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|
/*
* Copyright (C) 2015, 2016, 2017 "IoT.bzh"
* Author José Bollo <jose.bollo@iot.bzh>
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#define _GNU_SOURCE
#define NO_PLUGIN_VERBOSE_MACRO
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <assert.h>
#include <errno.h>
#include <systemd/sd-bus.h>
#include <json-c/json.h>
#include <afb/afb-event-itf.h>
#include "afb-common.h"
#include "afb-session.h"
#include "afb-msg-json.h"
#include "afb-api.h"
#include "afb-apiset.h"
#include "afb-api-dbus.h"
#include "afb-context.h"
#include "afb-cred.h"
#include "afb-evt.h"
#include "afb-xreq.h"
#include "verbose.h"
static const char DEFAULT_PATH_PREFIX[] = "/org/agl/afb/api/";
struct dbus_memo;
struct dbus_event;
struct origin;
/*
* The path given are of the form
* system:/org/agl/afb/api/...
* or
* user:/org/agl/afb/api/...
*/
struct api_dbus
{
struct sd_bus *sdbus; /* the bus */
char *path; /* path of the object for the API */
char *name; /* name/interface of the object */
char *api; /* api name of the interface */
union {
struct {
struct sd_bus_slot *slot_broadcast;
struct sd_bus_slot *slot_event;
struct dbus_event *events;
struct dbus_memo *memos;
} client;
struct {
struct sd_bus_slot *slot_call;
struct afb_evt_listener *listener; /* listener for broadcasted events */
struct origin *origins;
struct afb_apiset *apiset;
} server;
};
};
#define RETOK 1
#define RETERR 2
/******************* common part **********************************/
/*
* create a structure api_dbus connected on either the system
* bus if 'system' is not null or on the user bus. The connection
* is established for either emiting/receiving on 'path' being of length
* 'pathlen'.
*/
static struct api_dbus *make_api_dbus_3(int system, const char *path, size_t pathlen)
{
struct api_dbus *api;
struct sd_bus *sdbus;
char *ptr;
/* allocates the structure */
api = calloc(1, sizeof *api + 1 + pathlen + pathlen);
if (api == NULL) {
errno = ENOMEM;
goto error;
}
/* init the structure's strings */
/* path is copied after the struct */
api->path = (void*)(api+1);
strcpy(api->path, path);
/* api name is at the end of the path */
api->api = strrchr(api->path, '/');
if (api->api == NULL) {
errno = EINVAL;
goto error2;
}
api->api++;
if (!afb_api_is_valid_name(api->api)) {
errno = EINVAL;
goto error2;
}
/* the name/interface is copied after the path */
api->name = &api->path[pathlen + 1];
strcpy(api->name, &path[1]);
ptr = strchr(api->name, '/');
while(ptr != NULL) {
*ptr = '.';
ptr = strchr(ptr, '/');
}
/* choose the bus */
sdbus = (system ? afb_common_get_system_bus : afb_common_get_user_bus)();
if (sdbus == NULL)
goto error2;
api->sdbus = sdbus;
return api;
error2:
free(api);
error:
return NULL;
}
/*
* create a structure api_dbus connected on either the system
* bus if 'system' is not null or on the user bus. The connection
* is established for either emiting/receiving on 'path'.
* If 'path' is not absolute, it is prefixed with DEFAULT_PATH_PREFIX.
*/
static struct api_dbus *make_api_dbus_2(int system, const char *path)
{
size_t len;
char *ptr;
/* check the length of the path */
len = strlen(path);
if (len == 0) {
errno = EINVAL;
return NULL;
}
/* if the path is absolute, creation now */
if (path[0] == '/')
return make_api_dbus_3(system, path, len);
/* compute the path prefixed with DEFAULT_PATH_PREFIX */
assert(strlen(DEFAULT_PATH_PREFIX) > 0);
assert(DEFAULT_PATH_PREFIX[strlen(DEFAULT_PATH_PREFIX) - 1] == '/');
len += strlen(DEFAULT_PATH_PREFIX);
ptr = alloca(len + 1);
strcpy(stpcpy(ptr, DEFAULT_PATH_PREFIX), path);
/* creation for prefixed path */
return make_api_dbus_3(system, ptr, len);
}
/*
* create a structure api_dbus connected either emiting/receiving
* on 'path'.
* The path can be prefixed with "system:" or "user:" to select
* either the user or the system D-Bus. If none is set then user's
* bus is selected.
* If remaining 'path' is not absolute, it is prefixed with
* DEFAULT_PATH_PREFIX.
*/
static struct api_dbus *make_api_dbus(const char *path)
{
const char *ptr;
size_t preflen;
/* retrieves the prefix "scheme-like" part */
ptr = strchr(path, ':');
if (ptr == NULL)
return make_api_dbus_2(0, path);
/* check the prefix part */
preflen = (size_t)(ptr - path);
if (strncmp(path, "system", preflen) == 0)
return make_api_dbus_2(1, ptr + 1);
if (strncmp(path, "user", preflen) == 0)
return make_api_dbus_2(0, ptr + 1);
/* TODO: connect to a foreign D-Bus? */
errno = EINVAL;
return NULL;
}
static void destroy_api_dbus(struct api_dbus *api)
{
free(api);
}
/******************* client part **********************************/
/*
* structure for recording query data
*/
struct dbus_memo {
struct dbus_memo *next; /* the next memo */
struct api_dbus *api; /* the dbus api */
struct afb_xreq *xreq; /* the request */
uint64_t msgid; /* the message identifier */
};
struct dbus_event
{
struct dbus_event *next;
struct afb_event event;
int id;
int refcount;
};
/* allocates and init the memorizing data */
static struct dbus_memo *api_dbus_client_memo_make(struct api_dbus *api, struct afb_xreq *xreq)
{
struct dbus_memo *memo;
memo = malloc(sizeof *memo);
if (memo != NULL) {
afb_xreq_unhooked_addref(xreq);
memo->xreq = xreq;
memo->msgid = 0;
memo->api = api;
memo->next = api->client.memos;
api->client.memos = memo;
}
return memo;
}
/* free and release the memorizing data */
static void api_dbus_client_memo_destroy(struct dbus_memo *memo)
{
struct dbus_memo **prv;
prv = &memo->api->client.memos;
while (*prv != NULL) {
if (*prv == memo) {
*prv = memo->next;
break;
}
prv = &(*prv)->next;
}
afb_xreq_unhooked_unref(memo->xreq);
free(memo);
}
/* search a memorized request */
static struct dbus_memo *api_dbus_client_memo_search(struct api_dbus *api, uint64_t msgid)
{
struct dbus_memo *memo;
memo = api->client.memos;
while (memo != NULL && memo->msgid != msgid)
memo = memo->next;
return memo;
}
/* callback when received answer */
static int api_dbus_client_on_reply(sd_bus_message *message, void *userdata, sd_bus_error *ret_error)
{
int rc;
struct dbus_memo *memo;
const char *first, *second;
uint8_t type;
uint32_t flags;
/* retrieve the recorded data */
memo = userdata;
/* get the answer */
rc = sd_bus_message_read(message, "yssu", &type, &first, &second, &flags);
if (rc < 0) {
/* failing to have the answer */
afb_xreq_fail(memo->xreq, "error", "dbus error");
} else {
/* report the answer */
memo->xreq->context.flags = (unsigned)flags;
switch(type) {
case RETOK:
afb_xreq_success(memo->xreq, json_tokener_parse(first), *second ? second : NULL);
break;
case RETERR:
afb_xreq_fail(memo->xreq, first, *second ? second : NULL);
break;
default:
afb_xreq_fail(memo->xreq, "error", "dbus link broken");
break;
}
}
api_dbus_client_memo_destroy(memo);
return 1;
}
/* on call, propagate it to the dbus service */
static void api_dbus_client_call(void *closure, struct afb_xreq *xreq)
{
struct api_dbus *api = closure;
size_t size;
int rc;
struct dbus_memo *memo;
struct sd_bus_message *msg;
/* create the recording data */
memo = api_dbus_client_memo_make(api, xreq);
if (memo == NULL) {
afb_xreq_fail(xreq, "error", "out of memory");
return;
}
/* creates the message */
msg = NULL;
rc = sd_bus_message_new_method_call(api->sdbus, &msg, api->name, api->path, api->name, xreq->verb);
if (rc < 0)
goto error;
rc = sd_bus_message_append(msg, "ssu",
afb_xreq_raw(xreq, &size),
afb_session_uuid(xreq->context.session),
(uint32_t)xreq->context.flags);
if (rc < 0)
goto error;
/* makes the call */
rc = sd_bus_call_async(api->sdbus, NULL, msg, api_dbus_client_on_reply, memo, (uint64_t)-1);
if (rc < 0)
goto error;
rc = sd_bus_message_get_cookie(msg, &memo->msgid);
if (rc >= 0)
goto end;
error:
/* if there was an error report it directly */
errno = -rc;
afb_xreq_fail(xreq, "error", "dbus error");
api_dbus_client_memo_destroy(memo);
end:
sd_bus_message_unref(msg);
}
/* receives broadcasted events */
static int api_dbus_client_on_broadcast_event(sd_bus_message *m, void *userdata, sd_bus_error *ret_error)
{
struct json_object *object;
const char *event, *data;
int rc = sd_bus_message_read(m, "ss", &event, &data);
if (rc < 0)
ERROR("unreadable broadcasted event");
else {
object = json_tokener_parse(data);
afb_evt_broadcast(event, object);
}
return 1;
}
/* search the event */
static struct dbus_event *api_dbus_client_event_search(struct api_dbus *api, int id, const char *name)
{
struct dbus_event *ev;
ev = api->client.events;
while (ev != NULL && (ev->id != id || 0 != strcmp(afb_evt_event_fullname(ev->event), name)))
ev = ev->next;
return ev;
}
/* adds an event */
static void api_dbus_client_event_create(struct api_dbus *api, int id, const char *name)
{
struct dbus_event *ev;
/* check conflicts */
ev = api_dbus_client_event_search(api, id, name);
if (ev != NULL) {
ev->refcount++;
return;
}
/* no conflict, try to add it */
ev = malloc(sizeof *ev);
if (ev != NULL) {
ev->event = afb_evt_create_event(name);
if (ev->event.closure == NULL)
free(ev);
else {
ev->refcount = 1;
ev->id = id;
ev->next = api->client.events;
api->client.events = ev;
return;
}
}
ERROR("can't create event %s, out of memory", name);
}
/* removes an event */
static void api_dbus_client_event_drop(struct api_dbus *api, int id, const char *name)
{
struct dbus_event *ev, **prv;
/* retrieves the event */
ev = api_dbus_client_event_search(api, id, name);
if (ev == NULL) {
ERROR("event %s not found", name);
return;
}
/* decrease the reference count */
if (--ev->refcount)
return;
/* unlinks the event */
prv = &api->client.events;
while (*prv != ev)
prv = &(*prv)->next;
*prv = ev->next;
/* destroys the event */
afb_event_unref(ev->event);
free(ev);
}
/* pushs an event */
static void api_dbus_client_event_push(struct api_dbus *api, int id, const char *name, const char *data)
{
struct json_object *object;
struct dbus_event *ev;
/* retrieves the event */
ev = api_dbus_client_event_search(api, id, name);
if (ev == NULL) {
ERROR("event %s not found", name);
return;
}
/* destroys the event */
object = json_tokener_parse(data);
afb_event_push(ev->event, object);
}
/* subscribes an event */
static void api_dbus_client_event_subscribe(struct api_dbus *api, int id, const char *name, uint64_t msgid)
{
int rc;
struct dbus_event *ev;
struct dbus_memo *memo;
/* retrieves the event */
ev = api_dbus_client_event_search(api, id, name);
if (ev == NULL) {
ERROR("event %s not found", name);
return;
}
/* retrieves the memo */
memo = api_dbus_client_memo_search(api, msgid);
if (memo == NULL) {
ERROR("message not found");
return;
}
/* subscribe the request to the event */
rc = afb_xreq_subscribe(memo->xreq, ev->event);
if (rc < 0)
ERROR("can't subscribe: %m");
}
/* unsubscribes an event */
static void api_dbus_client_event_unsubscribe(struct api_dbus *api, int id, const char *name, uint64_t msgid)
{
int rc;
struct dbus_event *ev;
struct dbus_memo *memo;
/* retrieves the event */
ev = api_dbus_client_event_search(api, id, name);
if (ev == NULL) {
ERROR("event %s not found", name);
return;
}
/* retrieves the memo */
memo = api_dbus_client_memo_search(api, msgid);
if (memo == NULL) {
ERROR("message not found");
return;
}
/* unsubscribe the request from the event */
rc = afb_xreq_unsubscribe(memo->xreq, ev->event);
if (rc < 0)
ERROR("can't unsubscribe: %m");
}
/* receives calls for event */
static int api_dbus_client_on_manage_event(sd_bus_message *m, void *userdata, sd_bus_error *ret_error)
{
const char *eventname, *data;
int rc;
int32_t eventid;
uint8_t order;
struct api_dbus *api;
uint64_t msgid;
/* check if expected message */
api = userdata;
if (0 != strcmp(api->name, sd_bus_message_get_interface(m)))
return 0; /* not the expected interface */
if (0 != strcmp("event", sd_bus_message_get_member(m)))
return 0; /* not the expected member */
if (sd_bus_message_get_expect_reply(m))
return 0; /* not the expected type of message */
/* reads the message */
rc = sd_bus_message_read(m, "yisst", &order, &eventid, &eventname, &data, &msgid);
if (rc < 0) {
ERROR("unreadable event");
return 1;
}
/* what is the order ? */
switch ((char)order) {
case '+': /* creates the event */
api_dbus_client_event_create(api, eventid, eventname);
break;
case '-': /* drops the event */
api_dbus_client_event_drop(api, eventid, eventname);
break;
case '!': /* pushs the event */
api_dbus_client_event_push(api, eventid, eventname, data);
break;
case 'S': /* subscribe event for a request */
api_dbus_client_event_subscribe(api, eventid, eventname, msgid);
break;
case 'U': /* unsubscribe event for a request */
api_dbus_client_event_unsubscribe(api, eventid, eventname, msgid);
break;
default:
/* unexpected order */
ERROR("unexpected order '%c' received", (char)order);
break;
}
return 1;
}
static struct afb_api_itf dbus_api_itf = {
.call = api_dbus_client_call
};
/* adds a afb-dbus-service client api */
int afb_api_dbus_add_client(const char *path, struct afb_apiset *apiset)
{
int rc;
struct api_dbus *api;
struct afb_api afb_api;
char *match;
/* create the dbus client api */
api = make_api_dbus(path);
if (api == NULL)
goto error;
/* connect to broadcasted events */
rc = asprintf(&match, "type='signal',path='%s',interface='%s',member='broadcast'", api->path, api->name);
if (rc < 0) {
errno = ENOMEM;
ERROR("out of memory");
goto error;
}
rc = sd_bus_add_match(api->sdbus, &api->client.slot_broadcast, match, api_dbus_client_on_broadcast_event, api);
free(match);
if (rc < 0) {
errno = -rc;
ERROR("can't add dbus match %s for %s", api->path, api->name);
goto error;
}
/* connect to event management */
rc = sd_bus_add_object(api->sdbus, &api->client.slot_event, api->path, api_dbus_client_on_manage_event, api);
if (rc < 0) {
errno = -rc;
ERROR("can't add dbus object %s for %s", api->path, api->name);
goto error;
}
/* record it as an API */
afb_api.closure = api;
afb_api.itf = &dbus_api_itf;
afb_api.group = NULL;
if (afb_apiset_add(apiset, api->api, afb_api) < 0)
goto error2;
return 0;
error2:
destroy_api_dbus(api);
error:
return -1;
}
/******************* event structures for server part **********************************/
static void afb_api_dbus_server_event_add(void *closure, const char *event, int eventid);
static void afb_api_dbus_server_event_remove(void *closure, const char *event, int eventid);
static void afb_api_dbus_server_event_push(void *closure, const char *event, int eventid, struct json_object *object);
static void afb_api_dbus_server_event_broadcast(void *closure, const char *event, int eventid, struct json_object *object);
/* the interface for events broadcasting */
static const struct afb_evt_itf evt_broadcast_itf = {
.broadcast = afb_api_dbus_server_event_broadcast,
};
/* the interface for events pushing */
static const struct afb_evt_itf evt_push_itf = {
.push = afb_api_dbus_server_event_push,
.add = afb_api_dbus_server_event_add,
.remove = afb_api_dbus_server_event_remove
};
/******************* origin description part for server *****************************/
struct origin
{
/* link to next different origin */
struct origin *next;
/* the server dbus-api */
struct api_dbus *api;
/* count of references */
int refcount;
/* credentials of the origin */
struct afb_cred *cred;
/* the origin */
char name[1];
};
/* get the credentials for the message */
static void init_origin_creds(struct origin *origin)
{
int rc;
sd_bus_creds *c;
uid_t uid;
gid_t gid;
pid_t pid;
const char *context;
rc = sd_bus_get_name_creds(origin->api->sdbus, origin->name,
SD_BUS_CREDS_PID|SD_BUS_CREDS_UID|SD_BUS_CREDS_GID|SD_BUS_CREDS_SELINUX_CONTEXT,
&c);
if (rc < 0)
origin->cred = NULL;
else {
afb_cred_unref(origin->cred);
sd_bus_creds_get_uid(c, &uid);
sd_bus_creds_get_gid(c, &gid);
sd_bus_creds_get_pid(c, &pid);
sd_bus_creds_get_selinux_context(c, &context);
origin->cred = afb_cred_create(uid, gid, pid, context);
sd_bus_creds_unref(c);
}
}
static struct origin *afb_api_dbus_server_origin_get(struct api_dbus *api, const char *sender)
{
struct origin *origin;
/* searchs for an existing origin */
origin = api->server.origins;
while (origin != NULL) {
if (0 == strcmp(origin->name, sender)) {
origin->refcount++;
return origin;
}
origin = origin->next;
}
/* not found, create it */
origin = malloc(strlen(sender) + sizeof *origin);
if (origin == NULL)
errno = ENOMEM;
else {
origin->api = api;
origin->refcount = 1;
strcpy(origin->name, sender);
init_origin_creds(origin);
origin->next = api->server.origins;
api->server.origins = origin;
}
return origin;
}
static void afb_api_dbus_server_origin_unref(struct origin *origin)
{
if (!--origin->refcount) {
struct origin **prv;
prv = &origin->api->server.origins;
while(*prv != origin)
prv = &(*prv)->next;
*prv = origin->next;
afb_cred_unref(origin->cred);
free(origin);
}
}
struct listener
{
/* link to next different origin */
struct origin *origin;
/* the listener of events */
struct afb_evt_listener *listener;
};
static void afb_api_dbus_server_listener_free(struct listener *listener)
{
afb_evt_listener_unref(listener->listener);
afb_api_dbus_server_origin_unref(listener->origin);
free(listener);
}
static struct listener *afb_api_dbus_server_listener_get(struct api_dbus *api, const char *sender, struct afb_session *session)
{
int rc;
struct listener *listener;
struct origin *origin;
/* get the origin */
origin = afb_api_dbus_server_origin_get(api, sender);
if (origin == NULL)
return NULL;
/* retrieves the stored listener */
listener = afb_session_get_cookie(session, origin);
if (listener != NULL) {
/* found */
afb_api_dbus_server_origin_unref(origin);
return listener;
}
/* creates the listener */
listener = malloc(sizeof *listener);
if (listener == NULL)
errno = ENOMEM;
else {
listener->origin = origin;
listener->listener = afb_evt_listener_create(&evt_push_itf, origin);
if (listener->listener != NULL) {
rc = afb_session_set_cookie(session, origin, listener, (void*)afb_api_dbus_server_listener_free);
if (rc == 0)
return listener;
afb_evt_listener_unref(listener->listener);
}
free(listener);
}
afb_api_dbus_server_origin_unref(origin);
return NULL;
}
/******************* dbus request part for server *****************/
/**
* Structure for a dbus request
*/
struct dbus_req {
struct afb_xreq xreq; /**< the xreq of the request */
sd_bus_message *message; /**< the incoming request message */
const char *request; /**< the readen request as string */
struct json_object *json; /**< the readen request as object */
struct listener *listener; /**< the listener for events */
};
/* decrement the reference count of the request and free/release it on falling to null */
static void dbus_req_destroy(struct afb_xreq *xreq)
{
struct dbus_req *dreq = CONTAINER_OF_XREQ(struct dbus_req, xreq);
afb_context_disconnect(&dreq->xreq.context);
json_object_put(dreq->json);
sd_bus_message_unref(dreq->message);
free(dreq);
}
/* get the object of the request */
static struct json_object *dbus_req_json(struct afb_xreq *xreq)
{
struct dbus_req *dreq = CONTAINER_OF_XREQ(struct dbus_req, xreq);
return dreq->json;
}
/* get the argument of the request of 'name' */
static void dbus_req_reply(struct dbus_req *dreq, uint8_t type, const char *first, const char *second)
{
int rc;
rc = sd_bus_reply_method_return(dreq->message,
"yssu", type, first ? : "", second ? : "", (uint32_t)dreq->xreq.context.flags);
if (rc < 0)
ERROR("sending the reply failed");
}
static void dbus_req_success(struct afb_xreq *xreq, struct json_object *obj, const char *info)
{
struct dbus_req *dreq = CONTAINER_OF_XREQ(struct dbus_req, xreq);
dbus_req_reply(dreq, RETOK, json_object_to_json_string_ext(obj, JSON_C_TO_STRING_PLAIN), info);
}
static void dbus_req_fail(struct afb_xreq *xreq, const char *status, const char *info)
{
struct dbus_req *dreq = CONTAINER_OF_XREQ(struct dbus_req, xreq);
dbus_req_reply(dreq, RETERR, status, info);
}
static void afb_api_dbus_server_event_send(struct origin *origin, char order, const char *event, int eventid, const char *data, uint64_t msgid);
static int dbus_req_subscribe(struct afb_xreq *xreq, struct afb_event event)
{
struct dbus_req *dreq = CONTAINER_OF_XREQ(struct dbus_req, xreq);
uint64_t msgid;
int rc;
rc = afb_evt_add_watch(dreq->listener->listener, event);
sd_bus_message_get_cookie(dreq->message, &msgid);
afb_api_dbus_server_event_send(dreq->listener->origin, 'S', afb_evt_event_fullname(event), afb_evt_event_id(event), "", msgid);
return rc;
}
static int dbus_req_unsubscribe(struct afb_xreq *xreq, struct afb_event event)
{
struct dbus_req *dreq = CONTAINER_OF_XREQ(struct dbus_req, xreq);
uint64_t msgid;
int rc;
sd_bus_message_get_cookie(dreq->message, &msgid);
afb_api_dbus_server_event_send(dreq->listener->origin, 'U', afb_evt_event_fullname(event), afb_evt_event_id(event), "", msgid);
rc = afb_evt_remove_watch(dreq->listener->listener, event);
return rc;
}
const struct afb_xreq_query_itf afb_api_dbus_xreq_itf = {
.json = dbus_req_json,
.success = dbus_req_success,
.fail = dbus_req_fail,
.unref = dbus_req_destroy,
.subscribe = dbus_req_subscribe,
.unsubscribe = dbus_req_unsubscribe
};
/******************* server part **********************************/
static void afb_api_dbus_server_event_send(struct origin *origin, char order, const char *event, int eventid, const char *data, uint64_t msgid)
{
int rc;
struct api_dbus *api;
struct sd_bus_message *msg;
api = origin->api;
msg = NULL;
rc = sd_bus_message_new_method_call(api->sdbus, &msg, origin->name, api->path, api->name, "event");
if (rc < 0)
goto error;
rc = sd_bus_message_append(msg, "yisst", (uint8_t)order, (int32_t)eventid, event, data, msgid);
if (rc < 0)
goto error;
rc = sd_bus_send(api->sdbus, msg, NULL); /* NULL for cookie implies no expected reply */
if (rc >= 0)
goto end;
error:
ERROR("error while send event %c%s(%d) to %s", order, event, eventid, origin->name);
end:
sd_bus_message_unref(msg);
}
static void afb_api_dbus_server_event_add(void *closure, const char *event, int eventid)
{
afb_api_dbus_server_event_send(closure, '+', event, eventid, "", 0);
}
static void afb_api_dbus_server_event_remove(void *closure, const char *event, int eventid)
{
afb_api_dbus_server_event_send(closure, '-', event, eventid, "", 0);
}
static void afb_api_dbus_server_event_push(void *closure, const char *event, int eventid, struct json_object *object)
{
const char *data = json_object_to_json_string_ext(object, JSON_C_TO_STRING_PLAIN);
afb_api_dbus_server_event_send(closure, '!', event, eventid, data, 0);
json_object_put(object);
}
static void afb_api_dbus_server_event_broadcast(void *closure, const char *event, int eventid, struct json_object *object)
{
int rc;
struct api_dbus *api;
api = closure;
rc = sd_bus_emit_signal(api->sdbus, api->path, api->name, "broadcast",
"ss", event, json_object_to_json_string_ext(object, JSON_C_TO_STRING_PLAIN));
if (rc < 0)
ERROR("error while broadcasting event %s", event);
json_object_put(object);
}
/* called when the object for the service is called */
static int api_dbus_server_on_object_called(sd_bus_message *message, void *userdata, sd_bus_error *ret_error)
{
int rc;
const char *method;
const char *uuid;
struct dbus_req *dreq;
struct api_dbus *api = userdata;
uint32_t flags;
struct afb_session *session;
struct listener *listener;
/* check the interface */
if (strcmp(sd_bus_message_get_interface(message), api->name) != 0)
return 0;
/* get the method */
method = sd_bus_message_get_member(message);
/* create the request */
dreq = calloc(1 , sizeof *dreq);
if (dreq == NULL)
goto out_of_memory;
/* get the data */
rc = sd_bus_message_read(message, "ssu", &dreq->request, &uuid, &flags);
if (rc < 0) {
sd_bus_reply_method_errorf(message, SD_BUS_ERROR_INVALID_SIGNATURE, "invalid signature");
goto error;
}
/* connect to the context */
afb_xreq_init(&dreq->xreq, &afb_api_dbus_xreq_itf);
if (afb_context_connect(&dreq->xreq.context, uuid, NULL) < 0)
goto out_of_memory;
session = dreq->xreq.context.session;
/* get the listener */
listener = afb_api_dbus_server_listener_get(api, sd_bus_message_get_sender(message), session);
if (listener == NULL)
goto out_of_memory;
/* fulfill the request and emit it */
dreq->xreq.context.flags = flags;
dreq->message = sd_bus_message_ref(message);
dreq->json = json_tokener_parse(dreq->request);
if (dreq->json == NULL && strcmp(dreq->request, "null")) {
/* lazy error detection of json request. Is it to improve? */
dreq->json = json_object_new_string(dreq->request);
}
dreq->listener = listener;
dreq->xreq.api = api->api;
dreq->xreq.verb = method;
afb_xreq_process(&dreq->xreq, api->server.apiset);
return 1;
out_of_memory:
sd_bus_reply_method_errorf(message, SD_BUS_ERROR_NO_MEMORY, "out of memory");
error:
free(dreq);
return 1;
}
/* create the service */
int afb_api_dbus_add_server(const char *path, struct afb_apiset *apiset)
{
int rc;
struct api_dbus *api;
/* get the dbus api object connected */
api = make_api_dbus(path);
if (api == NULL)
goto error;
/* request the service object name */
rc = sd_bus_request_name(api->sdbus, api->name, 0);
if (rc < 0) {
errno = -rc;
ERROR("can't register name %s", api->name);
goto error2;
}
/* connect the service to the dbus object */
rc = sd_bus_add_object(api->sdbus, &api->server.slot_call, api->path, api_dbus_server_on_object_called, api);
if (rc < 0) {
errno = -rc;
ERROR("can't add dbus object %s for %s", api->path, api->name);
goto error3;
}
INFO("afb service over dbus installed, name %s, path %s", api->name, api->path);
api->server.listener = afb_evt_listener_create(&evt_broadcast_itf, api);
api->server.apiset = afb_apiset_addref(apiset);
return 0;
error3:
sd_bus_release_name(api->sdbus, api->name);
error2:
destroy_api_dbus(api);
error:
return -1;
}
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