2 mesh_event_handler.c -- handling of mesh events API
3 Copyright (C) 2018 Guus Sliepen <guus@meshlink.io>
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 2 of the License, or
8 (at your option) any later version.
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
15 You should have received a copy of the GNU General Public License along
16 with this program; if not, write to the Free Software Foundation, Inc.,
17 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
22 #include <netinet/in.h>
23 #include <arpa/inet.h>
24 #include <sys/types.h>
26 #include <sys/ioctl.h>
27 #include <sys/socket.h>
34 #include "../../../src/meshlink_queue.h"
35 #include "../../utils.h"
36 #include "mesh_event_handler.h"
38 #define SERVER_LISTEN_PORT "9000" /* Port number that is binded with mesh event server socket */
39 #define UDP_BUFF_MAX 2000
41 const char *event_status[] = {
42 [NODE_STARTED] = "Node Started",
43 [NODE_JOINED] = "Node Joined",
44 [ERR_NETWORK] = "Network Error",
45 [CHANNEL_OPENED] = "Channel Opened",
46 [CHANNEL_DATA_RECIEVED] = "Channel Data Received",
47 [SIG_ABORT] = "SIG_ABORT Received",
48 [MESH_EVENT_COMPLETED] = "MESH_EVENT_COMPLETED Received"
51 // TODO: Implement mesh event handling with reentrancy .
52 static struct sockaddr_in server_addr;
53 static int client_fd = -1;
54 static int server_fd = -1;
55 static pthread_t event_receive_thread, event_handle_thread;
56 static meshlink_queue_t event_queue;
57 static bool event_receive_thread_running, event_handle_thread_running;
58 static struct cond_flag sync_event = {.mutex = PTHREAD_MUTEX_INITIALIZER, .cond = PTHREAD_COND_INITIALIZER};
60 static void set_cond_flag(struct cond_flag *s, bool flag) {
61 pthread_mutex_lock(&s->mutex);
63 pthread_cond_broadcast(&s->cond);
64 pthread_mutex_unlock(&s->mutex);
67 static bool wait_cond_flag(struct cond_flag *s, int seconds) {
68 struct timespec timeout;
69 clock_gettime(CLOCK_REALTIME, &timeout);
70 timeout.tv_sec += seconds;
72 pthread_mutex_lock(&s->mutex);
75 if(!pthread_cond_timedwait(&s->cond, &s->mutex, &timeout) || errno != EINTR) {
79 pthread_mutex_unlock(&s->mutex);
84 // event_receive_handler running in a separate thread queues all the events received from the UDP port
85 static void *event_receive_handler(void *arg) {
88 char udp_buff[UDP_BUFF_MAX];
89 struct sockaddr client;
92 while(event_receive_thread_running) {
93 recv_ret = recvfrom(server_fd, udp_buff, sizeof(udp_buff), 0, &client, &soc_len);
94 assert(recv_ret >= sizeof(mesh_event_payload_t));
96 // Push received mesh event data into the event_queue
97 mesh_event_payload_t *data = malloc(sizeof(mesh_event_payload_t));
99 memcpy(data, udp_buff, sizeof(mesh_event_payload_t));
101 // Also receive if there is any payload
102 if(data->payload_length) {
103 void *payload_data = malloc(data->payload_length);
104 assert(payload_data);
105 memcpy(payload_data, udp_buff + (int)sizeof(mesh_event_payload_t), data->payload_length);
106 data->payload = payload_data;
108 data->payload = NULL;
111 // Push the event into the event queue
112 assert(meshlink_queue_push(&event_queue, data));
118 // `event_handler' runs in a separate thread which invokes the event handle callback with
119 // event packet as argument returns from the thread when the callback returns `true' or timeout
120 static void *event_handler(void *argv) {
121 bool callback_return = false;
123 mesh_event_payload_t mesh_event_rec_packet;
124 mesh_event_callback_t callback = *(mesh_event_callback_t *)argv;
126 while(event_handle_thread_running) {
128 // Pops the event if found in the event queue
129 while((data = meshlink_queue_pop(&event_queue)) != NULL) {
130 memcpy(&mesh_event_rec_packet, data, sizeof(mesh_event_payload_t));
133 // Invokes the callback with the popped event packet
134 callback_return = callback(mesh_event_rec_packet);
136 if(mesh_event_rec_packet.payload_length) {
137 free(mesh_event_rec_packet.payload);
140 // Return or Close the event handle thread if callback returns true
141 if(callback_return) {
142 set_cond_flag(&sync_event, true);
143 event_handle_thread_running = false;
152 char *mesh_event_sock_create(const char *if_name) {
153 struct sockaddr_in server = {0};
155 struct ifreq req_if = {0};
156 struct sockaddr_in *resp_if_addr;
159 assert(!event_receive_thread_running);
161 server_fd = socket(AF_INET, SOCK_DGRAM, 0);
162 assert(server_fd >= 0);
165 assert(setsockopt(server_fd, SOL_SOCKET, SO_REUSEADDR, &reuse, sizeof(reuse)) != -1);
167 req_if.ifr_addr.sa_family = AF_INET;
168 strncpy(req_if.ifr_name, if_name, IFNAMSIZ - 1);
169 assert(ioctl(server_fd, SIOCGIFADDR, &req_if) != -1);
170 resp_if_addr = (struct sockaddr_in *) & (req_if.ifr_addr);
172 server.sin_family = AF_INET;
173 server.sin_addr = resp_if_addr->sin_addr;
174 server.sin_port = htons(atoi(SERVER_LISTEN_PORT));
175 assert(bind(server_fd, (struct sockaddr *) &server, sizeof(struct sockaddr)) != -1);
177 assert((ip = malloc(30)));
178 strncpy(ip, inet_ntoa(resp_if_addr->sin_addr), 20);
180 strcat(ip, SERVER_LISTEN_PORT);
182 meshlink_queue_init(&event_queue);
183 event_receive_thread_running = true;
184 assert(!pthread_create(&event_receive_thread, NULL, event_receive_handler, NULL));
189 void mesh_event_sock_connect(const char *import) {
192 char *ip = strdup(import);
194 char *port = strchr(ip, ':');
199 memset(&server_addr, 0, sizeof(server_addr));
200 server_addr.sin_family = AF_INET;
201 server_addr.sin_addr.s_addr = inet_addr(ip);
202 server_addr.sin_port = htons(atoi(port));
203 client_fd = socket(AF_INET, SOCK_DGRAM, 0);
205 assert(client_fd >= 0);
208 bool mesh_event_sock_send(int client_id, mesh_event_t event, const void *payload, size_t payload_length) {
210 fprintf(stderr, "mesh_event_sock_send called without calling mesh_event_sock_connect\n");
214 if(client_id < 0 || event < 0 || event >= MAX_EVENT || (payload == NULL && payload_length)) {
215 fprintf(stderr, "Invalid parameters\n");
219 ssize_t send_size = sizeof(mesh_event_payload_t) + payload_length;
220 char *send_packet = malloc(send_size);
222 mesh_event_payload_t mesh_event_send_packet;
224 mesh_event_send_packet.client_id = client_id;
225 mesh_event_send_packet.mesh_event = event;
226 mesh_event_send_packet.payload_length = payload_length;
227 mesh_event_send_packet.payload = NULL;
228 memcpy(send_packet, &mesh_event_send_packet, sizeof(mesh_event_send_packet));
231 memcpy(send_packet + sizeof(mesh_event_send_packet), payload, payload_length);
234 ssize_t send_ret = sendto(client_fd, send_packet, send_size, 0, (const struct sockaddr *) &server_addr, sizeof(server_addr));
238 perror("sendto status");
245 bool wait_for_event(mesh_event_callback_t callback, int seconds) {
246 if(callback == NULL || seconds == 0) {
247 fprintf(stderr, "Invalid parameters\n");
251 if(event_handle_thread_running) {
252 fprintf(stderr, "Event handle thread is already running\n");
255 event_handle_thread_running = true;
258 set_cond_flag(&sync_event, false);
259 assert(!pthread_create(&event_handle_thread, NULL, event_handler, (void *)&callback));
260 bool wait_ret = wait_cond_flag(&sync_event, seconds);
261 event_handle_thread_running = false;
262 pthread_cancel(event_handle_thread);
267 void mesh_events_flush(void) {
268 mesh_event_payload_t *data;
270 while((data = meshlink_queue_pop(&event_queue)) != NULL) {
271 if(data->payload_length) {
279 void mesh_event_destroy(void) {
281 event_receive_thread_running = false;
282 pthread_cancel(event_receive_thread);