sdk-ameba-v4.0b_without_nda.../component/common/example/mcast/example_mcast.c
2017-10-15 14:36:37 +08:00

98 lines
2.8 KiB
C

#include "FreeRTOS.h"
#include "task.h"
#include <platform/platform_stdlib.h>
#include <lwip/sockets.h>
#include <lwip_netconf.h>
#include <lwip/netif.h>
extern struct netif xnetif[];
static void example_mcast_thread(void *param)
{
#if LWIP_IGMP
int err = 0;
int socket = -1;
char *group_ip = "224.0.0.251";
uint16_t port = 5353;
// Set NETIF_FLAG_IGMP flag for netif which should process IGMP messages
xnetif[0].flags |= NETIF_FLAG_IGMP;
if((socket = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
printf("ERROR: socket - AF_INET, SOCK_DGRAM\n");
err = -1;
}
// Add multicast group membership on this interface
if(err == 0) {
struct ip_mreq imr;
imr.imr_multiaddr.s_addr = inet_addr(group_ip);
imr.imr_interface.s_addr = INADDR_ANY;
err = setsockopt(socket, IPPROTO_IP, IP_ADD_MEMBERSHIP, &imr, sizeof(imr));
if(err < 0) printf("ERROR: setsockopt - IP_ADD_MEMBERSHIP\n");
}
// Specify outgoing interface too
if(err == 0) {
struct in_addr intfAddr;
intfAddr.s_addr = INADDR_ANY;
err = setsockopt(socket, IPPROTO_IP, IP_MULTICAST_IF, &intfAddr, sizeof(struct in_addr));
if(err < 0) printf("ERROR: setsockopt - IP_MULTICAST_IF\n");
}
// And start listening for packets
if(err == 0) {
struct sockaddr_in bindAddr;
bindAddr.sin_family = AF_INET;
bindAddr.sin_port = htons(port);
bindAddr.sin_addr.s_addr = INADDR_ANY;
err = bind(socket, (struct sockaddr *) &bindAddr, sizeof(bindAddr));
if(err < 0) printf("ERROR: bind\n");
}
if(err == 0) {
unsigned char packet[1024];
while(1) {
// Receive multicast
int packetLen;
struct sockaddr from;
struct sockaddr_in *from_sin = (struct sockaddr_in*) &from;
socklen_t fromLen = sizeof(from);
if((packetLen = recvfrom(socket, &packet, sizeof(packet), 0, &from, &fromLen)) >= 0) {
uint8_t *ip = (uint8_t *) &from_sin->sin_addr.s_addr;
uint16_t from_port = ntohs(from_sin->sin_port);
printf("recvfrom - %d bytes from %d.%d.%d.%d:%d\n", packetLen, ip[0], ip[1], ip[2], ip[3], from_port);
}
// Send multicast
if(packetLen > 0) {
int sendLen;
struct sockaddr to;
struct sockaddr_in *to_sin = (struct sockaddr_in*) &to;
to_sin->sin_family = AF_INET;
to_sin->sin_port = htons(port);
to_sin->sin_addr.s_addr = inet_addr(group_ip);
if((sendLen = sendto(socket, packet, packetLen, 0, &to, sizeof(struct sockaddr))) < 0)
printf("ERROR: sendto %s\n", group_ip);
else
printf("sendto - %d bytes to %s:%d\n", sendLen, group_ip, port);
}
}
}
else if(socket != -1) {
close(socket);
}
#else
printf("\nSHOULD ENABLE LWIP_IGMP\n");
#endif
vTaskDelete(NULL);
}
void example_mcast(void)
{
if(xTaskCreate(example_mcast_thread, ((const char*)"example_mcast_thread"), 2048, NULL, tskIDLE_PRIORITY + 1, NULL) != pdPASS)
printf("\n\r%s xTaskCreate(init_thread) failed", __FUNCTION__);
}