Blinker

limit maximum timeout for select()
Parent e2b53fb
Stefan Schuermans

Stefan Schuermans commited on 2018-09-02 10:43:07
Showing 2 changed files, with 11 additions and 2 deletions.

src/linux/Io.cpp
View file @ 7e05917
... ... 
@@ -21,6 +21,8 @@ namespace Blinker {
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  */
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 void Io::wait(Set &read, Set &write, const Time &timeout)
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 {
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+  static const Time maxTimeout(0.5); // maximum timeout for I/O wait
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+
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   // get maximum file descriptor, read set and write set
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   int max = 0;
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   fd_set fd_rd;
... ... 
@@ -40,10 +42,13 @@ void Io::wait(Set &read, Set &write, const Time &timeout)
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   // get timeout
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   struct timeval to;
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-  if (timeout < Time::zero) // don't use negaitve timeout
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+  if (timeout < Time::zero) { // don't use negative timeout
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     Time::zero.toTimeval(to);
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-  else
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+  } else if (timeout > maxTimeout) { // stay responsive -> no more than max
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+    maxTimeout.toTimeval(to);
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+  } else {
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     timeout.toTimeval(to);
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+  }
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   // wait for I/O event
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   fd_set fd_err;
src/windows/Io.cpp
View file @ 7e05917
... ... 
@@ -21,6 +21,8 @@ namespace Blinker {
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  */
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 void Io::wait(Set &read, Set &write, const Time &timeout)
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 {
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+  static const Time maxTimeout(0.5); // maximum timeout for I/O wait
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+
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   // get read set and write set, also count entries
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   unsigned int rds = 0;
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   fd_set fd_rd;
... ... 
@@ -54,6 +56,8 @@ void Io::wait(Set &read, Set &write, const Time &timeout)
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   struct timeval to;
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   if (timeout < Time::zero) { // don't use negative timeout
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     Time::zero.toTimeval(to);
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+  } else if (timeout > maxTimeout) { // stay responsive -> no more than max
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+    maxTimeout.toTimeval(to);
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   } else {
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     timeout.toTimeval(to);
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   }
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