From 379a36f43d3f4db4afa5ad4fb6f79b89824c999c Mon Sep 17 00:00:00 2001 From: David Kalnischkies Date: Fri, 12 Aug 2016 10:02:28 +0200 Subject: ensure a good clock() value for usage and tests MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit We use clock() as a very cheap way of getting a "random" value, but the manpage warns that this could return -1, so we should be dealing with this. Additionally, e.g. on hurd-i386 the value increases only slowly – to slow for our fast running tests for randomness hence producing the same range in both samples, so we introduce a simple busy-wait loop (as clock is counting processor time used by the program) in the test which delays the second sample just enough making our randomness a bit more predictable. --- apt-pkg/contrib/srvrec.cc | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'apt-pkg/contrib') diff --git a/apt-pkg/contrib/srvrec.cc b/apt-pkg/contrib/srvrec.cc index be159bad9..327e59937 100644 --- a/apt-pkg/contrib/srvrec.cc +++ b/apt-pkg/contrib/srvrec.cc @@ -185,7 +185,7 @@ SrvRec PopFromSrvRecs(std::vector &Recs) [&I](SrvRec const &J) { return I->priority != J.priority; }); // clock seems random enough. - I += clock() % std::distance(I, J); + I += std::max(static_cast(0), clock()) % std::distance(I, J); SrvRec const selected = std::move(*I); Recs.erase(I); -- cgit v1.2.3