#include #include #include #include #include "evt_core.h" #include "net_tools.h" int on_udp(struct evt_core_ctx* ctx, struct evt_core_fdinfo* fdinfo) { char buffer[1500]; ssize_t nread, nwritten; struct sockaddr_in addr; socklen_t addrlen = sizeof(addr); nread = recvfrom(fdinfo->fd, buffer, sizeof(buffer), MSG_TRUNC, (struct sockaddr*)&addr, &addrlen); if (nread == -1 && errno == EAGAIN) return 1; // Read done if (nread <= 0 || nread > sizeof(buffer)) { fprintf(stderr, "Message is either truncated or an error occured. nread=%ld\n", nread); perror("read errno"); exit(EXIT_FAILURE); } nwritten = sendto(fdinfo->fd, buffer, nread, 0, (struct sockaddr*)&addr, addrlen); // @FIXME don't support EAGAIN on write. Could be intended, you don't think so? if (nwritten != nread) { fprintf(stderr, "Didn't write the same number of bytes as read. nread=%ld, nwritten=%ld\n", nread, nwritten); perror("write errno"); exit(EXIT_FAILURE); } return 0; } int main(int argc, char** argv) { setvbuf(stdout, NULL, _IONBF, 0); printf("~ udpecho ~\n"); int opt, udp_sock, verbose = 0; char *port = NULL; struct evt_core_ctx evts = {0}; // 1. Parse parameters while ((opt = getopt(argc, argv, "p:v")) != -1) { switch(opt) { case 'v': verbose++; break; case 'p': port = optarg; break; default: goto usage; } } // 2. Register category struct evt_core_cat udp_read = { .app_ctx = NULL, .free_app_ctx = NULL, .cb = on_udp, .err_cb = NULL, .name = "udp-read", .flags = EPOLLIN | EPOLLET, .socklist = NULL }; evt_core_init(&evts, verbose); evt_core_add_cat(&evts, &udp_read); // 3. Register UDP socket udp_sock = create_udp_server ("127.0.0.1", port); char url[1024]; struct evt_core_cat cat = {0}; struct evt_core_fdinfo fdinfo = {0}; fdinfo.cat = &cat; fdinfo.url = url; fdinfo.fd = udp_sock; sprintf(url, "udp:rw:127.0.0.1:%s", port); fdinfo.cat->name = "udp-read"; evt_core_add_fd(&evts, &fdinfo); // 4. Start main loop evt_core_loop (&evts); return 0; usage: fprintf(stderr, "Usage: %s -p [-v]\n", argv[0]); }