Revert "SERVER-34975 Treat an OID-embedded timestamp as unsigned."

This reverts commit a9deb701a7533b566a2eb703aff70bf2f03b147c.

3 files changed, 11 insertions, 6 deletions

diff --git a/src/mongo/bson/oid.cpp b/src/mongo/bson/oid.cpp
index ca9c6e558a9..26d90d97bad 100644
--- a/src/mongo/bson/oid.cpp
+++ b/src/mongo/bson/oid.cpp
@@ -162,6 +162,10 @@ void OID::init(Date_t date, bool max) {
     std::memcpy(_view().view(kInstanceUniqueOffset), &rest, kInstanceUniqueSize + kIncrementSize);
 }
 
+time_t OID::asTimeT() const {
+    return getTimestamp();
+}
+
 std::string OID::toString() const {
     return toHexLower(_data, kOIDSize);
 }
diff --git a/src/mongo/bson/oid.h b/src/mongo/bson/oid.h
index 7f4f31a4369..4474a12dbe2 100644
--- a/src/mongo/bson/oid.h
+++ b/src/mongo/bson/oid.h
@@ -176,8 +176,9 @@ public:
      */
     void initFromTermNumber(int64_t term);
 
+    time_t asTimeT() const;
     Date_t asDateT() const {
-        return Date_t::fromMillisSinceEpoch(getTimestamp() * 1000LL);
+        return Date_t::fromMillisSinceEpoch(asTimeT() * 1000LL);
     }
 
     // True iff the OID is not empty
@@ -197,8 +198,8 @@ public:
     static unsigned getMachineId();  // used by the 'features' command
     static void regenMachineId();
 
-    // Timestamp is a 4-byte positive integer so we use uint32_t
-    typedef uint32_t Timestamp;
+    // Timestamp is 4 bytes so we just use int32_t
+    typedef int32_t Timestamp;
 
     // Wrappers so we can return stuff by value.
     struct InstanceUnique {
diff --git a/src/mongo/bson/oid_test.cpp b/src/mongo/bson/oid_test.cpp
index 6d34d6a5808..8be156ae41d 100644
--- a/src/mongo/bson/oid_test.cpp
+++ b/src/mongo/bson/oid_test.cpp
@@ -109,7 +109,7 @@ TEST(Basic, Deserialize) {
         0xDEu,
         0xADu,
         0xBEu,
-        0xEFu,  // timestamp is 3735928559 (unsigned)
+        0xEFu,  // timestamp is -559038737 (signed)
         0x00u,
         0x00u,
         0x00u,
@@ -122,7 +122,7 @@ TEST(Basic, Deserialize) {
 
     OID o1 = OID::from(OIDbytes);
 
-    ASSERT_EQUALS(o1.getTimestamp(), 3735928559);
+    ASSERT_EQUALS(o1.getTimestamp(), -559038737);
     OID::InstanceUnique u = o1.getInstanceUnique();
     for (std::size_t i = 0; i < OID::kInstanceUniqueSize; ++i) {
         ASSERT_EQUALS(u.bytes[i], 0x00u);
@@ -158,7 +158,7 @@ TEST(Basic, FromTerm) {
     auto oidHead = oidStr.substr(0, 8);
     auto oidTail = oidStr.substr(oidStr.length() - 1);
 
-    ASSERT_EQUALS("ffffffff", oidHead);
+    ASSERT_EQUALS("7fffffff", oidHead);
     ASSERT_EQUALS(term, std::stoi(oidTail));
 }
 }