esp-idf/examples/protocols/sockets/udp_server/main/udp_server.c

138 lines
4.7 KiB
C

/* BSD Socket API Example
This example code is in the Public Domain (or CC0 licensed, at your option.)
Unless required by applicable law or agreed to in writing, this
software is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
CONDITIONS OF ANY KIND, either express or implied.
*/
#include <string.h>
#include <sys/param.h>
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "esp_system.h"
#include "esp_wifi.h"
#include "esp_event.h"
#include "esp_log.h"
#include "nvs_flash.h"
#include "esp_netif.h"
#include "protocol_examples_common.h"
#include "lwip/err.h"
#include "lwip/sockets.h"
#include "lwip/sys.h"
#include <lwip/netdb.h>
#define PORT CONFIG_EXAMPLE_PORT
static const char *TAG = "example";
static void udp_server_task(void *pvParameters)
{
char rx_buffer[128];
char addr_str[128];
int addr_family = (int)pvParameters;
int ip_protocol = 0;
struct sockaddr_in6 dest_addr;
while (1) {
if (addr_family == AF_INET) {
struct sockaddr_in *dest_addr_ip4 = (struct sockaddr_in *)&dest_addr;
dest_addr_ip4->sin_addr.s_addr = htonl(INADDR_ANY);
dest_addr_ip4->sin_family = AF_INET;
dest_addr_ip4->sin_port = htons(PORT);
ip_protocol = IPPROTO_IP;
} else if (addr_family == AF_INET6) {
bzero(&dest_addr.sin6_addr.un, sizeof(dest_addr.sin6_addr.un));
dest_addr.sin6_family = AF_INET6;
dest_addr.sin6_port = htons(PORT);
ip_protocol = IPPROTO_IPV6;
}
int sock = socket(addr_family, SOCK_DGRAM, ip_protocol);
if (sock < 0) {
ESP_LOGE(TAG, "Unable to create socket: errno %d", errno);
break;
}
ESP_LOGI(TAG, "Socket created");
#if defined(CONFIG_EXAMPLE_IPV4) && defined(CONFIG_EXAMPLE_IPV6)
if (addr_family == AF_INET6) {
// Note that by default IPV6 binds to both protocols, it is must be disabled
// if both protocols used at the same time (used in CI)
int opt = 1;
setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof(opt));
setsockopt(sock, IPPROTO_IPV6, IPV6_V6ONLY, &opt, sizeof(opt));
}
#endif
int err = bind(sock, (struct sockaddr *)&dest_addr, sizeof(dest_addr));
if (err < 0) {
ESP_LOGE(TAG, "Socket unable to bind: errno %d", errno);
}
ESP_LOGI(TAG, "Socket bound, port %d", PORT);
while (1) {
ESP_LOGI(TAG, "Waiting for data");
struct sockaddr_storage source_addr; // Large enough for both IPv4 or IPv6
socklen_t socklen = sizeof(source_addr);
int len = recvfrom(sock, rx_buffer, sizeof(rx_buffer) - 1, 0, (struct sockaddr *)&source_addr, &socklen);
// Error occurred during receiving
if (len < 0) {
ESP_LOGE(TAG, "recvfrom failed: errno %d", errno);
break;
}
// Data received
else {
// Get the sender's ip address as string
if (source_addr.ss_family == PF_INET) {
inet_ntoa_r(((struct sockaddr_in *)&source_addr)->sin_addr, addr_str, sizeof(addr_str) - 1);
} else if (source_addr.ss_family == PF_INET6) {
inet6_ntoa_r(((struct sockaddr_in6 *)&source_addr)->sin6_addr, addr_str, sizeof(addr_str) - 1);
}
rx_buffer[len] = 0; // Null-terminate whatever we received and treat like a string...
ESP_LOGI(TAG, "Received %d bytes from %s:", len, addr_str);
ESP_LOGI(TAG, "%s", rx_buffer);
int err = sendto(sock, rx_buffer, len, 0, (struct sockaddr *)&source_addr, sizeof(source_addr));
if (err < 0) {
ESP_LOGE(TAG, "Error occurred during sending: errno %d", errno);
break;
}
}
}
if (sock != -1) {
ESP_LOGE(TAG, "Shutting down socket and restarting...");
shutdown(sock, 0);
close(sock);
}
}
vTaskDelete(NULL);
}
void app_main(void)
{
ESP_ERROR_CHECK(nvs_flash_init());
ESP_ERROR_CHECK(esp_netif_init());
ESP_ERROR_CHECK(esp_event_loop_create_default());
/* This helper function configures Wi-Fi or Ethernet, as selected in menuconfig.
* Read "Establishing Wi-Fi or Ethernet Connection" section in
* examples/protocols/README.md for more information about this function.
*/
ESP_ERROR_CHECK(example_connect());
#ifdef CONFIG_EXAMPLE_IPV4
xTaskCreate(udp_server_task, "udp_server", 4096, (void*)AF_INET, 5, NULL);
#endif
#ifdef CONFIG_EXAMPLE_IPV6
xTaskCreate(udp_server_task, "udp_server", 4096, (void*)AF_INET6, 5, NULL);
#endif
}