Extend the IOBuffer to the disk cache....

net/base/io_buffer.h

Index: net/base/io_buffer.h
===================================================================
--- net/base/io_buffer.h	(revision 9532)
+++ net/base/io_buffer.h	(working copy)
@@ -19,7 +19,7 @@
     DCHECK(buffer_size);
     data_ = new char[buffer_size];
   }
-  explicit IOBuffer(char* buffer) : data_(buffer) {}
+  explicit IOBuffer(char* data) : data_(data) {}
   virtual ~IOBuffer() {
     delete[] data_;
   }
@@ -30,6 +30,20 @@
   char* data_;
 };
 
+// This class allows the creation of a temporary IOBuffer that doesn't really
+// own the underlying buffer. Please use this class only as a last resort.
+// A good example is the buffer for a synchronous operation, where we can be
+// sure that nobody is keeping an extra reference to this object so the lifetime
+// of the buffer can be completely managed by its intended owner.
+class WrappedIOBuffer : public net::IOBuffer {
+ public:
+  explicit WrappedIOBuffer(const char* data)
+      : net::IOBuffer(const_cast<char*>(data)) {}
+  ~WrappedIOBuffer() {
+    data_ = NULL;
+  }
+};
+
 }  // namespace net
 
 #endif  // NET_BASE_IO_BUFFER_H_