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| #include <stdlib.h>
| #include <stdio.h>
| #include <string.h>
| #include <time.h>
|
| #include <nng/nng.h>
| #include <nng/protocol/reqrep0/rep.h>
| #include <nng/protocol/reqrep0/req.h>
|
| #define NODE0 "node0"
| #define NODE1 "node1"
| #define DATE "DATE"
|
| void
| fatal(const char *func, int rv)
| {
| fprintf(stderr, "%s: %s\n", func, nng_strerror(rv));
| exit(1);
| }
|
| char *
| date(void)
| {
| time_t now = time(&now);
| struct tm *info = localtime(&now);
| char *text = asctime(info);
| text[strlen(text)-1] = '\0'; // remove '\n'
| return (text);
| }
|
| int
| node0(const char *url)
| {
| nng_socket sock;
| int rv;
|
| if ((rv = nng_rep0_open(&sock)) != 0) {
| fatal("nng_rep0_open", rv);
| }
| if ((rv = nng_listen(sock, url, NULL, 0)) != 0) {
| fatal("nng_listen", rv);
| }
| for (;;) {
| char *buf = NULL;
| size_t sz;
| if ((rv = nng_recv(sock, &buf, &sz, NNG_FLAG_ALLOC)) != 0) {
| fatal("nng_recv", rv);
| }
| if ((sz == (strlen(DATE) + 1)) && (strcmp(DATE, buf) == 0)) {
| printf("NODE0: RECEIVED DATE REQUEST\n");
| char *d = date();
| printf("NODE0: SENDING DATE %s\n", d);
| if ((rv = nng_send(sock, d, strlen(d) + 1, 0)) != 0) {
| fatal("nng_send", rv);
| }
| }
| nng_free(buf, sz);
| }
| }
|
| int
| node1(const char *url)
| {
| nng_socket sock;
| int rv;
| size_t sz;
| char *buf = NULL;
|
| if ((rv = nng_req0_open(&sock)) != 0) {
| fatal("nng_socket", rv);
| }
| if ((rv = nng_dial(sock, url, NULL, 0)) != 0) {
| fatal("nng_dial", rv);
| }
| printf("NODE1: SENDING DATE REQUEST %s\n", DATE);
| if ((rv = nng_send(sock, DATE, strlen(DATE)+1, 0)) != 0) {
| fatal("nng_send", rv);
| }
| if ((rv = nng_recv(sock, &buf, &sz, NNG_FLAG_ALLOC)) != 0) {
| fatal("nng_recv", rv);
| }
| printf("NODE1: RECEIVED DATE %s\n", buf);
| nng_free(buf, sz);
| nng_close(sock);
| return (0);
| }
|
| int
| main(const int argc, const char **argv)
| {
| if ((argc > 1) && (strcmp(NODE0, argv[1]) == 0))
| return (node0(argv[2]));
|
| if ((argc > 1) && (strcmp(NODE1, argv[1]) == 0))
| return (node1(argv[2]));
|
| fprintf(stderr, "Usage: reqrep %s|%s <URL> ...\n", NODE0, NODE1);
| return (1);
| }
|
|
| ./reqrep node0 ipc:///tmp/reqrep.ipc & node0=$! && sleep 1
| ./reqrep node1 ipc:///tmp/reqrep.ipc
|
|
