1 files changed, 105 insertions, 0 deletions
diff --git a/src/mongo/bson/optime.cpp b/src/mongo/bson/optime.cpp
new file mode 100644
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+++ b/src/mongo/bson/optime.cpp
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+/*    Copyright 2009 10gen Inc.
+ *
+ *    Licensed under the Apache License, Version 2.0 (the "License");
+ *    you may not use this file except in compliance with the License.
+ *    You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *    Unless required by applicable law or agreed to in writing, software
+ *    distributed under the License is distributed on an "AS IS" BASIS,
+ *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *    See the License for the specific language governing permissions and
+ *    limitations under the License.
+ */
+
+#include "mongo/bson/optime.h"
+
+#include <iostream>
+#include <limits>
+#include <ctime>
+
+#include "mongo/bson/inline_decls.h"
+#include "mongo/util/debug_util.h"
+#include "mongo/util/log.h"
+#include "mongo/util/startup_test.h"
+
+namespace mongo {
+
+    OpTime OpTime::last(0, 0);
+    boost::condition OpTime::notifier;
+    mongo::mutex OpTime::m("optime");
+
+    NOINLINE_DECL OpTime OpTime::skewed() {
+        bool toLog = false;
+        ONCE toLog = true;
+        RARELY toLog = true;
+        last.i++;
+        if ( last.i & 0x80000000 )
+            toLog = true;
+        if ( toLog ) {
+            log() << "clock skew detected  prev: " << last.secs << " now: " << (unsigned) time(0) 
+                  << std::endl;
+        }
+        if ( last.i & 0x80000000 ) {
+            log() << "error large clock skew detected, shutting down" << std::endl;
+            throw ClockSkewException();
+        }
+        return last;
+    }
+
+    /*static*/ OpTime OpTime::_now() {
+        OpTime result;
+        unsigned t = (unsigned) time(0);
+        if ( last.secs == t ) {
+            last.i++;
+            result = last;
+        }
+        else if ( t < last.secs ) {
+            result = skewed(); // separate function to keep out of the hot code path
+        }
+        else { 
+            last = OpTime(t, 1);
+            result = last;
+        }
+        notifier.notify_all();
+        return last;
+    }
+
+    OpTime OpTime::now(const mongo::mutex::scoped_lock&) {
+        return _now();
+    }
+
+    OpTime OpTime::getLast(const mongo::mutex::scoped_lock&) {
+        return last;
+    }
+
+    OpTime OpTime::max() {
+        unsigned int t = static_cast<unsigned int>(std::numeric_limits<int32_t>::max());
+        unsigned int i = std::numeric_limits<uint32_t>::max();
+        return OpTime(t, i);
+    }
+
+    void OpTime::waitForDifferent(unsigned millis){
+        mutex::scoped_lock lk(m);
+        while (*this == last) {
+            if (!notifier.timed_wait(lk.boost(), boost::posix_time::milliseconds(millis)))
+                return; // timed out
+        }
+    }
+
+    struct TestOpTime : public StartupTest {
+        void run() {
+            OpTime t;
+            for ( int i = 0; i < 10; i++ ) {
+                OpTime s = OpTime::_now();
+                verify( s != t );
+                t = s;
+            }
+            OpTime q = t;
+            verify( q == t );
+            verify( !(q != t) );
+        }
+    } testoptime;
+
+}