fix sender udp packet drop

Author: netham45

main/scream_sender.c

@@ -13,6 +13,7 @@
 #include <lwip/netdb.h>
 #include <string.h>
 #include <math.h>
+#include "esp_rom_sys.h" // For ets_delay_us
 
 #define TAG "scream_sender"
 
@@ -22,6 +23,11 @@ static const char header[] = {1, 16, 2, 0, 0};
 #define CHUNK_SIZE 1152
 #define PACKET_SIZE (CHUNK_SIZE + HEADER_SIZE)
 
+// Socket options
+#define UDP_TX_BUFFER_SIZE (1024 * 32)
+#define UDP_SEND_TIMEOUT_MS 10
+#define MAX_SEND_RETRIES 3
+
 // State variables
 static bool s_is_sender_initialized = false;
 static bool s_is_sender_running = false;
@@ -32,7 +38,7 @@ static struct sockaddr_in s_dest_addr;
 
 // Buffer for audio data
 static char s_data_out[PACKET_SIZE];
-static char s_data_in[CHUNK_SIZE * 10];
+static char s_data_in[CHUNK_SIZE * 16]; // Increased buffer size
 static int s_data_in_head = 0;
 
 // UAC callbacks
@@ -48,7 +54,27 @@ static esp_err_t uac_device_output_cb(uint8_t *buf, size_t len, void *arg)
  // Process the data in chunks
  while (s_data_in_head >= CHUNK_SIZE) {
  memcpy(s_data_out + HEADER_SIZE, s_data_in, CHUNK_SIZE);
- sendto(s_sock, s_data_out, PACKET_SIZE, 0, (struct sockaddr *)&s_dest_addr, sizeof(s_dest_addr));
+ 
+ // Send with retry logic
+ int sent = -1;
+ int retry_count = 0;
+ 
+ while (sent < 0 && retry_count < MAX_SEND_RETRIES) {
+ sent = sendto(s_sock, s_data_out, PACKET_SIZE, 0, 
+ (struct sockaddr *)&s_dest_addr, sizeof(s_dest_addr));
+ 
+ if (sent < 0) {
+ ESP_LOGW(TAG, "Failed to send UDP packet: errno %d, retry %d", 
+ errno, retry_count + 1);
+ retry_count++;
+ 
+ // Small delay before retry (500 microseconds)
+ esp_rom_delay_us(500);
+ } else if (sent != PACKET_SIZE) {
+ ESP_LOGW(TAG, "Incomplete UDP packet sent: %d of %d bytes", 
+ sent, PACKET_SIZE);
+ }
+ }
 
  // Move remaining data to the beginning of the buffer
  s_data_in_head -= CHUNK_SIZE;
@@ -104,6 +130,32 @@ esp_err_t scream_sender_init(void)
  return ESP_FAIL;
  }
 
+ // Configure socket options for better reliability
+ int opt_val;
+ 
+ // Increase send buffer size
+ opt_val = UDP_TX_BUFFER_SIZE;
+ if (setsockopt(s_sock, SOL_SOCKET, SO_SNDBUF, &opt_val, sizeof(opt_val)) < 0) {
+ ESP_LOGW(TAG, "Failed to set SO_SNDBUF: errno %d", errno);
+ }
+ 
+ // Set timeout to prevent blocking too long on send
+ struct timeval timeout;
+ timeout.tv_sec = 0;
+ timeout.tv_usec = UDP_SEND_TIMEOUT_MS * 1000;
+ if (setsockopt(s_sock, SOL_SOCKET, SO_SNDTIMEO, &timeout, sizeof(timeout)) < 0) {
+ ESP_LOGW(TAG, "Failed to set SO_SNDTIMEO: errno %d", errno);
+ }
+ 
+ // Set QoS priority for audio traffic
+ #if defined(IP_TOS) && defined(IPTOS_DSCP_EF)
+ // Use Expedited Forwarding (EF) for real-time audio
+ opt_val = IPTOS_DSCP_EF;
+ if (setsockopt(s_sock, IPPROTO_IP, IP_TOS, &opt_val, sizeof(opt_val)) < 0) {
+ ESP_LOGW(TAG, "Failed to set IP_TOS: errno %d", errno);
+ }
+ #endif
+ 
  // Initialize the destination address from settings
  app_config_t *config = config_manager_get_config();
  memset(&s_dest_addr, 0, sizeof(s_dest_addr));
@@ -213,4 +265,4 @@ esp_err_t scream_sender_update_destination(void)
 
  return ESP_OK;
 }
-#endif
+#endif