From: Nathan Bronson <ngbronson@fb.com>
Date: Fri, 19 Jul 2013 18:12:59 +0000 (-0700)
Subject: folly/MPMCQueue sizeGuess should return a signed int
X-Git-Tag: v0.22.0~922
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=ff1046b8a239d5f7e58e2756f6b7eb8ec830ff61;p=folly.git

folly/MPMCQueue sizeGuess should return a signed int

Summary:
Like size(), sizeGuess() is allowed to return a negative value,
so it should be ssize_t instead of uint64_t.

Test Plan: fbmake, wait for contbuild

Reviewed By: tudorb@fb.com

FB internal diff: D893075
---

diff --git a/folly/MPMCQueue.h b/folly/MPMCQueue.h
index 9fb7867f..58c1d3ce 100644
--- a/folly/MPMCQueue.h
+++ b/folly/MPMCQueue.h
@@ -196,7 +196,7 @@ class MPMCQueue : boost::noncopyable {
 
   /// Returns is a guess at size() for contexts that don't need a precise
   /// value, such as stats.
-  uint64_t sizeGuess() const noexcept {
+  ssize_t sizeGuess() const noexcept {
     return writeCount() - readCount();
   }