1 files changed, 56 insertions, 0 deletions
diff --git a/csharp/ProtocolBuffers/InvalidProtocolBufferException.cs b/csharp/ProtocolBuffers/InvalidProtocolBufferException.cs
index 8b61f9f1..bf898722 100644
--- a/csharp/ProtocolBuffers/InvalidProtocolBufferException.cs
+++ b/csharp/ProtocolBuffers/InvalidProtocolBufferException.cs
@@ -2,6 +2,62 @@
 using System.IO;
 
 namespace Google.ProtocolBuffers {
+  /// <summary>
+  /// Thrown when a protocol message being parsed is invalid in some way,
+  /// e.g. it contains a malformed varint or a negative byte length.
+  /// 
+  /// TODO(jonskeet): Make the methods throw directly? Rename them?
+  /// </summary>
   public class InvalidProtocolBufferException : IOException {
+
+    private InvalidProtocolBufferException(string message)
+      : base(message) {
+    }
+
+    internal static InvalidProtocolBufferException TruncatedMessage() {
+      return new InvalidProtocolBufferException(
+        "While parsing a protocol message, the input ended unexpectedly " +
+        "in the middle of a field.  This could mean either than the " +
+        "input has been truncated or that an embedded message " +
+        "misreported its own length.");
+    }
+
+    internal static InvalidProtocolBufferException NegativeSize() {
+      return new InvalidProtocolBufferException(
+        "CodedInputStream encountered an embedded string or message " +
+        "which claimed to have negative size.");
+    }
+
+    internal static InvalidProtocolBufferException MalformedVarint() {
+      return new InvalidProtocolBufferException(
+        "CodedInputStream encountered a malformed varint.");
+    }
+
+    internal static InvalidProtocolBufferException InvalidTag() {
+      return new InvalidProtocolBufferException(
+        "Protocol message contained an invalid tag (zero).");
+    }
+
+    internal static InvalidProtocolBufferException InvalidEndTag() {
+      return new InvalidProtocolBufferException(
+        "Protocol message end-group tag did not match expected tag.");
+    }
+
+    internal static InvalidProtocolBufferException InvalidWireType() {
+      return new InvalidProtocolBufferException(
+        "Protocol message tag had invalid wire type.");
+    }
+
+    internal static InvalidProtocolBufferException RecursionLimitExceeded() {
+      return new InvalidProtocolBufferException(
+        "Protocol message had too many levels of nesting.  May be malicious.  " +
+        "Use CodedInputStream.setRecursionLimit() to increase the depth limit.");
+    }
+
+    internal static InvalidProtocolBufferException SizeLimitExceeded() {
+      return new InvalidProtocolBufferException(
+        "Protocol message was too large.  May be malicious.  " +
+        "Use CodedInputStream.setSizeLimit() to increase the size limit.");
+    }
   }
 }