Avoiding IO completion callback during the closing

net/base/file_stream_win.cc

Index: net/base/file_stream_win.cc
===================================================================
--- net/base/file_stream_win.cc	(revision 16872)
+++ net/base/file_stream_win.cc	(working copy)
@@ -50,7 +50,7 @@
 class FileStream::AsyncContext : public MessageLoopForIO::IOHandler {
  public:
   AsyncContext(FileStream* owner)
-      : owner_(owner), context_(), callback_(NULL) {
+      : owner_(owner), context_(), callback_(NULL), is_closing_(false) {
     context_.handler = this;
   }
   ~AsyncContext();
@@ -67,9 +67,11 @@
   FileStream* owner_;
   MessageLoopForIO::IOContext context_;
   CompletionCallback* callback_;
+  bool is_closing_;
 };
 
 FileStream::AsyncContext::~AsyncContext() {
+  is_closing_ = true;
   bool waited = false;
   base::Time start = base::Time::Now();
   while (callback_) {
@@ -93,6 +95,11 @@
   DCHECK(&context_ == context);
   DCHECK(callback_);
 
+  if (is_closing_) {

[brettw, 2009/06/03 23:43:04]

Can you add a comment why this is here and what bad case we're trying to avoid?
Don't forget the Posix one too.

+    callback_ = NULL;
+    return;
+  }
+
   int result = static_cast<int>(bytes_read);
   if (error && error != ERROR_HANDLE_EOF)
     result = MapErrorCode(error);