CSHARP-1626: BsonBinaryWriter should support writing more than 2GB.

Author: rstam

src/MongoDB.Bson.Tests/IO/BsonBinaryWriterTests.cs

@@ -52,6 +52,29 @@ public void BsonBinaryWriter_should_support_writing_multiple_documents(
             }
         }
 
+        [Test]
+        public void BsonBinaryWriter_should_support_writing_more_than_2GB()
+        {
+            using (var stream = new NullBsonStream())
+            using (var binaryWriter = new BsonBinaryWriter(stream))
+            {
+                var bigBinaryData = new BsonBinaryData(new byte[int.MaxValue / 2 - 1000]);
+                for (var i = 0; i < 3; i++)
+                {
+                    binaryWriter.WriteStartDocument();
+                    binaryWriter.WriteName("x");
+                    binaryWriter.WriteBinaryData(bigBinaryData);
+                    binaryWriter.WriteEndDocument();
+                }
+
+                var smallBinaryData = new BsonBinaryData(new byte[2000]);
+                binaryWriter.WriteStartDocument();
+                binaryWriter.WriteName("x");
+                binaryWriter.WriteBinaryData(smallBinaryData);
+                binaryWriter.WriteEndDocument();
+            }
+        }
+
         [Test]
         [Requires64BitProcess]
         public void BackpatchSize_should_throw_when_size_is_larger_than_2GB()

src/MongoDB.Bson/IO/BsonBinaryWriter.cs

@@ -416,7 +416,7 @@ public override void WriteJavaScriptWithScope(string code)
 
             _bsonStream.WriteBsonType(BsonType.JavaScriptWithScope);
             WriteNameHelper();
-            _context = new BsonBinaryWriterContext(_context, ContextType.JavaScriptWithScope, (int)_bsonStream.Position);
+            _context = new BsonBinaryWriterContext(_context, ContextType.JavaScriptWithScope, _bsonStream.Position);
             _bsonStream.WriteInt32(0); // reserve space for size of JavaScript with scope value
             _bsonStream.WriteString(code, _settings.Encoding);
 
@@ -580,7 +580,7 @@ public override void WriteStartArray()
             base.WriteStartArray();
             _bsonStream.WriteBsonType(BsonType.Array);
             WriteNameHelper();
-            _context = new BsonBinaryWriterContext(_context, ContextType.Array, (int)_bsonStream.Position);
+            _context = new BsonBinaryWriterContext(_context, ContextType.Array, _bsonStream.Position);
             _bsonStream.WriteInt32(0); // reserve space for size
 
             State = BsonWriterState.Value;
@@ -604,7 +604,7 @@ public override void WriteStartDocument()
                 WriteNameHelper();
             }
             var contextType = (State == BsonWriterState.ScopeDocument) ? ContextType.ScopeDocument : ContextType.Document;
-            _context = new BsonBinaryWriterContext(_context, contextType, (int)_bsonStream.Position);
+            _context = new BsonBinaryWriterContext(_context, contextType, _bsonStream.Position);
             _bsonStream.WriteInt32(0); // reserve space for size
 
             State = BsonWriterState.Name;

src/MongoDB.Bson/IO/BsonBinaryWriterContext.cs

@@ -20,14 +20,14 @@ internal class BsonBinaryWriterContext
         // private fields
         private BsonBinaryWriterContext _parentContext;
         private ContextType _contextType;
-        private int _startPosition;
+        private long _startPosition;
         private int _index; // used when contextType is Array
 
         // constructors
         internal BsonBinaryWriterContext(
             BsonBinaryWriterContext parentContext,
             ContextType contextType,
-            int startPosition)
+            long startPosition)
         {
             _parentContext = parentContext;
             _contextType = contextType;
@@ -45,7 +45,7 @@ internal ContextType ContextType
             get { return _contextType; }
         }
 
-        internal int StartPosition
+        internal long StartPosition
         {
             get { return _startPosition; }
         }