[fuzz] Avoid endless waiting in FuzzedSock::{Wait,WaitMany}

Currently, when the FuzzedDataProvider of a FuzzedSock runs out of data,
FuzzedSock::Wait and WaitMany will simulate endless waiting as the
requested events are never simulated as occured.

Fix this by simulating event occurence when ConsumeBool() returns false
(e.g. when the data provider runs out).

Co-authored-by: dergoegge <n.goeggi@gmail.com>

Author: marcofleon

src/test/fuzz/util/net.cpp

@@ -383,7 +383,10 @@ bool FuzzedSock::Wait(std::chrono::milliseconds timeout, Event requested, Event*
         return false;
     }
     if (occurred != nullptr) {
-        *occurred = m_fuzzed_data_provider.ConsumeBool() ? requested : 0;
+        // We simulate the requested event as occured when ConsumeBool()
+        // returns false. This avoids simulating endless waiting if the
+        // FuzzedDataProvider runs out of data.
+        *occurred = m_fuzzed_data_provider.ConsumeBool() ? 0 : requested;
     }
     return true;
 }
@@ -392,7 +395,10 @@ bool FuzzedSock::WaitMany(std::chrono::milliseconds timeout, EventsPerSock& even
 {
     for (auto& [sock, events] : events_per_sock) {
         (void)sock;
-        events.occurred = m_fuzzed_data_provider.ConsumeBool() ? events.requested : 0;
+        // We simulate the requested event as occured when ConsumeBool()
+        // returns false. This avoids simulating endless waiting if the
+        // FuzzedDataProvider runs out of data.
+        events.occurred = m_fuzzed_data_provider.ConsumeBool() ? 0 : events.requested;
     }
     return true;
 }