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  1. Undertow
  2. UNDERTOW-1501

Wait-indefinitely hang bug in WebSocket session container shutdown code.

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      There is a wait-indefinitely bug in the WebSocket session container where `wait(0)` may be called due to a split condition/use problem. This could cause a thread to hang indefinitely if `current time < end` is checked with 1 tick to go, and `wait` is called after the next clock tick. If the thread blocks between calls, it could also spuriously throw an IllegalArgumentException due to a negative argument.

      Current code:

                  long end = System.currentTimeMillis() + timeout;
            try {
                while (System.currentTimeMillis() < end && !openSessions.isEmpty()) {
                    wait(end - System.currentTimeMillis());
                }

      Correct code:

                  long cur,end = System.currentTimeMillis() + timeout;
            try {
                while ((cur=System.currentTimeMillis()) < end && !openSessions.isEmpty()) {
                    wait(end - cur);
                }

              rhn-cservice-bbaranow Bartosz Baranowski
              lawrence-dol L. Cornelius Dol
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                Created:
                Updated:
                Resolved: