From 65aacab48ff91de2704971d7e3d9c96837a365f1 Mon Sep 17 00:00:00 2001
From: ketmar <ketmar@ketmar.no-ip.org>
Date: Wed, 5 Jun 2024 07:02:52 +0000
Subject: [PATCH] backend/net: try to prevent hangup on conntection/read
 failure

FossilOrigin-Name: 6f86b22a2054e73a43b36547d92f1e6489413460170e50affecae5cd60e5cfb0
---
 chibackend/net/linesocket.d | 21 ++++++++++++++++-----
 1 file changed, 16 insertions(+), 5 deletions(-)

diff --git a/chibackend/net/linesocket.d b/chibackend/net/linesocket.d
index 8e39396..5526ca6 100644
--- a/chibackend/net/linesocket.d
+++ b/chibackend/net/linesocket.d
@@ -51,7 +51,7 @@ private:
     import core.stdc.stdlib : realloc;
     enum delta = 8192;
     auto nlen = rdbufsize+delta;
-    if (nlen >= 2*1024*1024) { freeRdBuf(); throw new Exception("line too long"); }
+    if (nlen >= 65536) { freeRdBuf(); throw new Exception("line too long"); }
     auto nb = cast(char*)realloc(cast(void*)rdbufp, nlen);
     if (nb is null) { freeRdBuf(); import core.exception : onOutOfMemoryErrorNoGC; onOutOfMemoryErrorNoGC(); }
     rdbufp = cast(usize)nb;
@@ -142,6 +142,7 @@ public:
     if (vdata.length == 0) return;
     //auto dataanchor = data; // 'cause we may get data which requires pointer to head
     const(char)[] data = cast(const(char)[])vdata; // arg is not modified, and properly anchored
+    int againsLeft = 6;
     for (;;) {
       static if (full) {
         if (data.length <= 1) break;
@@ -151,7 +152,10 @@ public:
         auto sd = sk.send(data, cast(SocketFlags)(MSG_NOSIGNAL|0x8000/*MSG_MORE*/));
       }
       if (sd <= 0) {
-        if (isErrorAgain(sd)) continue;
+        if (isErrorAgain(sd)) {
+          againsLeft -= 1;
+          if (againsLeft != 0) continue;
+        }
         abort(doshutdown:false);
         import std.conv : to;
         throw new Exception("send error ("~sd.to!string~")");
@@ -161,7 +165,10 @@ public:
     while (data.length) {
       auto sd = sk.send(data, cast(SocketFlags)(MSG_NOSIGNAL));
       if (sd <= 0) {
-        if (isErrorAgain(sd)) continue;
+        if (isErrorAgain(sd)) {
+          againsLeft -= 1;
+          if (againsLeft != 0) continue;
+        }
         abort(doshutdown:false);
         import std.conv : to;
         throw new Exception("send error ("~sd.to!string~")");
@@ -278,6 +285,7 @@ public:
       }
     }
     // no buffered line, get more data
+    int againsLeft = 6;
     for (;;) {
       assert(rdbufused <= rdbufsize);
       if (rdbufused >= rdbufsize) growRdBuf();
@@ -288,8 +296,11 @@ public:
         abort(doshutdown:false);
         throw new Exception("read error (connection closed)");
       }
-      if (rc <= 0) {
-        if (isErrorAgain(rc)) continue;
+      if (rc < 0) {
+        if (isErrorAgain(rc)) {
+          againsLeft -= 1;
+          if (againsLeft != 0) continue;
+        }
         import std.conv : to;
         abort(doshutdown:false);
         throw new Exception("read error ("~rc.to!string~")");
-- 
2.11.4.GIT