SERVER-43964 UUID etc need not befriend IDL types

1 files changed, 10 insertions, 74 deletions

diff --git a/src/mongo/util/uuid.h b/src/mongo/util/uuid.h
index a5e259a3c9a..eade27480d6 100644
--- a/src/mongo/util/uuid.h
+++ b/src/mongo/util/uuid.h
@@ -40,83 +40,20 @@
 #include "mongo/bson/bsonmisc.h"
 #include "mongo/bson/bsonobj.h"
 #include "mongo/logv2/log_attr.h"
+#include "mongo/stdx/type_traits.h"
 
 namespace mongo {
 
-namespace repl {
-class CollectionInfo;
-class OplogEntryBase;
-class DurableReplOperation;
-class InitialSyncIdDocument;
-}  // namespace repl
-
-namespace idl {
-namespace import {
-class One_UUID;
-}  // namespace import
-}  // namespace idl
-
 /**
  * A UUID is a 128-bit unique identifier, per RFC 4122, v4, using
  * a secure random number generator.
  */
 class UUID {
-    using UUIDStorage = std::array<unsigned char, 16>;
-
-    // Make the IDL generated parser a friend
-    friend class ConfigsvrShardCollectionResponse;
-    friend class CommonReshardingMetadata;
-    friend class DonorAbortMigration;
-    friend class DonorStartMigration;
-    friend class DonorWaitForMigrationToCommit;
-    friend class DonorForgetMigration;
-    friend class DonorStateMachine;
-    friend class DatabaseVersion;
-    friend class DbCheckOplogCollection;
-    friend class EncryptionPlaceholder;
-    friend class ExternalKeysCollectionDocument;
-    friend class idl::import::One_UUID;
-    friend class IndexBuildEntry;
-    friend class KeyStoreRecord;
-    friend class ListCollectionsReplyInfo;
-    friend class LogicalSessionId;
-    friend class LogicalSessionToClient;
-    friend class LogicalSessionIdToClient;
-    friend class LogicalSessionFromClient;
-    friend class MigrationCoordinatorDocument;
-    friend class MigrationDestinationManager;
-    friend class MigrationRecipientCommonData;
-    friend class RangeDeletionTask;
-    friend class ResolvedKeyId;
-    friend class repl::CollectionInfo;
-    friend class repl::OplogEntryBase;
-    friend class repl::DurableReplOperation;
-    friend class repl::InitialSyncIdDocument;
-    friend class RecipientForgetMigration;
-    friend class RecipientSyncData;
-    friend class ReshardingDonorDocument;
-    friend class ReshardingSourceId;
-    friend class ResumeIndexInfo;
-    friend class ResumeTokenInternal;
-    friend class ShardCollectionTypeBase;
-    friend class ShardsvrCleanupReshardCollection;
-    friend class ShardsvrShardCollectionResponse;
-    friend class ShardsvrRenameCollection;
-    friend class TenantMigrationDonorDocument;
-    friend class TenantMigrationRecipientDocument;
-    friend class TestReshardCloneCollection;
-    friend class TypeCollectionRecipientFields;
-    friend class TypeCollectionReshardingFields;
-    friend class VoteCommitIndexBuild;
-    friend class ImportCollectionOplogEntry;
-    friend class VoteCommitImportCollection;
-
-
 public:
     /**
      * The number of bytes contained in a UUID.
      */
-    static constexpr int kNumBytes = sizeof(UUIDStorage);
+    static constexpr int kNumBytes = 16;
 
     /**
      * Generate a new random v4 UUID per RFC 4122.
@@ -143,7 +80,7 @@ public:
     static UUID parse(const BSONObj& obj);
 
     static UUID fromCDR(ConstDataRange cdr) {
-        UUID uuid;
+        UUID uuid{UUIDStorage{}};
         invariant(cdr.length() == uuid._uuid.size());
         memcpy(uuid._uuid.data(), cdr.data(), uuid._uuid.size());
         return uuid;
@@ -242,19 +179,18 @@ public:
     }
 
 private:
-    UUID(const UUIDStorage& uuid) : _uuid(uuid) {}
+    using UUIDStorage = std::array<unsigned char, kNumBytes>;
 
-    /**
-     *  Should never be used, as the resulting UUID will not be unique.
-     *  The exception is in code generated by the IDL compiler, which itself ensures
-     *  such an invalid value cannot propagate.
-     */
-    friend class LogicalSessionId;
-    UUID() = default;
+    UUID(const UUIDStorage& uuid) : _uuid(uuid) {}
 
     UUIDStorage _uuid{};  // UUID in network byte order
 };
 
+/** Allow IDL-generated parsers to define uninitialized UUID objects. */
+inline auto idlPreparsedValue(stdx::type_identity<UUID>) {
+    return UUID::fromCDR(std::array<unsigned char, 16>{});
+}
+
 inline std::ostream& operator<<(std::ostream& s, const UUID& uuid) {
     return (s << uuid.toString());
 }