]> git.meshlink.io Git - utcp/blob - test.c
Simulate packet reordering.
[utcp] / test.c
1 #define _GNU_SOURCE
2
3 #include <stdio.h>
4 #include <stdlib.h>
5 #include <stdarg.h>
6 #include <string.h>
7 #include <time.h>
8 #include <errno.h>
9 #include <sys/types.h>
10 #include <sys/socket.h>
11 #include <netdb.h>
12 #include <poll.h>
13
14
15 #include "utcp.h"
16
17 #define DIR_READ 1
18 #define DIR_WRITE 2
19
20 struct utcp_connection *c;
21 int dir = DIR_READ | DIR_WRITE;
22 bool running = true;
23 long inpktno;
24 long outpktno;
25 long dropfrom;
26 long dropto;
27 double reorder;
28 long reorder_dist;
29 double dropin;
30 double dropout;
31 long total_out;
32 long total_in;
33
34 char *reorder_data;
35 size_t reorder_len;
36 int reorder_countdown;
37
38 void debug(const char *format, ...) {
39         struct timeval now;
40         gettimeofday(&now, NULL);
41         fprintf(stderr, "%lu.%lu ", now.tv_sec, now.tv_usec / 1000);
42         va_list ap;
43         va_start(ap, format);
44         vfprintf(stderr, format, ap);
45         va_end(ap);
46 }
47
48 ssize_t do_recv(struct utcp_connection *c, const void *data, size_t len) {
49         if(!data || !len) {
50                 if(errno) {
51                         debug("Error: %s\n", strerror(errno));
52                         dir = 0;
53                 } else {
54                         dir &= ~DIR_WRITE;
55                         debug("Connection closed by peer\n");
56                 }
57                 return -1;
58         }
59         return write(1, data, len);
60 }
61
62 void do_accept(struct utcp_connection *nc, uint16_t port) {
63         utcp_accept(nc, do_recv, NULL);
64         c = nc;
65         utcp_set_accept_cb(c->utcp, NULL, NULL);
66 }
67
68 ssize_t do_send(struct utcp *utcp, const void *data, size_t len) {
69         int s = *(int *)utcp->priv;
70         outpktno++;
71         if(outpktno >= dropfrom && outpktno < dropto) {
72                 if(drand48() < dropout)
73                         return len;
74                 if(!reorder_data && drand48() < reorder) {
75                         reorder_data = malloc(len);
76                         reorder_len = len;
77                         memcpy(reorder_data, data, len);
78                         reorder_countdown = 1 + drand48() * reorder_dist;
79                         return len;
80                 }
81         }
82
83         if(reorder_data) {
84                 if(--reorder_countdown < 0) {
85                         total_out += reorder_len;
86                         send(s, reorder_data, reorder_len, MSG_DONTWAIT);
87                         free(reorder_data);
88                         reorder_data = NULL;
89                 }
90         }
91
92         total_out += len;
93         ssize_t result = send(s, data, len, MSG_DONTWAIT);
94         if(result <= 0)
95                 debug("Error sending UDP packet: %s\n", strerror(errno));
96         return result;
97 }
98
99 int main(int argc, char *argv[]) {
100         srand(time(NULL));
101         srand48(time(NULL));
102
103         if(argc < 2 || argc > 3)
104                 return 1;
105
106         bool server = argc == 2;
107         bool connected = false;
108
109         dropin = atof(getenv("DROPIN") ?: "0");
110         dropout = atof(getenv("DROPOUT") ?: "0");
111         dropfrom = atoi(getenv("DROPFROM") ?: "0");
112         dropto = atoi(getenv("DROPTO") ?: "0");
113         reorder = atof(getenv("REORDER") ?: "0");
114         reorder_dist = atoi(getenv("REORDER_DIST") ?: "10");
115
116         struct addrinfo *ai;
117         struct addrinfo hint = {
118                 .ai_flags = server ? AI_PASSIVE : 0,
119                 .ai_socktype = SOCK_DGRAM,
120         };
121
122         getaddrinfo(server ? NULL : argv[1], server ? argv[1] : argv[2], &hint, &ai);
123         if(!ai)
124                 return 1;
125
126         int s = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
127         if(s == -1)
128                 return 1;
129
130         if(server) {
131                 if(bind(s, ai->ai_addr, ai->ai_addrlen))
132                         return 1;
133         } else {
134                 if(connect(s, ai->ai_addr, ai->ai_addrlen))
135                         return 1;
136                 connected = true;
137         }
138
139         freeaddrinfo(ai);
140
141         struct utcp *u = utcp_init(server ? do_accept : NULL, NULL, do_send, &s);
142         if(!u)
143                 return 1;
144
145         utcp_set_mtu(u, 1300);
146         utcp_set_user_timeout(u, 10);
147
148         if(!server)
149                 c = utcp_connect(u, 1, do_recv, NULL);
150
151         struct pollfd fds[2] = {
152                 {.fd = 0, .events = POLLIN | POLLERR | POLLHUP},
153                 {.fd = s, .events = POLLIN | POLLERR | POLLHUP},
154         };
155
156         char buf[102400];
157         struct timeval timeout = utcp_timeout(u);
158
159         while(!connected || utcp_is_active(u)) {
160                 size_t max = c ? utcp_get_sndbuf_free(c) : 0;
161                 if(max > sizeof buf)
162                         max = sizeof buf;
163
164                 int timeout_ms = timeout.tv_sec * 1000 + timeout.tv_usec / 1000 + 1;
165
166                 debug("polling, dir = %d, timeout = %d\n", dir, timeout_ms);
167                 if((dir & DIR_READ) && max)
168                         poll(fds, 2, timeout_ms);
169                 else
170                         poll(fds + 1, 1, timeout_ms);
171
172                 if(fds[0].revents) {
173                         fds[0].revents = 0;
174                         debug("stdin\n");
175                         ssize_t len = read(0, buf, max);
176                         if(len <= 0) {
177                                 fds[0].fd = -1;
178                                 dir &= ~DIR_READ;
179                                 if(c)
180                                         utcp_shutdown(c, SHUT_WR);
181                                 if(len == -1)
182                                         break;
183                                 else
184                                         continue;
185                         }
186                         if(c) {
187                                 ssize_t sent = utcp_send(c, buf, len);
188                                 if(sent != len)
189                                         debug("Short send: %zd != %zd\n", sent, len);
190                         }
191                 }
192
193                 if(fds[1].revents) {
194                         fds[1].revents = 0;
195                         debug("netin\n");
196                         struct sockaddr_storage ss;
197                         socklen_t sl = sizeof ss;
198                         int len = recvfrom(s, buf, sizeof buf, MSG_DONTWAIT, (struct sockaddr *)&ss, &sl);
199                         if(len <= 0) {
200                                 debug("Error receiving UDP packet: %s\n", strerror(errno));
201                                 break;
202                         }
203                         if(!connected)
204                                 if(!connect(s, (struct sockaddr *)&ss, sl))
205                                         connected = true;
206                         inpktno++;
207                         if(inpktno >= dropto || inpktno < dropfrom || drand48() >= dropin) {
208                                 total_in += len;
209                                 utcp_recv(u, buf, len);
210                         }
211                 }
212
213                 timeout = utcp_timeout(u);
214         };
215
216         utcp_close(c);
217         utcp_exit(u);
218         free(reorder_data);
219
220         debug("Total bytes in: %ld, out: %ld\n", total_in, total_out);
221
222         return 0;
223 }