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Fix TorControlSocket shutdown hang by adding timeout #256

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Fix TorControlSocket shutdown hang by adding timeout #256

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afb0843
Fix TorControlSocket shutdown hang by adding timeout
MHT417 Jan 30, 2026
a36fa8f
Variable typo
MHT417 Jan 30, 2026
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18 changes: 15 additions & 3 deletions src/tor/TorControl.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -535,16 +535,28 @@ void TorControl::shutdown()

void TorControl::shutdownSync()
{

if (!hasOwnership()) {
RsWarn() << "torctrl: Ignoring shutdown command for a tor instance I don't own";
return;
}

shutdown();
while (mSocket->moretowrite(0))

// Add timeout to prevent infinite wait
int timeout_cnt = 0;
const int MAX_WAIT_ITERATIONS = 50; // 5 seconds max (50 * 100ms)

while (mSocket->moretowrite(0) && timeout_cnt < MAX_WAIT_ITERATIONS) {
std::this_thread::sleep_for(std::chrono::milliseconds(100));

timeout_cnt++;
}

if (timeout_cnt >= MAX_WAIT_ITERATIONS) {
RsWarn() << "torctrl: Timeout waiting for socket to flush during shutdown, forcing close";
}

mSocket->close();

}

void TorControl::statusEvent(int /* code */, const ByteArray &data)
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19 changes: 14 additions & 5 deletions src/tor/TorControlSocket.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -126,6 +126,10 @@ ByteArray TorControlSocket::readline(int s)

void TorControlSocket::process()
{

int empty_line_cnt = 0;
const int MAX_EMPTY_RETRIES = 20;

for (;;) {
if (!moretoread(0))
return;
Expand All @@ -134,10 +138,15 @@ void TorControlSocket::process()

if(line.empty()) // This happens when the incoming buffer isn't empty yet doesn't have a full line already.
{
if (++empty_line_cnt > MAX_EMPTY_RETRIES || shouldStop()) {
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@csoler csoler Feb 1, 2026

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What happens here is the network is somehow stuck (due to some lag)? The TorControlSocket process will stop. I'm not sure you want that, unless there is a built-in mechanism to get it to restart when needed.

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@MHT417 MHT417 Feb 1, 2026

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It gets stuck when quitting a tor node, or occasionally even without quitting. the thread will just wait forever unless a timeout exists. it was tested again on a tor node after applying a timeout and the issue never occurred, RS will run without getting stuck

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@csoler csoler Feb 2, 2026

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Sorry I mispelled. I wanted to say "what happens IF the network is somehow stuck".

return; // Give up after timeout or stop request
}
std::this_thread::sleep_for(std::chrono::milliseconds(50));
continue;
}

empty_line_cnt = 0; // reset

if (!line.endsWith(ByteArray("\r\n"))) {
setError("Invalid control message syntax");
return;
Expand Down Expand Up @@ -225,12 +234,12 @@ void TorControlSocket::process()
int TorControlSocket::tick()
{
bool rw = RsTcpSocket::tick();

if(moretoread(0))
process();

if(!rw)
std::this_thread::sleep_for(std::chrono::milliseconds(1000)); // temporisation when nothing happens

return 0; // not sure about what we should return here.
std::this_thread::sleep_for(std::chrono::milliseconds(50)); // Much shorter sleep
return 0;
}