From a1fc21dfe1fa021d705f65ef2253d6e19a54be7e Mon Sep 17 00:00:00 2001
From: Pascal Serrarens <pse@pale.blue>
Date: Tue, 8 Apr 2025 12:48:52 +0200
Subject: [PATCH] Receiving no longer crashes

---
 EspIdf/EspIdfParticipant.cpp    | 38 ++++++++++++++++++++-------------
 EspIdf/EspIdfParticipant.h      |  2 +-
 Participants/ParticipantUDP.cpp |  1 +
 3 files changed, 25 insertions(+), 16 deletions(-)

diff --git a/EspIdf/EspIdfParticipant.cpp b/EspIdf/EspIdfParticipant.cpp
index 4831d7d..c8188a5 100644
--- a/EspIdf/EspIdfParticipant.cpp
+++ b/EspIdf/EspIdfParticipant.cpp
@@ -9,6 +9,7 @@ void ParticipantUDP::Setup(int localPort,
                              const char* remoteIpAddress,
                              int remotePort) {
 #if defined(IDF_VER)
+std::cout << "Set up UDP\n";
   GetBroadcastAddress();
 
   wifi_ap_record_t ap_info;
@@ -19,8 +20,8 @@ void ParticipantUDP::Setup(int localPort,
   }
 
   // Create a UDP socket
-  sockfd = socket(AF_INET, SOCK_DGRAM, 0);
-  if (sockfd < 0) {
+  this->sockfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
+  if (this->sockfd < 0) {
     std::cout << "Unable to create UDP socket: errno " << errno << "\n";
     vTaskDelete(NULL);
     return;
@@ -36,7 +37,7 @@ void ParticipantUDP::Setup(int localPort,
 
       
   // Bind the socket to the address and port
-  if (bind(sockfd, (struct sockaddr*)&local_addr, sizeof(local_addr)) < 0) {
+  if (bind(this->sockfd, (struct sockaddr*)&local_addr, sizeof(local_addr)) < 0) {
     std::cout << "Unable to bind UDP socket: errno " << errno << "\n";
     close(sockfd);
     vTaskDelete(NULL);
@@ -79,39 +80,46 @@ void ParticipantUDP::GetBroadcastAddress() {
 
 void ParticipantUDP::Receive() {
 #if defined(IDF_VER)
-  struct pollfd fds;
-  fds.fd = sockfd;
-  fds.events = POLLIN;  // We're looking for data available to read
+  struct pollfd fds[1];
+  fds[0].fd = sockfd;
+  fds[0].events = POLLIN;  // We're looking for data available to read
 
   // Use poll() with a timeout of 0 to return immediately
-  int ret = poll(&fds, 1, 0);
+  int ret = poll(fds, 1, 0);
   if (ret == -1) {
     std::cout << "poll() error\n";
     return;
   }
-  socklen_t addr_len = sizeof(this->src_addr);
+  
+  //char buffer[1024];
+  struct sockaddr_in source_addr;
+
+  socklen_t addr_len = sizeof(source_addr);
   char sender_ipAddress[INET_ADDRSTRLEN];
 
-  while (ret > 0 && fds.revents & POLLIN) {
+  while (ret > 0 && fds[0].revents & POLLIN) {
     int packetSize = recvfrom(this->sockfd, buffer, sizeof(buffer) - 1, 0,
-                              (struct sockaddr*)&this->src_addr, &addr_len);
+                              (struct sockaddr*)&source_addr, &addr_len);
     if (packetSize < 0) {
       std::cout << "recvfrom() error\n";
       return;
+    } else if (packetSize == 0) {
+      break;
     }
 
-    std::cout << "receiving " << packetSize << " bytes\n";
-    // inet_ntoa_r(this->src_addr.sin_addr, sender_ipAddress, INET_ADDRSTRLEN);
-    // unsigned int sender_port = ntohs(this->src_addr.sin_port);
+    std::cout << "receiving " << packetSize << " bytes, msgId " << (int)this->buffer[0] << "\n";
+    inet_ntoa_r(source_addr.sin_addr, sender_ipAddress, INET_ADDRSTRLEN);
+    unsigned int sender_port = ntohs(source_addr.sin_port);
 
-    // ReceiveData(packetSize, sender_ipAddress, sender_port);
+    ReceiveData(packetSize, sender_ipAddress, sender_port);
 
-    int ret = poll(&fds, 1, 0);
+    ret = poll(fds, 1, 0);
     if (ret == -1) {
       std::cout << "poll() error\n";
       return;
     }
   }
+  //std::cout << "no more messages\n";
 
 #endif // IDF_VER
 }
diff --git a/EspIdf/EspIdfParticipant.h b/EspIdf/EspIdfParticipant.h
index fea444f..1e80f0e 100644
--- a/EspIdf/EspIdfParticipant.h
+++ b/EspIdf/EspIdfParticipant.h
@@ -20,7 +20,7 @@ class ParticipantUDP : public RoboidControl::ParticipantUDP {
 
   int sockfd;
   struct sockaddr_in dest_addr;
-  struct sockaddr_in src_addr;
+  //struct sockaddr_in src_addr;
 
   void GetBroadcastAddress();
 };
diff --git a/Participants/ParticipantUDP.cpp b/Participants/ParticipantUDP.cpp
index a443002..08270cf 100644
--- a/Participants/ParticipantUDP.cpp
+++ b/Participants/ParticipantUDP.cpp
@@ -98,6 +98,7 @@ void ParticipantUDP::Update(unsigned long currentTimeMs) {
 
       this->nextPublishMe = currentTimeMs + this->publishInterval;
     }
+    
     this->ReceiveUDP();
   }