From ce72d3d14d7c5f24fa4c9de3a9bfffe105e4588e Mon Sep 17 00:00:00 2001
From: Gerhard Hoffmann <g.hoffmann@atb-online.eu>
Date: Mon, 7 Aug 2023 13:50:59 +0200
Subject: [PATCH] For the error EWOULDBLOCK try again 10 times until quitting.

---
 ismas/ismas_client.cpp | 16 +++++++++++++---
 1 file changed, 13 insertions(+), 3 deletions(-)

diff --git a/ismas/ismas_client.cpp b/ismas/ismas_client.cpp
index a842180..2ffa602 100644
--- a/ismas/ismas_client.cpp
+++ b/ismas/ismas_client.cpp
@@ -148,6 +148,7 @@ IsmasClient::sendRequestReceiveResponse(int port, QString const &request) {
     int const bytesToWrite = strlen(request.toStdString().c_str());
     strncpy(buf, request.toStdString().c_str(), sizeof(buf)-1);
 
+    int loop = 0;
     int bytesWritten = 0;
     while (bytesWritten < bytesToWrite) {
         int n = ::sendto(sockfd, buf+bytesWritten, bytesToWrite-bytesWritten, 0, NULL, 0);
@@ -155,14 +156,18 @@ IsmasClient::sendRequestReceiveResponse(int port, QString const &request) {
             bytesWritten += n;
         } else {
             if (errno == EWOULDBLOCK) {
+                if (++loop < 10) {
+                    QThread::msleep(500);
+                    continue;
+                }
                 printErrorMessage(port, clientIP, clientPort,
-                    QString("TIMEOUT  (") + strerror(errno) + ")");
+                    QString("WRITE TIMEOUT %1(").arg(loop) + strerror(errno) + ")");
                 ::close(sockfd);
                 return std::nullopt;
             } else
             if (errno == EINTR) {
                 printErrorMessage(port, clientIP, clientPort,
-                    QString("INTERRUPTED BY SIGNAL (1) (") + strerror(errno) + ")");
+                    QString("WRITE INTERRUPTED BY SIGNAL (1) (") + strerror(errno) + ")");
                 continue;
             }
         }
@@ -177,6 +182,7 @@ IsmasClient::sendRequestReceiveResponse(int port, QString const &request) {
 
     printInfoMessage(port, clientIP, clientPort, QString("MESSAGE SENT ") + buf);
 
+    loop = 0;
     bzero(buf, sizeof(buf));
     int bytesToRead = sizeof(buf)-1;
     int bytesRead = 0;
@@ -196,8 +202,12 @@ IsmasClient::sendRequestReceiveResponse(int port, QString const &request) {
         } else
         if (n < 0) {
             if (errno == EWOULDBLOCK) {
+                if (++loop < 10) {
+                    QThread::msleep(500);
+                    continue;
+                }
                 printErrorMessage(port, clientIP, clientPort,
-                        QString("TIMEOUT  (") + strerror(errno) + ")");
+                        QString("READ TIMEOUT %1(").arg(loop) + strerror(errno) + ")");
                 ::close(sockfd);
                 return std::nullopt;
             }