OVMS3-idf/examples/protocols/sockets/udp_client/main/udp_client.c
David Cermak acf1478a51 socket-examples: IPv6 related update for examples to set correct scoped id
The scope id must be present when connecting to IPv6 Local Link
address.
2020-05-22 06:19:49 +00:00

126 lines
4 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 "freertos/event_groups.h"
#include "esp_system.h"
#include "esp_wifi.h"
#include "esp_event.h"
#include "esp_log.h"
#include "nvs_flash.h"
#include "tcpip_adapter.h"
#include "protocol_examples_common.h"
#include "lwip/err.h"
#include "lwip/sockets.h"
#include "lwip/sys.h"
#include <lwip/netdb.h>
#ifdef CONFIG_EXAMPLE_IPV4
#define HOST_IP_ADDR CONFIG_EXAMPLE_IPV4_ADDR
#else
#define HOST_IP_ADDR CONFIG_EXAMPLE_IPV6_ADDR
#endif
#define PORT CONFIG_EXAMPLE_PORT
static const char *TAG = "example";
static const char *payload = "Message from ESP32 ";
static void udp_client_task(void *pvParameters)
{
char rx_buffer[128];
char addr_str[128];
int addr_family;
int ip_protocol;
while (1) {
#ifdef CONFIG_EXAMPLE_IPV4
struct sockaddr_in dest_addr;
dest_addr.sin_addr.s_addr = inet_addr(HOST_IP_ADDR);
dest_addr.sin_family = AF_INET;
dest_addr.sin_port = htons(PORT);
addr_family = AF_INET;
ip_protocol = IPPROTO_IP;
inet_ntoa_r(dest_addr.sin_addr, addr_str, sizeof(addr_str) - 1);
#else // IPV6
struct sockaddr_in6 dest_addr = { 0 };
inet6_aton(HOST_IP_ADDR, &dest_addr.sin6_addr);
dest_addr.sin6_family = AF_INET6;
dest_addr.sin6_port = htons(PORT);
// Setting scope_id to the connecting interface for correct routing if IPv6 Local Link supplied
dest_addr.sin6_scope_id = esp_netif_get_netif_impl_index(EXAMPLE_INTERFACE);
addr_family = AF_INET6;
ip_protocol = IPPROTO_IPV6;
inet6_ntoa_r(dest_addr.sin6_addr, addr_str, sizeof(addr_str) - 1);
#endif
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, sending to %s:%d", HOST_IP_ADDR, PORT);
while (1) {
int err = sendto(sock, payload, strlen(payload), 0, (struct sockaddr *)&dest_addr, sizeof(dest_addr));
if (err < 0) {
ESP_LOGE(TAG, "Error occurred during sending: errno %d", errno);
break;
}
ESP_LOGI(TAG, "Message sent");
struct sockaddr_in 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 {
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);
}
vTaskDelay(2000 / portTICK_PERIOD_MS);
}
if (sock != -1) {
ESP_LOGE(TAG, "Shutting down socket and restarting...");
shutdown(sock, 0);
close(sock);
}
}
vTaskDelete(NULL);
}
void app_main()
{
ESP_ERROR_CHECK(nvs_flash_init());
tcpip_adapter_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());
xTaskCreate(udp_client_task, "udp_client", 4096, NULL, 5, NULL);
}