Support overlapping operations on the SimpleEntryImpl.

net/disk_cache/simple/simple_entry_impl.h

Index: net/disk_cache/simple/simple_entry_impl.h
diff --git a/net/disk_cache/simple/simple_entry_impl.h b/net/disk_cache/simple/simple_entry_impl.h
index 7b898cf4881f68f2c019ccd14c065c7261b18796..3a4040a8df56d273727cdbe2c3794491a063b56b 100644
--- a/net/disk_cache/simple/simple_entry_impl.h
+++ b/net/disk_cache/simple/simple_entry_impl.h
@@ -5,6 +5,7 @@
 #ifndef NET_DISK_CACHE_SIMPLE_SIMPLE_ENTRY_IMPL_H_
 #define NET_DISK_CACHE_SIMPLE_SIMPLE_ENTRY_IMPL_H_
 
+#include <queue>
 #include <string>
 
 #include "base/files/file_path.h"
@@ -45,6 +46,9 @@ class SimpleEntryImpl : public Entry {
                        const std::string& key,
                        const CompletionCallback& callback);
 
+  std::string key() const { return key_; }
+  void RunNextOperationIfNeeded();
+
   // From Entry:
   virtual void Doom() OVERRIDE;
   virtual void Close() OVERRIDE;
@@ -57,6 +61,7 @@ class SimpleEntryImpl : public Entry {
                        net::IOBuffer* buf,
                        int buf_len,
                        const CompletionCallback& callback) OVERRIDE;
+
   virtual int WriteData(int index,
                         int offset,
                         net::IOBuffer* buf,
@@ -85,6 +90,22 @@ class SimpleEntryImpl : public Entry {
 
   virtual ~SimpleEntryImpl();
 
+  void DoomInternal();
+
+  void ReadDataInternal(int index,
+                        int offset,
+                        scoped_refptr<net::IOBuffer> buf,
+                        int buf_len,
+                        const CompletionCallback& callback);
+  void WriteDataInternal(int index,
+                         int offset,
+                         scoped_refptr<net::IOBuffer> buf,
+                         int buf_len,
+                         const CompletionCallback& callback,
+                         bool truncate);
+
+
+
   // Called after a SimpleSynchronousEntry has completed CreateEntry() or
   // OpenEntry(). Constructs the new SimpleEntryImpl (if |result| is net::OK)
   // and passes it back to the caller via |out_entry|. Also runs
@@ -141,6 +162,10 @@ class SimpleEntryImpl : public Entry {
   // threads to access the |synchronous_entry_| simultaneously.
   bool synchronous_entry_in_use_by_worker_;
 
+  bool read_only_operation_;
+  std::queue<base::Closure> operations_;
+
+
   base::WeakPtr<SimpleIndex> index_;
 };