From: Marcin Siodelski <marcin@isc.org>
Date: Wed, 11 Mar 2015 19:20:09 +0000 (+0100)
Subject: [3673] Updated comments about the max timestamp for the MySQL and PgSQL.
X-Git-Tag: trac3764_base~16^2~2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f48f9ebae5a5a72e7f0296cf1c6ea8c22d1d26ad;p=thirdparty%2Fkea.git

[3673] Updated comments about the max timestamp for the MySQL and PgSQL.
---

diff --git a/src/lib/dhcpsrv/mysql_lease_mgr.cc b/src/lib/dhcpsrv/mysql_lease_mgr.cc
index 45b42460b0..34f91bdf01 100644
--- a/src/lib/dhcpsrv/mysql_lease_mgr.cc
+++ b/src/lib/dhcpsrv/mysql_lease_mgr.cc
@@ -1287,7 +1287,8 @@ MySqlLeaseMgr::convertToDatabaseTime(const time_t cltt,
     int64_t expire_time_64 = static_cast<int64_t>(cltt) +
         static_cast<int64_t>(valid_lifetime);
 
-    // Prevent too large value.
+    // Even on 64-bit systems MySQL doesn't seem to accept the timestamps
+    // beyond the max value of int32_t.
     if (expire_time_64 > LeaseMgr::MAX_DB_TIME) {
         isc_throw(BadValue, "Time value is too large: " << expire_time_64);
     }
diff --git a/src/lib/dhcpsrv/pgsql_lease_mgr.cc b/src/lib/dhcpsrv/pgsql_lease_mgr.cc
index dba5d34ac1..0bd20966c0 100644
--- a/src/lib/dhcpsrv/pgsql_lease_mgr.cc
+++ b/src/lib/dhcpsrv/pgsql_lease_mgr.cc
@@ -315,10 +315,10 @@ public:
         int64_t expire_time_64 = static_cast<int64_t>(cltt) +
             static_cast<int64_t>(valid_lifetime);
 
-        // PostgreSQL does funny things with time if you get past Y2038.  It
-        // will accept the values (unlike MySQL which throws) but it
-        // stops correctly adjusting to local time when reading them back
-        // out. So lets disallow it here.
+        // On 32-bit systems the time_t is implemented as the int32_t value.
+        // We want to detect overflows beyond maximum int32_t value here
+        // to avoid the overflow in the PostgreSQL database. The PostgreSQL
+        // doesn't catch those overflows on its own.
         if (expire_time_64 > LeaseMgr::MAX_DB_TIME) {
             isc_throw(isc::BadValue, "Time value is too large: " << expire_time_64);
         }