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/*
* libwebsockets - small server side websockets and web server implementation
*
* Copyright (C) 2010 - 2019 Andy Green <andy@warmcat.com>
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to
* deal in the Software without restriction, including without limitation the
* rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
* sell copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
* IN THE SOFTWARE.
*/
#include <private-lib-core.h>
#include <private-lib-abstract.h>
extern const lws_abs_transport_t lws_abs_transport_cli_raw_skt,
lws_abs_transport_cli_unit_test;
#if defined(LWS_WITH_SMTP)
extern const lws_abs_protocol_t lws_abs_protocol_smtp;
#endif
#if defined(LWS_WITH_MQTT)
extern const lws_abs_protocol_t lws_abs_protocol_mqttc;
#endif
static const lws_abs_transport_t * const available_abs_transports[] = {
&lws_abs_transport_cli_raw_skt,
&lws_abs_transport_cli_unit_test,
};
#if defined(LWS_WITH_ABSTRACT)
static const lws_abs_protocol_t * const available_abs_protocols[] = {
#if defined(LWS_WITH_SMTP)
&lws_abs_protocol_smtp,
#endif
#if defined(LWS_WITH_MQTT)
&lws_abs_protocol_mqttc,
#endif
};
#endif
const lws_abs_transport_t *
lws_abs_transport_get_by_name(const char *name)
{
int n;
for (n = 0; n < (int)LWS_ARRAY_SIZE(available_abs_transports); n++)
if (!strcmp(name, available_abs_transports[n]->name))
return available_abs_transports[n];
lwsl_err("%s: cannot find '%s'\n", __func__, name);
return NULL;
}
const lws_abs_protocol_t *
lws_abs_protocol_get_by_name(const char *name)
{
#if defined(LWS_WITH_ABSTRACT)
int n;
for (n = 0; n < (int)LWS_ARRAY_SIZE(available_abs_protocols); n++)
if (!strcmp(name, available_abs_protocols[n]->name))
return available_abs_protocols[n];
#endif
lwsl_err("%s: cannot find '%s'\n", __func__, name);
return NULL;
}
const lws_token_map_t *
lws_abs_get_token(const lws_token_map_t *token_map, short name_index)
{
if (!token_map)
return NULL;
do {
if (token_map->name_index == name_index)
return token_map;
token_map++;
} while (token_map->name_index);
return NULL;
}
static int
lws_abstract_compare_connection(lws_abs_t *abs1, lws_abs_t *abs2)
{
/* it has to be using the same protocol */
if (abs1->ap != abs2->ap)
return 1;
/* protocol has to allow some kind of binding */
if (!abs1->ap->flags)
return 1;
/* it has to be using the same transport */
if (abs1->at != abs2->at)
return 1;
/*
* The transport must feel the endpoint and conditions in use match the
* requested endpoint and conditions... and the transport type must be
* willing to allow it
*/
if (abs1->at->compare(abs1, abs2))
return 1;
/*
* The protocol must feel they are in compatible modes if any
* (and the protocol type must be willing to allow it)
*/
if (abs1->ap->compare(abs1, abs2))
return 1;
/*
* If no objection by now, we can say there's already a comparable
* connection and both the protocol and transport feel we can make
* use of it.
*/
return 0;
}
static int
find_compatible(struct lws_dll2 *d, void *user)
{
lws_abs_t *ai1 = (lws_abs_t *)user,
*ai2 = lws_container_of(d, lws_abs_t, abstract_instances);
if (!lws_abstract_compare_connection(ai1, ai2)) {
/* we can bind to it */
lws_dll2_add_tail(&ai1->bound, &ai2->children_owner);
return 1;
}
return 0;
}
lws_abs_t *
lws_abs_bind_and_create_instance(const lws_abs_t *abs)
{
size_t size = sizeof(lws_abs_t) + abs->ap->alloc + abs->at->alloc;
lws_abs_t *ai;
int n;
/*
* since we know we will allocate the lws_abs_t, the protocol's
* instance allocation, and the transport's instance allocation,
* we merge it into a single heap allocation
*/
ai = lws_malloc(size, "abs inst");
if (!ai)
return NULL;
*ai = *abs;
ai->ati = NULL;
ai->api = (char *)ai + sizeof(lws_abs_t);
if (!ai->ap->flags) /* protocol only understands single connections */
goto fresh;
lws_vhost_lock(ai->vh); /* ----------------------------------- vh { */
/*
* Let's have a look for any already-connected transport we can use
*/
n = lws_dll2_foreach_safe(&ai->vh->abstract_instances_owner, ai,
find_compatible);
lws_vhost_unlock(ai->vh); /* } vh --------------------------------- */
if (n)
goto vh_list_add;
/* there's no existing connection doing what we want */
fresh:
ai->ati = (char *)ai->api + abs->ap->alloc;
if (ai->at->create(ai)) {
ai->ati = NULL;
goto bail;
}
vh_list_add:
/* add us to the vhost's dll2 of instances */
lws_dll2_clear(&ai->abstract_instances);
lws_dll2_add_head(&ai->abstract_instances,
&ai->vh->abstract_instances_owner);
if (ai->ap->create(ai)) {
ai->api = NULL;
goto bail;
}
if (ai->bound.owner) { /* we are a piggybacker */
lws_abs_t *ai2 = lws_container_of(ai->bound.owner, lws_abs_t,
children_owner);
/*
* Provide an 'event' in the parent context to start handling
* the bind if it's otherwise idle. We give the parent abs
* because we don't know if we're "next" or whatever. Just that
* a child joined him and he should look into his child
* situation in case he was waiting for one to appear.
*/
if (ai2->ap->child_bind(ai2)) {
lwsl_info("%s: anticpated child bind fail\n", __func__);
lws_dll2_remove(&ai->bound);
goto bail;
}
}
return ai;
bail:
lws_abs_destroy_instance(&ai);
return NULL;
}
/*
* We get called to clean up each child that was still bound to a parent
* at the time the parent is getting destroyed.
*/
static void
__lws_abs_destroy_instance2(lws_abs_t **ai)
{
lws_abs_t *a = *ai;
if (a->api)
a->ap->destroy(&a->api);
if (a->ati)
a->at->destroy(&a->ati);
lws_dll2_remove(&a->abstract_instances);
*ai = NULL;
free(a);
}
static int
__reap_children(struct lws_dll2 *d, void *user)
{
lws_abs_t *ac = lws_container_of(d, lws_abs_t, bound);
lws_dll2_foreach_safe(&ac->children_owner, NULL, __reap_children);
/* then destroy ourselves */
__lws_abs_destroy_instance2(&ac);
return 0;
}
void
lws_abs_destroy_instance(lws_abs_t **ai)
{
lws_abs_t *a = *ai;
/* destroy child instances that are bound to us first... */
lws_vhost_lock(a->vh); /* ----------------------------------- vh { */
lws_dll2_foreach_safe(&a->children_owner, NULL, __reap_children);
/* ...then destroy ourselves */
__lws_abs_destroy_instance2(ai);
lws_vhost_unlock(a->vh); /* } vh --------------------------------- */
}
lws_abs_t *
lws_abstract_alloc(struct lws_vhost *vhost, void *user,
const char *abstract_path, const lws_token_map_t *ap_tokens,
const lws_token_map_t *at_tokens, struct lws_sequencer *seq,
void *opaque_user_data)
{
lws_abs_t *abs = lws_zalloc(sizeof(*abs), __func__);
struct lws_tokenize ts;
lws_tokenize_elem e;
char tmp[30];
if (!abs)
return NULL;
lws_tokenize_init(&ts, abstract_path, LWS_TOKENIZE_F_MINUS_NONTERM);
e = lws_tokenize(&ts);
if (e != LWS_TOKZE_TOKEN)
goto abs_path_problem;
if (lws_tokenize_cstr(&ts, tmp, sizeof(tmp)))
goto abs_path_problem;
abs->ap = lws_abs_protocol_get_by_name(tmp);
if (!abs->ap)
goto abs_path_problem;
e = lws_tokenize(&ts);
if (e != LWS_TOKZE_DELIMITER)
goto abs_path_problem;
e = lws_tokenize(&ts);
if (e != LWS_TOKZE_TOKEN)
goto abs_path_problem;
if (lws_tokenize_cstr(&ts, tmp, sizeof(tmp)))
goto abs_path_problem;
abs->at = lws_abs_transport_get_by_name(tmp);
if (!abs->at)
goto abs_path_problem;
abs->vh = vhost;
abs->ap_tokens = ap_tokens;
abs->at_tokens = at_tokens;
abs->seq = seq;
abs->opaque_user_data = opaque_user_data;
lwsl_info("%s: allocated %s\n", __func__, abstract_path);
return abs;
abs_path_problem:
lwsl_err("%s: bad abs path '%s'\n", __func__, abstract_path);
lws_free_set_NULL(abs);
return NULL;
}
void
lws_abstract_free(lws_abs_t **pabs)
{
if (*pabs)
lws_free_set_NULL(*pabs);
}