/*! Type of the message */
struct stasis_message_type *type;
/*! Where this message originated. NULL if aggregate message. */
const struct ast_eid *eid_ptr;
/*! Message content */
void *data;
/*! Where this message originated. */
struct ast_eid eid;
};
static void stasis_message_dtor(void *obj)
{
struct stasis_message *message = obj;
ao2_cleanup(message->data);
}
struct stasis_message *stasis_message_create_full(struct stasis_message_type *type, void *data, const struct ast_eid *eid)
{
struct stasis_message *message;
if (type == NULL || data == NULL) {
return NULL;
}
message = ao2_t_alloc_options(sizeof(*message), stasis_message_dtor,
AO2_ALLOC_OPT_LOCK_NOLOCK, type->name);
if (message == NULL) {
return NULL;
}
message->timestamp = ast_tvnow();
/*
* XXX Normal ao2 ref counting rules says we should increment the message
* type ref here and decrement it in stasis_message_dtor(). However, the
* stasis message could be cached and legitimately cause the type ref count
* to hit the excessive ref count assertion. Since the message type
* practically has to be a global object anyway, we can get away with not
* holding a ref in the stasis message.
*/
message->type = type;
ao2_ref(data, +1);
message->data = data;
if (eid) {
message->eid_ptr = &message->eid;
message->eid = *eid;
}
return message;
}
struct stasis_message *stasis_message_create(struct stasis_message_type *type, void *data)
{
return stasis_message_create_full(type, data, &ast_eid_default);
}
const struct ast_eid *stasis_message_eid(const struct stasis_message *msg)
{
if (msg == NULL) {
return NULL;
}
return msg->eid_ptr;
}
struct stasis_message_type *stasis_message_type(const struct stasis_message *msg)
{
if (msg == NULL) {
return NULL;
}
return msg->type;
}
void *stasis_message_data(const struct stasis_message *msg)
{
if (msg == NULL) {
return NULL;
}
return msg->data;
}
const struct timeval *stasis_message_timestamp(const struct stasis_message *msg)
{
if (msg == NULL) {
return NULL;
}
return &msg->timestamp;
}
#define INVOKE_VIRTUAL(fn, ...) \
({ \
if (!msg) { \
return NULL; \
} \
ast_assert(msg->type != NULL); \
ast_assert(msg->type->vtable != NULL); \
if (!msg->type->vtable->fn) { \
return NULL; \
} \
msg->type->vtable->fn(__VA_ARGS__); \
})
struct ast_manager_event_blob *stasis_message_to_ami(struct stasis_message *msg)
{
return INVOKE_VIRTUAL(to_ami, msg);
}
struct ast_json *stasis_message_to_json(
struct stasis_message *msg,
struct stasis_message_sanitizer *sanitize)
{
return INVOKE_VIRTUAL(to_json, msg, sanitize);
}
struct ast_event *stasis_message_to_event(struct stasis_message *msg)
{
return INVOKE_VIRTUAL(to_event, msg);
}
#define HAS_VIRTUAL(fn, msg) \
({ \
if (!msg) { \
return 0; \
} \
ast_assert(msg->type != NULL); \
ast_assert(msg->type->vtable != NULL); \
!!msg->type->vtable->fn; \
})
int stasis_message_can_be_ami(struct stasis_message *msg)
{
return HAS_VIRTUAL(to_ami, msg);
}