From: Alex Rousskov <rousskov@measurement-factory.com>
Date: Mon, 7 Jan 2013 17:14:28 +0000 (-0700)
Subject: Provide a safer version of a "is set" operator and
X-Git-Tag: SQUID_3_5_0_1~444^2~90
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=99b1961024b13dafe028f58d5e17b24bcafe5384;p=thirdparty%2Fsquid.git

Provide a safer version of a "is set" operator and
its explicitly named equivalent.
---

diff --git a/src/ipc/mem/Page.h b/src/ipc/mem/Page.h
index e7ff8c5667..0d2d481bb8 100644
--- a/src/ipc/mem/Page.h
+++ b/src/ipc/mem/Page.h
@@ -20,7 +20,12 @@ class PageId
 public:
     PageId(): pool(0), number(0), purpose(maxPurpose) {}
 
-    operator bool() const { return pool && number; }
+    /// true if and only if both critical components have been initialized
+    bool set() const { return pool && number; }
+
+    // safer than bool which would enable silent casts to int
+    typedef const uint32_t PageId::*SaferBool;
+    operator SaferBool() const { return set() ? &PageId::number : NULL; }
 
     uint32_t pool; ///< page pool ID within Squid
     // uint32_t segment; ///< memory segment ID within the pool; unused for now